https://wiki.swarma.org/api.php?action=feedcontributions&user=Henry&feedformat=atom集智百科 - 复杂系统|人工智能|复杂科学|复杂网络|自组织 - 用户贡献 [zh-cn]2024-03-29T04:44:09Z用户贡献MediaWiki 1.35.0https://wiki.swarma.org/index.php?title=%E5%BE%AE%E5%88%86%E7%86%B5&diff=21965微分熵2021-02-24T05:41:56Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译。<br />
由CecileLi初步审校。<br />
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<br />
'''Differential entropy''' (also referred to as '''continuous entropy''') is a concept in [[information theory]] that began as an attempt by Shannon to extend the idea of (Shannon) [[information entropy|entropy]], a measure of average [[surprisal]] of a [[random variable]], to continuous [[probability distribution]]s. Unfortunately, Shannon did not derive this formula, and rather just assumed it was the correct continuous analogue of discrete entropy, but it is not.<ref>{{cite journal |author=Jaynes, E.T. |authorlink=Edwin Thompson Jaynes |title=Information Theory And Statistical Mechanics |journal=Brandeis University Summer Institute Lectures in Theoretical Physics |volume=3 |issue=sect. 4b |year=1963 |url=http://bayes.wustl.edu/etj/articles/brandeis.pdf |format=PDF}}</ref>{{rp|181–218}} The actual continuous version of discrete entropy is the [[limiting density of discrete points]] (LDDP). Differential entropy (described here) is commonly encountered in the literature, but it is a limiting case of the LDDP, and one that loses its fundamental association with discrete [[information entropy|entropy]].<br />
<br />
Differential entropy (also referred to as continuous entropy) is a concept in information theory that began as an attempt by Shannon to extend the idea of (Shannon) entropy, a measure of average surprisal of a random variable, to continuous probability distributions. Unfortunately, Shannon did not derive this formula, and rather just assumed it was the correct continuous analogue of discrete entropy, but it is not.<br />
<br />
<font color="#ff8000"> 微分熵Differential entropy</font>(也被称为连续熵)是信息论中的一个概念,其来源于香农尝试将他的香农熵的概念扩展到连续的概率分布。香农熵是衡量一个随机变量的平均惊异程度的指标。可惜的是,香农只是假设它是离散熵的正确连续模拟而并没有推导出公式,但事实上它并不是离散熵的正确连续模拟。<br />
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<math>h(X_1, \ldots, X_n) = \sum_{i=1}^{n} h(X_i|X_1, \ldots, X_{i-1}) \leq \sum_{i=1}^{n} h(X_i)</math>.<br />
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==Definition定义==<br />
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Let <math>X</math> be a random variable with a [[probability density function]] <math>f</math> whose [[support (mathematics)|support]] is a set <math>\mathcal X</math>. The ''differential entropy'' <math>h(X)</math> or <math>h(f)</math> is defined as<ref name="cover_thomas">{{cite book|first1=Thomas M.|first2=Joy A.|last1=Cover|last2=Thomas|isbn=0-471-06259-6|title=Elements of Information Theory|year=1991|publisher=Wiley|location=New York|url=https://archive.org/details/elementsofinform0000cove|url-access=registration}}</ref><br />
<math>h(X+c) = h(X)</math><br />
<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】此处缺无格式的英文及翻译 补充:设随机变量X,其概率密度函数F的的定义域是X的集合<br />
<br />
:<math>h(X) = -\int_\mathcal{X} f(x)\log f(x)\,dx</math><br />
<br />
For probability distributions which don't have an explicit density function expression, but have an explicit [[quantile function]] expression, <math>Q(p)</math>, then <math>h(Q)</math> can be defined in terms of the derivative of <math>Q(p)</math> i.e. the quantile density function <math>Q'(p)</math> as <ref>{{Citation |last1=Vasicek |first1=Oldrich |year=1976 |title=A Test for Normality Based on Sample Entropy |journal=[[Journal of the Royal Statistical Society, Series B]] |volume=38 |issue=1 |jstor=2984828 |postscript=. }}</ref>{{rp|54–59}}<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】此处缺无格式的英文及翻译 补充:For probability distributions which don't have an explicit density function expression, but have an explicit quantile function expression, , then can be defined in terms of the derivative of i.e. the quantile density function as<br />
对于没有显式密度函数表达式,但有显式分位数函数表达式的概率分布,我们则可以用分位数密度函数的导数来定义,即<br />
<br />
:<math>h(Q) = \int_0^1 \log Q'(p)\,dp</math>.<br />
<br />
A modification of differential entropy that addresses these drawbacks is the relative information entropy, also known as the Kullback–Leibler divergence, which includes an invariant measure factor (see limiting density of discrete points).<br />
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针对这些缺点,提出了一个改进的概念,即相对熵,也被称为 Kullback-Leibler 分歧,其中包括一个不变测度因子(见离散点的极限密度)。<br />
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As with its discrete analog, the units of differential entropy depend on the base of the [[logarithm]], which is usually 2 (i.e., the units are [[bit]]s). See [[logarithmic units]] for logarithms taken in different bases. Related concepts such as [[joint entropy|joint]], [[conditional entropy|conditional]] differential entropy, and [[Kullback–Leibler divergence|relative entropy]] are defined in a similar fashion. Unlike the discrete analog, the differential entropy has an offset that depends on the units used to measure <math>X</math>.<ref name="gibbs">{{cite book |last=Gibbs |first=Josiah Willard |authorlink=Josiah Willard Gibbs |title=[[Elementary Principles in Statistical Mechanics|Elementary Principles in Statistical Mechanics, developed with especial reference to the rational foundation of thermodynamics]] |year=1902 |publisher=Charles Scribner's Sons |location=New York}}</ref>{{rp|183–184}} For example, the differential entropy of a quantity measured in millimeters will be {{not a typo|log(1000)}} more than the same quantity measured in meters; a dimensionless quantity will have differential entropy of {{not a typo|log(1000)}} more than the same quantity divided by 1000.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:与离散模型一样,微分熵的单位取决于对数的底数,通常是2(单位:比特;请参阅对数单位,了解不同基数的对数。)相对熵的定义与联合熵、条件差分熵等概念相对熵的概念存在类似之处。与离散模型不同,差分熵的偏移量取决于测量单位。例如,以毫米为单位测量的量的差分熵将大于以米为单位测量的相同量;无量纲量的差分熵将大于相同量除以1000。<br />
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One must take care in trying to apply properties of discrete entropy to differential entropy, since probability density functions can be greater than 1. For example, the [[Uniform distribution (continuous)|uniform distribution]] <math>\mathcal{U}(0,1/2)</math> has ''negative'' differential entropy<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:在尝试将离散熵的性质应用于微分熵时必须小心,因为概率密度函数可以大于1。例如,均匀分布具有“负”微分熵<br />
<br />
:<math>\int_0^\frac{1}{2} -2\log(2)\,dx=-\log(2)\,</math>.<br />
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Thus, differential entropy does not share all properties of discrete entropy.<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:因此,微分熵并不具有离散熵的所有性质。<br />
<br />
Note that the continuous [[mutual information]] <math>I(X;Y)</math> has the distinction of retaining its fundamental significance as a measure of discrete information since it is actually the limit of the discrete mutual information of ''partitions'' of <math>X</math> and <math>Y</math> as these partitions become finer and finer. Thus it is invariant under non-linear [[homeomorphisms]] (continuous and uniquely invertible maps), <ref>{{cite journal | first = Alexander | last = Kraskov |author2=Stögbauer, Grassberger | year = 2004 | title = Estimating mutual information | journal = [[Physical Review E]] | volume = 60 | pages = 066138 | doi =10.1103/PhysRevE.69.066138|arxiv = cond-mat/0305641 |bibcode = 2004PhRvE..69f6138K }}</ref> including linear <ref name = Reza>{{ cite book | title = An Introduction to Information Theory | author = Fazlollah M. Reza | publisher = Dover Publications, Inc., New York | origyear = 1961| year = 1994 | isbn = 0-486-68210-2 | url = https://books.google.com/books?id=RtzpRAiX6OgC&pg=PA8&dq=intitle:%22An+Introduction+to+Information+Theory%22++%22entropy+of+a+simple+source%22&as_brr=0&ei=zP79Ro7UBovqoQK4g_nCCw&sig=j3lPgyYrC3-bvn1Td42TZgTzj0Q }}</ref> transformations of <math>X</math> and <math>Y</math>, and still represents the amount of discrete information that can be transmitted over a channel that admits a continuous space of values.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:注意,连续相互变量I(X;Y)具有保留其作为离散信息度量的基本意义的区别,因为它实际上是X和Y的“分区”的离散互信息的极限,因为这些分区变得越来越细。因此,它在非线性[[同胚]](连续且唯一可逆的映射)下是不变的,并且仍然表示可在允许连续值空间的信道上传输的离散信息量。<br />
<br />
For the direct analogue of discrete entropy extended to the continuous space, see [[limiting density of discrete points]].<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:对于扩展到连续空间的离散熵的直接模拟,参见[[离散点的极限密度]]。<br />
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==Properties of differential entropy==<br />
微分熵的性质<br />
* For probability densities <math>f</math> and <math>g</math>, the [[Kullback–Leibler divergence]] <math>D_{KL}(f || g)</math> is greater than or equal to 0 with equality only if <math>f=g</math> [[almost everywhere]]. Similarly, for two random variables <math>X</math> and <math>Y</math>, <math>I(X;Y) \ge 0</math> and <math>h(X|Y) \le h(X)</math> with equality [[if and only if]] <math>X</math> and <math>Y</math> are [[Statistical independence|independent]].<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:*对于概率密度f和g,[[Kullback–Leibler散度]]D{KL}(f | | g)</math>只有在f=g[[几乎处处]]时才大于或等于0且相等。类似地,对于两个随机变量X和Y,I(X;Y)\ge 和h(X | Y)\le h(X),等式:当且仅当>X和Y是[[统计独立性|独立性]]。<br />
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* The chain rule for differential entropy holds as in the discrete case<ref name="cover_thomas" />{{rp|253}}<br />
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--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:微分熵的链式法则在离散情况下成立<br />
<br />
::<math>h(X_1, \ldots, X_n) = \sum_{i=1}^{n} h(X_i|X_1, \ldots, X_{i-1}) \leq \sum_{i=1}^{n} h(X_i)</math>.<br />
<br />
* Differential entropy is translation invariant, i.e. for a constant <math>c</math>.<ref name="cover_thomas" />{{rp|253}}<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:微分熵是平移不变的,即对于常数c存在<br />
<br />
::<math>h(X+c) = h(X)</math><br />
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* Differential entropy is in general not invariant under arbitrary invertible maps.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:在任意可逆映射下,微分熵一般是不不变的。<br />
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:: In particular, for a constant <math>a</math><br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:特别地,对于一个常数a存在<br />
<br />
:::<math>h(aX) = h(X)+ \log |a|</math><br />
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:: For a vector valued random variable <math>\mathbf{X}</math> and an invertible (square) [[matrix (mathematics)|matrix]] <math>\mathbf{A}</math><br />
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--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:对于向量值随机变量X和可逆(平方)矩阵存在<br />
<br />
:::<math>h(\mathbf{A}\mathbf{X})=h(\mathbf{X})+\log \left( |\det \mathbf{A}| \right)</math><ref name="cover_thomas" />{{rp|253}}<br />
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* In general, for a transformation from a random vector to another random vector with same dimension <math>\mathbf{Y}=m \left(\mathbf{X}\right)</math>, the corresponding entropies are related via<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:一般地,对于从一个随机向量到另一个具有相同维数(X,Y)的随机向量的变换,相应的熵通过<br />
<br />
::<math>h(\mathbf{Y}) \leq h(\mathbf{X}) + \int f(x) \log \left\vert \frac{\partial m}{\partial x} \right\vert dx</math><br />
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:where <math>\left\vert \frac{\partial m}{\partial x} \right\vert</math> is the [[Jacobian matrix and determinant|Jacobian]] of the transformation <math>m</math>.<ref>{{cite web |title=proof of upper bound on differential entropy of f(X) |work=[[Stack Exchange]] |date=April 16, 2016 |url=https://math.stackexchange.com/q/1745670 }}</ref> The above inequality becomes an equality if the transform is a bijection. Furthermore, when <math>m</math> is a rigid rotation, translation, or combination thereof, the Jacobian determinant is always 1, and <math>h(Y)=h(X)</math>.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:其中(m,x)是变换m的[[Jacobian矩阵和行列式| Jacobian]]。如果变换是双射,则上述不等式变为等式。此外,当m是刚性旋转、平移或其组合时,雅可比行列式总是1,并且h(Y)=h(X)<br />
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* If a random vector <math>X \in \mathbb{R}^n</math> has mean zero and [[covariance]] matrix <math>K</math>, <math>h(\mathbf{X}) \leq \frac{1}{2} \log(\det{2 \pi e K}) = \frac{1}{2} \log[(2\pi e)^n \det{K}]</math> with equality if and only if <math>X</math> is [[Multivariate normal distribution#Joint normality|jointly gaussian]] (see [[#Maximization in the normal distribution|below]]).<ref name="cover_thomas" />{{rp|254}}<br />
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--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:如果一个随机向量X具有均值零和协方差矩阵<math>K</math>,<math>h(\mathbf{X})\leq\frac{1}{2}\log(\det{2\pi e K})=\frac{1}{2}\log[(2\pi e)^n\det{K}]</math>等式当且仅当X为多元正态分布/联合正态性/联合高斯(见下文[[#正态分布中的最大化])。<br />
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* It is not invariant under [[change of variables]], and is therefore most useful with dimensionless variables.<br />
它在变量变化下不是不变的,因此对无量纲变量最有用 <br />
* It can be negative.<br />
它可以为负<br />
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A modification of differential entropy that addresses these drawbacks is the '''relative information entropy''', also known as the Kullback–Leibler divergence, which includes an [[invariant measure]] factor (see [[limiting density of discrete points]]).<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:<br />
解决这些缺点的微分熵的一种改进是“相对信息熵”,也称为Kullback–Leibler散度,它包括一个“不变测度”因子(参见:离散点的极限密度)。<br />
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==Maximization in the normal distribution==<br />
正态分布中的最大化<br />
===Theorem===<br />
理论<br />
Its differential entropy is then<br />
它的微分熵就会<br />
With a [[normal distribution]], differential entropy is maximized for a given variance. A Gaussian random variable has the largest entropy amongst all random variables of equal variance, or, alternatively, the maximum entropy distribution under constraints of mean and variance is the Gaussian.<ref name="cover_thomas" /><br />
对于正态分布,对于给定的方差,微分熵是最大的。在所有等方差随机变量中,高斯随机变量的熵最大,或者在均值和方差约束下的最大熵分布是高斯分布<br />
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===Proof===<br />
证明<br />
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Let <math>g(x)</math> be a [[Normal distribution|Gaussian]] [[Probability density function|PDF]] with mean μ and variance <math>\sigma^2</math> and <math>f(x)</math> an arbitrary [[Probability density function|PDF]] with the same variance. Since differential entropy is translation invariant we can assume that <math>f(x)</math> has the same mean of <math>\mu</math> as <math>g(x)</math>.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:设<math>g(x)</math>是一个[[正态分布|高斯]][[概率密度函数| PDF]],具有均值μ和方差<math>\sigma^2</math>和<math>f(x)</math>具有相同方差的任意[[概率密度函数| PDF]]。由于微分熵是平移不变性的,我们可以假设<math>f(x)</math>与<math>g(x)</math>具有相同的<math>\mu</math>平均值。<br />
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Consider the [[Kullback–Leibler divergence]] between the two distributions<br />
:<math> 0 \leq D_{KL}(f || g) = \int_{-\infty}^\infty f(x) \log \left( \frac{f(x)}{g(x)} \right) dx = -h(f) - \int_{-\infty}^\infty f(x)\log(g(x)) dx.</math><br />
Now note that<br />
:<math>\begin{align}<br />
\int_{-\infty}^\infty f(x)\log(g(x)) dx &= \int_{-\infty}^\infty f(x)\log\left( \frac{1}{\sqrt{2\pi\sigma^2}}e^{-\frac{(x-\mu)^2}{2\sigma^2}}\right) dx \\<br />
&= \int_{-\infty}^\infty f(x) \log\frac{1}{\sqrt{2\pi\sigma^2}} dx + \log(e)\int_{-\infty}^\infty f(x)\left( -\frac{(x-\mu)^2}{2\sigma^2}\right) dx \\<br />
&= -\tfrac{1}{2}\log(2\pi\sigma^2) - \log(e)\frac{\sigma^2}{2\sigma^2} \\<br />
&= -\tfrac{1}{2}\left(\log(2\pi\sigma^2) + \log(e)\right) \\<br />
&= -\tfrac{1}{2}\log(2\pi e \sigma^2) \\<br />
&= -h(g)<br />
\end{align}</math><br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:考虑两个分布之间的[[Kullback–Leibler散度]]<br />
<br />
:<math>0\leq D{KL}(f{g)=\int{-\infty}^\infty f(x)\log\left(\frac{f(x)}{g(x)}\right)dx=-h(f)-\int{-\infty}^\infty f(x)\log(g(x))dx。</math><br />
<br />
现在请注意<br />
:<math>\begin{align}<br />
\int_{-\infty}^\infty f(x)\log(g(x)) dx &= \int_{-\infty}^\infty f(x)\log\left( \frac{1}{\sqrt{2\pi\sigma^2}}e^{-\frac{(x-\mu)^2}{2\sigma^2}}\right) dx \\<br />
&= \int_{-\infty}^\infty f(x) \log\frac{1}{\sqrt{2\pi\sigma^2}} dx + \log(e)\int_{-\infty}^\infty f(x)\left( -\frac{(x-\mu)^2}{2\sigma^2}\right) dx \\<br />
&= -\tfrac{1}{2}\log(2\pi\sigma^2) - \log(e)\frac{\sigma^2}{2\sigma^2} \\<br />
&= -\tfrac{1}{2}\left(\log(2\pi\sigma^2) + \log(e)\right) \\<br />
&= -\tfrac{1}{2}\log(2\pi e \sigma^2) \\<br />
&= -h(g)<br />
\end{align}</math><br />
<br />
because the result does not depend on <math>f(x)</math> other than through the variance. Combining the two results yields<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:因为结果不依赖于<math>f(x)</math>而不是通过方差。将这两个结果结合起来就得到了<br />
<br />
:<math> h(g) - h(f) \geq 0 \!</math><br />
<br />
with equality when <math>f(x)=g(x)</math> following from the properties of Kullback–Leibler divergence.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:当f(x)=g(x)</math>遵循Kullback-Leibler散度的性质时相等。<br />
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===Alternative proof===<br />
替代证明<br />
<br />
This result may also be demonstrated using the [[variational calculus]]. A Lagrangian function with two [[Lagrangian multiplier]]s may be defined as:<br />
<br />
:<math>L=\int_{-\infty}^\infty g(x)\ln(g(x))\,dx-\lambda_0\left(1-\int_{-\infty}^\infty g(x)\,dx\right)-\lambda\left(\sigma^2-\int_{-\infty}^\infty g(x)(x-\mu)^2\,dx\right)</math><br />
<br />
where ''g(x)'' is some function with mean μ. When the entropy of ''g(x)'' is at a maximum and the constraint equations, which consist of the normalization condition <math>\left(1=\int_{-\infty}^\infty g(x)\,dx\right)</math> and the requirement of fixed variance <math>\left(\sigma^2=\int_{-\infty}^\infty g(x)(x-\mu)^2\,dx\right)</math>, are both satisfied, then a small variation δ''g''(''x'') about ''g(x)'' will produce a variation δ''L'' about ''L'' which is equal to zero:<br />
<br />
:<math>0=\delta L=\int_{-\infty}^\infty \delta g(x)\left (\ln(g(x))+1+\lambda_0+\lambda(x-\mu)^2\right )\,dx</math><br />
<br />
Since this must hold for any small δ''g''(''x''), the term in brackets must be zero, and solving for ''g(x)'' yields:<br />
<br />
:<math>g(x)=e^{-\lambda_0-1-\lambda(x-\mu)^2}</math><br />
<br />
Using the constraint equations to solve for λ<sub>0</sub> and λ yields the normal distribution:<br />
<br />
:<math>g(x)=\frac{1}{\sqrt{2\pi\sigma^2}}e^{-\frac{(x-\mu)^2}{2\sigma^2}}</math><br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:<br />
这个结果也可以用[[变分演算]]来证明。具有两个[[拉格朗日乘子]]的拉格朗日函数可定义为:<br />
<br />
<br />
<br />
:<math>L=\int{-\infty}^\infty g(x)\ln(g(x))\,dx-\lambda\u 0\左(1-\int{-\infty}^\infty g(x)\,dx\右)-\lambda\左(\sigma^2-\int{-\infty}^\infty g(x)(x-\mu)^2\,dx\右)</math><br />
<br />
<br />
<br />
其中“g(x)”是平均μ的函数。当“g(x)”的熵为最大值时,由归一化条件<math>\ left(1=\int{-\infty}^\infty g(x)\,dx\ right)</math>和固定方差<math>\ left(\sigma^2=\int{-\infty}^\infty g(x)(x-\mu)^2\,dx\ right)</math>组成的约束方程均满足,然后,关于“g(x)”的微小变化δ“g”(“x”)将产生关于“L”的变化δ“L”,其等于零:<br />
<br />
<br />
<br />
:<math>0=\delta L=\int{-\infty}^\infty\delta g(x)\left(\ln(g(x))+1+\lambda\u 0+\lambda(x-\mu)^2\ right)\,dx</math><br />
<br />
<br />
<br />
由于这必须适用于任何小δ“g”(“x”),括号中的项必须为零,求解“g(x)”得到:<br />
<br />
<br />
<br />
:<math>g(x)=e^{-\lambda\u 0-1-\lambda(x-\mu)^2}</math><br />
<br />
<br />
<br />
使用约束方程求解λ<sub>0</sub>和λ得出正态分布:<br />
<br />
<br />
<br />
:<math>g(x)=\frac{1}{\sqrt{2\pi\sigma^2}}e^{-\frac{(x-\mu)^2}{2\sigma^2}}</math><br />
<br />
==Example: Exponential distribution==<br />
例子:指数分布<br />
Let <math>X</math> be an [[exponential distribution|exponentially distributed]] random variable with parameter <math>\lambda</math>, that is, with probability density function<br />
<br />
:<math>f(x) = \lambda e^{-\lambda x} \mbox{ for } x \geq 0.</math><br />
<br />
Its differential entropy is then<br />
{|<br />
|-<br />
| <math>h_e(X)\,</math><br />
| <math>=-\int_0^\infty \lambda e^{-\lambda x} \log (\lambda e^{-\lambda x})\,dx</math><br />
|-<br />
|<br />
| <math>= -\left(\int_0^\infty (\log \lambda)\lambda e^{-\lambda x}\,dx + \int_0^\infty (-\lambda x) \lambda e^{-\lambda x}\,dx\right) </math><br />
|-<br />
|<br />
| <math>= -\log \lambda \int_0^\infty f(x)\,dx + \lambda E[X]</math><br />
|-<br />
|<br />
| <math>= -\log\lambda + 1\,.</math><br />
|}<br />
<br />
Here, <math>h_e(X)</math> was used rather than <math>h(X)</math> to make it explicit that the logarithm was taken to base ''e'', to simplify the calculation.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:<br />
设<math>X</math>为[[指数分布|指数分布]]随机变量,参数为<math>\lambda</math>,即概率密度函数<br />
<br />
<br />
<br />
:<math>f(x)=\lambda e^{-\lambda x}\mbox{for}x\geq 0.</math><br />
<br />
<br />
<br />
它的微分熵是<br />
<br />
{|<br />
<br />
|-<br />
<br />
|<math>h\u e(X)\,</math><br />
<br />
|<math>=-\int\u 0^\infty\lambda e^{-\lambda x}\log(\lambda e^{-\lambda x})\,dx</math><br />
<br />
|-<br />
<br />
|<br />
<br />
|<math>=-\left(\int\u 0^\infty(\log\lambda)\lambda e^{-\lambda x}\,dx+\int\u 0^\infty(-\lambda x)\lambda e^{-\lambda x}\,dx\right)</math><br />
<br />
|-<br />
<br />
|<br />
<br />
|<math>=-\log\lambda\int\u 0^\infty f(x)\,dx+\lambda E[x]</math><br />
<br />
|-<br />
<br />
|<br />
<br />
|<math>=-\log\lambda+1\,.</math><br />
<br />
|}<br />
<br />
<br />
<br />
这里,使用<math>h(X)</math>而不是<math>h(X)</math>来明确对数取基数“e”,以简化计算。<br />
<br />
==Relation to estimator error==<br />
The differential entropy yields a lower bound on the expected squared error of an [[estimator]]. For any random variable <math>X</math> and estimator <math>\widehat{X}</math> the following holds:<ref name="cover_thomas" /><br />
:<math>\operatorname{E}[(X - \widehat{X})^2] \ge \frac{1}{2\pi e}e^{2h(X)}</math><br />
with equality if and only if <math>X</math> is a Gaussian random variable and <math>\widehat{X}</math> is the mean of <math>X</math>.<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:<br />
<br />
==与估计器误差的关系==<br />
<br />
微分熵给出了[[估计量]]的期望平方误差的下界。对于任何随机变量<math>X</math>和估计器<math>\widehat{X}</math>来说,以下条件成立:<ref name=“cover\u thomas”/><br />
<br />
:<math>\operatorname{E}[(X-\widehat{X})^2]\ge\frac{1}{2\pi E}E^{2h(X)}</math><br />
<br />
当且仅当<math>X</math>是高斯随机变量,<math>\widehat{X}</math>是<math>X</math>的平均值。<br />
<br />
==Differential entropies for various distributions==<br />
<br />
In the table below <math>\Gamma(x) = \int_0^{\infty} e^{-t} t^{x-1} dt</math> is the [[gamma function]], <math>\psi(x) = \frac{d}{dx} \ln\Gamma(x)=\frac{\Gamma'(x)}{\Gamma(x)}</math> is the [[digamma function]], <math>B(p,q) = \frac{\Gamma(p)\Gamma(q)}{\Gamma(p+q)}</math> is the [[beta function]], and γ<sub>''E''</sub> is [[Euler-Mascheroni constant|Euler's constant]].<ref>{{cite journal |last1=Park |first1=Sung Y. |last2=Bera |first2=Anil K. |year=2009 |title=Maximum entropy autoregressive conditional heteroskedasticity model |journal=Journal of Econometrics |publisher=Elsevier |url=http://www.wise.xmu.edu.cn/Master/Download/..%5C..%5CUploadFiles%5Cpaper-masterdownload%5C2009519932327055475115776.pdf |access-date=2011-06-02 |archive-url=https://web.archive.org/web/20160307144515/http://wise.xmu.edu.cn/uploadfiles/paper-masterdownload/2009519932327055475115776.pdf |archive-date=2016-03-07 |url-status=dead }}</ref>{{rp|219–230}}<br />
{| class="wikitable" style="background:white"<br />
|+ Table of differential entropies<br />
|-<br />
! Distribution Name !! Probability density function (pdf) !! Entropy in [[Nat (unit)|nat]]s || Support<br />
|-<br />
| [[Uniform distribution (continuous)|Uniform]] || <math>f(x) = \frac{1}{b-a}</math> || <math>\ln(b - a) \,</math> ||<math>[a,b]\,</math><br />
|-<br />
| [[Normal distribution|Normal]] || <math>f(x) = \frac{1}{\sqrt{2\pi\sigma^2}} \exp\left(-\frac{(x-\mu)^2}{2\sigma^2}\right)</math> || <math>\ln\left(\sigma\sqrt{2\,\pi\,e}\right) </math>||<math>(-\infty,\infty)\,</math><br />
|-<br />
| [[Exponential distribution|Exponential]] || <math>f(x) = \lambda \exp\left(-\lambda x\right)</math> || <math>1 - \ln \lambda \, </math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Rayleigh distribution|Rayleigh]] || <math>f(x) = \frac{x}{\sigma^2} \exp\left(-\frac{x^2}{2\sigma^2}\right)</math> || <math>1 + \ln \frac{\sigma}{\sqrt{2}} + \frac{\gamma_E}{2}</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Beta distribution|Beta]] || <math>f(x) = \frac{x^{\alpha-1}(1-x)^{\beta-1}}{B(\alpha,\beta)}</math> for <math>0 \leq x \leq 1</math> || <math> \ln B(\alpha,\beta) - (\alpha-1)[\psi(\alpha) - \psi(\alpha +\beta)]\,</math><br /><math>- (\beta-1)[\psi(\beta) - \psi(\alpha + \beta)] \, </math>||<math>[0,1]\,</math><br />
|-<br />
| [[Cauchy distribution|Cauchy]] || <math>f(x) = \frac{\gamma}{\pi} \frac{1}{\gamma^2 + x^2}</math> || <math>\ln(4\pi\gamma) \, </math>||<math>(-\infty,\infty)\,</math><br />
|-<br />
| [[Chi distribution|Chi]] || <math>f(x) = \frac{2}{2^{k/2} \Gamma(k/2)} x^{k-1} \exp\left(-\frac{x^2}{2}\right)</math> || <math>\ln{\frac{\Gamma(k/2)}{\sqrt{2}}} - \frac{k-1}{2} \psi\left(\frac{k}{2}\right) + \frac{k}{2}</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Chi-squared distribution|Chi-squared]] || <math>f(x) = \frac{1}{2^{k/2} \Gamma(k/2)} x^{\frac{k}{2}\!-\!1} \exp\left(-\frac{x}{2}\right)</math> || <math>\ln 2\Gamma\left(\frac{k}{2}\right) - \left(1 - \frac{k}{2}\right)\psi\left(\frac{k}{2}\right) + \frac{k}{2}</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Erlang distribution|Erlang]] || <math>f(x) = \frac{\lambda^k}{(k-1)!} x^{k-1} \exp(-\lambda x)</math> || <math>(1-k)\psi(k) + \ln \frac{\Gamma(k)}{\lambda} + k</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[F distribution|F]] || <math>f(x) = \frac{n_1^{\frac{n_1}{2}} n_2^{\frac{n_2}{2}}}{B(\frac{n_1}{2},\frac{n_2}{2})} \frac{x^{\frac{n_1}{2} - 1}}{(n_2 + n_1 x)^{\frac{n_1 + n2}{2}}}</math> || <math>\ln \frac{n_1}{n_2} B\left(\frac{n_1}{2},\frac{n_2}{2}\right) + \left(1 - \frac{n_1}{2}\right) \psi\left(\frac{n_1}{2}\right) -</math><br /><math>\left(1 + \frac{n_2}{2}\right)\psi\left(\frac{n_2}{2}\right) + \frac{n_1 + n_2}{2} \psi\left(\frac{n_1\!+\!n_2}{2}\right)</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Gamma distribution|Gamma]] || <math>f(x) = \frac{x^{k - 1} \exp(-\frac{x}{\theta})}{\theta^k \Gamma(k)}</math> || <math>\ln(\theta \Gamma(k)) + (1 - k)\psi(k) + k \, </math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Laplace distribution|Laplace]] || <math>f(x) = \frac{1}{2b} \exp\left(-\frac{|x - \mu|}{b}\right)</math> || <math>1 + \ln(2b) \, </math>||<math>(-\infty,\infty)\,</math><br />
|-<br />
| [[Logistic distribution|Logistic]] || <math>f(x) = \frac{e^{-x}}{(1 + e^{-x})^2}</math> || <math>2 \, </math>||<math>(-\infty,\infty)\,</math><br />
|-<br />
| [[Log-normal distribution|Lognormal]] || <math>f(x) = \frac{1}{\sigma x \sqrt{2\pi}} \exp\left(-\frac{(\ln x - \mu)^2}{2\sigma^2}\right)</math> || <math>\mu + \frac{1}{2} \ln(2\pi e \sigma^2)</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Maxwell–Boltzmann distribution|Maxwell–Boltzmann]] || <math>f(x) = \frac{1}{a^3}\sqrt{\frac{2}{\pi}}\,x^{2}\exp\left(-\frac{x^2}{2a^2}\right)</math> || <math>\ln(a\sqrt{2\pi})+\gamma_E-\frac{1}{2}</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Generalized Gaussian distribution|Generalized normal]] || <math>f(x) = \frac{2 \beta^{\frac{\alpha}{2}}}{\Gamma(\frac{\alpha}{2})} x^{\alpha - 1} \exp(-\beta x^2)</math> || <math>\ln{\frac{\Gamma(\alpha/2)}{2\beta^{\frac{1}{2}}}} - \frac{\alpha - 1}{2} \psi\left(\frac{\alpha}{2}\right) + \frac{\alpha}{2}</math>||<math>(-\infty,\infty)\,</math><br />
|-<br />
| [[Pareto distribution|Pareto]] || <math>f(x) = \frac{\alpha x_m^\alpha}{x^{\alpha+1}}</math> || <math>\ln \frac{x_m}{\alpha} + 1 + \frac{1}{\alpha}</math>||<math>[x_m,\infty)\,</math><br />
|-<br />
| [[Student's t-distribution|Student's t]] || <math>f(x) = \frac{(1 + x^2/\nu)^{-\frac{\nu+1}{2}}}{\sqrt{\nu}B(\frac{1}{2},\frac{\nu}{2})}</math> || <math>\frac{\nu\!+\!1}{2}\left(\psi\left(\frac{\nu\!+\!1}{2}\right)\!-\!\psi\left(\frac{\nu}{2}\right)\right)\!+\!\ln \sqrt{\nu} B\left(\frac{1}{2},\frac{\nu}{2}\right)</math>||<math>(-\infty,\infty)\,</math><br />
|-<br />
| [[Triangular distribution|Triangular]] || <math> f(x) = \begin{cases}<br />
\frac{2(x-a)}{(b-a)(c-a)} & \mathrm{for\ } a \le x \leq c, \\[4pt]<br />
\frac{2(b-x)}{(b-a)(b-c)} & \mathrm{for\ } c < x \le b, \\[4pt]<br />
\end{cases}</math> || <math>\frac{1}{2} + \ln \frac{b-a}{2}</math>||<math>[0,1]\,</math><br />
|-<br />
| [[Weibull distribution|Weibull]] || <math>f(x) = \frac{k}{\lambda^k} x^{k-1} \exp\left(-\frac{x^k}{\lambda^k}\right)</math> || <math>\frac{(k-1)\gamma_E}{k} + \ln \frac{\lambda}{k} + 1</math>||<math>[0,\infty)\,</math><br />
|-<br />
| [[Multivariate normal distribution|Multivariate normal]] || <math><br />
f_X(\vec{x}) =</math><br /><math> \frac{\exp \left( -\frac{1}{2} ( \vec{x} - \vec{\mu})^\top \Sigma^{-1}\cdot(\vec{x} - \vec{\mu}) \right)} {(2\pi)^{N/2} \left|\Sigma\right|^{1/2}}</math> || <math>\frac{1}{2}\ln\{(2\pi e)^{N} \det(\Sigma)\}</math>||<math>\mathbb{R}^N</math><br />
|-<br />
|}<br />
<br />
Many of the differential entropies are from.<ref name="lazorathie">{{cite journal|author=Lazo, A. and P. Rathie|title=On the entropy of continuous probability distributions|journal=IEEE Transactions on Information Theory|year=1978|volume=24 |issue=1|doi=10.1109/TIT.1978.1055832|pages=120–122}}</ref>{{rp|120–122}}<br />
<br />
--[[用户:CecileLi|CecileLi]]([[用户讨论:CecileLi|讨论]]) 【审校】补充翻译:<br />
==各种分布的微分熵==<br />
<br />
<br />
<br />
在下表中,dt</math>是[[Gamma function]],<math>\psi(x)=\frac{d}{dx}\ln\Gamma(x)=\frac{\Gamma'(x)}{\Gamma(x)}</math>是[[digamma function]],<math>B(p,q)=\frac{\Gamma(p+q)}\Gamma(p+q){/math>是[[beta function]],γ<sub>''E'</sub>是[[Euler-Mascheroni常数| Euler常数]]。<ref>{引用期刊| last1=Park | first1=Sung Y.| last2=Bera | first2=Anil K.| year=2009 | title=Maximum熵自回归条件异方差模型|期刊=journal of Econometrics | publisher=Elsevier|网址=http://www.wise.xmu.edu.cn/Master/Download/..%5C..%5上传文件%5Cpaper masterdownload%5C2009519932327055475115776.pdf|访问日期=2011-06-02 |存档url=https://web.archive.org/web/20160307144515/http://智慧.xmu.edu.cn/uploadfiles/paper masterdownload/2009519932327055475115776.pdf |存档日期=2016-03-07 | url状态=dead}}</ref>{rp | 219–230}<br />
<br />
{| class=“wikitable”style=“b背景:白色"<br />
<br />
|+微分熵表<br />
<br />
|-<br />
<br />
! 分发名称!!概率密度函数(pdf)!![[Nat(unit)| Nat]]s | |支持中的熵<br />
|-<br />
<br />
|[[均匀分布(连续)|均匀]]| |<math>f(x)=\frac{1}{b-a}</math>| |<math>\ln(b-a)\,</math>|<math>[a,b]\,</math><br />
<br />
|-<br />
<br />
|[[正态分布|正态]]| |<math>f(x)=\frac{1}{\sqrt{2\pi\sigma^2}}\exp\left(\frac{(x-\mu)^2}{2\sigma^2}\right)</math>|<math>\ln left(\sigma\sqrt{2\,\pi\,e}\right)</math>|<math>(\infty,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[指数分布|指数]]| |<math>f(x)=\lambda\exp\left(-\lambda x\right)</math>| |<math>1-\ln\lambda\,</math>| |<math>[0,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[Rayleigh distribution | Rayleigh]]| |<math>f(x)=\frac{x}{\sigma^2}\exp\left(-\frac{x^2}{2\sigma^2}\right)</math>|<math>1+\ln\frac{\sigma}{\sqrt{2}+\frac{\gamma E}{2}</math>|{math>[0,\infty)\,</math><br />
<br />
|-<br />
<br />
|数学>f(x)f(x))=\frac{{x数学><br />
<br />
|-<br />
<br />
|[[Cauchy分布| Cauchy]]| |<math>f(x)=\frac{\gamma}{\pi}\frac{1}{\gamma^2+x^2}</math>|<math>\ln(4\pi\gamma)\,</math>|<math>(-infty,\infty)\,</math><br />
<br />
|-<br />
<br />
|[中国分布| Chi分布.[中国分布| Chi分布.[中国分布.[中国分布| Chi分布.]].[中国分布|中国分布| | |数学>f(x)x(x)的数学)=\分形{{2{{k/2{k/2}{k/2}γ(k/2)γ(k/2)}}x ^ k-1}x ^ x{2}</math>|</math>[0,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[卡方分布|卡方]]| |<math>f(x)=\frac{1}{2^{k/2}\Gamma(k/2)}x^{\frac{k}{2}\!-\!1} \exp\left(-\frac{x}{2}\right)</math>{k}{2}\ln 2\Gamma\left(\frac{k}{2}\right)-\left(1-\frac{k}{2}\right)</psi\left(\frac{k}{2}\right)+\frac{k}{2}</math>{k}\infty)\,</math><br />
<br />
|-<br />
<br />
|[[Erlang分布| Erlang]]| |<math>f(x)=\frac{\lambda^k}{(k-1)!}x^{k-1}\exp(-\lambda x)</math>| |<math>(1-k)\psi(k)+\ln\frac{\Gamma(k)}{\lambda}+k</math>| |<math>[0,\infty)\,</math><br />
<br />
|-<br />
<br />
|(F)分销部门的分销ӝF]ӝ数学|数学|数学|数学(x)方面的统计{分销部门的分销ӝ分销保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保保n{u 1+n2}{2}}</math>{math>\ln\frac{n{u 1}{n}u 2}B\左(\frac{n{u 1}{2}),\frac{n{u 2}{2}\right)+\left(1-\frac{n{u 1}{2}\right)\psi\ left(\frac{n{u 1}{2}\right)</math><br/><math>\ left(1+\frac{n{u 2}{2}\right)\psi\ left(\frac{n{u 2}\right)+\frac{n{u 1+n{u 2}\psi\ left(\frac{n{u 1}\right)!+\!n\u 2}{2}\右)</math>| |<math>[0,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[Gamma distribution | Gamma]]| |<math>f(x)=\frac{x^{k-1}\exp(-\frac{x}{\theta})}{\theta^k\Gamma(k)}</math>|<math>\ln(\theta\Gamma(k))+(1-k)\psi(k)+k\,</math>|<math>[0,\infty)\,</math><br />
<br />
|-<br />
<br />
|拉普拉斯分布<br />
<br />
|-<br />
<br />
|[[Logistic distribution | Logistic]]| |<math>f(x)=\frac{e^{-x}{(1+e^{-x})^2}</math>|<math>2\,</math>|<math>(\infty,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[Log normal distribution | Lognormal]]| |<math>f(x)=\frac{1}{\sigma x\sqrt{2\pi}}\exp\left(\frac{(\ln x-\mu)^2}{2\sigma^2}\right)</math>| |<math>\mu+\frac{1}{2}\ln 2\pie\sigma^2)</math>|{math>[0,infty)\,</math><br />
|-<br />
<br />
|[[Maxwell-Boltzmann分布| Maxwell-Boltzmann]]| |<math>f(x)=\frac{1}{a^3}\sqrt{\frac{2}{\pi}}\,x^{2}\exp\左(\frac{x^2}{2a^2}\右)</math>| |<math>\ln(a\sqrt{2\pi})+\gamma u E-\frac{1}2}</math |<math>[0,infty)\,</math>><br />
<br />
|-<br />
<br />
|[广义高斯分布[广义高斯分布[广义高斯分布[广义高斯分布[广义高斯分布[广义高斯分布[广义高斯分布[广义高斯分布{\alpha}{2}\右)+\frac{\alpha}{2}</math>| |<math>(-infty,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[Pareto分布| Pareto]]| |<math>f(x)=\frac{\alpha x{m^\alpha}{x^{\alpha+1}</math>|{math>\ln\frac{x{m}{\alpha}+1+\frac{1}{\alpha}</math>|{math>[x{m,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[Student's t-distribution | Student's t]]| |<math>f(x)=\frac{(1+x^2/\nu)^{-\frac{\nu+1}{2}}}{\sqrt{\nu}B(\frac{1}{2},\frac{\nu 2})}</math>{!+\!1} {2}\左(\psi\左(\frac{\nu\)!+\!1} {2}\对)\!-\!\psi\左(\frac{\nu}{2}\右)\right)\!+\!\ln\sqrt{\nu}B\左(\frac{1}{2},\frac{\nu}{2}\右)</math>|</math>(\infty,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[三角分布|三角]]| |<math>f(x)=\begin{cases}<br />
<br />
\frac{2(x-a)}{(b-a)(c-a)}&\mathrm{for\}a\le x\leq c,\\[4pt]<br />
<br />
\frac{2(b-x)}{(b-a)(b-c)}&\mathrm{for\}c<x\le b,\\[4pt]<br />
<br />
\结束{cases}</math>|{math>\frac{1}{2}+\ln\frac{b-a}{2}</math>|{math>[0,1]\,</math><br />
<br />
|-<br />
<br />
|[[Weibull分布| Weibull]]| |<math>f(x)=\frac{k}{\lambda^k}x^{k-1}\exp\左(\frac{x^k}{\lambda^k}\右)</math>|{math>\frac{(k-1)\gamma E}{k}+\ln frac{\lambda}{k}+1</math>{math>[0,\infty)\,</math><br />
<br />
|-<br />
<br />
|[[多元正态分布|多元正态]]| |<数学><br />
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许多微分熵来自.<ref name=“lazorathie”>{引用期刊| author=Lazo,A.和P.Rathie | title=关于连续概率分布熵| journal=IEEE Transactions On Information Theory | year=1978 | volume=24 | issue=1 | doi=10.1109/TIT.1978.1055832 | pages=120–122}</ref>{rp | 120–122}<br />
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[[Category:熵和信息]]<br />
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[[Category:信息论]]<br />
[[Category:统计的随机性]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%9B%96%E4%BA%9A%E5%81%87%E8%AF%B4&diff=21964盖亚假说2021-02-24T05:35:36Z<p>Henry:</p>
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|description=盖亚假说认为,生物体与地球上的无机环境相互作用,形成一个协同和自我调节的复杂系统,有助于维持和延续地球上的生命条件。<br />
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[[File:The Earth seen from Apollo 17.jpg|thumb|对行星可居住性的研究主要基于对地球条件的了解进行推断,因为地球是目前已知的唯一一颗拥有生命的行星 ]]<br />
'''盖亚假说 Gaia hypothesis'''(又称'''盖亚理论 Gaia theory'''或'''盖亚原理 Gaia principle''')认为,生物体与地球上的无机环境相互作用,形成一个协同和自我调节的复杂系统,有助于维持和延续地球上的生命条件。<br />
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这个假设是由化学家詹姆斯·洛夫洛克 James Loveloc<ref name="J1972" />提出的,<ref name="lovelock1974">{{cite journal|last1=Lovelock|first1=J.E.|last2=Margulis|first2=L.|title=Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis|journal=Tellus|date=1974|volume=26|series=Series A|issue=1–2|pages=2–10|doi=10.1111/j.2153-3490.1974.tb01946.x|publisher=International Meteorological Institute|location=Stockholm|issn=1600-0870|ref=harv|bibcode=1974Tell...26....2L}}</ref>他以希腊神话中地球的化身盖亚的名字命名了这个想法。2006年,伦敦地质学会授予Lovelock沃拉斯顿勋章 Wollaston Medal,以表彰他在盖亚假说方面的工作。 <ref>{{cite web|title=Wollaston Award Lovelock|url=https://www.geolsoc.org.uk/About/History/Awards-Citations-Replies-2001-Onwards/2006-Awards-Citations-Replies|accessdate=19 October 2015}}</ref><br />
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与该假设有关的主题包括生物圈和生物体的进化如何影响全球温度的稳定性、海水的盐度、大气中的氧含量、液态水水圈的维持以及其他影响地球宜居性的环境变量。<br />
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盖亚假说最初被诟病为目的论、反对自然选择的原则,但后来的改进使盖亚假说与来自地球系统科学、生物地球化学和系统生态学等领域的观点相一致。<ref name="Turney, Jon 2003"/><ref name="Schwartzman2002">{{cite book |author=Schwartzman, David |title=Life, Temperature, and the Earth: The Self-Organizing Biosphere |publisher=Columbia University Press |date=2002 |isbn=978-0-231-10213-1 }}</ref><ref>Gribbin, John (1990), "Hothouse earth: The greenhouse effect and Gaia" (Weidenfeld & Nicolson)</ref>Loveloc还曾经描述过地球的“地球物理学”。.<ref name="agesofgaia">Lovelock, James, (1995) "The Ages of Gaia: A Biography of Our Living Earth" (W.W.Norton & Co)</ref>即便如此,盖亚假说仍然受到一些批评,今天许多科学家认为只有少数证据支持这一理论,或与现有的证据相矛盾。<ref name="kirchner2002">{{Citation |last= Kirchner |first = James W. |title =Toward a future for Gaia theory |journal=[[Climatic Change (journal)|Climatic Change]] |volume = 52 |issue = 4 |pages = 391–408 |date = 2002 | doi = 10.1023/a:1014237331082 }}</ref><ref name="volk2002">{{Citation |last= Volk |first = Tyler |title =The Gaia hypothesis: fact, theory, and wishful thinking |journal = Climatic Change |volume = 52 |issue = 4 |pages = 423–430 |date = 2002 | doi = 10.1023/a:1014218227825 }}</ref><ref name="beerling2007">{{cite book |last=Beerling |first=David |authorlink=David Beerling|date=2007 |title=The Emerald Planet: How plants changed Earth's history |url=http://ukcatalogue.oup.com/product/9780192806024.do |location=Oxford|publisher=Oxford University Press |page= |isbn= 978-0-19-280602-4 |accessdate= }}</ref><br />
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==概述==<br />
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盖亚假说认为,生物体与其环境共同进化。也就是说,生物“影响它们的非生物环境,而环境反过来又通过自然选择的过程影响生物群”。Lovelock(1995)在他的第二本书中提供了证据,展示了从早期嗜酸、产甲烷细菌的世界向今天支持更复杂生命的富氧大气的进化。<br />
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在《生物圈的定向进化: 生物地球化学选择还是盖亚? Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?》一书中,这一假说的简化版被称为“有影响力的盖亚 influential Gaia”<ref name=":02">{{Cite journal|last=Lapenis|first=Andrei G.|year=2002|title=Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?|url=|journal=The Professional Geographer|volume=54 |issue=3|pages=379–391|via=[Peer Reviewed Journal]|doi=10.1111/0033-0124.00337}}</ref>。Andrei G. Lapenis在这本书中指出生物影响着非生物世界的温度和大气等多个方面。这本书不是一个人的工作,而是一群俄罗斯科研人员的成果合并成这个通过同行评议的出版物。它通过“微观力量 micro-forces”<ref name=":02" />阐述了生命与环境的共同进化。<br />
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由于二十世纪苏联与西方国家存在隔阂,直到最近,在盖亚假说中引进重叠概念的早期苏联科学家才为西方科学界所熟知。<ref name=":02" /> 这些科学家包括Piotr Alekseevich Kropotkin,Rafail Vasil'evich Rizpolozhensky,Vladimir Ivanovich Vernadsky和Vladimir Alexandrovich Kostitzin。<br />
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盖亚假说认为,地球是一个自我调节的复杂系统,包括生物圈、大气层、水圈和土壤圈,作为一个进化的系统紧密结合在一起。这个假说认为,这个被称为盖亚的系统作为整体,寻求适合当代生命的物理和化学环境。<br />
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生物学家和地球科学家通常将平衡一个时期的特征的因素视为系统的无方向[[涌现属性]]或有目的行为;例如,由于每个物种都追求自身利益,它们的联合行动可能对环境变化产生抵消作用。反对这一观点的人有时会举出一些导致了巨大变化而非平衡的事件作为反例,例如在<font color="#ff8000">'''太古宙 Archean'''</font>末期和<font color="#ff8000">'''元古代 Proterozoic'''</font>时期开始时,地球大气从<font color="#ff8000">'''还原环境 reducing environment'''</font>转变为富含氧气。 <br />
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盖亚通过一个由生物群无意识操作的控制论反馈系统实现进化,在完全的内稳态中广泛获得稳定的可居住条件。地球表面的许多过程对生命的保障条件至关重要,这些过程依赖于生命形式,特别是微生物与无机元素的相互作用。这些过程建立了一个全球控制系统,由地球系统的全球热力学不平衡状态提供动力,调节地球表面温度、大气成分和海洋盐度。<br />
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一种不太被接受的假说声称生物圈的变化是通过[[超级有机体|生物体的协调]]来实现的,并通过[[内稳态 Superorganism]]来维持这些条件。在一些版本的[[盖亚哲学 Gaia philosophy]]中,所有的生命形式都是一个被称为“盖亚”的生命行星的一部分。在这种观点下,大气、海洋和地壳将是盖亚通过生物多样性进行干预的结果。 <br />
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以前在生物地球化学领域已经观察到受生命形式影响的行星内稳态的存在,而且地球系统科学等其他领域也在研究这一现象。盖亚假说的原创性依赖于这样一种观点: 即使地球或外部事件威胁到内稳态平衡,盖亚也会为了保持生命的最佳状态而积极追求这种平衡。<br />
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盖亚假说对[[深层生态学]]运动产生了影响。<ref>David Landis Barnhill, Roger S. Gottlieb (eds.), ''Deep Ecology and World Religions: New Essays on Sacred Ground'', SUNY Press, 2010, p. 32.</ref><br />
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==细节==<br />
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盖亚假说假设地球是一个自我调节的[[复杂系统]],包括生物圈、地球大气、水圈和土壤圈,作为一个进化系统紧密耦合。该假说认为,这个系统作为一个整体,称为盖亚,寻求一个最适合当代生活的物理和化学环境。<ref name="vanishing255">Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 255.</ref><br />
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自从地球上有生命以来,太阳提供的能量增加了25%到30%;然而,地球表面温度一直保持在适宜居住的水平上,不曾突破上限或是下限。Lovelock还假设,产甲烷菌在早期大气中产生了较高水平的甲烷,这与在石化烟雾中发现的成分相似,在某些方面与土卫六上的大气相似。研究表明,在休伦期 Huronian、斯图尔特期 Sturtian和马里诺/瓦朗格冰期 Marinoan/Varanger Ice Ages,“氧冲击”和甲烷含量降低导致世界几乎变成了一个坚实的“雪球”。这些时代是前显生宙生物圈完全拥有自我调节能力的证据。<br />
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盖亚通过一个[[控制论]][[反馈]]系统在生物群的无意识运作中实现进化,导致在完全的内稳态中广泛存在稳定的可居住条件。地球表面对生命条件至关重要的许多过程都依赖于生物,特别是微生物与无机元素的相互作用。这些过程建立了一个全球控制系统,调节地球的表面温度、大气组成和海洋盐度,其动力来自地球系统的全球热力学不平衡状态。<ref>Kleidon, Axel. ''How does the earth system generate and maintain thermodynamic disequilibrium and what does it imply for the future of the planet?''. Article submitted to the ''Philosophical Transactions of the Royal Society'' on Thu, 10 Mar 2011</ref><br />
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温室气体CO<sub>2</sub>的处理在维持地球温度在可居住范围内起着关键作用(解释详见下文)。<br />
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受生命形式影响的行星内稳态的存在,以前在[[生物地球化学 biogeochemistry]]领域就已被观察到,而且其他领域,如[[地球系统科学]]也在研究这种稳态。盖亚假说的独创性依赖于这样一种观点,即盖亚积极追求这种内平衡,以保持维护生命的最佳状态,即使是在地球或外部事件威胁它们的时候。<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 179. </ref><br />
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受盖亚假说的启发,CLAW 假说提出了一个在海洋生态系统和地球气候之间运行的反馈回路。该假说特别提出,产生二甲硫醚的浮游植物对气候变化有反应,这些反应导致了一个[[负反馈循环]],稳定了地球大气的温度。<br />
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===地球表面温度的调控===<br />
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[[File:All palaeotemps.png|thumb|480px|Rob Rohde's palaeotemperature graphs]]<br />
目前,人口的增加及其活动对环境的影响,例如温室气体的增加,可能导致环境中的负反馈成为正反馈。Lovelock表示,这可能会极大地加速全球变暖,但他后来又表示,这种影响也可能发生得更慢。<br />
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说明了在温室气体维持低于临界温度的过程中, CO<sub>2</sub>起着至关重要的作用。 <br />
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有人批评盖亚假说似乎需要有机体之间不切实际的群体选择与合作,为了回应这种批评,James Lovelock 和 Andrew Watson建立了一个数学模型---- '''雏菊世界 Daisyworld''',其中生态竞争支撑着地。<br />
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受到盖亚假说启发的[[CLAW假说]]提出了一个在海洋生态系统和地球气候之间运行的反馈。<ref name="CLAW87">{{cite journal |doi=10.1038/326655a0 |author1=Robert Jay Charlson|author2=James Lovelock|author3=Andreae, M. O. |author4=Warren, S. G. |title=Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate |journal=Nature |volume=326 |issue=6114 |pages=655–661 |date=1987 |bibcode=1987Natur.326..655C }}</ref> 假设具体提出,产生二甲基硫的特定浮游植物对<font color="#ff8000">'''气候作用力 climate forcing'''</font>的变化作出反应,这些反应导致[[负反馈]],从而稳定地球大气的温度。<br />
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雏菊世界调查了一个星球的能量预算,这个星球上生长着两种不同的植物,黑色雏菊和白色雏菊,这两种植物占据了星球表面的很大一部分。雏菊的颜色影响了地球的反照率,黑色的雏菊吸收更多的光线,使地球变暖,而白色的雏菊则反射更多的光线,使地球变冷。人们认为黑色雏菊在较低的温度下生长和繁殖最好,而白色雏菊则被认为在较高的温度下生长最好。当温度上升到接近白色雏菊所喜欢的温度时,白色雏菊繁殖率高于黑色雏菊,导致更大比例的白色表面,更多的阳光被反射,减少热量输入,最终使地球降温。相反,随着气温的下降,黑色雏菊繁殖率高于白色雏菊,吸收了更多的阳光,使地球变暖。因此,温度会收敛于两种植物繁殖率相等时对应温度的值。<br />
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目前,人口的增加及其活动对环境的影响,如[[温室气体]]的倍增,可能导致环境中的[[负反馈]]变成[[正反馈]]。Lovelock曾表示,这可能会带来一场'''盖亚的复仇'''<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, </ref>极度加速的全球变暖。<ref>Lovelock J., NBC News. [http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite Link] Published 23 April 2012, accessed 22 August 2012.</ref><br />
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Lovelock和Watson指出,在有限的条件下,如果太阳的能量输出发生变化,由于竞争产生的负反馈可以将地球温度稳定在支持生命存在的范围内,而没有生命的地球则会表现出巨大的温度波动。白色和黑色雏菊的百分比会不断变化,以保持植物繁殖率相等的温度值,使两种生命形式都能茁壮成长。<br />
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====雏菊世界模拟====<br />
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[[File:StandardDaisyWorldRun2color.gif|thumb|280px|Plots from a standard black and white [[Daisyworld]] simulation]]<br />
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有人认为,这些结果是可以预测的,因为Lovelock和Watson选择的例子产生了他们想要的答案。<br />
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有人批评盖亚假说似乎需要有机体之间不切实际的[[群体选择]]和进化合作,詹姆斯·洛夫洛克 James Lovelock和安德鲁·沃森 Andrew Watson开发了一个数学模型——雏菊世界 Daisyworld,其中生态竞争为基础行星温度调节。 <ref name="daisyworld">{{cite journal|date = 1983|title = Biological homeostasis of the global environment: the parable of Daisyworld|journal = Tellus|volume = 35B|pages = 286–9|bibcode = 1983TellB..35..284W|doi = 10.1111/j.1600-0889.1983.tb00031.x|last1 = Watson | first1= A.J. | last2= Lovelock | first2= J.E|issue = 4}}</ref><br />
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长期以来,海洋盐度一直保持在3.5% 左右。海洋环境中盐度的稳定性很重要,因为大多数细胞需要相当恒定的盐度,一般不能耐受超过5% 的盐度值。海洋盐度为何恒定是一个长期的奥秘,因为没有任何方法可以抵消来自河流的流入盐。最近有人提出,盐分也会洋中脊的热水喷口排出,因此盐度可能受到穿过炽热玄武岩的海水循环的强烈影响。然而,海水的组成离平衡还很远,如果没有有机过程的影响,很难解释这一事实。有一种解释认为,地球历史上盐滩的形成是盐度平衡的原因之一。据推测,这些盐滩是由细菌菌落产生的,它们在生命过程中固定离子和重金属。<br />
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盖亚假说认为,地球的大气组成是由于生命的存在而保持在动态稳定的状态。大气成分提供了支持现代生命的条件。大气中除惰性气体以外的所有大气气体,要么是由生物体产生的,要么是由生物体加工的。<br />
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地球大气层的稳定性不是化学平衡的结果。氧是一种活性化合物,最终会与地球大气层和地壳中的气体和矿物质结合。在大氧化事件开始之前,大约5000万年前,氧气才开始在大气中持续少量存在。自寒武纪以来,大气中氧浓度一直在大气体积的15% 至35% 之间波动。微量的甲烷(每年产生100,000吨)不适合存在,因为甲烷在氧气氛中是可燃的。<br />
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地球大气层中的干燥空气大致(按体积计算)含有78.09% 的氮气、20.95% 的氧气、0.93% 的氩气、0.039% 的二氧化碳以及少量的其他气体,包括甲烷。Lovelock最初推测,高于25% 的氧气浓度会增加森林大火和森林大火的发生频率。石炭纪和白垩纪煤系地质时期O2浓度确实超过了25%时,正是这一时期形成了火成木炭。这一结果支持了Lovelock 的论点。<br />
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Daisyworld研究了由两种不同类型的植物(黑色雏菊和白色雏菊)组成的行星的能量预算。这两种植物被认为占据了地表的很大一部分。雏菊的颜色影响着这个星球的[[反照率 albedo]],因此黑色雏菊吸收更多的光并温暖地球,而白色雏菊则反射更多的光并使地球降温。黑雏菊在较低温度下生长繁殖最好,而白雏菊在较高温度下生长繁殖最好。当温度上升到接近白色雏菊的最适生长温度时,白色雏菊的繁殖能力超过了黑色雏菊,导致白色表面的比例增大,更多的阳光被反射,减少了热量输入,最终使地球变冷。相反,随着温度的下降,黑雏菊的繁殖能力超过了白雏菊,吸收了更多的阳光,使地球变暖。因此,温度将收敛到两种植物繁殖率相等对应的温度值。 <br />
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Lovelock和Watson表明,在有限的条件范围内,如果太阳的能量输出发生变化,由于竞争而产生的[[负反馈]]可以将地球的温度稳定在支持生命的值上,而没有生命的行星则会出现大范围的温度波动。白雏菊和黑雏菊的比例会不断变化,以使温度保持在植物繁殖率相等的值,从而使两种生命形式都能茁壮成长。 <br />
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盖亚假说的科学家们把生物体参与碳循环看作是维持适合生命条件的复杂过程之一。火山活动是大气中二氧化碳的最重要的自然来源,而碳酸盐岩的沉淀是大气中二氧化碳最重要的去除途径。碳沉淀、溶解和固定受到土壤中细菌和植物根系的影响,这些细菌和植物根系可以改善气体循环,或者在珊瑚礁中,碳酸钙以固体的形式沉积在海底。碳酸钙被活的有机体用来制造含碳的结构和外壳。一旦死亡,生物体的外壳就会沉到海底,在那里它们产生白垩和石灰石的沉淀物。<br />
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有人认为,结果是可预测的,因为Lovelock和Watson选择的例子产生了他们想要的反应。 <ref>{{cite journal | doi = 10.1023/A:1023494111532 | date = 2003 | last1 = Kirchner | first1 = James W. | journal = Climatic Change | volume = 58 |issue=1–2| pages = 21–45 |title=The Gaia Hypothesis: Conjectures and Refutations | ref = harv}}</ref><br />
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其中一种是赫氏圆石藻,这是一种数量丰富的颗石藻类,也参与了云的形成。通过增加球石氟化物的寿命来补偿过量的CO<sub>2</sub>,增加了锁定在海底的CO<sub>2</sub>的数量。球石粉会增加云量,从而控制地表温度,有助于降低整个地球的温度,有利于地球上植物所必需的降水。近年来,大气中CO<sub>2</sub>浓度有所增加,有证据表明,海洋藻华的浓度也在增加。<br />
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===海洋盐度调节 ===<br />
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地衣和其他生物加速了岩石表面的风化,而岩石在土壤中的分解也加快了,这要归功于根、真菌、细菌和地下动物的活动。因此,二氧化碳从大气层流向土壤的过程是在生物的帮助下调节的。当大气中CO<sub>2</sub>水平升高时,温度升高,植物生长。这种生长会增加植物对二氧化碳的消耗,植物会将二氧化碳处理到土壤中,从大气中排出。<br />
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在很长一段时间内,海洋盐度一直保持在3.5%左右。<ref name=":0">{{Cite book|title=The Introduction to Ocean Sciences|last=Segar|first=Douglas|publisher=Library of Congress|year=2012|isbn=978-0-9857859-0-1|location=http://www.reefimages.com/oceans/SegarOcean3Chap05.pdf|pages=Chapter 5 3rd Edition|quote=|via=}}</ref>海洋环境中的盐度稳定性非常重要,因为大多数细胞需要相当恒定的盐度,并且通常不能耐受超过5%的盐度值。恒定的海洋盐度是一个长期存在的谜团,因为没有任何过程可以抵消河流中的盐流入。大洋中脊上的热水喷口会排出盐分,有人认为<ref name="Gorham19912">{{cite journal|last=Gorham|first=Eville|date=1 January 1991|title=Biogeochemistry: its origins and development|journal=Biogeochemistry|publisher=Kluwer Academic|volume=13|issue=3|pages=199–239|doi=10.1007/BF00002942|issn=1573-515X|ref=harv}}</ref>这说明盐分也会受到海水循环的强烈影响。然而,海水的组成远未达到平衡,如果没有有机过程的影响,很难解释这一事实。地球历史中盐滩的形成是一个常用的证据。据推测,这些盐滩是由在生命过程中固定离子和重金属的菌落产生的。<ref name=":0" /><br />
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在地球的生物地球化学过程中,源和汇是元素的运动。我们海洋中盐离子的组成是:钠(Na+)、氯(Cl-)、硫酸盐(SO42-)、镁(Mg2+)、钙(Ca2+)和钾(K+)。构成盐度的元素不易变化,是海水的一种保守属性。<ref name=":0" />有许多机制可以将盐度从颗粒形态改变为溶解形态,然后再返回。已知的钠(即盐)因为岩石的风化、侵蚀和溶解作用被输送到河流中并沉积到海洋中。 <br />
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地中海是盖亚的肾脏,由 KennethJ.Hsue在2001年发现的。地中海的“干涸”是肾功能正常的证据。早期的“肾功能”是在“白垩纪(南大西洋)、侏罗纪(墨西哥湾)、二叠纪-三叠纪(欧洲)、泥盆纪(加拿大)、寒武纪/前寒武纪(冈瓦纳)盐沼沉积时期进行的。” <ref>{{Cite web|url=http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/|title=Scientia Marina: List of Issues|last=http://www.webviva.com|first=Justino Martinez. Web Viva 2007|website=scimar.icm.csic.es|language=English|access-date=2017-02-04}}</ref><br />
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地球是一个完整的整体,一个有生命的存在,这个观念有着悠久的传统。神话中的盖亚是拟人化地球的原始希腊女神,是希腊版本的“自然母亲”。<br />
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===大气层的氧气调节===<br />
派祖母 PIE grandmother,或地球母亲。 James Lovelock根据小说家威廉·戈尔丁 William Golding的建议给他的假设起了这个名字,他当时和Lovelock住在同一个村子里(英国威尔特郡鲍尔查尔克)。Golding的建议是以Gea为基础的,Gea是希腊女神名字的另一种拼写,在地质学、地球物理和地球化学中,Gea是前缀。后来,博物学家和探险家亚历山大·冯·洪堡 Alexander von Humboldt认识到生物、气候和地壳的共同进化。他的远见卓识的声明在西方没有被广泛接受,几十年后,盖亚假说刚提出时同样受到了科学界的抵制。<br />
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[[File:Vostok 420ky 4curves insolation.jpg|thumb|280px|Levels of gases in the atmosphere in 420,000 years of ice core data from [[Vostok Station|Vostok, Antarctica research station]]. Current period is at the left.]]<br />
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同样在20世纪之交,现代环境伦理学发展的先驱、荒野保护运动的先驱奥尔多 · 利奥波德在他的生物中心或整体的土地伦理学中提出了一个有生命的地球。<br />
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盖亚假说指出,地球的大气成分由于生命的存在而保持在动态稳定的状态。<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 163.</ref>大气中除惰性气体以外的所有大气气体都是由生物体制造或加工而成。<br />
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地球大气的稳定性不是化学平衡造成的。氧气是一种活性化合物,最终会与地球大气层和地壳上的气体和矿物质结合。在大氧化事件开始前的5000万年,氧气才在大气中少量存在。<ref name=Anabar2007>{{Cite journal| last4 = Arnold| last6 = Creaser| last3 = Lyons| first1 = A. | first2 = Y.| last9 = Scott| last2 = Duan | first3 = T. | first4 = G.| last8 = Gordon | first5 = B. | first10 = J. | first6 = R.| last10 = Garvin | first7 = A.| last11 = Buick | first8 = G. | first11 = R. | first9 = C.| title = A whiff of oxygen before the great oxidation event?| journal = Science| volume = 317| issue = 5846| year = 2007| last7 = Kaufman| pages = 1903–1906| last5 = Kendall| pmid = 17901330| last1 = Anbar | doi = 10.1126/science.1140325|bibcode = 2007Sci...317.1903A }}</ref> 自寒武纪开始以来,大气氧浓度值一直在大气体积的15%到35%之间波动。甲烷的痕迹(每年产生10万吨)是不存在的,因为甲烷在氧气环境中是可燃的。<br />
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盖亚假说和环境运动的另一个影响来自于苏联和美利坚合众国之间太空竞赛。在20世纪60年代,第一批进入太空的人类可以看到地球作为一个整体的样子。1968年,宇航员威廉 · 安德斯在阿波罗8号任务期间拍摄的地出照片,通过总体效应成为全球生态运动的早期象征。<br />
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65年9月,Lovelock在加利福尼亚喷气推进实验室研究探测火星生命的方法时,开始定义由生物群落控制的自我调节地球的概念。第一篇提到它的论文是行星大气:与C.E.Giffin合著的与生命存在有关的成分和其他变化。一个主要的概念是,通过大气的化学成分可以在行星尺度上探测到生命。根据picdumidi天文台收集的数据,像火星或金星这样的行星,其大气层处于化学平衡状态。这种与地球大气的差异被认为是这些行星上没有生命的证据。 <br />
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Lovelock在1972年和1974年的期刊文章中提出了盖亚假说,并在1979年出版了一本畅销书,名为《寻找盖亚 The Quest for Gaia》 ,开始引起科学界和批判界的关注。<br />
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Lovelock首先将其称为地球反馈假说,解释氧气和甲烷等化学物质在地球大气中如何保持稳定浓度。Lovelock认为,在其他行星的大气层中探测这种组合,是一种相对便宜可靠的探测生命的方法。<br />
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后来出现了其他关系,例如海洋生物产生的硫和碘的数量与陆地生物所需的数量大致相同,这些都支持了这一假说。<br />
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地球大气中的干空气大约(按体积)包含78.09%氮,20.95%的氧,0.93%氩,0.039%二氧化碳,以及少量其他气体,包括甲烷。Lovelock最初推测,氧气浓度超过25%会增加森林火灾和火灾的发生率。最近在石炭纪和白垩纪煤系中火成木炭的研究(这两个地质时期O<sub>2</sub>浓度超过25%)支持了Lovelock的观点。<br />
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1971年,微生物学家 Lynn Margulis博士加入了 Lovelock 的行列,努力将最初的假设充实为科学证明的概念。Margulis贡献了她关于微生物如何影响大气层和地球表面不同层次的知识。这位美国生物学家也唤受到科学界的批评,因为她倡导真核细胞器起源的理论,以及她对美国共生发源学会的贡献——现在被接受了Margulis在她的书《共生星球 The Symbiotic Planet》中将最后八章用于描述盖亚。然而,她反对对盖亚的广泛拟人化,并强调盖亚“不是一个有机体” ,而是“有机体之间相互作用的一个新兴属性”。她将盖亚定义为“组成地球表面一个巨大生态系统的一系列相互作用的生态系统”。这本书最令人难忘的“口号”实际上是由Margulis的一个学生打趣说的: “从太空看,盖亚只是共生而已。”<br />
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===CO<sub>2</sub>处理===<br />
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盖亚的科学家认为,生物参与碳循环是维持适宜生命条件的复杂过程之一。地球大气中的二氧化碳最重要的自然来源是火山活动,而最重要的去除过程是碳酸盐岩的沉淀,溶液和固碳受土壤中的细菌和植物根系的影响,它们改善了气体循环,珊瑚礁中碳酸钙以固体形式沉积在海底。碳酸钙被生物用来制造含碳结构和贝壳。一旦死亡,这些生物的壳就会落到海底,在那里它们会产生白垩和石灰岩的沉积物。 <br />
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One of these organisms is ''[[Emiliania huxleyi]]'', an abundant [[coccolithophore]] [[algae]] which also has a role in the formation of [[cloud]]s.<ref name="Harding2006">{{cite book |author=Harding, Stephan |title=Animate Earth |publisher=Chelsea Green Publishing |date=2006 |pages=65 |isbn=978-1-933392-29-5 }}</ref> CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants.{{citation needed|date=July 2015}} Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean [[algal bloom]]s are also increasing.<ref>{{Cite web | date = 12 September 2007 | title = Interagency Report Says Harmful Algal Blooms Increasing | url = http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | url-status = dead | archiveurl = https://web.archive.org/web/20080209234239/http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | archivedate = 9 February 2008 }}</ref><br />
其中一种生物是埃米利安藻(Emiliania huxleyi),它是一种丰富的球虫藻类,也在云层的形成中发挥作用。过量的二氧化碳通过球虫寿命的增加得到补偿,增加了锁定在海底的二氧化碳量。球虫增加了云层覆盖,从而控制了地表温度,有助于冷却整个地球,并有利于陆地植物所需的降水。最近大气中的二氧化碳浓度增加了,有一些证据表明海洋藻类水华的浓度也在增加。<br />
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[[Lichen]] and other organisms accelerate the [[weathering]] of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
地衣和其他生物加速了地表岩石的风化,而由于根系、真菌、细菌和地下动物的活动,土壤中岩石的分解速度也更快。因此,在生物的帮助下,二氧化碳从大气到土壤的流动受到调节。当大气中的二氧化碳浓度升高时,温度升高,植物生长。这种生长带来了植物对二氧化碳的更高消耗,植物将二氧化碳加工到土壤中,将其从大气中去除。<br />
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==历史==<br />
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Lovelock谨慎地提出了盖亚假说的一个版本,这一版本中盖亚并不是有意地在她的环境中维持生命赖以生存的复杂平衡。看起来,盖亚假说“故意”行为的说法只是他那本广受欢迎的书中的一个比喻性陈述,并不是字面意义上的理解。这种对盖亚假说的新陈述更能为科学界所接受。在这次会议之后,大多数关于目的论的指责都停止了。<br />
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===先例===<br />
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[[File:NASA-Apollo8-Dec24-Earthrise.jpg|thumb|''[[Earthrise]]'' taken from [[Apollo 8]] on December 24, 1968]]<br />
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In the eighteenth century, as [[geology]] consolidated as a modern science, [[James Hutton]] maintained that geological and biological processes are interlinked.<ref name=CapraWeb>{{cite book |author=Capra, Fritjof |title=The web of life: a new scientific understanding of living systems |publisher=Anchor Books |location=Garden City, N.Y |date=1996 |page=[https://archive.org/details/weboflifenewscie00capr/page/23 23] |isbn=978-0-385-47675-1 |url=https://archive.org/details/weboflifenewscie00capr/page/23 }}</ref> Later, the [[naturalist]] and explorer [[Alexander von Humboldt]] recognized the coevolution of living organisms, climate, and Earth's crust.<ref name=CapraWeb /> In the twentieth century, [[Vladimir Vernadsky]] formulated a theory of Earth's development that is now one of the foundations of ecology. Vernadsky was a Ukrainian [[geochemist]] and was one of the first scientists to recognize that the oxygen, nitrogen, and carbon dioxide in the Earth's atmosphere result from biological processes. During the 1920s he published works arguing that living organisms could reshape the planet as surely as any physical force. Vernadsky was a pioneer of the scientific bases for the environmental sciences.<ref>S.R. Weart, 2003, ''The Discovery of Global Warming'', Cambridge, Harvard Press</ref> His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
在十八世纪,随着地质学作为一门现代科学的巩固,詹姆斯·赫顿坚持认为地质和生物过程是相互联系的。后来,博物学家兼探险家亚历山大·冯·洪堡(Alexander von Humboldt)认识到活的有机体、气候和地壳的共同进化。在二十世纪,弗拉基米尔·维尔纳德斯基提出了一个地球发展的理论,这个理论现在是生态学的基础之一。沃尔纳德斯基是乌克兰的地球化学家,也是最早认识到地球大气中的氧、氮和二氧化碳是生物过程的结果的科学家之一。在20世纪20年代,他发表了一些著作,认为生物可以像任何物理力量一样重塑地球。韦纳德斯基是环境科学科学科学基础的先驱。他的富有远见的声明在西方没有被广泛接受,几十年后,盖亚假说刚开始也同样受到了科学界的抵制。<br />
In the eighteenth century, as geology consolidated as a modern science, James Hutton maintained that geological and biological processes are interlinked.[34] Later, the naturalist and explorer Alexander von Humboldt recognized the coevolution of living organisms, climate, and Earth's crust.[34] In the twentieth century, Vladimir Vernadsky formulated a theory of Earth's development that is now one of the foundations of ecology. Vernadsky was a Ukrainian geochemist and was one of the first scientists to recognize that the oxygen, nitrogen, and carbon dioxide in the Earth's atmosphere result from biological processes. During the 1920s he published works arguing that living organisms could reshape the planet as surely as any physical force. Vernadsky was a pioneer of the scientific bases for the environmental sciences.[35] His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
在十八世纪,随着地质学作为一门现代科学的巩固,詹姆斯·赫顿坚持认为地质和生物过程是相互联系的。后来,博物学家兼探险家亚历山大·冯·洪堡(Alexander von Humboldt)认识到活的有机体、气候和地壳的共同进化。在二十世纪,弗拉基米尔·维尔纳德斯基提出了一个地球发展的理论,这个理论现在是生态学的基础之一。沃尔纳德斯基是乌克兰的地球化学家,也是最早认识到地球大气中的氧、氮和二氧化碳是生物过程的结果的科学家之一。在20世纪20年代,他发表了一些著作,认为生物可以像任何物理力量一样重塑地球。韦纳德斯基是环境科学科学科学基础的先驱。他的富有远见的声明在西方没有被广泛接受,几十年后,盖亚假说刚开始也同样受到了科学界的抵制。<br />
Also in the turn to the 20th century Aldo Leopold, pioneer in the development of modern environmental ethics and in the movement for wilderness conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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::It is at least not impossible to regard the earth's parts—soil, mountains, rivers, atmosphere etc,—as organs or parts of organs of a coordinated whole, each part with its definite function. And if we could see this whole, as a whole, through a great period of time, we might perceive not only organs with coordinated functions, but possibly also that process of consumption as replacement which in biology we call metabolism, or growth. In such case we would have all the visible attributes of a living thing, which we do not realize to be such because it is too big, and its life processes too slow.<br />
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::— Stephan Harding, Animate Earth.<ref>Harding, Stephan. ''Animate Earth Science, Intuition and Gaia''. Chelsea Green Publishing, 2006, p. 44.</ref><br />
同样在20世纪之交,现代环境伦理学发展和荒野保护运动的先驱奥尔多·利奥波德(Aldo Leopold)在其关于土地的生物中心或整体伦理学中提出了活地球的观点。把地球的土壤、山川、河流、大气等各部分视为一个协调整体的器官或器官的一部分,每一部分都有其特定的功能,这至少不是不可能的。如果我们能看到这个整体,作为一个整体,在很长的一段时间里,我们不仅可以看到具有协调功能的器官,而且可能还可以看到器官消耗的过程作为替代,在生物学上我们称之为新陈代谢,或生长。在这种情况下,我们将拥有一个生物的所有可见属性,我们没有意识到这一点,因为它太大,它的生命过程太慢。 - 斯蒂芬·哈丁,《地球动画》<br />
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盖亚假说和环境运动的另一个总体影响来自苏联和美利坚合众国之间太空竞赛的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球的整体面貌。1968年宇航员William Anders在Apollo 8任务期间拍摄的照片“地球升起”,通过概述效果成为全球生态运动的早期标志。<ref>[http://digitaljournalist.org/issue0309/lm11.html 100 Photographs that Changed the World by Life - The Digital Journalist]</ref><br />
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===假说提出===<br />
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[[File:James Lovelock in 2005.jpg|thumb|[[James Lovelock]], 2005]]<br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the [[Jet Propulsion Laboratory]] in California on methods of detecting [[life on Mars (planet)|life on Mars]].<ref name="Lovelock1965">{{cite journal | author = Lovelock, J.E. | date = 1965 | title = A physical basis for life detection experiments | journal = [[Nature (journal)|Nature]] | volume = 207 | issue = 7 | pages = 568–570 | doi = 10.1038/207568a0 | pmid=5883628|bibcode = 1965Natur.207..568L | ref = harv}}</ref><ref>{{Cite web |url=http://www.jameslovelock.org/page4.html |title=Geophysiology |access-date=2007-05-05 |archive-url=https://web.archive.org/web/20070506073502/http://www.jameslovelock.org/page4.html |archive-date=2007-05-06 |url-status=dead }}</ref> The first paper to mention it was ''Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life'', co-authored with C.E. Giffin.<ref>{{cite journal | author1 = Lovelock, J.E. | author2 = Giffin, C.E. | date = 1969 | title = Planetary Atmospheres: Compositional and other changes associated with the presence of Life | journal = Advances in the Astronautical Sciences | volume = 25 | pages = 179–193 | isbn = 978-0-87703-028-7 | ref = harv}}</ref> A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the [[Pic du Midi de Bigorre|Pic du Midi observatory]], planets like Mars or Venus had atmospheres in [[chemical equilibrium]]. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
洛夫洛克于1965年9月开始定义由生物群落控制的自我调节地球的概念,在加州喷气推进实验室研究探测火星生命的方法时,第一篇提到火星生命的论文是《行星大气:与生命存在相关的成分和其他变化》,与C.E.吉芬合著的一个主要概念是,可以通过大气的化学成分在行星范围内探测到生命。根据Pic du Midi天文台收集的数据,火星或金星等行星的大气层处于化学平衡状态。这种与地球大气层的差异被认为是这些行星上没有生命存在的证据。 <br />
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Lovelock formulated the ''Gaia Hypothesis'' in journal articles in 1972<ref name="J1972">{{cite journal | author = J. E. Lovelock | title = Gaia as seen through the atmosphere | date = 1972 | journal = [[Atmospheric Environment]] | volume = 6 | issue = 8 | pages = 579–580 | doi = 10.1016/0004-6981(72)90076-5 | ref = harv|bibcode = 1972AtmEn...6..579L }}</ref> and 1974,<ref name="lovelock1974" /> followed by a popularizing 1979 book ''Gaia: A new look at life on Earth''. An article in the ''[[New Scientist]]'' of February 6, 1975,<ref>Lovelock, John and Sidney Epton, (February 8, 1975). "The quest for Gaia". [https://books.google.com/books?id=pnV6UYEkU4YC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false New Scientist], p. 304.</ref> and a popular book length version of the hypothesis, published in 1979 as ''The Quest for Gaia'', began to attract scientific and critical attention.<br />
洛夫洛克在1972年和1974年的期刊文章中提出了盖亚假说,随后在1979年出版了一本普及的书《盖亚:地球生命的新面貌》。1975年2月6日《新科学家》上的一篇文章和1979年出版的《寻找盖亚》这本畅销书中的假设版本开始引起科学界和评论界的注意。<br />
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Lovelock called it first the Earth feedback hypothesis,<ref name="Lovelock01">Harding, Stephan. Animate Earth Science, Intuition and Gaia. Chelsea Green Publishing, 2006, p. 44. ISBN 1-933392-29-0</ref> and it was a way to explain the fact that combinations of chemicals including [[oxygen]] and [[methane]] persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
洛夫洛克首先称之为地球反馈假说,这是一种解释包括氧和甲烷在内的化学物质在地球大气中以稳定浓度存在这一事实的方法。洛夫洛克建议,在其他行星的大气层中探测这种组合是一种相对可靠且廉价的探测生命的方法。<br />
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[[File:Lynn Margulis.jpg|thumb|left|[[Lynn Margulis]]]]<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<ref>{{cite journal | first1=W.D. | last1=Hamilton | first2=T.M. | last2=Lenton | title=Spora and Gaia: how microbes fly with their clouds | journal=Ethology Ecology & Evolution | volume=10 | pages=1–16 | date=1998 | issue=1 | url=http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | format=PDF | doi=10.1080/08927014.1998.9522867 | ref=harv | url-status=dead | archiveurl=https://web.archive.org/web/20110723055017/http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | archivedate=2011-07-23 }}</ref><br />
后来,其他关系,如海洋生物产生的硫和碘的数量与陆地生物所需的数量大致相同,也有助于支持这一假设。<br />
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In 1971 [[microbiologist]] Dr. [[Lynn Margulis]] joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet.<ref name="Turney, Jon 2003">{{cite book |author=Turney, Jon |title=Lovelock and Gaia: Signs of Life |publisher=Icon Books |location=UK |date=2003 |isbn=978-1-84046-458-0 |url-access=registration |url=https://archive.org/details/lovelockgaiasign0000turn }}</ref> The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of [[eukaryote|eukaryotic]] [[organelle]]s and her contributions to the [[endosymbiotic theory]], nowadays accepted. Margulis dedicated the last of eight chapters in her book, ''The Symbiotic Planet'', to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
1971年,微生物学家林恩 马古拉斯博士加入了洛夫洛克,致力于将最初的假设充实到科学证明的概念中,这位美国生物学家对真核生物细胞器起源理论的倡导,以及她对内共生理论的贡献,也引起了科学界的批评。玛古利斯在她的书《共生星球》中把八章的最后一章献给了盖亚。然而,她反对盖亚的广泛拟人化,并强调盖亚“不是一个有机体”,而是“有机体间相互作用的一种新兴特性”。她将盖亚定义为“一系列相互作用的生态系统,它们构成了地球表面一个巨大的生态系统。句号”。这本书中最令人难忘的“口号”实际上是由一位玛古利斯的学生打趣的:“从太空看,盖亚只是共生体。”。 <br />
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James Lovelock called his first proposal the ''Gaia hypothesis'' but has also used the term ''Gaia theory''. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments<ref name="J1990">{{cite journal | author = J. E. Lovelock | title = Hands up for the Gaia hypothesis | date = 1990 | journal = [[Nature (journal)|Nature]] | volume = 344 | issue = 6262 | pages = 100–2 | doi = 10.1038/344100a0|bibcode = 1990Natur.344..100L | ref = harv}}</ref> and provided a number of useful predictions.<ref name="Volk2003">{{cite book |author=Volk, Tyler |title=Gaia's Body: Toward a Physiology of Earth |publisher=[[MIT Press]] |location=Cambridge, Massachusetts |date=2003 |isbn=978-0-262-72042-7 }}</ref> In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating.<ref name="vanishing255"/><br />
詹姆斯 洛夫洛克称他的第一个提议为盖亚假说,但也使用了盖亚理论一词。洛夫洛克说,最初的公式是基于观察,但仍然缺乏科学的解释。盖亚假说后来得到了许多科学实验的支持,并提供了许多有用的预测。事实上,更广泛的研究证明了最初的假说是错误的,因为不是生命本身,而是整个地球系统在起调节作用。 <br />
===第一次盖亚会议===<br />
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1985年,关于盖亚假说的第一次公开研讨会,“地球是一个活的有机体吗?”在马萨诸塞大学阿默斯特举行。<ref>{{cite news |last=Joseph |first=Lawrence E. |title=Britain's Whole Earth Guru |work=The New York Times Magazine |date=November 23, 1986 |url=https://www.nytimes.com/1986/11/23/magazine/britain-s-whole-earth-guru.html |accessdate=1 December 2013}}</ref> The principal sponsor was the [[National Audubon Society]]. Speakers included James Lovelock, [[George Wald]], [[Mary Catherine Bateson]], [[Lewis Thomas]], [[John Todd (Canadian biologist)|John Todd]], Donald Michael, [[Christopher Bird]], [[Thomas Berry]], [[David Abram]], [[Michael A. Cohen|Michael Cohen]], and William Fields. Some 500 people attended.<ref>Bunyard, Peter (1996), "Gaia in Action: Science of the Living Earth" (Floris Books)</ref><br />
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===第二次盖亚会议===<br />
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1988年,climatology和Stephen Schneider组织了一次美国地球物理联合会会议。关于盖亚假说的第一次查普曼会议 。<br />
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在会议的“哲学基础”会议上,David Abram谈到了隐喻在科学中的影响,盖亚假说提供了一种新的、可能改变游戏规则的隐喻,而James Kirchner则批评盖亚假说的不精确性。Kirchner声称,Lovelock和Margulis提出的盖亚假说不是一个,而是四个- <br />
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* 共同进化的盖亚 Coevolution Gaia:生命和环境是以耦合的方式进化的。基什内尔声称,这已经被科学界接受,并不是什么新鲜事。 <br />
* 自我平衡的盖亚 Homeostatic Gaia:生命维持着自然环境的稳定,这种稳定性使生命得以继续存在。 <br />
* 地球物理盖亚 Geophysics Gaia:盖亚假说引起了人们对地球物理周期的兴趣,因此导致了地球物理动力学中有趣的新研究。 <br />
* 优化盖亚 Optimising Gaia:盖亚塑造了地球,使之成为整个生命的最佳环境。基什内尔声称,这是不可测试的,因此是不科学的。 <br />
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Kirchner发现了两种选择“软弱的盖亚”断言,为了所有生命的繁衍,生命往往会使环境变得稳定根据基什内尔的说法,“强大的盖亚 Strong Gaia”断言,生命趋向于使环境稳定,“使”所有生命繁荣昌盛。基什内尔声称,强大的盖亚是不稳定的,因此不科学。 <ref>{{cite journal | bibcode=1989RvGeo..27..223K | doi = 10.1029/RG027i002p00223 | title=The Gaia hypothesis: Can it be tested? | date=1989 | last1=Kirchner | first1=James W. | journal=Reviews of Geophysics | volume=27 | issue=2 | pages=223 | ref=harv}}</ref><br />
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然而,Lovelock和其他支持盖亚假说的科学家,确实试图反驳这种说法,即这个假设是不科学的,因为不可能通过受控实验来检验它。例如,针对盖亚假说是目的论的指控,Lovelock和安德鲁·沃森提出了雏菊世界模型(及其修改作为反驳这些批评的证据。<ref name="daisyworld"/>Lovelock说,雏菊世界模型“证明了全球环境的自我调节可以通过不同方式改变当地环境的生活类型之间的竞争产生”。 <ref>{{cite journal | pmid=10968941 | date=2000 | last1=Lenton | first1=TM | last2=Lovelock | first2=JE |title=Daisyworld is Darwinian: Constraints on adaptation are important for planetary self-regulation | volume=206 | issue=1 | pages=109–14 | doi=10.1006/jtbi.2000.2105 | journal=Journal of Theoretical Biology | ref=harv}}</ref><br />
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Lovelock谨慎地提出了盖亚假说的一个版本,没有声称盖亚有意或有意识地维持着生命生存所需的复杂平衡。看来盖亚假说“故意”的行为是他最受欢迎的第一本书中的隐喻性陈述,并不是字面意思。盖亚假说的这一新说法更为科学界所接受。在这次会议之后,目的论的大多数指控都停止了。<br />
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===第三次盖亚会议===<br />
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到2000年6月23日在西班牙巴伦西亚举行的关于盖亚假说的第二届查普曼会议召开之时,<ref>{{cite news|last=Simón|first=Federico|title=GEOLOGÍA Enfoque multidisciplinar La hipótesis Gaia madura en Valencia con los últimos avances científicos|journal=El País|date=21 June 2000|url=http://elpais.com/diario/2000/06/21/futuro/961538404_850215.html|accessdate=1 December 2013|language=spanish}}</ref>情况发生了很大变化。与其讨论Gaian目的论观点或Gaia假设的“类型”,不如说是将特定的机制维持在基本的长期动态平衡上,而该机制是在重大的进化长期结构变化的框架内保持的。<br />
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主要问题是:<ref>{{cite web|title=General Information Chapman Conference on the Gaia Hypothesis University of Valencia Valencia, Spain June 19-23, 2000 (Monday through Friday) |url=http://www.agu.org/meetings/chapman/chapman_archive/cc00bcall.html |work=AGU Meetings |accessdate=7 January 2017 |author=American Geophysical Union }}</ref><br />
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# “被称为盖亚的全球生物地球化学/气候系统是如何随时间变化的?它的历史是什么?盖亚能在一个时间尺度上保持系统的稳定性,但在较长的时间尺度上仍能经历向量变化吗?如何利用地质记录来检验这些问题?” <br />
# “盖亚假说的结构是什么?反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由任何给定时间正在进行的任何学科研究实际确定的,还是有一组应该被视为最真实的部分来理解盖亚假说,即随着时间的推移包含进化中的有机体?盖亚系统的这些不同部分之间的反馈是什么?物质的接近封闭对盖亚作为全球生态系统的结构和生命的生产力意味着什么?” <br />
# “盖亚假说过程和现象的模型如何与现实联系起来,它们如何帮助解决和理解盖亚假说?雏菊世界的结果如何传递到真实世界?“雏菊”的主要候选对象是什么?我们是否找到雏菊对盖亚理论有意义吗?我们应该如何寻找雏菊,我们应该加强搜索?如何使用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖亚机制?” <br />
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1997年,Tyler Volk认为,盖亚系统几乎不可避免地会产生,这是朝着使熵产量最大化的远非平衡的状态演化的结果,Kleidon(2004)同意这样的说法:“自稳行为可以从与行星反照率相关的MEP状态中产生”;“……生物地球在MEP状态下的行为很可能导致地球系统在长时间尺度上的近稳态行为,正如盖亚假说所述”。Staley(2002)同样提出了“……一种基于更传统的达尔文原理 Darwinian principles的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文选择 Darwinian selection。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。 <br />
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===第四次盖亚会议===<br />
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第四届盖亚假说国际会议于2006年10月在乔治梅森大学阿灵顿分校举行,会议由北弗吉尼亚州公园管理局和其他机构赞助。 <ref>{{cite web|title=Gaia Theory Conference at George Mason University Law School|url=http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|accessdate=1 December 2013|author=Official Site of Arlington County Virginia|archive-url=https://web.archive.org/web/20131203043657/http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|archive-date=2013-12-03|url-status=dead}}</ref><br />
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NVRPA的首席自然学家Martin Ogle和长期以来的Gaia假设支持者组织了这次活动。Lynn Margulis是马萨诸塞州阿默斯特大学地球科学系的著名大学教授,长期以来一直倡导盖亚假说。其他发言人包括:纽约大学地球与环境科学计划的联合主任Tyler Volk;Donald Aitken Associates的负责人Donald Aitken博士;亨氏科学,经济与环境中心总裁Thomas Lovejoy博士;Robert Correll,美国气象学会大气政策计划高级研究员以及著名的环境伦理学家J. Baird Callicott。 <br />
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这次会议将盖亚假说作为一种科学和隐喻来探讨,以此来理解我们如何着手解决21世纪的问题,如气候变化和持续的环境破坏<br />
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==批评==<br />
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最初很少受到科学家的关注(从1969年到1977年),此后的一段时间里,最初的盖亚假说受到了许多科学家的批评,比如Ford Doolittle,<ref name=":1">{{Cite journal|last=Doolittle|first=W. F.|year=1981|title=Is Nature Really Motherly|url=|journal=The Coevolution Quarterly|volume=Spring|pages=58–63|via=}}</ref>Richard Dawkins<ref name=":2">{{Cite book|title=The Extended Phenotype: the Long Reach of the Gene|last=Dawkins|first=Richard|publisher=Oxford University Press|year=1982|isbn=978-0-19-286088-0|location=|pages=}}</ref>和Stephen Jay Gould。<ref name="ReferenceB">Turney, Jon. "Lovelock and Gaia: Signs of Life" (Revolutions in Science)</ref>Lovelock曾说过,因为他的假设是以希腊女神的名字命名的,<ref name="Lovelock01"/>盖亚假说被许多非教派的科学家解释为新宗教 neo-Pagan religion。特别是许多科学家还批评了他的畅销书《盖亚》中采用的方法,认为地球上的生命是目的论的,认为事物是有目的的,是有目的的。Lovelock在1990年回应这一批评时说:“在我们的著作中我们没有任何地方表达行星自我调节是有目的的,或涉及生物群的远见或计划。”<br />
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Stephen Jay Gould批评盖亚假说是“一种隐喻,而不是一种机制。”<ref name="Gould 1997">{{cite journal |author=Gould S.J. |title=Kropotkin was no crackpot |journal=Natural History |volume=106 |pages=12–21 |date=June 1997 |url=http://libcom.org/library/kropotkin-was-no-crackpot |ref=harv}}</ref>他想知道实现自我调节内稳态的实际机制。在为盖亚假说辩护时,大卫·艾布拉姆认为古尔德忽略了一个事实,即“机制”本身就是一个隐喻——尽管这是一个非常常见且常常未被人认识的隐喻——它使我们把自然和生命系统看作是从外部组织和建造的机器(而不是自动或自组织的)现象)。艾布拉姆认为,机械隐喻使我们忽视了生命实体的活动性或能动性,而盖亚假说的有机体隐喻强调了生物群和生物圈作为一个整体的能动性。<ref>Abram, D. (1988) "The Mechanical and the Organic: On the Impact of Metaphor in Science" in Scientists on Gaia, edited by Stephen Schneider and Penelope Boston, Cambridge, Massachusetts: MIT Press, 1991</ref><ref>{{cite web|url=http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |title=The Mechanical and the Organic |accessdate=August 27, 2012 |url-status=dead |archiveurl=https://web.archive.org/web/20120223165936/http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |archivedate=February 23, 2012 }}</ref>关于盖亚假说的因果关系,Lovelock认为没有单一的机制负责各种已知机制之间的联系可能永远不为人所知,这一点在其他生物学和生态学领域都是理所当然的,而具体的敌意是出于其他原因留给他自己的假设的。<ref name="Lovelock, James 2001">Lovelock, James (2001), ''Homage to Gaia: The Life of an Independent Scientist'' (Oxford University Press)</ref><br />
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除了澄清自己的语言和对生命形式的理解之外,Lovelock自己将大部分批评归咎于批评家对非线性数学缺乏理解,以及贪婪还原论的线性化形式,在这种形式中,所有事件都必须在事实发生之前立即归因于特定的原因。他还指出,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,有些自我调节的现象可能无法用数学解释。<ref name="Lovelock, James 2001"/><br />
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===自然选择和进化===<br />
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Lovelock提出,全球生物反馈机制可以通过自然选择而进化,他指出,为生存而改善环境的生物比那些破坏环境的生物做得更好。然而,在20世纪80年代早期,W. Ford Doolittle和Richard Dawkins分别反对盖亚假说的这一方面。Doolittle认为,单个生物体的基因组中没有任何东西能够提供Lovelock提出的反馈机制,因此盖亚假说没有提出任何合理的机制,是不科学的。<ref name=":1" />Dawkins同时指出,要使有机体协同行动,就需要有远见和计划,这与当前科学界对进化论的理解相悖。<ref name=":2" />和Doolittle一样,他也拒绝了反馈回路可以稳定系统的可能性。<br />
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Lynn Margulis,一位与Lovelock合作支持盖亚假说的微生物学家,在1999年指出,“Darwin的宏伟愿景没有错,只是不完整。Darwin(特别是他的追随者)强调个人之间对资源的直接竞争是主要的选择机制,他给人的印象是环境只是一个静态的竞技场”。她写道,地球大气、水圈和岩石圈的组成都是围绕着“设定点”来调节的,就像在体内平衡中一样,但是这些设定点会随着时间的推移而变化。<ref name="ReferenceA">Margulis, Lynn. Symbiotic Planet: A New Look At Evolution. Houston: Basic Book 1999</ref><br />
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进化生物学家W. D. Hamilton提出了盖亚哥白尼(Gaia Copernican)概念,并补充说将需要另一个牛顿来解释盖恩如何通过达尔文自然选择来进行自我调节。<ref name=vanish09>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, pp. 195-197. </ref> 最近,Ford Doolittle建立在他和Inkpen的《ITSNTS》提案中提出,<ref name="ITSNTS">Doolittle WF, Inkpen SA. Processes and patterns of interaction as units of selection: An introduction to ITSNTS thinking. [https://www.pnas.org/content/115/16/4006 PNAS April 17, 2018 115 (16)] 4006-4014 </ref>差异性持久性可以与自然选择在进化中的差异性复制起相似的作用,从而提供自然选择理论与盖亚假设之间的可能和解。<ref name="Darwinizing Gaia">Doolittle WF. Darwinizing Gaia. [https://doi.org/10.1016/j.jtbi.2017.02.015 Journal of Theoretical BiologyVolume 434], 7 December 2017, Pages 11-19 </ref><br />
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===21世纪的批评===<br />
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盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化 Climatic Change》杂志上都提出了反对意见。反对它的一个重要论点是在许多例子中,生命对环境产生了有害或不稳定的影响,而不是采取行动来调节它。<ref name="kirchner2002"/><ref name="volk2002"/>最近几本书批评了盖亚假说,譬如“盖亚假说缺乏明确的观察支持,并且有重大的理论困难”<ref>{{cite book |last=Waltham |first=David |authorlink=David Waltham |date=2014 |title=Lucky Planet: Why Earth is Exceptional – and What that Means for Life in the Universe |url=https://archive.org/details/luckyplanetwhyea0000walt |location= |publisher=Icon Books |page= |isbn=9781848316560 |accessdate= |url-access=registration }}</ref>“(盖亚假说)令人不安地徘徊在污点、隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在原有的背景中”“盖亚假说既没有进化论的支持,也没有地质记录的经验证据的支持。”<ref>{{cite book |last1=Cockell |first1=Charles |authorlink1=Charles Cockell |last2=Corfield |first2=Richard |last3=Dise |first3= Nancy |last4=Edwards |first4=Neil |last5=Harris |first5=Nigel |date=2008 |title= An Introduction to the Earth-Life System |url= http://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/palaeontology-and-life-history/introduction-earth-life-system |location=Cambridge (UK) |publisher= Cambridge University Press |page= |isbn= 9780521729536 |accessdate= }}</ref> CLAW假说<ref name="CLAW87" />最初被认为是盖亚直接反馈的一个潜在例子,后来被发现对云的理解不那么可信凝聚核已经得到了改善。<ref>{{Citation |last1= Quinn |first1=P.K. |last2= Bates |first2=T.S. |title =The case against climate regulation via oceanic phytoplankton sulphur emissions |journal =Nature |volume=480 |issue=7375 |pages =51–56 |date = 2011 |doi=10.1038/nature10580|bibcode = 2011Natur.480...51Q |pmid=22129724|url=https://zenodo.org/record/1233319 }}</ref>2009年,[[美狄亚假说]]提出:生命对行星的状况非常有害,这与盖亚假说直接相反。<ref>Peter Ward (2009), ''The Medea Hypothesis: Is Life on Earth Ultimately Self-Destructive?''</ref> <br />
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2013年,托比·泰瑞尔 Toby Tyrrell在一本书中对盖亚假说总结道:“我认为盖亚假说是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚假说的同时,我们也能欣赏到的独创性和广博的视野,认识到他大胆的概念有助于激发许多关于地球的新思想,并倡导一种研究地球的整体方法。”<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical洛夫洛克 Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=209 |isbn=9780691121581 |accessdate= }}</ref>在其他地方,他提出了自己的结论:“盖亚假说并不能精确地描述我们世界的运转机制。”<ref>{{Citation |last= Tyrrell |first = Toby |title =Gaia: the verdict is… |journal = New Scientist |volume = 220 |issue = 2940 |pages = 30–31 |date= 26 October 2013 |doi=10.1016/s0262-4079(13)62532-4}}</ref> 这种说法需要被理解为是指盖亚假说的“强大”和“温和”形式,生物群遵循的原则是使地球处于最佳状态(强度5)或有利于生命(强度4),或者它作为一种内稳态机制(强度3)。后者是Lovelock所提倡的盖亚假说的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚假说的两种较弱的形式:共同进化德盖亚假说和有影响力的盖亚假说,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚假说”一词是没有用的,两种形式已经被自然选择和适应过程所接受和解释。<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=208 |isbn=9780691121581 |accessdate= }}</ref><br />
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==参考文献==<br />
<references/><br />
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*{{cite book |author=Bondì, Roberto |title=Blu come un'arancia. Gaia tra mito e scienza |publisher=Prefazione di Enrico Bellone |location=Torino, Utet |date=2006 |isbn=978-88-02-07259-3 }}<br />
*{{cite book |author=Bondì, Roberto |title=Solo l'atomo ci può salvare. L'ambientalismo nuclearista di James Lovelock |publisher=Prefazione di Enrico Bellone |location=Torino, Utet |date=2007 |isbn=978-88-02-07704-8}}<br />
*{{cite book |author=Jaworski, Helan |title=Le Géon ou la Terre vivante |publisher=Librairie Gallimard |location=Paris |date=1928 }}<br />
*Lovelock, James. ''The Independent''. [https://web.archive.org/web/20060408121826/http://comment.independent.co.uk/commentators/article338830.ece The Earth is about to catch a morbid fever], 16 January 2006.<br />
*{{cite journal |author=Kleidon, Axel |title=Beyond Gaia: Thermodynamics of Life and Earth system functioning |journal=Climatic Change |volume=66 |issue=3 |pages=271–319 |date=2004 |doi=10.1023/B:CLIM.0000044616.34867.ec }}<br />
*{{cite book |author=Lovelock, James |date=1995 |title=The Ages of Gaia: A Biography of Our Living Earth |isbn=978-0-393-31239-3 |publisher=Norton |location=New York}}<br />
*{{cite book |author=Lovelock, James |date=2000 |title=Gaia: A New Look at Life on Earth |isbn=978-0-19-286218-1 |publisher=Oxford University Press |location=Oxford }}<br />
*{{cite book |author=Lovelock, James |date=2001 |title=Homage to Gaia: The Life of an Independent Scientist |isbn=978-0-19-860429-7 |publisher=Oxford University Press |location=Oxford |url-access=registration |url=https://archive.org/details/homagetogaialife0000love }}<br />
*Lovelock, James (2006), interviewed in ''How to think about science'', CBC Ideas (radio program), broadcast January 3, 2008. [http://www.cbc.ca/ideas/episodes/2009/01/02/how-to-think-about-science-part-1---24-listen/ Link]<br />
*{{cite book | author=Lovelock, James | title=The Revenge of Gaia: Why the Earth Is Fighting Back&nbsp;— and How We Can Still Save Humanity | publisher=Allen Lane | date=2007 | isbn=978-0-7139-9914-3 |location=Santa Barbara CA| title-link=The Revenge of Gaia }}<br />
*{{cite book | author=Lovelock, James | title=The Vanishing Face of Gaia: A Final Warning| publisher=Basic Books | date=2009 | isbn=978-0-465-01549-8 |location=New York, NY}}<br />
*{{cite book | author=Margulis, Lynn | title=Symbiotic Planet: A New Look at Evolution | publisher=Weidenfeld & Nicolson |location=London | date=1998 | isbn=978-0-297-81740-6}}<br />
*{{cite book |author=Marshall, Alan |title=The Unity of Nature: Wholeness and Disintegration in Ecology and Science |publisher=Imperial College Press |location=River Edge, N.J |date=2002 |isbn=978-1-86094-330-0 }}<br />
*{{cite journal |author=Staley M |title=Darwinian selection leads to Gaia |journal=J. Theor. Biol. |volume=218 |issue=1 |pages=35–46 |date=September 2002 |pmid=12297068 |doi=10.1006/jtbi.2002.3059 }}<br />
*{{cite book |author=Schneider, Stephen Henry |title=Scientists debate Gaia: the next century |publisher=MIT Press |location=Cambridge, Massachusetts |date=2004|isbn=978-0-262-19498-3 }}<br />
*{{cite book |author=Thomas, Lewis G. |title=The Lives of a Cell; Notes of a Biology Watcher |url=https://archive.org/details/livesofcellnotes00thomrich |url-access=registration |publisher=Viking Press|location=New York |date=1974 |isbn=978-0-670-43442-8 }}<br />
{{Refend}}<br />
<br />
==进一步阅读==<br />
* {{cite book |last1=Joseph |first1=Lawrence E. |title=Gaia: The Growth of an Idea |date=1990 |location=New York, N.Y. |publisher=St. Martin's Press |isbn=978-0-31-204318-6 |url=https://archive.org/details/gaia00lawr|url-access=registration }}<br />
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本中文词条由[[用户:Henry|Henry]]翻译,[[用户:三奇|三奇]]审校,[[用户:薄荷|薄荷]]欢迎在讨论页面留言。<br />
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'''本词条内容源自公开资料,遵守 CC3.0协议。'''<br />
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[[Category:控制论]]<br />
[[Category:生态学理论]]<br />
[[Category:气候变化反馈]]<br />
[[Category:生物地球化学]]<br />
[[Category:地球]]<br />
[[Category: 生物学假说]]<br />
[[Category:天文学假设]]<br />
[[Category:气象假说]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%87%8F%E5%AD%90%E7%BA%A0%E7%BC%A0&diff=21257量子纠缠2021-01-24T13:45:38Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Correlation between measurements of quantum subsystems, even when spatially separated}}<br />
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[[File:SPDC figure.png|right|thumb|275px|[[Spontaneous parametric down-conversion]] process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[[Spontaneous parametric down-conversion process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[自发参量下转换过程可以将光子分裂成具有相互垂直极化的 II 型光子对。]<br />
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{{Quantum mechanics|fundamentals}}<br />
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'''Quantum entanglement''' is a physical phenomenon that occurs when a pair or group of [[particle]]s are generated, interact, or share spatial proximity in a way such that the [[quantum state]] of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the [[principle of locality|disparity between classical and quantum physics]]: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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量子纠缠是一种物理现象,描述的是当一对或一组粒子被产生、相互作用或共享空间邻近性时(包括当粒子被大距离分离时),该对或该组粒子中的每个粒子的量子态都无法独立于其他粒子的态。量子纠缠是经典物理学和量子物理学之间差别悬殊的核心问题:纠缠是量子力学的一个主要特征,而经典力学却没有这种特征。<br />
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[[Measurement#Quantum mechanics|Measurements]] of [[physical properties]] such as [[position (vector)|position]], [[momentum]], [[spin (physics)|spin]], and [[polarization (waves)|polarization]] performed on entangled particles can, in some cases, be found to be perfectly [[correlated]]. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly [[paradox]]ical effects: any measurement of a property of a particle results in an irreversible [[wave function collapse]] of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a property of a particle results in an irreversible wave function collapse of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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在某些情况下,对纠缠粒子的位置、动量、自旋和偏振等物理性质的测量的结果可以是完全相关的。例如,如果一对纠缠粒子的产生使得它们的总自旋已知为零,并且我们发现一个粒子在第一个轴上具有顺时针自旋,那么在同一个轴上测量的另一个粒子的自旋将会是逆时针的。然而,这种行为产生了看似矛盾的效应:对粒子性质的任何测量都会导致该粒子的不可逆波函数崩溃,并将改变原来的量子态。在粒子纠缠的情况下,这样的测量将影响整个纠缠系统。<br />
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Such phenomena were the subject of a 1935 paper by [[Albert Einstein]], [[Boris Podolsky]], and [[Nathan Rosen]],<ref name="Einstein1935"><br />
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Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen, and several papers by Erwin Schrödinger shortly thereafter, describing what came to be known as the EPR paradox. Einstein and others considered such behavior to be impossible, as it violated the local realism view of causality (Einstein referring to it as "spooky action at a distance") and argued that the accepted formulation of quantum mechanics must therefore be incomplete.<br />
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这些现象是阿尔伯特·爱因斯坦、鲍里斯·波多尔斯基和纳森·罗森在1935年发表的一篇论文和埃尔文·薛定谔随后不久发表的几篇论文的主题,这些论文描述了后来的EPR悖论。爱因斯坦和其他人认为这样的行为是不可能的,因为它违反了因果关系的局部实在论观点(爱因斯坦称之为“远处的幽灵行为”),并认为量子力学的公认公式因此一定是不完整的。<br />
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{{cite journal|author=Einstein A, Podolsky B, Rosen N|last2=Podolsky|last3=Rosen|year=1935|title=Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?|journal=Phys. Rev.|volume=47|issue=10|pages=777–780|bibcode=1935PhRv...47..777E|doi=10.1103/PhysRev.47.777|doi-access=free}}<br />
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</ref> and several papers by [[Erwin Schrödinger]] shortly thereafter,<ref name="Schrödinger1935"><br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<br />
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然而,后来,量子力学的反直觉预测在实验上得到了验证。所谓的“无漏洞”钟试验已经进行,在这种试验中,粒子位置被分开,以光速进行的通信将花费更长的时间——在一次实验中比测量间隔长10000倍<br />
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|author=Schrödinger E<br />
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According to some interpretations of quantum mechanics, the effect of one measurement occurs instantly. Other interpretations which don't recognize wavefunction collapse dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces correlation between the measurements and that the mutual information between the entangled particles can be exploited, but that any transmission of information at faster-than-light speeds is impossible.<br />
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根据量子力学的一些解释,一次测量的效果是瞬间发生的。其他不承认波函数崩塌的解释则认为不存在任何“效应”。然而,所有的解释都同意,纠缠产生了测量之间的相关性,纠缠粒子之间的互信息可以被利用,但任何信息的传输速度都不可能超过光速。<br />
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|title=Discussion of probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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Quantum entanglement has been demonstrated experimentally with photons, neutrinos, electrons, molecules as large as buckyballs, and even small diamonds. The utilization of entanglement in communication, computation and quantum radar is a very active area of research and development.<br />
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量子纠缠已经在光子、中微子、电子、巴基球大小的分子,甚至小钻石的实验中得到证实。纠缠在通信、计算和量子雷达中的应用是一个非常活跃的研究和发展领域。<br />
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Article headline regarding the [[Einstein–Podolsky–Rosen paradox (EPR paradox) paper, in the May 4, 1935 issue of The New York Times.]]<br />
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文章标题关于[爱因斯坦-波多尔斯基-罗森悖论(EPR paradox)论文,发表于1935年5月4日的《纽约时报》]<br />
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|year=1935<br />
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|doi=10.1017/S0305004100013554<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.<br />
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1935年,阿尔伯特·爱因斯坦与鲍里斯·波多尔斯基和纳森·罗森在一篇联合论文中首次讨论了量子力学关于强关联系统的反直觉预测。 <br />
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|bibcode = 1935PCPS...31..555S }}</ref><ref name="Schrödinger1936"><br />
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{{cite journal |author=Schrödinger E<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated: Einstein later famously derided entanglement as "spukhafte Fernwirkung" or "spooky action at a distance."<br />
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此后不久,薛定谔发表了一篇影响深远的论文,定义并讨论了“纠缠”的概念在论文中,他承认了这个概念的重要性,并指出了爱因斯坦后来众所周知的对纠缠的嘲弄“幽灵般的超距作用”<br />
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|title=Probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously Bohm's interpretation of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when John Stewart Bell proved that one of their key assumptions, the principle of locality, as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是Bohm对量子力学的解释),但发表的其他工作相对较少。尽管如此,直到1964年,约翰·斯图尔特·贝尔(John Stewart Bell)证明了他们的一个关键假设,即应用于EPR所希望的隐变量解释的局部性原理,在数学上与量子理论的预测不一致,EPR的论点中的弱点至此才被发现。<br />
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|volume=32<br />
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|issue=3<br />
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Specifically, Bell demonstrated an upper limit, seen in Bell's inequality, regarding the strength of correlations that can be produced in any theory obeying local realism, and showed that quantum theory predicts violations of this limit for certain entangled systems. His inequality is experimentally testable, and there have been numerous relevant experiments, starting with the pioneering work of Stuart Freedman and John Clauser in 1972 and Alain Aspect's experiments in 1982. An early experimental breakthrough was due to Carl Kocher, Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles. Alain Aspect notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / superdeterminism loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<br />
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具体来说,贝尔证明了一个上限,可以在贝尔不等式中看到,关于遵循局部实在论的任何理论中可以产生的关联强度,并表明量子理论预测某些纠缠系统会违反这个极限。从1972年斯图亚特·弗里德曼和约翰·克劳瑟的开创性工作和1982年阿兰·阿斯佩的实验开始,他的不等式在实验上是可以检验的,并且存在许多相关的实验。早期的实验突破归功于卡尔·科彻,科彻的仪器配备了更好的偏振器,弗里德曼和克劳瑟使用了这种仪器,他们可以证实余弦平方依赖性,并用它来证明对一组固定角度的贝尔不等式的违反。阿兰·阿斯佩指出的则是“设置独立漏洞”——他称之为“牵强的”,然而,“不可忽视”的“剩余漏洞”——还没有被关闭,并且自由意志/超决定论的漏洞是无法弥补的;他说“没有任何实验,尽可能的理想情况,可以说是完全没有漏洞的。” <br />
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|pages=446–452<br />
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|year=1936<br />
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A minority opinion holds that although quantum mechanics is correct, there is no superluminal instantaneous action-at-a-distance between entangled particles once the particles are separated.<br />
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少数人认为,尽管量子力学是正确的,但是一旦粒子分离,纠缠的粒子之间并不存在超光速瞬时作用。<br />
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|doi=10.1017/S0305004100019137<br />
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|bibcode = 1936PCPS...32..446S }}<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of quantum key distribution protocols, most famously BB84 by Charles H. Bennett and Gilles Brassard and E91 by Artur Ekert. Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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贝尔的工作提出了利用这些超强相关性作为交流资源的可能性。它导致了1984年量子密钥分配协议的发现,其中最著名的是查尔斯·H·班纳特和吉尔斯 布拉萨德的BB84和艾特 艾克特的E91。虽然BB84不使用纠缠,但是艾克特的协议使用了对Bell不等式的违反作为安全性的证明。 <br />
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</ref> describing what came to be known as the [[EPR paradox]]. Einstein and others considered such behavior to be impossible, as it violated the [[local realism]] view of causality (Einstein referring to it as "spooky [[action at a distance]]")<ref>Physicist John Bell depicts the Einstein camp in this debate in his article entitled "Bertlmann's socks and the nature of reality", p. 143 of ''Speakable and unspeakable in quantum mechanics'': "For EPR that would be an unthinkable 'spooky action at a distance'. To avoid such action at a distance they have to attribute, to the space-time regions in question, real properties in advance of observation, correlated properties, which predetermine the outcomes of these particular observations. Since these real properties, fixed in advance of observation, are not contained in quantum formalism, that formalism for EPR is incomplete. It may be correct, as far as it goes, but the usual quantum formalism cannot be the whole story." And again on p. 144 Bell says: "Einstein had no difficulty accepting that affairs in different places could be correlated. What he could not accept was that an intervention at one place could influence, immediately, affairs at the other." Downloaded 5 July 2011 from {{cite book |year=1987 |accessdate=2014-06-14 |title=Speakable and Unspeakable in Quantum Mechanics |first=J. S. |last=Bell |publisher=[[CERN]] |isbn=0521334950 |url=http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20150412044550/http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |archivedate=12 April 2015 |df=dmy-all }}</ref> and argued that the accepted formulation of [[quantum mechanics]] must therefore be incomplete.<br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally<ref name=":0" /><ref name=":1" /><ref name=":2" /> in tests in which polarization or spin of entangled particles were measured at separate locations, statistically violating [[Bell's inequality]]. In earlier tests, it couldn't be absolutely ruled out that the test result at one point could have been [[Loopholes in Bell test experiments|subtly transmitted]] to the remote point, affecting the outcome at the second location.<ref name=":2">Francis, Matthew.<br />
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[https://arstechnica.com/science/2012/10/quantum-entanglement-shows-that-reality-cant-be-local/ Quantum entanglement shows that reality can't be local], ''Ars Technica'', 30 October 2012</ref> However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<ref name=":1">{{cite journal|last1=Matson|first1=John|title=Quantum teleportation achieved over record distances|journal=Nature News|date=13 August 2012|doi=10.1038/nature.2012.11163|s2cid=124852641}}</ref><ref name=":0">{{cite journal<br />
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| title =Bounding the speed of 'spooky action at a distance<br />
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An entangled system is defined to be one whose quantum state cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or superposition, of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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一个纠缠系统被定义为一个量子态不能被分解为其局部成分的态的乘积的系统,也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部组分状态积的和或叠加;如果这个和必然有多个项,它就被纠缠。<br />
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| journal =Physical Review Letters |volume=110 | issue =26 |page=260407<br />
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| year =2013<br />
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Quantum systems can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on methods. Entanglement is broken when the entangled particles decohere through interaction with the environment; for example, when a measurement is made.<br />
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量子系统可以通过各种类型的相互作用而纠缠在一起。为了实验的目的,纠缠可以通过一些方法实现,请参见下面的方法部分。当纠缠的粒子通过与环境的相互作用而退离时,例如在进行测量时,纠缠就被打破了。 <br />
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| arxiv =1303.0614<br />
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| bibcode =2013PhRvL.110z0407Y<br />
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As an example of entanglement: a subatomic particle decays into an entangled pair of other particles. The decay events obey the various conservation laws, and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a spin-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be spin up on some axis, the other, when measured on the same axis, is always found to be spin down. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the singlet state.)<br />
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作为纠缠的一个例子:一个亚原子粒子衰变为一对纠缠的其他粒子。衰变事件遵循各种守恒定律,因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(以便总动量、角动量、能量等在此过程前后保持大致相同)。例如,一个自旋为零的粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量到自旋向上时,另一个粒子在同一个轴上被测量时,总是被发现是自旋向下。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于单线态)。<br />
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| doi = 10.1103/PhysRevLett.110.260407<br />
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| pmid =23848853 | last1 =Yin | first1 =Juan | last2 =Cao | first2 =Yuan | last3 =Yong | first3 =Hai-Lin | last4 =Ren | first4 =Ji-Gang | last5 =Liang | first5 =Hao | last6 =Liao | first6 =Sheng-Kai | last7 =Zhou | first7 =Fei | last8 =Liu | first8 =Chang | last9 =Wu | first9 =Yu-Ping | last10 =Pan | first10 =Ge-Sheng | last11 =Li | first11 =Li | last12 =Liu | first12 =Nai-Le | last13 =Zhang | first13 =Qiang | last14 =Peng | first14 =Cheng-Zhi | last15 =Pan | first15 =Jian-Wei | s2cid =119293698 }}</ref><br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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如果将这两种粒子分开,可以更好地观察到纠缠的特性。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫。现在,如果我们测量其中一个粒子的特性(比如自旋) ,得到一个结果,然后用同样的标准(沿着同样的轴自旋)测量另一个粒子,我们发现第二个粒子的测量结果将匹配(在补充意义上)第一个粒子的测量结果,因为它们的值将相反。<br />
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According to ''some'' [[interpretations of quantum mechanics]], the effect of one measurement occurs instantly. Other interpretations which don't recognize [[wavefunction collapse]] dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces ''[[correlation]]'' between the measurements and that the [[mutual information]] between the entangled particles can be exploited, but that any ''transmission'' of information at faster-than-light speeds is impossible.<ref>[[Roger Penrose]], ''The Road to Reality: A Complete Guide to the Laws of the Universe'', London, 2004, p. 603.</ref><ref name="Griffiths2004">{{citation | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |isbn= 978-0-13-111892-8}}</ref><br />
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根据“一些”[[量子力学的解释]],一次测量的效果瞬间发生。其他不承认[[波函数崩溃]]的解释则认为存在任何“效应”。然而,所有的解释都同意,纠缠在测量值之间产生了“[[相关]]”,并且纠缠粒子之间的[[互信息]]可以被利用,但是任何以高于光速的信息“传输”都是不可能的。 <br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a hidden variable theory (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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上述结果可能会或不会被认为是令人惊讶的。一个经典系统也会表现出同样的性质,而一个隐藏变量理论(见下文)肯定会被要求这样做,它建立在经典力学和量子力学的角动量守恒的基础上。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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Quantum entanglement has been demonstrated experimentally with [[photon]]s,<ref name="Kocher1">{{cite journal | doi = 10.1103/PhysRevLett.18.575 | volume=18 | issue=15 | title=Polarization Correlation of Photons Emitted in an Atomic Cascade | journal=Physical Review Letters | pages=575–577 | last1 = Kocher | first1 = CA | last2 = Commins | first2 = ED | year=1967| url=http://www.escholarship.org/uc/item/1kb7660q | bibcode=1967PhRvL..18..575K }}</ref><ref name="Kocherphd">Carl A. Kocher, Ph.D. Thesis (University of California at Berkeley, 1967). ''[https://escholarship.org/uc/item/1kb7660q Polarization Correlation of Photons Emitted in an Atomic Cascade]''</ref> [[neutrino]]s,<ref>J. A. Formaggio, D. I. Kaiser, M. M. Murskyj, and T. E. Weiss (2016), "[https://journals.aps.org/prl/accepted/6f072Y00C3318d41f5739ec7f83a9acf1ad67b002 Violation of the Leggett-Garg inequality in neutrino oscillations]". ''Phys. Rev. Lett.'' Accepted 23 June 2016.</ref> [[electron]]s,<ref name="NTR-20151021">{{cite journal |author=Hensen, B. |title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres |date=21 October 2015 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature15759 |display-authors=etal |volume=526 |issue=7575 |pages=682–686|bibcode = 2015Natur.526..682H |pmid=26503041|arxiv=1508.05949 |hdl=2117/79298 |s2cid=205246446 }} See also [http://www.nature.com/articles/nature15759.epdf?referrer_access_token=1QB20mTNTZW60nEXil0D79RgN0jAjWel9jnR3ZoTv0Pfu6MWINxm4Io03p2jIRZ8qX_3I3N0Kr-AlItuikCZOJrG8QbdRRghlecFwmixlbQpWuw1dtaib4Le5DQOG3u_aXHU85x1JEhOcQTa1sHi0yvW23bblxmEQZAmHL4G0gIVusG_6JWorroY5BprgbTl4FiaE8WltEgMoUMZfZBkEfbMcFDp5iR112TFx_x3ZRj88Wa23E2moEvTfKjtlued0&tracking_referrer=www.nytimes.com free online access version].</ref><ref name="NYT-20151021">{{cite news |last=Markoff |first=Jack |title=Sorry, Einstein. Quantum Study Suggests 'Spooky Action' Is Real. |url=https://www.nytimes.com/2015/10/22/science/quantum-theory-experiment-said-to-prove-spooky-interactions.html |date=21 October 2015 |work=The New York Times |accessdate=21 October 2015 }}</ref> [[molecule]]s as large as [[buckyball]]s,<ref>{{cite journal | doi = 10.1038/44348 | title = Wave–particle duality of C<sub>60</sub> molecules | date= 14 October 1999 | volume=401 | issue = 6754 | journal=Nature | pages=680–682 | pmid=18494170|bibcode = 1999Natur.401..680A | last1 = Arndt | first1 = M | last2 = Nairz | first2 = O | last3 = Vos-Andreae | first3 = J | last4 = Keller | first4 = C | last5 = van der Zouw | first5 = G | last6 = Zeilinger | first6 = A| s2cid = 4424892 }} {{subscription}}</ref><ref>[[Olaf Nairz]], [[Markus Arndt]], and [[Anton Zeilinger]], "Quantum interference experiments with large molecules", American Journal of Physics, 71 (April 2003) 319–325.</ref> and even small diamonds.<ref>{{cite journal |journal=Science |date=2 December 2011 |volume=334 |issue=6060 |pages=1253–1256 |doi=10.1126/science.1211914 |pmid=22144620 |url=http://www.sciencemag.org/content/334/6060/1253.full |title=Entangling macroscopic diamonds at room temperature |lay-url=https://www.newscientist.com/article/dn21235-entangled-diamonds-blur-quantumclassical-divide.html|bibcode = 2011Sci...334.1253L |last1=Lee |first1=K. C. |last2=Sprague |first2=M. R. |last3=Sussman |first3=B. J. |last4=Nunn |first4=J. |last5=Langford |first5=N. K. |last6=Jin |first6=X.- M. |last7=Champion |first7=T. |last8=Michelberger |first8=P. |last9=Reim |first9=K. F. |last10=England |first10=D. |last11=Jaksch |first11=D. |last12=Walmsley |first12=I. A. |s2cid=206536690 }}</ref><ref>[http://www.sciencemag.org/content/334/6060/1253/suppl/DC1 sciencemag.org], supplementary materials</ref> The utilization of entanglement in [[quantum communication|communication]], [[quantum computing|computation]] and [[quantum radar]] is a very active area of research and development.<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<br />
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矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能比光传播得快),因此确保纠缠对的另一部分的测量结果是“正确的”。在哥本哈根解释中,对其中一个粒子的自旋测量的结果是坍缩成一种状态,其中每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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== History 历史==<br />
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[[File:NYT May 4, 1935.jpg|right|thumb| 250px|Article headline regarding the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox) paper, in the May 4, 1935 issue of ''[[The New York Times]]''.]]<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, hence, any causal effect connecting the events would have to travel faster than light. According to the principles of special relativity, it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events and there are inertial frames in which is first and others in which is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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我们可以选择测量的距离和时间,以便使两次测量之间的间隔像空间一样,因此,连接事件的任何因果效应都必须比光传播得更快。根据狭义相对论的原理,任何信息都不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量值是第一个。对于两个分离的类空事件,存在惯性系,有惯性系在其中是第一位的,也有其他惯性系在其中是第一位的。因此,这两种测量之间的相关性不能解释为一种测量决定另一种测量:不同的观察者会对因果关系的作用产生分歧。<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by [[Albert Einstein]] in 1935, in a joint paper with [[Boris Podolsky]] and [[Nathan Rosen]].<ref name="Einstein1935"/><br />
1935年阿尔伯特 爱因斯坦与鲍里斯 波多斯基和纳兰 罗森在一篇联合论文中首次讨论了关于强关联系统的量子力学的反直觉预测。 <br />
(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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(事实上,即使没有纠缠,也会出现类似的悖论:单个粒子的位置分布在空间上,两个试图在两个不同位置检测粒子的大范围分离的探测器必须立即获得适当的相关性,这样它们就不会同时检测到粒子。)<br />
In this study, the three formulated the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox), a [[thought experiment]] that attempted to show that [[quantum mechanics|quantum mechanical theory]] was [[Incompleteness of quantum physics|incomplete]]. They wrote: "We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete."<ref name="Einstein1935"/><br />
在这项研究中,三人提出了[[爱因斯坦-波多尔斯基-罗森悖论]](EPR悖论),一个[[思维实验]],试图证明[[量子力学|量子力学理论]]是[[量子物理的不完全性|不完全性]]。他们写道:“因此,我们被迫得出结论,波函数给出的物理实在的量子力学描述并不完整。” <br />
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However, the three scientists did not coin the word ''entanglement'', nor did they generalize the special properties of the state they considered. Following the EPR paper, [[Erwin Schrödinger]] wrote a letter to Einstein in [[German language|German]] in which he used the word ''Verschränkung'' (translated by himself as ''entanglement'') "to describe the correlations between two particles that interact and then separate, as in the EPR experiment."<ref name=MK>Kumar, M., ''Quantum'', Icon Books, 2009, p. 313.</ref><br />
然而,这三位科学家并没有创造“纠缠”这个词,也没有概括出他们所考虑的状态的特殊性质。在EPR论文发表之后,[[埃尔温·薛定谔]]用德语给爱因斯坦写了一封信,信中他用“Verschränkung”(他自己翻译为“纠缠”)一词来描述两个相互作用然后分离的粒子之间的关联,就像EPR实验中那样。” <br />
A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables". The state of the particles being measured contains some hidden variables, whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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解决这一悖论的一个可能办法是假设量子理论是不完整的,测量结果取决于预先确定的“隐藏变量”。被测粒子的状态包含一些隐藏的变量,这些变量的值从分离的那一刻起就有效地决定了自旋测量的结果。这就意味着每个粒子都携带着所需的全部信息,在测量时不需要从一个粒子传输到另一个粒子。爱因斯坦和其他人(见上一节)最初认为这是摆脱悖论的唯一途径,而公认的量子力学描述(带有随机测量结果)肯定是不完整的。<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated:<ref name="Schrödinger1935"/> "I would not call [entanglement] ''one'' but rather ''the'' characteristic trait of [[quantum mechanics]], the one that enforces its entire departure from [[Classical mechanics|classical]] lines of thought."<br />
此后不久,薛定谔发表了一篇开创性的论文,对“纠缠”的概念进行了定义和讨论。在论文中,他认识到了这个概念的重要性,并指出:“我不会将[纠缠]称为‘一’,而是称之为[量子力学]的‘特性’。”,它完全背离了[[经典力学|经典]]的思路。” <br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the local realist or hidden variables view were correct, the results would always satisfy Bell's inequality. A number of experiments have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists. When measurements of the entangled particles are made in moving relativistic reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<br />
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然而,当考虑沿不同轴的纠缠粒子自旋的测量时,局部隐变量理论是失败的。如果进行了大量成对的此类测量(在大量成对的纠缠粒子上),那么在统计上,如果局部现实主义或隐藏变量的观点是正确的,结果将始终满足贝尔不等式。大量的实验表明,贝尔不等式在实践中是不成立的。然而,在2015年之前,被物理学家群体认为是最关键的是所有这些实践都有漏洞问题,。当在运动的相对论参考系中对纠缠粒子进行测量时,每个测量(在它自己的相对论时间范围内)都发生在另一个之前,测量结果将保持相关。<br />
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Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the [[theory of relativity]].<ref>Alisa Bokulich, Gregg Jaeger, ''Philosophy of Quantum Information and Entanglement'', Cambridge University Press, 2010, xv.</ref> Einstein later famously derided entanglement as "''spukhafte Fernwirkung''"<ref name="spukhafte">Letter from Einstein to Max Born, 3 March 1947; ''The Born-Einstein Letters; Correspondence between Albert Einstein and Max and Hedwig Born from 1916 to 1955'', Walker, New York, 1971. (cited in {{citation | title = Quantum Entanglement and Communication Complexity (1998) | journal = SIAM J. Comput. | volume = 30 | issue = 6 | citeseerx = 10.1.1.20.8324 | author = M. P. Hobson |pages=1829–1841 | display-authors = etal | year = 1998 }})</ref> or "spooky [[Action at a distance (physics)|action at a distance]]."<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are incompatible in the sense that these measurements' maximum simultaneous precision is constrained by the uncertainty principle. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations, and thus entanglement is a fundamentally non-classical phenomenon.<br />
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沿不同轴线测量自旋的基本问题是,这些测量不可能同时具有确定的值——它们是不相容的,因为这些测量的最大同时精度受到不确定性原理的限制。这与经典物理学中的发现相反,在经典物理学中,任何数量的性质都可以以任意精度同时测量。从数学上证明了相容测量不能显示违反贝尔不等式的关联,因此纠缠是一个基本的非经典现象。<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously [[De Broglie–Bohm theory|Bohm's interpretation]] of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when [[John Stewart Bell]] proved that one of their key assumptions, the [[principle of locality]], as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是量子力学的[[De Broglie–Bohm 理论 | Bohm表达]]),但其他发表的著作相对较少。尽管有人对此感兴趣,但直到1964年,[[约翰·斯图尔特·贝尔]]证明了他们的一个关键假设,[[局域性原理]],即应用于EPR希望解释的隐藏变量,在数学上与量子理论的预测不一致时,EPR论点中的漏洞才被发现。<br />
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Entanglement is required to preserve the Uncertainty principle, as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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纠缠是保持不确定性原理所必需的,如 EPR 悖论所示。例如,假设一个高能光子衰变成一个电子/正电子对,然后测量电子的位置和正电子的动量。如果我们在物理描述中不允许纠缠,那么每个粒子的位置和动量就可以通过参考动量守恒来推导,这就违反了测不准原理。或者,如果我们要求不确定性原理保持真实,而仍然不允许在物理上描述对的纠缠,不确定性原理将会违反动量守恒定律,因为在位置和动量上强相关性是不可能的(也就是说,人们不能有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关)。--><br />
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Specifically, Bell demonstrated an upper limit, seen in [[Bell's inequality]], regarding the strength of correlations that can be produced in any theory obeying [[local realism]], and showed that quantum theory predicts violations of this limit for certain entangled systems.<ref>{{cite journal |author = J. S. Bell |title = On the Einstein-Poldolsky-Rosen paradox |journal = Physics Physique Физика |volume = 1 |issue = 3 |pages = 195–200 |year = 1964|doi = 10.1103/PhysicsPhysiqueFizika.1.195 |doi-access = free }}</ref> His inequality is experimentally testable, and there have been numerous [[Bell test experiments|relevant experiments]], starting with the pioneering work of [[Stuart Freedman]] and [[John Clauser]] in 1972<ref name="Clauser">{{cite journal|doi=10.1103/PhysRevLett.28.938|last1=Freedman|first1=Stuart J.|last2=Clauser|first2=John F.|title=Experimental Test of Local Hidden-Variable Theories|journal=Physical Review Letters |volume=28 |issue=14 |pages=938–941|year=1972 |bibcode=1972PhRvL..28..938F|url=https://escholarship.org/uc/item/2f18n5nk}}</ref> and [[Alain Aspect]]'s experiments in 1982.<ref>{{cite journal |author1=A. Aspect |author2=P. Grangier |author3=G. Roger |name-list-style=amp |title = Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell's Inequalities |journal = Physical Review Letters |volume = 49 |issue = 2 |pages = 91–94 |year = 1982 |doi = 10.1103/PhysRevLett.49.91 |bibcode=1982PhRvL..49...91A|doi-access = free }}</ref> An early experimental breakthrough was due to Carl Kocher,<ref name="Kocher1"/><ref name="Kocherphd"/> who already in 1967 presented an apparatus in which two photons successively emitted from a calcium atom were shown to be entangled – the first case of entangled visible light. The two photons passed diametrically positioned parallel polarizers with higher probability than classically predicted but with correlations in quantitative agreement with quantum mechanical calculations. He also showed that the correlation varied only upon (as cosine square of) the angle between the polarizer settings<ref name="Kocherphd"/> and decreased exponentially with time lag between emitted photons.<ref name="Kocher2">{{cite journal | doi = 10.1016/0003-4916(71)90159-X | volume=65 | issue=1 | title=Time correlations in the detection of successively emitted photons | journal=Annals of Physics | pages=1–18 | last1 = Kocher | first1 = CA | year=1971| bibcode=1971AnPhy..65....1K }}</ref> Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles.<ref name="Clauser"/> All these experiments have shown agreement with quantum mechanics rather than the principle of local realism.<br />
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For decades, each had left open at least one [[Loopholes in Bell test experiments|loophole]] by which it was possible to question the validity of the results. However, in 2015 an experiment was performed that simultaneously closed both the detection and locality loopholes, and was heralded as "loophole-free"; this experiment ruled out a large class of local realism theories with certainty.<ref name="hanson">{{cite journal|last1=Hanson|first1=Ronald|title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres|journal=Nature|volume=526|issue=7575|pages=682–686|doi=10.1038/nature15759|arxiv=1508.05949|bibcode = 2015Natur.526..682H|pmid=26503041|year=2015|s2cid=205246446}}</ref> [[Alain Aspect]] notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / ''[[superdeterminism]]'' loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<ref>{{Cite journal | title=Viewpoint: Closing the Door on Einstein and Bohr's Quantum Debate| journal=Physics| volume=8| date=2015-12-16| last1=Aspect| first1=Alain| page=123| doi=10.1103/physics.8.123| doi-access=free| bibcode=2015PhyOJ...8..123A}}</ref><br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time. The authors claimed that this result was achieved by entanglement swapping between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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在2012年和2013年的实验中,在时间上从未共存的光子之间产生了偏振关联。作者认为,这一结果是在测量了一对纠缠光子的偏振态后,通过两对纠缠光子之间的纠缠交换得到的,证明了量子非定域性不仅适用于空间,也适用于时间。 <br />
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A minority opinion holds that although quantum mechanics is correct, there is no [[faster-than-light|superluminal]] instantaneous action-at-a-distance between entangled particles once the particles are separated.<ref>{{Cite journal |doi = 10.1142/S0217979206034078|title = Correlations in Entangled States|journal = International Journal of Modern Physics B|volume = 20|issue = 11n13|pages = 1496–1503|year = 2006|last1 = Sanctuary|first1 = B. C|arxiv = quant-ph/0508238|bibcode = 2006IJMPB..20.1496S|s2cid = 119403050}}</ref><ref>{{Cite arxiv |eprint = quant-ph/0404011 |last1 = Yin |first1 = Juan |title = The Statistical Interpretation of Entangled States |last2 = Cao |first2 = Yuan |last3 = Yong |first3 = Hai-Lin |last4 = Ren |first4 = Ji-Gang |last5 = Liang |first5 = Hao |last6 = Liao |first6 = Sheng-Kai |last7 = Zhou |first7 = Fei |last8 = Liu |first8 = Chang |last9 = Wu |first9 = Yu-Ping |last10 = Pan |first10 = Ge-Sheng |last11 = Zhang |first11 = Qiang |last12 = Peng |first12 = Cheng-Zhi |last13 = Pan |first13 = Jian-Wei |year = 2004 }}</ref><ref>{{cite journal|doi=10.1002/prop.201600044 | volume=65 | issue=6–8 | title=After Bell | year=2016 | journal=Fortschritte der Physik | page=1600044 | last1 = Khrennikov | first1 = Andrei}}</ref><ref>{{Cite journal |arxiv = 1603.08674|last1 = Yin|first1 = Juan|title = After Bell|journal = Fortschritte der Physik (Progress in Physics)|date=2017|volume = 65|issue = 1600014|pages = 6–8|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|bibcode = 2016arXiv160308674K}}</ref><ref>{{Cite journal |arxiv = quant-ph/0703251|last1 = Yin|first1 = Juan|title = Classical statistical distributions can violate Bell-type inequalities|journal = Journal of Physics A: Mathematical and Theoretical|volume = 41|issue = 8|pages = 085303|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|year = 2007|doi = 10.1088/1751-8113/41/8/085303|s2cid = 46193162}}</ref><br />
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In three independent experiments in 2013 it was shown that classically communicated separable quantum states can be used to carry entangled states. The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<br />
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2013年的三个独立实验表明,经典通信的可分离量子态可以用来携带纠缠态。第一次无漏洞贝尔试验于2015年在图代尔夫特举行,证实了贝尔不等式的不成立。 <br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of [[quantum key distribution]] protocols, most famously [[BB84]] by [[Charles H. Bennett (computer scientist)|Charles H. Bennett]] and [[Gilles Brassard]]<ref>C. H. Bennett and G. Brassard. "Quantum cryptography: Public key distribution and coin tossing". In ''Proceedings of IEEE International Conference on Computers, Systems and Signal Processing'', volume 175, p. 8. New York, 1984. http://researcher.watson.ibm.com/researcher/files/us-bennetc/BB84highest.pdf</ref> and [[E91 protocol|E91]] by [[Artur Ekert]].<ref>{{cite journal|last=Ekert|first=A.K.|authorlink=Artur Ekert|title=Quantum cryptography based on Bell's theorem|journal=Phys. Rev. Lett.|volume=67|issue=6|year=1991|doi=10.1103/PhysRevLett.67.661|issn=0031-9007|bibcode = 1991PhRvL..67..661E|pmid=10044956|pages=661–663}}</ref> Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<br />
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2014年8月,巴西研究人员加布里埃拉·巴雷托·莱莫斯和他的团队能够使用光子“拍摄”物体,这些光子并没有与实验对象发生相互作用,而是与这些物体发生了纠缠。来自维也纳大学的勒莫斯相信,这种新的量子成像技术可以在微光成像势在必行的领域找到应用,比如生物或医学成像。<br />
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== Concept 概念==<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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2015年,哈佛大学的马克斯·格雷纳团队直接测量了超冷玻色子原子系统中的Renyi纠缠。<br />
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=== Meaning of entanglement纠缠的意义 ===<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<br />
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从2016年起,IBM、微软等多家公司成功创建了量子计算机,并允许开发人员和技术爱好者公开实验量子力学的概念,这其中就包括量子纠缠。 <br />
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An entangled system is defined to be one whose [[quantum state]] cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or [[quantum superposition|superposition]], of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
纠缠系统被定义为其[[量子态]]不能被分解为其局部成分的态的乘积;也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部成分的状态积的和,或[[量子叠加|叠加]],如果这个和一定有一个以上的项,那么它是纠缠的。<br />
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Quantum [[physical system|systems]] can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on [[#Methods of creating entanglement|methods]]. Entanglement is broken when the entangled particles [[quantum decoherence|decohere]] through interaction with the environment; for example, when a measurement is made.<ref name="Peres1993">Asher Peres, ''[[Quantum Theory: Concepts and Methods]]'', Kluwer, 1993; {{ISBN|0-7923-2549-4}} p. 115.</ref><br />
量子[[物理系统|系统]]可以通过各种类型的相互作用而纠缠在一起。为了实验目的而实现纠缠的一些方法,请参见下面关于[[#创建纠缠的方法|方法]]的部分。当纠缠粒子通过与环境的相互作用[[量子退相干|退相干]]时,例如在进行测量时,纠缠将被打破。<br />
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There have been suggestions to look at the concept of time as an emergent phenomenon that is a side effect of quantum entanglement.<br />
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有人建议把时间的概念看作是量子纠缠的副作用的一种自然现象。<br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by Don Page and William Wootters in 1983.<br />
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换句话说,时间是一种纠缠现象,它将所有相等的时钟读数(正确准备的时钟或任何可用作时钟的物体的读数)放入同一个历史中。1983年,唐·佩奇和威廉·伍特斯首次提出了这一理论<br />
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As an example of entanglement: a [[subatomic particle]] [[Particle decay|decays]] into an entangled pair of other particles. The decay events obey the various [[conservation laws]], and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a [[Spin (physics)|spin]]-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be [[Spin (physics)#Direction|spin up]] on some axis, the other, when measured on the same axis, is always found to be [[Spin (physics)#Direction|spin down]]. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the [[singlet state]].)<br />
作为纠缠的一个例子:一个[[亚原子粒子]][[粒子衰变|衰变]]变成一对纠缠的其他粒子。衰变事件遵循各种[[守恒定律]],因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(因此总动量、角动量、能量等在此过程前后保持大致相同)。例如,[[自旋(物理)|自旋]]-零粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量为[[自旋(物理)方向|自旋向上]],另一个粒子在同一个轴上被测量时,总是被发现为[[自旋(物理)#方向|自旋向下]]。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于[[单态]]。)<br />
The Wheeler–DeWitt equation that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<br />
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20世纪60年代,惠勒-德威特方程引入了广义相对论和量子力学的概念,并于1983年再次引入,当时佩奇和伍特基于量子纠缠方程提出了一个解决方案。佩奇和伍特斯认为纠缠态可以用来测量时间。<br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
将这两个粒子分开,可以更好地观察到纠缠的特殊性质。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫(把这当成一个思维实验,而不是实际的实验)。现在,如果我们测量其中一个粒子的特定特性(例如,自旋),得到一个结果,然后使用相同的标准测量另一个粒子(沿相同的轴自旋),我们发现第二个粒子的测量结果将与第一个粒子的测量结果相匹配(在互补意义上)粒子,因为它们的值是相反的<br />
In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts. The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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2013年,在意大利都灵的国家理查尔卡计量研究所(INRIM) ,研究人员对佩奇和伍特的想法进行了首次实验测试。他们的结果被解释为证实了对于内部观察者来说时间是一种涌现的现象,但正如惠勒-德威特方程所预测的那样,对于宇宙的外部观察者来说时间是不存在的。纠缠的方法是从因果时间箭头的角度出发,假设一个粒子被测量的原因决定了另一个粒子测量结果的效应。<br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a [[hidden variable theory]] (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
上述结果可能会或不会被认为是令人惊讶的。一个经典系统将显示出相同的性质,而[[隐藏变量理论]](见下文)肯定需要这样做,基于经典和量子力学中的角动量守恒。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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===Paradox矛盾===<br />
Based on AdS/CFT correspondence, Mark Van Raamsdonk suggested that spacetime arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time. Induced gravity can emerge from the entanglement first law.<br />
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基于AdS/CFT对应关系, Mark Van Raamsdonk提出时空是量子自由度的一种涌现现象,量子自由度纠缠在时空的边界上。诱导引力可以从纠缠第一定律中产生。<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel [[faster than light]]) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the [[Copenhagen interpretation]], the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<ref>{{cite book|last1=Rupert W.|first1=Anderson|title=The Cosmic Compendium: Interstellar Travel|date=28 March 2015|publisher=The Cosmic Compendium|isbn=9781329022027|page=100|edition=First|url=https://books.google.com/books?id=JxauCQAAQBAJ&pg=PA100&lpg=PA100&dq=The+outcome+is+taken+to+be+random,+with+each+possibility+having+a+probability+of+50%25.+However,+if+both+spins+are+measured+along+the+same+axis,+they+are+found+to+be+anti-correlated.+This+means+that+the+random+outcome+of+the+measurement+made+on+one+particle+seems+to+have+been+transmitted+to+the+other,+so+that+it+can+make+the+%22right+choice%22+when+it+too+is+measured#v=onepage}}</ref><br />
矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能传播[[比光更快]]),从而确保纠缠对的另一部分的测量的“正确”结果。在[[哥本哈根解释]]中,其中一个粒子的自旋测量结果是坍缩成一种状态,在这种状态下,每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements [[spacelike]], hence, any causal effect connecting the events would have to travel faster than light. According to the principles of [[special relativity]], it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events {{math|''x''<sub>1</sub>}} and {{math|''x''<sub>2</sub>}} there are [[inertial frame]]s in which {{math|''x''<sub>1</sub>}} is first and others in which {{math|''x''<sub>2</sub>}} is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
可以选择测量的距离和时间,以便使两次测量之间的间隔[[类太空]],因此,任何与事件相关的因果效应都必须比光传播得更快。根据[[狭义相对论]]的原理,任何信息不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量值是第一个。对于两个类空分离事件{{math |''x'<sub>1</sub>}和{math |''x'<sub>2</sub>}存在[[惯性系]],其中{{math |''x'<sub>1</sub>}是第一个,而其他事件中{math |''x'<sub>2</sub>}是第一个。因此,这两种测量之间的相关性不能解释为一种测量决定另一种测量:不同的观察者会对因果关系的作用产生分歧。 <br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations. A well-known example is the Werner states that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables. Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<br />
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在媒体和大众科学中,量子非定域性常常被描述为与纠缠等价。虽然这对于纯二部量子态是正确的,但一般来说纠缠只对非局域关联是必要的,但是存在不产生这种关联的混合纠缠态。一个著名的例子是沃纳态,它纠缠在<math>p{sym}</math>的某些值上,但总是可以用局部隐藏变量来描述。此外,研究还表明,对于任意数目的当事方,存在真正纠缠但允许局部模型的态。<br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all distillable states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<br />
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上述关于局部模型存在性的证明假设一次只有一个量子态的副本可用。如果允许当事方对这些态的许多副本进行局部测量,那么许多明显的局部态(例如量子比特-沃纳态)就不能再由局部模型来描述。这尤其适用于所有蒸馏态。然而,当有足够多的拷贝时,所有的纠缠态是否都变成非局域态仍是一个悬而未决的问题。<br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
(事实上,即使没有纠缠,也会出现类似的悖论:单个粒子的位置分布在空间上,两个试图在两个不同位置检测粒子的大范围分离的探测器必须立即获得适当的相关性,这样它们就不会同时检测到粒子。)<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to quantum teleportation and to superdense coding, whereas non-locality is defined according to experimental statistics and is much more involved with the foundations and interpretations of quantum mechanics.<br />
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简言之,双方共享的一个状态的纠缠是必要的,但不足以使该状态成为非局部的。必须认识到,纠缠更普遍地被视为一个代数概念,因为它是非定域性、量子隐形传态和超密集编码的先决条件,而非定域性是根据实验统计定义的,它更多地涉及到量子力学的基础和解释。<br />
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=== Hidden variables theory 隐藏变量理论===<br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables".<ref>{{Cite news|url=https://www.scientificamerican.com/article/cosmic-test-bolsters-einsteins-ldquo-spooky-action-at-a-distance-rdquo/?WT.mc_id=SA_FB_PHYS_NEWS|title=Cosmic Test Bolsters Einstein's "Spooky Action at a Distance"|last=magazine|first=Elizabeth Gibney, Nature|newspaper=Scientific American|language=en|access-date=2017-02-04}}</ref> The state of the particles being measured contains some [[hidden-variable theory|hidden variables]], whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of quantum mechanics, including familiarity with the formalism and theoretical framework developed in the articles: bra–ket notation and mathematical formulation of quantum mechanics.<br />
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以下小节是为那些对量子力学的形式化、数学描述有良好工作知识的人准备的,包括熟悉文章中发展的形式主义和理论框架:bra–ket符号和量子力学的数学公式。<br />
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=== Violations of Bell's inequality 贝尔不等式的违反===<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the [[local realism|local realist]] or hidden variables view were correct, the results would always satisfy [[Bell's inequality]]. A [[Bell test experiments|number of experiments]] have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists.<ref>{{citation |author1=I. Gerhardt |author2=Q. Liu |author3=A. Lamas-Linares |author4=J. Skaar |author5=V. Scarani |author6=V. Makarov |author7=C. Kurtsiefer |year=2011 |title=Experimentally faking the violation of Bell's inequalities |journal=Phys. Rev. Lett. |volume=107 |issue=17 |page=170404 |arxiv=1106.3224 |doi=10.1103/PhysRevLett.107.170404 |bibcode=2011PhRvL.107q0404G |pmid=22107491|s2cid=16306493 }}</ref><ref>{{cite journal | last1 = Santos | first1 = E | year = 2004 | title = The failure to perform a loophole-free test of Bell's Inequality supports local realism | url = | journal = Foundations of Physics | volume = 34 | issue = 11| pages = 1643–1673 | doi=10.1007/s10701-004-1308-z|bibcode = 2004FoPh...34.1643S | s2cid = 123642560 }}</ref> When measurements of the entangled particles are made in moving [[special relativity|relativistic]] reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<ref>{{cite journal |author = H. Zbinden |title = Experimental test of nonlocal quantum correlations in relativistic configurations |journal = Phys. Rev. A |volume = 63 |issue = 2 |pages = 22111 |doi = 10.1103/PhysRevA.63.022111|year = 2001|arxiv = quant-ph/0007009 |bibcode = 2001PhRvA..63b2111Z |display-authors = 1 |last2 = Gisin |last3 = Tittel |s2cid = 44611890 |url = http://archive-ouverte.unige.ch/unige:37034 }}</ref><ref name=LG>Some of the history of both referenced Zbinden, et al. experiments is provided in Gilder, L., ''The Age of Entanglement'', Vintage Books, 2008, pp. 321–324.</ref><br />
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Consider two arbitrary quantum systems and , with respective Hilbert spaces and . The Hilbert space of the composite system is the tensor product<br />
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考虑两个任意的量子系统,分别用Hilbert空间和(?)。复合系统的Hilbert空间是张量积 <br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are [[Incompatible observables|incompatible]] in the sense that these measurements' maximum simultaneous precision is constrained by the [[uncertainty principle]]. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations,<ref>{{cite journal|last1=Cirel'son|first1=B. S.|title=Quantum generalizations of Bell's inequality|journal=Letters in Mathematical Physics|volume=4|issue=2|pages=93–100| year=1980|doi=10.1007/BF00417500|bibcode=1980LMaPh...4...93C|s2cid=120680226}}</ref> and thus entanglement is a fundamentally non-classical phenomenon.<br />
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<math> H_A \otimes H_B.</math><br />
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Entanglement is required to preserve the [[Uncertainty principle]], as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
纠缠是保持[[不确定性原理]]所必需的,如EPR悖论所示。例如,假设一个高能光子衰变成电子/正电子对,然后测量电子的位置和正电子的动量。如果在对的物理描述中不允许纠缠,那么每个粒子的位置和动量仍然可以通过动量守恒来推导,这违反了测不准原理。或者,如果我们要求测不准原理成立,并且仍然不允许在对的物理描述中纠缠,那么测不准原理将允许违反动量守恒定律,因为位置和动量之间的强相关性是不可能的(即人们无法有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关。--> <br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态 < math > scriptstyle | psi rangle _ a </math > ,而第二个系统处于状态 < math > scriptstyle | phi rangle _ b </math > ,则复合系统的状态为<br />
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=== Other types of experiments其他类型的试验 ===<br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time.<ref name="Xiao-song2012">{{cite journal |author=Xiao-song Ma, Stefan Zotter, Johannes Kofler, Rupert Ursin, Thomas Jennewein, Časlav Brukner & Anton Zeilinger |title=Experimental delayed-choice entanglement swapping |journal=Nature Physics |volume=8 |issue=6 |pages=480–485 |date=26 April 2012 |doi=10.1038/nphys2294|arxiv = 1203.4834 |bibcode = 2012NatPh...8..480M |last2=Zotter |last3=Kofler |last4=Ursin |last5=Jennewein |last6=Brukner |last7=Zeilinger |s2cid=119208488 }}</ref><ref>{{cite journal | last1 = Megidish | first1 = E. | last2 = Halevy | first2 = A. | last3 = Shacham | first3 = T. | last4 = Dvir | first4 = T. | last5 = Dovrat | first5 = L. | last6 = Eisenberg | first6 = H. S. | year = 2013 | title = Entanglement Swapping between Photons that have Never Coexisted | url = | journal = Physical Review Letters | volume = 110 | issue = 21| page = 210403| doi=10.1103/physrevlett.110.210403|arxiv = 1209.4191 |bibcode = 2013PhRvL.110u0403M | pmid=23745845| s2cid = 30063749 }}</ref> The authors claimed that this result was achieved by [[Quantum teleportation#Entanglement swapping|entanglement swapping]] between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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<math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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In three independent experiments in 2013 it was shown that [[classical physics|classically communicated]] [[separable state|separable quantum states]] can be used to carry entangled states.<ref>{{cite web|url=http://physicsworld.com/cws/article/news/2013/dec/11/classical-carrier-could-create-entanglement |title=Classical carrier could create entanglement |publisher=physicsworld.com |accessdate=2014-06-14|date=2013-12-11 }}</ref> The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<ref>{{cite web | url=http://hansonlab.tudelft.nl/loophole-free-bell-test/ | title=Loophole-free Bell test &#124; Ronald Hanson | access-date=24 October 2015 | archive-url=https://web.archive.org/web/20180704082456/http://hansonlab.tudelft.nl/loophole-free-bell-test/ | archive-date=4 July 2018 | url-status=dead }}</ref><br />
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States of the composite system that can be represented in this form are called separable states, or product states.<br />
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可以用这种形式表示的复合系统状态称为可分状态或乘积状态。<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<ref>{{Cite journal|url=http://www.nature.com/news/entangled-photons-make-a-picture-from-a-paradox-1.15781|title=Entangled photons make a picture from a paradox|journal=Nature|accessdate=13 October 2014|doi=10.1038/nature.2014.15781|year=2014|last1=Gibney|first1=Elizabeth|s2cid=124976589}}</ref><br />
2014年8月,巴西研究人员加布里埃拉·巴雷托·莱莫斯和他的团队能够用光子“拍摄”物体,这些光子并没有与受试者发生相互作用,而是与确实与这些物体发生相互作用的光子纠缠在一起。来自维也纳大学的莱莫斯相信,这种新的量子成像技术可以在生物或医学成像等领域的低光成像领域得到应用。<br />
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Not all states are separable states (and thus product states). Fix a basis <math>\scriptstyle \{|i \rangle_A\}</math> for and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for . The most general state in is of the form<br />
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并非所有的状态都是可分离的状态(因此产品状态也是如此)。修复的基础<math>\scriptstyle\{i\rangle\u a\}</math>,修复的基础<math>\scriptstyle\{j\rangle\u B\}</math>。最普遍的状态是 <br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
2015年,哈佛大学的马库斯 格瑞纳团队对超冷玻色子原子系统中的Renyi纠缠进行了直接测量。<br />
<math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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[数学] | psi rangle { AB } = sum { i,j } c { ij } | i rangle _ a otimes | j rangle _ b </math > 。<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<ref>{{Cite journal|last=Rozatkar|first=Gaurav|date=2018-08-16|title=Demonstration of quantum entanglement|url=https://osf.io/g8bpj/|journal=OSF|language=en}}</ref><br />
从2016年起,IBM、微软等多家公司成功创建了量子计算机,并允许开发人员和技术爱好者公开实验量子力学的概念,包括量子纠缠。<br />
This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > ,那么这种状态是可分的,因此 < math scriptstyle c { ij } = c ^ a _ ic ^ b _ j,</math > 产生 < math scriptstyle | psi rangle _ a = sum { i } c ^ a _ { i } | i } | i _ a </math > 和 < math > phi scriptstyle | b = sum { j } | j } | j rangle b = sum { j }。如果对于任何向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > 至少对于一对坐标 < math > scriptstyle c ^ a _ i,c ^ b _ j </math > 我们有 < math > scriptstyle c _ { ij } neq c ^ a _ ic ^ b _ j。如果一种状态是不可分割的,那么它被称为“纠缠态”。<br />
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=== Mystery of time 时间谜团===<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of , the following is an entangled state:<br />
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例如,给定两个基向量{ | 0 rangle _ a,| 1 rangle _ a } </math > 和两个基向量{ | 0 rangle _ b,| 1 rangle _ b } </math > ,下面是一个纠缠态:<br />
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There have been suggestions to look at the concept of time as an [[emergent phenomenon]] that is a side effect of quantum entanglement.<ref>{{Cite journal|title= Time from quantum entanglement: an experimental illustration|arxiv=1310.4691|bibcode = 2014PhRvA..89e2122M |doi = 10.1103/PhysRevA.89.052122|volume=89|issue= 5|pages=052122|journal=Physical Review A|year=2014 | last1 = Moreva | first1 = Ekaterina|s2cid=118638346}}</ref><ref>{{cite web|url=https://www.newscientist.com/article/dn24473-entangled-toy-universe-shows-time-may-be-an-illusion.html#.U8_-ApSSx2A|title=Entangled toy universe shows time may be an illusion|publisher=|accessdate=13 October 2014}}</ref><br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by [[Don Page (physicist)|Don Page]] and [[William Wootters]] in 1983.<ref>David Deutsch, The Beginning of infinity. Page 299</ref><br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right)<br />
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The [[Wheeler–DeWitt equation]] that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<ref name="medium.com">{{cite web|url=https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933|title=Quantum Experiment Shows How Time 'Emerges' from Entanglement|website=Medium|accessdate=13 October 2014|date=2013-10-23}}</ref><br />
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If the composite system is in this state, it is impossible to attribute to either system or system a definite pure state. Another way to say this is that while the von Neumann entropy of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry. The above example is one of four Bell states, which are (maximally) entangled pure states (pure states of the space, but which cannot be separated into pure states of each and ).<br />
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如果复合系统处于这种状态,就不可能把某个系统或某个系统归于一个确定的纯状态。另一种说法是,虽然整个状态的冯诺依曼熵为零(就像任何纯状态一样),但子系统的熵大于零。从这个意义上说,系统是“纠缠”的。这对干涉测量法有具体的经验影响。上面的例子是四个贝尔态中的一个,它们是(最大)纠缠纯态(空间的纯态,但不能分为每个和的纯态)。<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted{{by whom|date=August 2020}} to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts.<ref name="medium.com"/><br />
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2013年,在意大利都灵的国家计量研究所(INRIM),研究人员对佩奇和伍特斯的想法进行了首次实验测试。他们的结果被解释为{谁|日期=2020年8月}}证实了时间对于内部观察者来说是一种涌现的现象,而对于外部宇宙观察者来说则是不存在的,正如惠勒-德维特方程所预测的那样。<br />
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Now suppose Alice is an observer for system , and Bob is an observer for system . If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of , there are two possible outcomes, occurring with equal probability:<br />
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现在假设爱丽丝是系统的观察者,而鲍勃也是系统的观察者。如果在上面给出的纠缠态中,爱丽丝在[ | 0 rangle,| 1 rangle ] </math 本征基中进行测量,有两种可能的结果,发生的概率相等:<br />
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=== Source for the arrow of time时间之箭的来源 ===<br />
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Physicist [[Seth Lloyd]] says that [[quantum uncertainty]] gives rise to entanglement, the putative source of the [[arrow of time]]. According to Lloyd; "The arrow of time is an arrow of increasing correlations."<ref>{{Cite journal|url=https://www.wired.com/2014/04/quantum-theory-flow-time/|title=New Quantum Theory Could Explain the Flow of Time|journal=Wired|accessdate=13 October 2014|date=2014-04-25|last1=Wolchover|first1=Natalie}}</ref> The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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Alice 测量0,系统的状态崩溃为 < math > scriptstyle | 0 rangle _ a | 1 rangle _ b </math > 。<br />
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Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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Alice 测量1,系统的状态崩溃为 < math > scriptstyle | 1 rangle _ a | 0 rangle _ b </math > 。<br />
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=== Emergent gravity 涌现重力===<br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system has been altered by Alice performing a local measurement on system . This remains true even if the systems and are spatially separated. This is the foundation of the EPR paradox.<br />
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如果前者发生,那么 Bob 在相同基础上执行的任何后续测量都将返回1。如果出现后一种情况,(Alice 度量1) ,那么 Bob 的度量将确定返回0。因此,Alice 对系统进行了本地测量,从而对系统进行了更改。即使系统和空间上是分开的,这也是正确的。这就是 EPR 悖论的基础。<br />
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Based on [[AdS/CFT correspondence]], [[Mark Van Raamsdonk]] suggested that [[spacetime]] arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time.<ref>{{Cite journal|last=Van Raamsdonk|first=Mark|date=2010-06-19|title=Building up spacetime with quantum entanglement|journal=General Relativity and Gravitation|language=en|volume=42|issue=10|pages=2323–2329|doi=10.1007/s10714-010-1034-0|issn=0001-7701|arxiv=1005.3035|bibcode=2010GReGr..42.2323V}}</ref> [[Induced gravity]] can emerge from the entanglement first law.<ref>{{Cite journal|last1=Lee|first1=Jae-Weon|last2=Kim|first2=Hyeong-Chan|last3=Lee|first3=Jungjai|date=2013|title=Gravity from quantum information|journal=Journal of the Korean Physical Society|language=en|volume=63|issue=5|pages=1094–1098|doi=10.3938/jkps.63.1094|issn=0374-4884|arxiv=1001.5445|bibcode=2013JKPS...63.1094L|s2cid=118494859}}</ref><ref>{{cite arxiv|last1=Swingle|first1=Brian|last2=Van Raamsdonk|first2=Mark|date=2014-05-12|title=Universality of Gravity from Entanglement|eprint=1405.2933 |class=hep-th}}</ref><br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem.<br />
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爱丽丝的测量结果是随机的。Alice 不能决定将组合系统折叠到哪个状态,因此不能通过作用于她的系统将信息传递给 Bob。因此,在这个特定的方案中,因果关系被保留了下来。关于一般的论点,请参阅不交流定理。<br />
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== Non-locality and entanglement非定域性与纠缠 ==<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations.<ref name="Brunner-RMP2014">{{cite journal |title=Bell nonlocality |author1=Nicolas Brunner |author2=Daniel Cavalcanti |author3=Stefano Pironio |author4=Valerio Scarani |author5=Stephanie Wehner |journal=Rev. Mod. Phys. |volume=86 |issue=2 |pages=419–478 |date=2014 |doi=10.1103/RevModPhys.86.419 |arxiv=1303.2849|bibcode=2014RvMP...86..419B |s2cid=119194006 }}</ref> A well-known example is the [[Werner state]]s that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables.<ref name=werner1989>{{cite journal | last = Werner| first = R.F. | title = Quantum States with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model | journal = [[Physical Review A]] | volume = 40| pages = 4277–4281 | year = 1989 |doi=10.1103/PhysRevA.40.4277 | pmid=9902666 | issue=8|bibcode = 1989PhRvA..40.4277W }}</ref> Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<ref>{{cite journal|author=R. Augusiak, M. Demianowicz, J. Tura and A. Acín |title=Entanglement and Nonlocality are Inequivalent for Any Number of Parties |journal=Phys. Rev. Lett. |volume=115 |issue=3 |pages=030404 |year=2015 |arxiv=1407.3114 |doi=10.1103/PhysRevLett.115.030404|pmid=26230773 |hdl=2117/78836 |bibcode=2015PhRvL.115c0404A |s2cid=29758483 }}</ref><br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all [[entanglement distillation|distillable]] states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<ref>{{cite journal |title=Disproving the Peres conjecture: Bell nonlocality from bipartite bound entanglement |authors=Tamas Vértesi, Nicolas Brunner|year=2014 |journal=Nature Communications |volume=5 |issue=5297|page=5297 |doi=10.1038/ncomms6297 |pmid=25370352|arxiv=1405.4502 |s2cid=5135148}}</ref><br />
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As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a density matrix, which is a positive-semidefinite matrix, or a trace class when the state space is infinite-dimensional, and has trace 1. Again, by the spectral theorem, such a matrix takes the general form:<br />
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如上所述,量子系统的状态由希尔伯特空间中的单位向量给出。更一般地说,如果系统的信息较少,则称之为“系综”,并用密度矩阵来描述,密度矩阵是半正定矩阵,或当状态空间是无限维且有迹1时,用迹类来描述。同样,根据谱定理,这样的矩阵具有一般形式:<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to [[quantum teleportation]] and to [[superdense coding]], whereas non-locality is defined according to experimental statistics and is much more involved with the [[Quantum foundations|foundations]] and [[interpretations of quantum mechanics]].<ref>In the literature "non-locality" is sometimes used to characterize concepts that differ from the non-existence of a local hidden variable model, e.g., whether states can be distinguished by local measurements and which can occur also for non-entangled states (see, e.g., {{cite journal |authors=Charles H. Bennett, David P. DiVincenzo, Christopher A. Fuchs, Tal Mor, Eric Rains, Peter W. Shor, John A. Smolin, and William K. Wootters |title=Quantum nonlocality without entanglement |journal=Phys. Rev. A |volume=59 |issue=2 |pages=1070–1091 |year=1999 |doi=10.1103/PhysRevA.59.1070 |arxiv= quant-ph/9804053|bibcode=1999PhRvA..59.1070B |s2cid=15282650 }}). This non-standard use of the term is not discussed here.</ref><br />
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<math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
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== Quantum mechanical framework 量子力学框架==<br />
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where the w<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret as representing an ensemble where is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need density matrices to represent the state.<br />
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其中w<sub>i</sub>是正值概率(它们的总和为1),向量是单位向量,在无限维的情况下,我们将在迹范数中取这类状态的闭包。我们可以解释为表示一个集合,其中是状态为<math>| \alpha|i\rangle</math>的集合的比例。当一个混合态有秩1时,它就描述了一个“纯系综”。当一个量子系统的状态信息不足时,我们需要密度矩阵来表示这个状态。<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of [[quantum mechanics]], including familiarity with the formalism and theoretical framework developed in the articles: [[bra–ket notation]] and [[mathematical formulation of quantum mechanics]].<br />
以下小节适用于那些对[[量子力学]]的形式化、数学描述有良好工作知识的人,包括熟悉文章中开发的形式主义和理论框架:[[bra–ket符号]]和[[量子力学的数学公式]]。 <br />
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Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits electrons towards an observer. The electrons' Hilbert spaces are identical. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with spins aligned in the positive direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
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实验上,混合系综可以实现如下。考虑一个向观察者吐电子的“黑匣子”装置。电子的希尔伯特空间是相同的。这个装置可能产生所有处于相同状态的电子;在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以产生不同状态的电子。例如,它可以产生两个电子群:一个是自旋朝正方向排列的态<math>|\mathbf{z}+\rangle</math>,另一个是自旋朝负方向排列的态<math>|\mathbf{y}-\rangle</math>。一般来说,这是一个混合集合,因为可以有任意数量的总体,每个总体对应于不同的状态。 <br />
=== Pure states纯净态 ===<br />
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Consider two arbitrary quantum systems {{mvar|A}} and {{mvar|B}}, with respective [[Hilbert space]]s {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}. The Hilbert space of the composite system is the [[tensor product]]<br />
考虑两个任意量子系统{mvar | A}}和{mvar | B},分别具有[[希尔伯特空间]]s{mvar | H<sub>A</sub>}和{mvar | H<sub>B</sub>}。复合系统的Hilbert空间是[[张量积]] <br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on . That is, it has the general form<br />
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根据上面的定义,对于二部复合系统,混合态仅仅是上面的密度矩阵。也就是说,它有一般的形式<br />
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: <math> H_A \otimes H_B.</math><br />
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<math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
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[数学] rho = sum { i } w _ i 左[ sum _ { j } bar { c }{ ij }(| alpha _ { ij } rangle otimes | beta _ { ij } rangle)右]左[ sum _ k c _ { ik }(langle alpha _ ik } | otimes langle beta _ { ik } | 右]<br />
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</math><br />
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数学<br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态<math>\scriptstyle |\psi\rangle_A</math>,第二个系统处于状态<math>\scriptstyle |\phi\rangle_B</math>,则复合系统的状态为 <br />
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where the w<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
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其中w<sub>i</sub>是正值概率,<math>\sum|u j | c|ij}|^2=1</math>,向量是单位向量。这是自伴正的,有迹1。 <br />
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: <math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<br />
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从纯粹情形扩展可分性的定义,我们说混合状态是可分的,如果它可以写成<br />
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States of the composite system that can be represented in this form are called [[separable state]]s, or [[product state]]s.<br />
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可以用这种形式表示的复合系统的状态称为[[可分离状态]]s或[[产品状态]]。<br />
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<math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
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(数学) rho = sum i w i rho i ^ a times rho i ^ b,(数学)<br />
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Not all states are separable states (and thus product states). Fix a [[basis (linear algebra)|basis]] <math>\scriptstyle \{|i \rangle_A\}</math> for {{mvar|H<sub>A</sub>}} and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for {{mvar|H<sub>B</sub>}}. The most general state in {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} is of the form<br />
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where the are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems and respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
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其中为正值概率和<math>\rho i^A</math>和<math>\rho i^B</math>分别为子系统和上的混合态(密度算子)。换句话说,如果一个状态是不相关状态或乘积状态的概率分布,那么它是可分离的。通过将密度矩阵写成纯系综的和并展开,我们可以假定<math>\rho i^A</math>和<math>\rho i^B</math>本身就是纯系综。如果一个态是不可分离的,它就被称为纠缠态。<br />
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: <math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be NP-hard. For the and cases, a necessary and sufficient criterion for separability is given by the famous Positive Partial Transpose (PPT) condition.<br />
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一般来说,要判断一个混合态是否是纠缠态是很困难的。一般的二部格被证明是NP-困难的。对于和种情形,利用著名的正偏转子(PPT)条件给出了可分性的一个充要条件。<br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量<math>\scriptstyle[c^A\u i],[c^B\u j]</math>,则此状态是可分离的,因此<math>\scriptstyle c\u{ij}=c^A\u ic^B\u j,</math>产生<math>\scriptstyle |\psi\rangle | A=\sum{i}c^A{i}i\rangle | A</math>和<math>\scriptstyle |\phi\rangle | B=\sum{j}c^B{j\rangle B.</math>对于任何向量<math>\scriptstyle[c^A | i],[c^B | j]</math>至少对于一对坐标<math>\scriptstyle c^A | i,如果一个态是不可分的,它就叫做“纠缠态”<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of {{mvar|H<sub>A</sub>}} and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of {{mvar|H<sub>B</sub>}}, the following is an entangled state:<br />
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The idea of a reduced density matrix was introduced by Paul Dirac in 1930. Consider as above systems and each with a Hilbert space . Let the state of the composite system be<br />
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约化密度矩阵的概念是由保罗·狄拉克在1930年提出的。考虑以上系统,每个系统都有一个希尔伯特空间。设复合系统的状态为<br />
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<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
<br />
<math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
[数学] | Psi 在 h _ a 和 h _ b 之间。数学<br />
<br />
<br />
<br />
If the composite system is in this state, it is impossible to attribute to either system {{mvar|A}} or system {{mvar|B}} a definite [[pure state]]. Another way to say this is that while the [[von Neumann entropy]] of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry.<ref name="JaegerEtAl95">{{cite journal |author=Jaeger G, Shimony A, Vaidman L |title=Two Interferometric Complementarities |journal=Phys. Rev. |volume=51 |issue=1 |pages=54–67 |year=1995 |doi=10.1103/PhysRevA.51.54|pmid=9911555 |bibcode = 1995PhRvA..51...54J |last2=Shimony |last3=Vaidman }}</ref> The above example is one of four [[Bell states]], which are (maximally) entangled pure states (pure states of the {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} space, but which cannot be separated into pure states of each {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}).<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system . However, it still is possible to associate a density matrix. Let<br />
<br />
如上所述,通常没有办法将纯状态关联到组件系统。然而,仍然有可能将密度矩阵联系起来。让<br />
<br />
<br />
<br />
Now suppose Alice is an observer for system {{mvar|A}}, and Bob is an observer for system {{mvar|B}}. If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of {{mvar|A}}, there are two possible outcomes, occurring with equal probability:<ref name=nielchuang>{{cite book| last = Nielsen | first = Michael A. |author2=Chuang, Isaac L. | year = 2000 | title = Quantum Computation and Quantum Information | publisher = [[Cambridge University Press]] | pages = 112–113| isbn = 978-0-521-63503-5}}</ref><br />
<br />
<math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
<br />
<br />
<br />
# Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
Alice测量0,系统的状态将塌陷为<math>\scriptstyle | 0\rangle|A | 1\rangle|B</math> <br />
which is the projection operator onto this state. The state of is the partial trace of over the basis of system :<br />
<br />
也就是这个状态的投影操作符。状态是系统基础上的部分轨迹:<br />
<br />
# Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
Alice测量1,系统的状态将塌陷为<math>\scriptstyle | 1\rangle | A | 0\rangle | B</math>。 <br />
<br />
<br />
<math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
(| Psi rangle langle Psi | right) | j rangle b = hbox { Tr } _ b; rho _ t. </math > <br />
<br />
If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system {{mvar|B}} has been altered by Alice performing a local measurement on system {{mvar|A}}. This remains true even if the systems {{mvar|A}} and {{mvar|B}} are spatially separated. This is the foundation of the [[EPR paradox]].<br />
如果发生了前者,那么Bob在相同的基础上执行的任何后续测量都将始终返回1。如果出现后者,(Alice测量1),那么Bob的测量值肯定会返回0。因此,通过Alice对系统{mvar | a}执行本地测量,系统{mvar | B}已经改变。即使系统{mvar | A}}和{mvar | B}在空间上是分开的,这仍然是正确的。这是[EPR悖论]的基础。<br />
<br />
<br />
is sometimes called the reduced density matrix of on subsystem . Colloquially, we "trace out" system to obtain the reduced density matrix on .<br />
<br />
有时被称为子系统的约化密度矩阵。通俗地说,我们“追踪”系统,以获得约化密度矩阵。<br />
<br />
The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see [[no-communication theorem]].<br />
爱丽丝的测量结果是随机的。Alice无法决定将复合系统折叠到哪个状态,因此无法通过操作她的系统将信息传输给Bob。因此,在这个特殊的方案中,因果关系得以保留。关于一般的论点,请参见[[无通信定理]]。<br />
<br />
<br />
For example, the reduced density matrix of for the entangled state<br />
<br />
例如,纠缠态的约化密度矩阵<br />
<br />
=== Ensembles集成 ===<br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a [[density matrix]], which is a [[positive-semidefinite matrix]], or a [[trace class]] when the state space is infinite-dimensional, and has trace 1. Again, by the [[spectral theorem]], such a matrix takes the general form:<br />
如上所述,量子系统的状态由希尔伯特空间中的单位向量给出。更一般地说,如果系统的信息较少,则称之为“系综”,并用[[密度矩阵]]来描述,它是[[半正定矩阵]],或[[迹类]],当状态空间是无限维的,且有迹1时。同样,根据[[谱定理]],这样的矩阵具有一般形式: <br />
<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right) ,</math > <br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
discussed above is<br />
<br />
以上所讨论的是<br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors {{mvar| α<sub>i</sub>}} are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret {{mvar|ρ}} as representing an ensemble where {{mvar|w<sub>i</sub>}} is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need [[#Reduced density matrices|density matrices]] to represent the state.<br />
其中“w”<sub>i</sub>是正值概率(它们的总和为1),向量{mvar |α<sub>i</sub>}是单位向量,在无限维的情况下,我们将在迹范数中取这类状态的闭包。我们可以将{mvar |ρ}解释为表示一个系综,其中{mvar | w<sub>i</sub>}是状态为<math>\alpha\u i\rangle</math>的系综的比例。当一个混合态有秩1时,它就描述了一个“纯系综”。当一个量子系统的状态信息不足时,我们需要[[#约化密度矩阵|密度矩阵]]来表示这个状态。 <br />
<math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
左(| 0 rangle 0 | a + | 1 rangle 1 | a right) </math > <br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits [[electron]]s towards an observer. The electrons' Hilbert spaces are [[identical particles|identical]]. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with [[spin (physics)|spins]] aligned in the positive {{math|'''z'''}} direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative {{math|'''y'''}} direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
实验上,混合系综可以实现如下。考虑一个向观察者吐出[[电子]]s的“黑匣子”装置。电子的希尔伯特空间是[[相同粒子|相同]]。这个装置可能产生所有处于相同状态的电子;在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以产生不同状态的电子。例如,它可以产生两个电子群:一个电子群的态<math>|\mathbf{z}+\rangle</math>,[[spin(physics)| spins]]在正{{math |''z'}}方向对齐,另一个电子群的态<math>|\mathbf{y}-\rangle</math>,自旋在负{math |''y'}方向对齐。一般来说,这是一个混合集合,因为可以有任意数量的总体,每个总体对应于不同的状态。<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
这表明,正如预期的那样,一个纠缠纯系综的约化密度矩阵是一个混合系综。同样不足为奇的是,上面讨论的纯乘积态的密度矩阵<br />
<br />
<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}}. That is, it has the general form<br />
<br />
<math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
我不知道,但是我知道,我知道。<br />
<br />
<br />
<br />
: <math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
一般情况下,二体纯态 ρ 纠缠当且仅当其约化态是混合态而不是纯态。<br />
<br />
</math><br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
其中“w”<sub>i</sub>是正值概率,<math>\sum|u j | c|ij}|^2=1</math>,向量是单位向量。这是自伴正的,有迹1。<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional AKLT spin chain: the ground state can be divided into a block and an environment. The reduced density matrix of the block is proportional to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
在不同的基态自旋链中显式计算了约化密度矩阵。一维 AKLT 自旋链就是一个例子: 基态可以分为一个区块和一个环境。块的约化密度矩阵与另一个哈密顿量的简并基态成正比。<br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<ref name=Laloe>{{citation|last=Laloe|first=Franck|year=2001|title=Do We Really Understand Quantum Mechanics|journal=American Journal of Physics |volume=69 |issue=6|pages=655–701 |arxiv=quant-ph/0209123 |bibcode=2001AmJPh..69..655L |doi=10.1119/1.1356698}}</ref>{{rp|131–132}}<br />
<br />
The reduced density matrix also was evaluated for XY spin chains, where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence in this case.<br />
<br />
并对 XY 自旋链的全秩约化密度矩阵进行了计算。证明了在热力学极限中,大块自旋的约化密度矩阵的谱在这种情况下是一个精确的几何序列。<br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary quantum operations can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called LOCC (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<br />
<br />
在量子信息理论中,纠缠态被认为是一种“资源”,也就是说,生产成本高,可以实现有价值的转换。这种观点最明显的背景是“遥远的实验室”,即标记为“A”和“B”的两个量子系统,每个量子系统上都可以执行任意的量子操作,但它们之间没有量子力学的相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为局部操作和经典通信的操作。这些操作不允许在系统A和B之间产生纠缠态。但是如果A和B具有纠缠态的供应,那么这些操作与LOCC操作一起可以实现更大类别的变换。例如,a的一个量子位和B的一个量子位之间的相互作用可以通过首先将a的量子位传送到B,然后让它与B的量子位相互作用(现在是LOCC操作,因为两个量子位都在B的实验室里),然后将量子位传送回a来实现。在这个过程中,两个量子位的两个最大纠缠态被耗尽。因此,纠缠态是一种资源,能够在只有LOCC可用的情况下实现量子相互作用(或量子通道),但它们在过程中被消耗。在其他应用中,纠缠可以被视为一种资源,例如,私人通信或区分量子态。<br />
<br />
where the {{mvar|w<sub>i</sub>}} are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems {{mvar|A}} and {{mvar|B}} respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
其中,{mvar | w<sub>i</sub>}是正值概率,<math>\rho | i^A</math>和<math>\rho | i^B</math>分别是子系统{mvar | A}和{mvar | B}上的混合态(密度算子)。换句话说,如果一个状态是不相关状态或乘积状态的概率分布,那么它是可分离的。通过将密度矩阵写成纯系综的和并展开,我们可以假定<math>\rho i^A</math>和<math>\rho i^B</math>本身就是纯系综。如果一个态是不可分离的,它就被称为纠缠态<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be [[NP-hard]].<ref>{{Cite book |author=Gurvits L |title=Proceedings of the thirty-fifth ACM symposium on Theory of computing - STOC '03 |chapter=Classical deterministic complexity of Edmonds' Problem and quantum entanglement |journal=Proceedings of the Thirty-fifth Annual ACM Symposium on Theory of Computing |year=2003 |doi=10.1145/780542.780545 |page=10 |isbn=978-1-58113-674-6|arxiv=quant-ph/0303055 |s2cid=5745067 }}</ref> For the {{math|2 × 2}} and {{math|2 × 3}} cases, a necessary and sufficient criterion for separability is given by the famous [[Peres-Horodecki criterion|Positive Partial Transpose (PPT)]] condition.<ref>{{cite journal |author=Horodecki M, Horodecki P, Horodecki R |title=Separability of mixed states: necessary and sufficient conditions |journal=Physics Letters A |volume=223 |issue=1 |page=210 |year=1996 |doi=10.1016/S0375-9601(96)00706-2 |bibcode=1996PhLA..223....1H|arxiv = quant-ph/9605038 |last2=Horodecki |last3=Horodecki |citeseerx=10.1.1.252.496 |s2cid=10580997 }}</ref><br />
<br />
<br />
<br />
=== Reduced density matrices约化密度矩阵 ===<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
<br />
在这一节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的度量。<br />
<br />
The idea of a reduced density matrix was introduced by [[Paul Dirac]] in 1930.<ref>{{cite journal|doi=10.1017/S0305004100016108|title=Note on Exchange Phenomena in the Thomas Atom|year=2008|last1=Dirac|first1=P. A. M.|journal=Mathematical Proceedings of the Cambridge Philosophical Society| volume=26| issue=3|page=376|bibcode=1930PCPS...26..376D|url=https://www.cambridge.org/core/services/aop-cambridge-core/content/view/6C5FF7297CD96F49A8B8E9E3EA50E412/S0305004100016108a.pdf/div-class-title-note-on-exchange-phenomena-in-the-thomas-atom-div.pdf}}</ref> Consider as above systems {{mvar|A}} and {{mvar|B}} each with a Hilbert space {{mvar|H<sub>A</sub>, H<sub>B</sub>}}. Let the state of the composite system be<br />
<br />
<br />
<br />
: <math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.<br />
<br />
二分子2能级纯态的冯纽曼熵与本征值的图。当本征值为5时,冯纽曼熵处于最大值,相当于最大纠缠度。<br />
<br />
<br />
<br />
In classical information theory , the Shannon entropy, is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<br />
<br />
在经典的信息论中,香农熵,是与概率分布相关联的,如下:<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system {{mvar|A}}. However, it still is possible to associate a density matrix. Let<br />
如上所述,一般来说,无法将纯状态与组件系统{mvar | a}相关联。但是,仍然可以关联密度矩阵。让 <br />
<br />
<br />
<math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
<br />
[ math ] h (p _ 1,cdots,p _ n) =-sum _ i p _ i log _ 2 p _ i. [ math ]<br />
<br />
: <math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
<br />
<br />
Since a mixed state is a probability distribution over an ensemble, this leads naturally to the definition of the von Neumann entropy:<br />
<br />
由于混合状态是一个概率分布超过一个总体,这自然导致了冯纽曼熵的定义:<br />
<br />
which is the [[projection operator]] onto this state. The state of {{mvar|A}} is the [[partial trace]] of {{mvar|ρ<sub>T</sub>}} over the basis of system {{mvar|B}}:<br />
它是这个状态的[[投影操作符]]。{mvar | A}}的状态是{mvar |ρ<sub>T</sub>}在系统{mvar | B}基础上的[[部分迹]:<br />
<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
<br />
(rho) =-hbox { Tr } left (rho log _ 2{ rho } right) <br />
<br />
: <math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
<br />
<br />
In general, one uses the Borel functional calculus to calculate a non-polynomial function such as . If the nonnegative operator acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
<br />
一般来说,人们使用 Borel 函数演算来计算一个非多项式函数,如。如果非负算子作用于有限维希尔伯特空间,并且具有本征值 < math > lambda _ 1,那么 cdots,lambda _ n </math > ,结果只不过是具有相同本征向量的算子,但本征值 < math > log _ 2(lambda _ 1) ,点,log _ 2(lambda _ n) </math > 。那么香农熵就是:<br />
<br />
{{mvar|ρ<sub>A</sub>}} is sometimes called the reduced density matrix of {{mvar|ρ}} on subsystem {{mvar|A}}. Colloquially, we "trace out" system {{mvar|B}} to obtain the reduced density matrix on {{mvar|A}}.<br />
<br />
{mvar |ρ<sub>A</sub>}有时被称为子系统{mvar |ρ}上{mvar |ρ}的约化密度矩阵。通俗地说,我们“追踪”系统{mvar | B},得到{mvar | A}上的约化密度矩阵。<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
<br />
(rho) =-hbox { Tr } left (rho log 2{ rho } right) =-sum _ i lambda _ i log _ 2 lambda _ i </math > .<br />
<br />
For example, the reduced density matrix of {{mvar|A}} for the entangled state<br />
例如,纠缠态{mvar | A}的约化密度矩阵 <br />
<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
<br />
因为一个概率为0的事件不应该对熵有贡献,并且假设<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
<br />
<br />
<math> \lim_{p \to 0} p \log p = 0,</math><br />
<br />
[ math > lim _ { p to 0} p log p = 0,</math > <br />
<br />
discussed above is<br />
<br />
<br />
<br />
the convention 0}} is adopted. This extends to the infinite-dimensional case as well: if has spectral resolution<br />
<br />
约定0}被采用。这也延伸到无限维情况: 如果有光谱分辨率<br />
<br />
: <math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
<br />
<br />
<math> \rho = \int \lambda d P_{\lambda},</math><br />
<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of {{mvar|A}} for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
这表明,与预期一样,纠缠纯系综的约化密度矩阵是一个混合系综。同样不奇怪的是,上面讨论的纯积态{mvar | A}}的密度矩阵是 <br />
<br />
<br />
assume the same convention when calculating<br />
<br />
在计算时采用相同的约定<br />
<br />
: <math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
<br />
<br />
<math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
<br />
[数学] rho log 2 rho = int lambda log 2 lambda d { lambda }<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
一般来说,二部纯态ρ是纠缠的当且仅当它的约化态是混合态而不是纯态。 <br />
<br />
As in statistical mechanics, the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is (which can be shown to be the maximum entropy for mixed states).<br />
<br />
就像统计力学一样,系统的不确定性(微观状态的数量)越多,熵就越大。例如,任何纯态的熵都为零,这并不奇怪,因为处于纯态的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个的熵都是(混合态的最大熵)。<br />
<br />
=== Two applications that use them 两种使用它们的应用===<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional [[AKLT Model|AKLT spin chain]]:<ref name="Fan2004">{{cite journal | doi = 10.1103/PhysRevLett.93.227203 | title = Entanglement in a Valence-Bond Solid State | journal = Physical Review Letters | year = 2004 | first = H | last = Fan | page = 227203 |author2=Korepin V |author3=Roychowdhury V | volume = 93 | issue = 22 | pmid = 15601113 |arxiv=quant-ph/0406067 | bibcode=2004PhRvL..93v7203F| s2cid = 28587190 }}</ref> the ground state can be divided into a block and an environment. The reduced density matrix of the block is [[Proportionality (mathematics)|proportional]] to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist. If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
<br />
熵提供了一个可以用来量化纠缠的工具,尽管还存在其他的纠缠度量方法。如果整个系统是纯系统,则可以用一个子系统的熵来衡量其与其他子系统的纠缠程度。<br />
<br />
The reduced density matrix also was evaluated for [[Heisenberg model (quantum)|XY spin chains]], where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence<ref>{{cite journal| doi=10.1007/s11128-010-0197-7|arxiv=1002.2931|title=Spectrum of the density matrix of a large ''block of'' spins of the XY model in one dimension| year=2010|last1=Franchini|first1=F.|last2=Its|first2=A. R.|last3=Korepin|first3=V. E.|last4=Takhtajan|first4=L. A.|journal=Quantum Information Processing|volume=10|issue=3|pages=325–341|s2cid=6683370}}</ref> in this case.<br />
<br />
<br />
<br />
For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
<br />
对于两体纯态,减少态的冯纽曼熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的特定公理的态家族中唯一的函数。<br />
<br />
=== Entanglement as a resource 作为资源的纠缠===<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary [[quantum operation]]s can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called [[LOCC]] (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<ref name="horodecki2007" /><br />
在量子信息理论中,纠缠态被认为是一种“资源”,也就是说,生产成本高,可以实现有价值的转换。这种观点最明显的背景是“遥远的实验室”,即标记为“A”和“B”的两个量子系统,在每个量子系统上可以执行任意的[[量子操作]]s,但它们之间不以量子力学方式相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为[[LOCC]]的操作(局部操作和经典通信)。这些操作不允许在系统A和B之间产生纠缠态。但是如果A和B具有纠缠态的供应,那么这些操作与LOCC操作一起可以实现更大类别的变换。例如,a的一个量子位和B的一个量子位之间的相互作用可以通过首先将a的量子位传送到B,然后让它与B的量子位相互作用(现在是LOCC操作,因为两个量子位都在B的实验室里),然后将量子位传送回a来实现。在这个过程中,两个量子位的两个最大纠缠态被耗尽。因此,纠缠态是一种资源,能够在只有LOCC可用的情况下实现量子相互作用(或量子通道),但它们在过程中被消耗。在其他应用中,纠缠可以被视为一种资源,例如,私人通信或区分量子态。<br />
It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/n,...,1/n}. Therefore, a bipartite pure state is said to be a maximally entangled state if the reduced state of is the diagonal matrix<br />
<br />
一个经典的结果是,香农熵在均匀概率分布{1/n,... ,1/n }处达到最大值。因此,如果二分纯态的约化态是对角矩阵,则称二分纯态为最大纠缠态<br />
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<br />
<br />
=== Classification of entanglement 纠缠分类===<br />
<br />
<math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
<br />
< math > begin { bmatrix } frac {1}{ n } & & ddots & frac {1}{ n } end { bmatrix } . </math > <br />
<br />
Not all quantum states are equally valuable as a resource. To quantify this value, different [[Quantum entanglement#Entanglement measures|entanglement measures]] (see below) can be used, that assign a numerical value to each quantum state. However, it is often interesting to settle for a coarser way to compare quantum states. This gives rise to different classification schemes. Most entanglement classes are defined based on whether states can be converted to other states using LOCC or a subclass of these operations. The smaller the set of allowed operations, the finer the classification. Important examples are:<br />
并不是所有的量子态都具有同等的资源价值。为了量化这个值,可以使用不同的[[量子纠缠#纠缠度量|纠缠度量]](见下文),为每个量子态分配一个数值。然而,用一种更粗糙的方法来比较量子态是很有趣的。这就产生了不同的分类方案。大多数纠缠类的定义是基于是否可以使用LOCC或这些操作的子类将状态转换为其他状态。允许的操作集越小,分类就越精细。重要的例子有:<br />
* If two states can be transformed into each other by a local unitary operation, they are said to be in the same ''LU class''. This is the finest of the usually considered classes. Two states in the same LU class have the same value for entanglement measures and the same value as a resource in the distant-labs setting. There is an infinite number of different LU classes (even in the simplest case of two qubits in a pure state).<ref name="GRB1998">>{{cite journal |author1=Grassl, M. |author2=Rötteler, M. |author3=Beth, T. |title=Computing local invariants of quantum-bit systems |journal=Phys. Rev. A |volume=58 |issue=3 |pages=1833–1839 |year=1998 |doi=10.1103/PhysRevA.58.1833 |arxiv=quant-ph/9712040|bibcode=1998PhRvA..58.1833G |s2cid=15892529 }}</ref><ref name="Kraus2010">{{cite journal |author=B. Kraus |authorlink=Barbara Kraus|title=Local unitary equivalence of multipartite pure states |journal=Phys. Rev. Lett. |volume=104 |issue=2 |page=020504 |year=2010 |arxiv=0909.5152 |doi=10.1103/PhysRevLett.104.020504|pmid=20366579 |bibcode=2010PhRvL.104b0504K|s2cid=29984499}}</ref><br />
如果两个状态可以通过局部幺正运算相互转换,则称它们为同一“LU类”。这是通常认为最好的一类。同一LU类中的两个态具有相同的纠缠度量值,并且在远程实验室设置中具有相同的资源值。有无限多个不同的LU类(即使是在纯态中两个量子比特的最简单情况下)。<br />
For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
<br />
对于混合态,简化冯纽曼熵并不是唯一合理的纠缠度量。<br />
<br />
* If two states can be transformed into each other by local operations including measurements with probability larger than 0, they are said to be in the same 'SLOCC class' ("stochastic LOCC"). Qualitatively, two states <math>\rho_1</math> and <math>\rho_2</math> in the same SLOCC class are equally powerful (since I can transform one into the other and then do whatever it allows me to do), but since the transformations <math>\rho_1\to\rho_2</math> and <math>\rho_2\to\rho_1</math> may succeed with different probability, they are no longer equally valuable. E.g., for two pure qubits there are only two SLOCC classes: the entangled states (which contains both the (maximally entangled) Bell states and weakly entangled states like <math>|00\rangle+0.01|11\rangle</math>) and the separable ones (i.e., product states like <math>|00\rangle</math>).<ref>{{cite journal |author=M. A. Nielsen |title=Conditions for a Class of Entanglement Transformations |journal=Phys. Rev. Lett. |volume=83 |issue=2 |page=436 |year=1999 |doi=10.1103/PhysRevLett.83.436 |arxiv=quant-ph/9811053|bibcode=1999PhRvL..83..436N |s2cid=17928003 }}</ref><ref name="GoWa2010">{{cite journal |authors=Gour, G. & Wallach, N. R. |title=Classification of Multipartite Entanglement of All Finite Dimensionality |journal=Phys. Rev. Lett. |volume=111 |issue=6 |page=060502 |year=2013 |doi=10.1103/PhysRevLett.111.060502 |pmid=23971544 |arxiv=1304.7259|bibcode=2013PhRvL.111f0502G |s2cid=1570745 }}</ref><br />
如果两个状态可以通过局部操作(包括概率大于0的测量)相互转换,则它们被称为同一个“SLOCC类”(“随机LOCC”)。从质量上讲,同一SLOCC类中的两个状态<math>\rho\u 1</math>和<math>\rho\u 2</math>是同等强大的(因为我可以将一个状态转换为另一个状态,然后执行它允许我执行的任何操作),但是由于转换<math>\rho\u 1\到\rho\u 2</math>和<math>\rho\u 2\到\rho\u 1</math>可能以不同的概率成功,它们不再是同样有价值。E、 例如,对于两个纯量子位,只有两个SLOCC类:纠缠态(包含(最大纠缠)贝尔态和弱纠缠态,如<math>| 00\rangle+0.01 | 11\rangle</math>)和可分离态(即乘积态,如<math>| 00\rangle</math>)<br />
* Instead of considering transformations of single copies of a state (like <math>\rho_1\to\rho_2</math>) one can define classes based on the possibility of multi-copy transformations. E.g., there are examples when <math>\rho_1\to\rho_2</math> is impossible by LOCC, but <math>\rho_1\otimes\rho_1\to\rho_2</math> is possible. A very important (and very coarse) classification is based on the property whether it is possible to transform an arbitrarily large number of copies of a state <math>\rho</math> into at least one pure entangled state. States that have this property are called [[Entanglement distillation|distillable]]. These states are the most useful quantum states since, given enough of them, they can be transformed (with local operations) into any entangled state and hence allow for all possible uses. It came initially as a surprise that not all entangled states are distillable, those that are not are called '[[Bound entanglement|bound entangled]]'.<ref name="HHH97">{{cite journal |author1=Horodecki, M. |author2=Horodecki, P. |author3=Horodecki, R. |title=Mixed-state entanglement and distillation: Is there a ''bound'' entanglement in nature? |journal=Phys. Rev. Lett. |volume=80 |issue=1998 |pages=5239–5242 |year=1998 |arxiv=quant-ph/9801069|doi=10.1103/PhysRevLett.80.5239 |bibcode=1998PhRvL..80.5239H |s2cid=111379972 }}</ref><ref name="horodecki2007" /><br />
我们可以根据多副本转换的可能性来定义类,而不是考虑状态的单个副本的转换(如从<math>\rho\u1\到\rho\u2</math>)。E、 例如,有这样的例子:LOCC不可能实现<math>\rho\u 1\到\rho\u 2</math>,但有时可以实现<math>\rho\u 1\到\rho\u 2</math>。一个非常重要(而且非常粗糙)的分类是基于这样一个性质:是否有可能将一个态的任意多个拷贝<math>\rho</math>转换成至少一个纯纠缠态。具有这种性质的态称为[[纠缠蒸馏|可蒸馏]]。这些态是最有用的量子态,因为只要有足够的量子态,它们就可以(通过局部操作)转换成任何纠缠态,从而允许所有可能的用途。最初令人惊讶的是,并非所有的纠缠态都是可提取的,那些不可提取的被称为“[[束缚纠缠|束缚纠缠]]”。<br />
As an aside, the information-theoretic definition is closely related to entropy in the sense of statistical mechanics (comparing the two definitions in the present context, it is customary to set the Boltzmann constant 1}}). For example, by properties of the Borel functional calculus, we see that for any unitary operator ,<br />
<br />
顺便说一句,信息论的定义与统计力学意义上的熵密切相关(比较在当前语境下的两个定义,通常设置波兹曼常数1})。例如,通过 Borel 泛函微积分的性质,我们可以看到,对于任何幺正算符,<br />
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<br />
<br />
A different entanglement classification is based on what the quantum correlations present in a state allow A and B to do: one distinguishes three subsets of entangled states: (1) the ''[[Quantum nonlocality|non-local]] states'', which produce correlations that cannot be explained by a local hidden variable model and thus violate a Bell inequality, (2) the ''[[Quantum steering|steerable]] states'' that contain sufficient correlations for A to modify ("steer") by local measurements the conditional reduced state of B in such a way, that A can prove to B that the state they possess is indeed entangled, and finally (3) those entangled states that are neither non-local nor steerable. All three sets are non-empty.<ref name="WJD2007">{{cite journal |title=Steering, Entanglement, Nonlocality, and the Einstein-Podolsky-Rosen Paradox |authors=H. M. Wiseman, S. J. Jones, and A. C. Doherty |journal=Phys. Rev. Lett. |volume=98 |issue=14 |page=140402 |year=2007 |doi=10.1103/PhysRevLett.98.140402 |pmid=17501251 |arxiv=quant-ph/0612147|bibcode=2007PhRvL..98n0402W |s2cid=30078867 }}</ref><br />
<br />
<math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
s (rho) = s left (u rho u ^ * right) . </math > <br />
<br />
<br />
<br />
=== Entropy熵 ===<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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事实上,如果没有这个属性,冯纽曼熵就不会有明确的定义。<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
在本节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的量度。<br />
<br />
<br />
In particular, could be the time evolution operator of the system, i.e.,<br />
<br />
特别是,可以是系统的时间演化算子,即,<br />
<br />
==== Definition 定义====<br />
<br />
[[File:Von Neumann entropy for bipartite system plot.svg|right|thumb|200px|The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.]]<br />
<br />
<math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
<br />
[ math ] u (t) = exp left (frac {-i h t }{ hbar } right) ,[ math ]<br />
<br />
In classical [[information theory]] {{mvar|H}}, the [[Shannon entropy]], is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<ref name="SE">{{cite web |url=http://authors.library.caltech.edu/5516/1/CERpra97b.pdf#page=10 |title=Information-theoretic interpretation of quantum error-correcting codes |first1=Nicolas J. |last1=Cerf |first2=Richard |last2=Cleve }}</ref><br />
<br />
<br />
<br />
where is the Hamiltonian of the system. Here the entropy is unchanged.<br />
<br />
这个系统的哈密顿量在哪里。这里熵不变。<br />
<br />
: <math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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<br />
<br />
The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the arrow of time towards thermodynamic equilibrium is simply the growing spread of quantum entanglement.<br />
<br />
一个过程的可逆性与由此产生的熵变有关,也就是说,一个过程是可逆的,当且仅当它使系统的熵不变。因此,时间之箭向热力学平衡的前进只不过是量子纠缠的蔓延。<br />
<br />
Since a mixed state {{mvar|ρ}} is a probability distribution over an ensemble, this leads naturally to the definition of the [[von Neumann entropy]]:<br />
<br />
This provides a connection between quantum information theory and thermodynamics.<br />
<br />
这提供了量子信息理论和热力学之间的联系。<br />
<br />
<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
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Rényi entropy also can be used as a measure of entanglement.<br />
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熵也可以用来度量纠缠。<br />
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<br />
<br />
In general, one uses the [[Borel functional calculus]] to calculate a non-polynomial function such as {{math|log<sub>2</sub>(''ρ'')}}. If the nonnegative operator {{mvar|ρ}} acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, {{math|log<sub>2</sub>(''ρ'')}} turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
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<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, entanglement entropy is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<br />
<br />
量子纠缠度量了量子态(通常被视为双体)中纠缠的数量。如前所述,纠缠熵是纯态的标准量度(但不再是混合态的量度)。对于混合态,文献中有一些纠缠度量<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
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<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
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The Reeh-Schlieder theorem of quantum field theory is sometimes seen as an analogue of quantum entanglement.<br />
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量子场论的 Reeh-Schlieder 定理有时被看作是量子纠缠的类比。<br />
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<br />
<br />
:<math> \lim_{p \to 0} p \log p = 0,</math><br />
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<br />
the convention {{math|0 log(0) {{=}} 0}} is adopted. This extends to the infinite-dimensional case as well: if {{mvar|ρ}} has [[projection-valued measure|spectral resolution]]<br />
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Entanglement has many applications in quantum information theory. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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纠缠态在量子信息理论中有许多应用。在纠缠的帮助下,否则不可能完成的任务就可能实现。<br />
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<br />
<br />
: <math> \rho = \int \lambda d P_{\lambda},</math><br />
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Among the best-known applications of entanglement are superdense coding and quantum teleportation.<br />
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其中最著名的应用是超稠密编码和量子遥传纠缠。<br />
<br />
<br />
<br />
assume the same convention when calculating<br />
计算时假设相同的约定<br />
Most researchers believe that entanglement is necessary to realize quantum computing (although this is disputed by some).<br />
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大多数研究人员认为量子纠缠对于实现量子计算是必要的(尽管有些人对此有争议)。<br />
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<br />
<br />
: <math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
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Entanglement is used in some protocols of quantum cryptography. This is because the "shared noise" of entanglement makes for an excellent one-time pad. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.<br />
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纠缠被用于量子密码学的一些协议中。这是因为纠缠的“共享噪音”造就了绝佳的一次性衬垫。此外,由于测量纠缠对的任何一个成员都会破坏它们共享的纠缠,基于纠缠的量子密码学可以让发送方和接收方更容易地检测到拦截器的存在。<br />
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<br />
<br />
As in [[entropy|statistical mechanics]], the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is {{math|log(2)}} (which can be shown to be the maximum entropy for {{math|2 × 2}} mixed states).<br />
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在[[熵|统计力学]]中,系统应具有的不确定性(微观状态数)越多,熵就越大。例如,任何纯态的熵都是零,这并不奇怪,因为纯态下的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个子系统的熵是{math | log(2)}(这可以显示为{math | 2×2}混合态的最大熵)<br />
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In interferometry, entanglement is necessary for surpassing the standard quantum limit and achieving the Heisenberg limit.<br />
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在干涉术中,纠缠态对于超越标准量子极限和达到海森堡极限是必要的。<br />
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==== As a measure of entanglement作为纠缠的测量 ====<br />
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Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist.<ref name="arxiv.org">{{cite journal|author1=Plenio|title=An introduction to entanglement measures|year=2007|pages=1–51|volume=1|journal=Quant. Inf. Comp. |arxiv=quant-ph/0504163|bibcode=2005quant.ph..4163P|last2=Virmani}}</ref> If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
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There are several canonical entangled states that appear often in theory and experiments.<br />
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在理论和实验中经常会出现几种典型的纠缠态。<br />
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For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
对于二部纯态,约化态的von Neumann熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的某些公理的态族上的唯一函数。 <br />
For two qubits, the Bell states are<br />
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对于两个量子比特,贝尔态是<br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/''n'',...,1/''n''}. Therefore, a bipartite pure state {{math|''ρ'' ∈ ''H''<sub>A</sub> ⊗ ''H''<sub>B</sub>}} is said to be a '''maximally entangled state''' if the reduced state{{clarify|reason=To which system, A or B, or perhaps both?|date=May 2015}} of {{mvar|ρ}} is the diagonal matrix<br />
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<math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
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< math > | Phi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 0 rangle _ b | 1 rangle _ a o times | 1 rangle _ b) </math > <br />
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<math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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< math > | Psi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 1 rangle _ b pm | 1 rangle _ a o times | 0 rangle _ b) </math > .<br />
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: <math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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These four pure states are all maximally entangled (according to the entropy of entanglement) and form an orthonormal basis (linear algebra) of the Hilbert space of the two qubits. They play a fundamental role in Bell's theorem.<br />
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这四个纯态都是最大纠缠态(根据纠缠熵) ,并且形成了两个量子位的希尔伯特空间的标准正交基(线性代数)。它们在贝尔定理中起着基本的作用。<br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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For M>2 qubits, the GHZ state is<br />
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对于 m > 2量子位,GHZ 态是<br />
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As an aside, the information-theoretic definition is closely related to [[entropy (statistical views)|entropy]] in the sense of statistical mechanics{{Citation needed|date=January 2009}} (comparing the two definitions in the present context, it is customary to set the [[Boltzmann constant]] {{math|''k'' {{=}} 1}}). For example, by properties of the [[Borel functional calculus]], we see that for any [[unitary operator]] {{mvar|U}},<br />
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<math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
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< math > | mathrm { GHZ } rangle = frac { | 0 rangle ^ { otimes m } + | 1 rangle ^ { otimes m }{ sqrt {2} ,</math > <br />
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: <math>S(\rho) = S \left (U \rho U^* \right).</math><br />
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which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to qudits, i.e., systems of d rather than 2 dimensions.<br />
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它缩小到贝尔状态。传统的 GHZ 状态定义为 < math > m = 3 </math > 。GHZ 状态偶尔会扩展到 qudit,即 d 而不是2维系统。<br />
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Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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Also for M>2 qubits, there are spin squeezed states. Spin squeezed states are a class of squeezed coherent states satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled. Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<br />
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对于 m > 2量子位,也存在自旋压缩态。自旋压缩态是一类对自旋测量不确定度满足一定限制的压缩相干态,它必然是纠缠态。自旋压缩态是利用量子纠缠增强精密测量的理想候选态。<br />
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In particular, {{mvar|U}} could be the time evolution operator of the system, i.e.,<br />
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For two bosonic modes, a NOON state is<br />
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对于两个玻色模态,NOON 状态是<br />
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: <math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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<math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
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[数学] | psi _ text { NOON } rangle = frac { | n rangle _ a | 0 rangle _ b + | {0} rangle _ a | { n } rangle _ b }{ sqrt {2} ,,</math > <br />
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where {{mvar|H}} is the [[Hamiltonian (quantum mechanics)|Hamiltonian]] of the system. Here the entropy is unchanged.<br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the N photons are in one mode" and "the N photons are in the other mode".<br />
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这就像贝尔态 < math > | Psi ^ + rangle </math > 除了基函数0和1已经被“ n 个光子处于一种模式”和“ n 个光子处于另一种模式”所取代。<br />
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The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the [[arrow of time]] towards [[thermodynamic equilibrium]] is simply the growing spread of quantum entanglement.<ref>{{cite news |url=https://www.wired.com/2014/04/quantum-theory-flow-time/ |title=New Quantum Theory Could Explain the Flow of Time |last1=Wolchover |first1=Natalie |date=25 April 2014 |website=www.wired.com |publisher=Quanta Magazine |accessdate=27 April 2014}}</ref><br />
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This provides a connection between [[quantum information theory]] and [[thermodynamics]].<br />
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Finally, there also exist twin Fock states for bosonic modes, which can be created by feeding a Fock state into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<br />
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最后,还存在玻色子模式的双 Fock 态,它可以通过将 Fock 态输入到两个导致分束器的臂来产生。它们是 NOON 态的倍数之和,可以用来实现海森堡极限。<br />
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[[Rényi entropy]] also can be used as a measure of entanglement.<br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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对于适当选择的纠缠度量,Bell、 GHZ 和 NOON 态是最大纠缠态,而自旋压缩态和双 Fock 态只是部分纠缠。部分纠缠态通常更容易在实验上准备。<br />
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=== Entanglement measures ===<br />
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Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, [[entropy of entanglement|entanglement entropy]] is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<ref name="arxiv.org" /> and no single one is standard.<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is spontaneous parametric down-conversion to generate a pair of photons entangled in polarisation. Other methods include the use of a fiber coupler to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a quantum dot, the use of the Hong–Ou–Mandel effect, etc., In the earliest tests of Bell's theorem, the entangled particles were generated using atomic cascades.<br />
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纠缠通常是由亚原子粒子间的直接相互作用产生的。这些相互作用可以有多种形式。最常用的方法之一是用自发参量下转换产生一对纠缠在偏振中的光子。其他方法包括使用光纤耦合器来限制和混合光子,量子点中双激子衰变级联发射的光子,Hong-Ou-Mandel 效应的使用等等。在贝尔定理最早的测试中,纠缠粒子是利用原子级联产生的。<br />
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* Entanglement cost<br />
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* [[entanglement distillation|Distillable entanglement]]<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of entanglement swapping. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<br />
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通过使用纠缠交换,也有可能在不直接相互作用的量子系统之间创造纠缠。如果它们的波函数在空间上仅仅重叠,至少是部分重叠,那么它们也可以相互纠缠全同粒子。<br />
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* Entanglement of formation<br />
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* [[quantum relative entropy|Relative entropy of entanglement]]<br />
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* [[Squashed entanglement]]<br />
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* [[Logarithmic negativity]]<br />
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A density matrix ρ is called separable if it can be written as a convex sum of product states, namely<br />
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密度矩阵 ρ 称为可分的,如果它可以写成乘积态的凸和,即<br />
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Most (but not all) of these entanglement measures reduce for pure states to entanglement entropy, and are difficult ([[NP-hard]]) to compute.<ref>{{cite journal|last1=Huang|first1=Yichen|title=Computing quantum discord is NP-complete|journal=New Journal of Physics|date=21 March 2014|volume=16|issue=3|pages=033027|doi=10.1088/1367-2630/16/3/033027|bibcode=2014NJPh...16c3027H|arxiv = 1305.5941 |s2cid=118556793}}</ref><br />
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<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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显示方式{ rho = sum _ j p _ j rho _ j ^ {(a)}次 rho _ j ^ {(b)}} </math > <br />
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=== Quantum field theory ===<br />
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The [[Reeh-Schlieder theorem]] of [[quantum field theory]] is sometimes seen as an analogue of quantum entanglement.<br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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概率为1 ge p _ j ge 0 </math > 。根据定义,如果一个态不可分离,它就是纠缠态。<br />
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== Applications ==<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple Peres–Horodecki criterion provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes NP-hard when generalized. Other separability criteria include (but not limited to) the range criterion, reduction criterion, and those based on uncertainty relations. See Ref. for a review of separability criteria in discrete variable systems.<br />
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对于2量子比特和2 × 2量子比特-量子特里特系统(分别为2 × 2和2 × 3) ,简单的 Peres-horowitz 准则为分离提供了一个必要和充分的判据,从而无意识地提供了检测纠缠的判据。然而,对于一般情形,该判据仅仅是可分性的必要条件,因为问题一经推广就变成了 np 难问题。其他可分性标准包括(但不限于)范围标准、归约标准和基于不确定关系的标准。参见参考文献。回顾了离散变量系统的可分性准则。<br />
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Entanglement has many applications in [[quantum information theory]]. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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A numerical approach to the problem is suggested by Jon Magne Leinaas, Jan Myrheim and Eirik Ovrum in their paper "Geometrical aspects of entanglement". Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in Peres-Horodecki criterion testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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Jon Magne Leinaas,Jan Myrheim 和 Eirik Ovrum 在他们的论文“纠缠的几何方面”中提出了一个数值方法来解决这个问题。莱纳斯等。提供一个数值方法,迭代精炼一个估计的可分离状态朝向要测试的目标状态,并检查目标状态是否确实能够到达。该算法的一个实现(包括内置的 peres-horowitz 标准测试)是[ StateSeparator http://phweb.technion.ac.il/~StateSeparator/] web-app。<br />
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Among the best-known applications of entanglement are [[superdense coding]] and [[quantum teleportation]].<ref>{{cite journal |last1=Bouwmeester |first1=Dik |last2=Pan |first2=Jian-Wei|last3=Mattle |first3=Klaus|last4=Eibl |first4=Manfred |last5=Weinfurter |first5=Harald|last6=Zeilinger |first6=Anton|year=1997 |title=Experimental Quantum Teleportation |journal=Nature |volume=390 |issue=6660 |pages=575–579 |name-list-style=amp |url=http://qudev.ethz.ch/content/courses/QSIT06/pdfs/Bouwmeester97.pdf |doi=10.1038/37539|bibcode = 1997Natur.390..575B |arxiv=1901.11004 |s2cid=4422887 }}</ref><br />
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In continuous variable systems, the Peres-Horodecki criterion also applies. Specifically, Simon formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref. for a seemingly different but essentially equivalent approach). It was later found that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators or by using entropic measures.<br />
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在连续变量系统中,Peres-Horodecki 准则也适用。具体地说,Simon 根据正则算符的二阶矩,制定了 Peres-Horodecki 准则的一个特定版本,并表明它对于 < math > 1 oplus1 </math >-mode Gaussian 状态是必要的和充分的。看似不同,但本质上等价的方法)。后来发现,Simon 的条件对于 < math > 1 oplus n </math >-mode Gaussian 状态也是必要和充分的,但是对于 < math > 2 oplus2 </math >-mode Gaussian 状态不再是充分的。Simon 条件可以通过考虑正则算子的高阶矩或者用熵测度来推广。<br />
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Most researchers believe that entanglement is necessary to realize [[quantum computer|quantum computing]] (although this is disputed by some).<ref name="jozsa02">{{cite journal|author1=Richard Jozsa|author2=Noah Linden|doi=10.1098/rspa.2002.1097|title=On the role of entanglement in quantum computational speed-up|year=2002|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=459|issue=2036|pages=2011–2032|arxiv=quant-ph/0201143|bibcode = 2003RSPSA.459.2011J |citeseerx=10.1.1.251.7637|s2cid=15470259}}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite. The $100m Quantum Experiments at Space Scale (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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2016年,中国发射了世界上第一颗量子通信卫星。耗资1亿美元的空间量子实验任务于2016年8月16日当地时间01:40从中国北方的酒泉卫星发射中心空间站发射升空。<br />
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Entanglement is used in some protocols of [[quantum cryptography]].<ref name="ekert91">{{cite journal |doi=10.1103/PhysRevLett.67.661 |title=Quantum cryptography based on Bell's theorem |year=1991 |last1=Ekert |first1=Artur K. |journal=Physical Review Letters |volume=67 |issue=6 |pages=661–663 |pmid=10044956|bibcode = 1991PhRvL..67..661E |s2cid=27683254 |url=http://pdfs.semanticscholar.org/f8dc/c3047eef8da135bca13b926b1e6cf50e7f3a.pdf }}</ref><ref name="horodecki10">{{cite arXiv |eprint=1006.0468|last1=Yin|first1=Juan|title=Contextuality offers device-independent security|last2=Cao|first2=Yuan|last3=Yong|first3=Hai-Lin|last4=Ren|first4=Ji-Gang|last5=Liang|first5=Hao|last6=Liao|first6=Sheng-Kai|last7=Zhou|first7=Fei|last8=Liu|first8=Chang|last9=Wu|first9=Yu-Ping|last10=Pan|first10=Ge-Sheng|last11=Zhang|first11=Qiang|last12=Peng|first12=Cheng-Zhi|last13=Pan|first13=Jian-Wei|class=quant-ph|year=2010}}</ref> This is because the "shared noise" of entanglement makes for an excellent [[one-time pad]]. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.{{citation needed|date=January 2018}}<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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在接下来的两年里,这艘以中国古代哲学家墨子命名的飞船将展示量子化的可行性<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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地球和太空之间的通信,并在前所未有的距离上测试量子纠缠。<br />
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In [[interferometry]], entanglement is necessary for surpassing the [[standard quantum limit]] and achieving the [[Heisenberg limit]].<ref>{{cite journal |last1=Pezze |first1=Luca |last2=Smerzi |first2=Augusto|year=2009 |title=Entanglement, Nonlinear Dynamics, and the Heisenberg Limit |journal=Phys. Rev. Lett. |volume=102 |issue=10 |pages=100401 |name-list-style=amp |doi=10.1103/PhysRevLett.102.100401 |pmid=19392092 |bibcode=2009PhRvL.102j0401P|arxiv = 0711.4840 |s2cid=13095638 }}</ref><br />
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In the June 16, 2017, issue of Science, Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<br />
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在2017年6月16日的《科学》杂志上。在严格的爱因斯坦定域条件下,从墨丘利卫星到 Lijian、云南和 Delingha、 Quinhai 的基地的 CHSH 估值为2.37 ± 0.09,证明了双光子对的存在和对 Bell 不等式的违反,从而提高了数量级通过光纤实验的传输效率。<br />
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=== Entangled states ===<br />
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There are several canonical entangled states that appear often in theory and experiments.<br />
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For two [[qubits]], the [[Bell state]]s are<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be calculated only by consideration of electron entanglement.<br />
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多电子原子的电子壳层总是由纠缠电子组成。只有考虑到电子纠缠,才能计算出正确的电离能。<br />
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: <math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
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: <math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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It has been suggested that in the process of photosynthesis, entanglement is involved in the transfer of energy between light-harvesting complexes and photosynthetic reaction centers where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using femtosecond spectroscopy, the coherence of entanglement in the Fenna-Matthews-Olson complex was measured over hundreds of femtoseconds (a relatively long time in this regard) providing support to this theory.<br />
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研究表明,在光合作用过程中,纠缠参与了捕光复合物与光合反应中心之间的能量传递,而光(能)是以化学能的形式获得的。没有这样一个过程,光转化为化学能的有效性就无从解释。利用飞秒光谱技术,我们测量了 Fenna-Matthews-Olson 复合体中纠缠态的相干性,时间长达数百飞秒,为这一理论提供了支持。<br />
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These four pure states are all maximally entangled (according to the [[entropy of entanglement]]) and form an [[orthonormal]] [[basis (linear algebra)]] of the Hilbert space of the two qubits. They play a fundamental role in [[Bell's theorem]].<br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<br />
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然而,关键的后续研究对这些结果的解释提出了质疑,并将报告的电子量子相干特征赋予了发色团中的核动力学。<br />
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For M>2 qubits, the [[Greenberger–Horne–Zeilinger state|GHZ state]] is<br />
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In 2020 researchers reported the quantum entanglement between the motion of a millimetre-sized mechanical oscillator and a disparate distant spin system of a cloud of atoms.<br />
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2020年,研究人员报告了一个毫米大小的机械振荡器的运动和一个原子云的不同距离的自旋系统之间的量子纠缠。<br />
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: <math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
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which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to [[qudit]]s, i.e., systems of ''d'' rather than 2 dimensions.<br />
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In October 2018, physicists reported producing quantum entanglement using living organisms, particularly between photosynthetic molecules within living bacteria and quantized light.<br />
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2018年10月,物理学家报告说,他们利用活体生物制造量子纠缠,特别是利用活体细菌中的光合分子和量子化的光。<br />
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Also for M>2 qubits, there are [[Spin squeezing|spin squeezed states]].<ref>[http://qwiki.stanford.edu/index.php/Spin_Squeezed_State Database error – Qwiki] {{webarchive|url=https://web.archive.org/web/20120821011018/http://qwiki.stanford.edu/index.php/Spin_Squeezed_State |date=21 August 2012 }}</ref> Spin squeezed states are a class of [[squeezed coherent states]] satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled.<ref>{{cite journal | last1 = Kitagawa | first1 = Masahiro | last2 = Ueda | first2 = Masahito | year = 1993 | title = Squeezed Spin States | journal = Phys. Rev. A | volume = 47 | issue = 6| pages = 5138–5143 | doi=10.1103/physreva.47.5138| pmid = 9909547 |bibcode = 1993PhRvA..47.5138K }}</ref> Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<ref>{{cite journal | last1 = Wineland | first1 = D. J. | last2 = Bollinger | first2 = J. J. | last3 = Itano | first3 = W. M. | last4 = Moore | first4 = F. L. | last5 = Heinzen | first5 = D. J. | year = 1992| title = Spin squeezing and reduced quantum noise in spectroscopy | url = | journal = Phys. Rev. A | volume = 46| issue = 11| pages = R6797–R6800| doi = 10.1103/PhysRevA.46.R6797 | pmid = 9908086 |bibcode = 1992PhRvA..46.6797W }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<br />
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生物体(绿色硫细菌)已被研究作为介质,在非相互作用的光模式之间创造量子纠缠,表明光和细菌模式之间的高度纠缠,甚至在某种程度上纠缠在细菌内部。<br />
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For two [[boson]]ic modes, a [[NOON state]] is<br />
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: <math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the ''N'' photons are in one mode" and "the ''N'' photons are in the other mode".<br />
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Finally, there also exist [[twin Fock states]] for bosonic modes, which can be created by feeding a [[Fock state]] into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.71.1355|pmid = 10055519|title = Interferometric detection of optical phase shifts at the Heisenberg limit|journal = Physical Review Letters|volume = 71|issue = 9|pages = 1355–1358|year = 1993|last1 = Holland|first1 = M. J|last2 = Burnett|first2 = K|bibcode = 1993PhRvL..71.1355H}}</ref><br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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=== Methods of creating entanglement ===<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is [[spontaneous parametric down-conversion]] to generate a pair of photons entangled in polarisation.<ref name="horodecki2007">{{cite journal |author=Horodecki R, Horodecki P, Horodecki M, Horodecki K |title=Quantum entanglement |journal=Rev. Mod. Phys. |arxiv=quant-ph/0702225 |doi =10.1103/RevModPhys.81.865 |year=2009|pages=865–942 |bibcode=2009RvMP...81..865H |volume=81 |issue=2|last2=Horodecki |last3=Horodecki |last4=Horodecki |s2cid=59577352 }}</ref> Other methods include the use of a [[fiber coupler]] to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a [[quantum dot]],<ref>{{Cite journal|last=Akopian|first=N.|date=2006|title=Entangled Photon Pairs from Semiconductor Quantum Dots|journal=Phys. Rev. Lett.|volume=96|issue=2|pages=130501|arxiv=quant-ph/0509060|bibcode=2006PhRvL..96b0501D|doi=10.1103/PhysRevLett.96.020501|pmid=16486553|s2cid=22040546}}</ref> the use of the [[Hong–Ou–Mandel effect]], etc., In the earliest tests of Bell's theorem, the entangled particles were generated using [[atomic cascade]]s.<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of [[Quantum teleportation#Entanglement swapping|entanglement swapping]]. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<ref>Rosario Lo Franco and Giuseppe Compagno, "Indistinguishability of Elementary Systems as a Resource for Quantum Information Processing", Phys. Rev. Lett. 120, 240403, 14 June 2018.</ref><br />
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=== Testing a system for entanglement ===<br />
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A density matrix ρ is called [[Separable state|separable]] if it can be written as a convex sum of product states, namely<br />
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<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple [[Peres–Horodecki criterion]] provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes [[NP-hard]] when generalized.<ref name="NP-hard1">Gurvits, L., Classical deterministic complexity of Edmonds' problem and quantum entanglement, in Proceedings of the 35th ACM Symposium on Theory of Computing, ACM Press, New York, 2003.</ref><ref name="NP-hard2">Sevag Gharibian, Strong NP-Hardness of the [[Quantum Separability Problem]], [[Quantum Information]] and what's known as [[Quantum Computing]], Vol. 10, No. 3&4, pp. 343–360, 2010. {{arXiv|0810.4507}}.</ref> Other separability criteria include (but not limited to) the [[range criterion]], [[reduction criterion]], and those based on uncertainty relations.<ref>{{cite journal |last1=Hofmann |first1=Holger F. |last2=Takeuchi |first2=Shigeki |title=Violation of local uncertainty relations as a signature of entanglement |journal=Physical Review A |date=22 September 2003 |volume=68 |issue=3 |page=032103 |doi=10.1103/PhysRevA.68.032103|arxiv=quant-ph/0212090 |bibcode=2003PhRvA..68c2103H |s2cid=54893300 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |title=Characterizing Entanglement via Uncertainty Relations |journal=Physical Review Letters |date=18 March 2004 |volume=92 |issue=11 |page=117903 |doi=10.1103/PhysRevLett.92.117903|pmid=15089173 |arxiv=quant-ph/0306194 |bibcode=2004PhRvL..92k7903G |s2cid=5696147 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |last2=Lewenstein |first2=Maciej |title=Entropic uncertainty relations and entanglement |journal=Physical Review A |date=24 August 2004 |volume=70 |issue=2 |page=022316 |doi=10.1103/PhysRevA.70.022316|bibcode=2004PhRvA..70b2316G |arxiv=quant-ph/0403219 |s2cid=118952931 }}</ref><ref>{{cite journal |last1=Huang |first1=Yichen |title=Entanglement criteria via concave-function uncertainty relations |journal=Physical Review A |date=29 July 2010 |volume=82 |issue=1 |page=012335 |doi=10.1103/PhysRevA.82.012335|bibcode=2010PhRvA..82a2335H }}</ref> See Ref.<ref>{{cite journal|last1=Gühne|first1=Otfried|last2=Tóth|first2=Géza|title=Entanglement detection|journal=Physics Reports|volume=474|issue=1–6|pages=1–75|doi=10.1016/j.physrep.2009.02.004|arxiv = 0811.2803 |bibcode = 2009PhR...474....1G |year=2009|s2cid=119288569}}</ref> for a review of separability criteria in discrete variable systems.<br />
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A numerical approach to the problem is suggested by [[Jon Magne Leinaas]], [[Jan Myrheim]] and [[Eirik Ovrum]] in their paper "Geometrical aspects of entanglement".<ref name="geom approach">{{cite journal | last1 = Leinaas| first1 = Jon Magne| last2 = Myrheim| first2 = Jan| last3 = Ovrum| first3 = Eirik| year = 2006 | title = Geometrical aspects of entanglement | url = | journal = Physical Review A | volume = 74 | issue = | page = 012313 | doi = 10.1103/PhysRevA.74.012313| arxiv = quant-ph/0605079| s2cid = 119443360}}</ref> Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in [[Peres-Horodecki criterion]] testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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In continuous variable systems, the [[Peres-Horodecki criterion]] also applies. Specifically, Simon <ref>{{cite journal|last1=Simon|first1=R.|title=Peres-Horodecki Separability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2726–2729|doi=10.1103/PhysRevLett.84.2726|arxiv = quant-ph/9909044 |bibcode = 2000PhRvL..84.2726S|pmid=11017310|year=2000|s2cid=11664720}}</ref> formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref.<ref>{{cite journal|last1=Duan|first1=Lu-Ming|last2=Giedke|first2=G.|last3=Cirac|first3=J. I.|last4=Zoller|first4=P.|title=Inseparability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2722–2725|doi=10.1103/PhysRevLett.84.2722|pmid=11017309|arxiv = quant-ph/9908056 |bibcode = 2000PhRvL..84.2722D |year=2000|s2cid=9948874}}</ref> for a seemingly different but essentially equivalent approach). It was later found <ref>{{cite journal|last1=Werner|first1=R. F.|last2=Wolf|first2=M. M.|title=Bound Entangled Gaussian States|journal=Physical Review Letters|volume=86|issue=16|pages=3658–3661|doi=10.1103/PhysRevLett.86.3658|pmid=11328047|arxiv = quant-ph/0009118 |bibcode = 2001PhRvL..86.3658W |year=2001|s2cid=20897950}}</ref> that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators <ref>{{cite journal|last1=Shchukin|first1=E.|last2=Vogel|first2=W.|title=Inseparability Criteria for Continuous Bipartite Quantum States|journal=Physical Review Letters|volume=95|issue=23|pages=230502|doi=10.1103/PhysRevLett.95.230502|pmid=16384285|arxiv = quant-ph/0508132 |bibcode = 2005PhRvL..95w0502S |year=2005|s2cid=28595936}}</ref><ref>{{cite journal|last1=Hillery|first1=Mark|last2=Zubairy|first2=M.Suhail|title=Entanglement Conditions for Two-Mode States|journal=Physical Review Letters|volume=96|issue=5|doi=10.1103/PhysRevLett.96.050503|arxiv = quant-ph/0507168 |bibcode = 2006PhRvL..96e0503H|pmid=16486912|page=050503|year=2006|s2cid=43756465}}</ref> or by using entropic measures.<ref>{{cite journal|last1=Walborn|first1=S.|last2=Taketani|first2=B.|last3=Salles|first3=A.|last4=Toscano|first4=F.|last5=de Matos Filho|first5=R.|title=Entropic Entanglement Criteria for Continuous Variables|journal=Physical Review Letters|volume=103|issue=16|doi=10.1103/PhysRevLett.103.160505|arxiv = 0909.0147 |bibcode = 2009PhRvL.103p0505W|pmid=19905682|page=160505|year=2009|s2cid=10523704}}</ref><ref>{{cite journal |last1=Yichen Huang |title=Entanglement Detection: Complexity and Shannon Entropic Criteria |journal=IEEE Transactions on Information Theory |date=October 2013 |volume=59 |issue=10 |pages=6774–6778 |doi=10.1109/TIT.2013.2257936|s2cid=7149863 }}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite.<ref>http://physicsworld.com/cws/article/news/2016/aug/16/china-launches-world-s-first-quantum-science-satellite</ref> The $100m [[Quantum Experiments at Space Scale]] (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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In the June 16, 2017, issue of ''Science'', Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<ref>{{cite journal | doi = 10.1126/science.aan3211 | volume=356 | title=Satellite-based entanglement distribution over 1200 kilometers | year=2017 | journal=Science | pages=1140–1144 | last1 = Yin | first1 = Juan | last2 = Cao | first2 = Yuan | last3 = Li | first3 = Yu-Huai | last4 = Liao | first4 = Sheng-Kai | last5 = Zhang | first5 = Liang | last6 = Ren | first6 = Ji-Gang | last7 = Cai | first7 = Wen-Qi | last8 = Liu | first8 = Wei-Yue | last9 = Li | first9 = Bo | last10 = Dai | first10 = Hui | last11 = Li | first11 = Guang-Bing | last12 = Lu | first12 = Qi-Ming | last13 = Gong | first13 = Yun-Hong | last14 = Xu | first14 = Yu | last15 = Li | first15 = Shuang-Lin | last16 = Li | first16 = Feng-Zhi | last17 = Yin | first17 = Ya-Yun | last18 = Jiang | first18 = Zi-Qing | last19 = Li | first19 = Ming | last20 = Jia | first20 = Jian-Jun | last21 = Ren | first21 = Ge | last22 = He | first22 = Dong | last23 = Zhou | first23 = Yi-Lin | last24 = Zhang | first24 = Xiao-Xiang | last25 = Wang | first25 = Na | last26 = Chang | first26 = Xiang | last27 = Zhu | first27 = Zhen-Cai | last28 = Liu | first28 = Nai-Le | last29 = Chen | first29 = Yu-Ao | last30 = Lu | first30 = Chao-Yang | last31 = Shu | first31 = Rong | last32 = Peng | first32 = Cheng-Zhi | last33 = Wang | first33 = Jian-Yu | last34 = Pan | first34 = Jian-Wei | issue=6343 | pmid = 28619937| doi-access = free }}</ref><ref>{{cite web | url=http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance | title=China's quantum satellite achieves 'spooky action' at record distance| date=2017-06-14}}</ref><br />
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== Naturally entangled systems ==<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be [[Configuration interaction|calculated]] only by consideration of electron entanglement.<ref>Frank Jensen: ''Introduction to Computational Chemistry.'' Wiley, 2007, {{ISBN|978-0-470-01187-4}}.</ref><br />
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== Photosynthesis ==<br />
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It has been suggested that in the process of [[photosynthesis]], entanglement is involved in the transfer of energy between [[light-harvesting complex]]es and [[photosynthetic reaction center]]s where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using [[femtosecond spectroscopy]], the coherence of entanglement in the [[Fenna-Matthews-Olson complex]] was measured over hundreds of [[femtosecond]]s (a relatively long time in this regard) providing support to this theory.<ref>Berkeley Lab Press Release: ''[http://newscenter.lbl.gov/feature-stories/2010/05/10/untangling-quantum-entanglement/ Untangling the Quantum Entanglement Behind Photosynthesis: Berkeley scientists shine new light on green plant secrets.]''</ref><ref>Mohan Sarovar, Akihito Ishizaki, Graham R. Fleming, K. Birgitta Whaley: ''Quantum entanglement in photosynthetic light harvesting complexes.'' {{arxiv|0905.3787}}</ref><br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<ref>{{cite journal | author = R. Tempelaar | author2 = T. L. C. Jansen | author3 = J. Knoester | title = Vibrational Beatings Conceal Evidence of Electronic Coherence in the FMO Light-Harvesting Complex | journal = J. Phys. Chem. B | volume = 118 | issue = 45 | pages = 12865–12872 | date = 2014 | doi=10.1021/jp510074q| pmid = 25321492 }}</ref><ref>{{cite journal | author = N. Christenson | author2 = H. F. Kauffmann | author3 = T. Pullerits | author4 = T. Mancal | title = Origin of Long-Lived Coherences in Light-Harvesting Complexes| journal = J. Phys. Chem. B | volume = 116 | issue = 25 | pages = 7449–7454 | date = 2012 | doi = 10.1021/jp304649c | pmid = 22642682 | pmc = 3789255 | bibcode = 2012arXiv1201.6325C | arxiv = 1201.6325 }}</ref><ref>{{cite journal | author = A. Kolli | author2 = E. J. O’Reilly | author3= G. D. Scholes | author4= A. Olaya-Castro | title = The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae| journal = J. Chem. Phys. | volume = 137 | issue = 17 | pages = 174109 | date = 2012 | doi=10.1063/1.4764100| pmid = 23145719 | bibcode = 2012JChPh.137q4109K | arxiv = 1203.5056 | s2cid = 20156821 }}</ref><ref>{{cite journal | author = V. Butkus | author2 = D. Zigmantas | author3= L. Valkunas | author4= D. Abramavicius | title = Vibrational vs. electronic coherences in 2D spectrum of molecular systems| journal = Chem. Phys. Lett. | volume = 545 | issue = 30 | pages = 40–43 | date = 2012 | doi=10.1016/j.cplett.2012.07.014| arxiv = 1201.2753 | bibcode = 2012CPL...545...40B | s2cid = 96663719 }}</ref><ref>{{cite journal | author = V. Tiwari | author2 = W. K. Peters | author3= D. M. Jonas | title = Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework | journal = Proc. Natl. Acad. Sci. USA | volume = 110 | issue = 4 | pages = 1203–1208 | date = 2013 | doi=10.1073/pnas.1211157110| pmid = 23267114 | pmc = 3557059 }}</ref><ref>{{cite journal | author = E. Thyrhaug | author2 = K. Zidek | author3 = J. Dostal | author4 = D. Bina | author5 = D. Zigmantas | title = Exciton Structure and Energy Transfer in the Fenna−Matthews− Olson Complex| journal = J. Phys. Chem. Lett. | volume = 7 | issue = 9 | pages = 1653–1660 | date = 2016 | doi=10.1021/acs.jpclett.6b00534| pmid = 27082631 }}</ref><ref>{{cite journal | author = Y. Fujihashi | author2 = G. R. Fleming | author3= A. Ishizaki | title = Impact of environmentally induced fluctuations on quantum mechanically mixed electronic and vibrational pigment states in photosynthetic energy transfer and 2D electronic spectra| journal = J. Chem. Phys. | volume = 142 | issue = 21 | pages = 212403 | date = 2015 | doi=10.1063/1.4914302| pmid = 26049423 | arxiv = 1505.05281 | bibcode = 2015JChPh.142u2403F | s2cid = 1082742 }}</ref><br />
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== Entanglement of macroscopic objects ==<br />
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In 2020 researchers reported the quantum entanglement between the [[Vibrations of a circular membrane|motion of a millimetre-sized mechanical oscillator]] and a disparate distant [[Spin (physics)|spin]] system of a cloud of atoms.<ref>{{cite news |title=Quantum entanglement realized between distant large objects |url=https://phys.org/news/2020-09-quantum-entanglement-distant-large.html |accessdate=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Thomas |first1=Rodrigo A. |last2=Parniak |first2=Michał |last3=Østfeldt |first3=Christoffer |last4=Møller |first4=Christoffer B. |last5=Bærentsen |first5=Christian |last6=Tsaturyan |first6=Yeghishe |last7=Schliesser |first7=Albert |last8=Appel |first8=Jürgen |last9=Zeuthen |first9=Emil |last10=Polzik |first10=Eugene S. |title=Entanglement between distant macroscopic mechanical and spin systems |journal=Nature Physics |date=21 September 2020 |pages=1–6 |doi=10.1038/s41567-020-1031-5 |url=https://www.nature.com/articles/s41567-020-1031-5 |accessdate=9 October 2020 |language=en |issn=1745-2481}}</ref><br />
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=== Entanglement of elements of living systems ===<br />
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In October 2018, physicists reported producing quantum entanglement using [[living organism]]s, particularly between photosynthetic molecules within living [[bacteria]] and [[Photon|quantized light]].<ref name="JPC-20181010">{{cite journal |last1=Marletto |first1=C. |last2=Coles |first2=D.M. |last3=Farrow |first3=T. |last4=Vedral |first4=V. |title=Entanglement between living bacteria and quantized light witnessed by Rabi splitting |date=10 October 2018 |journal=Journal of Physics: Communications |volume=2 |pages=101001 |number=10 |doi=10.1088/2399-6528/aae224 |bibcode=2018JPhCo...2j1001M |arxiv=1702.08075 |s2cid=119236759 }} [[File:CC-BY icon.svg|50px]] Text and images are available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref><ref name="SA-20181029">{{cite web |last=O'Callaghan |first=Jonathan |title="Schrödinger's Bacterium" Could Be a Quantum Biology Milestone – A recent experiment may have placed living organisms in a state of quantum entanglement |url=https://www.scientificamerican.com/article/schroedingers-bacterium-could-be-a-quantum-biology-milestone/ |date=29 October 2018 |work=[[Scientific American]] |accessdate=29 October 2018 }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<ref>{{cite journal | last1 = Krisnanda | first1 = T. | last2 = Marletto | first2 = C. | last3 = Vedral | first3 = V. | last4 = Paternostro | first4 = M. | last5 = Paterek | first5 = T. | year = 2018 | title = Probing quantum features of photosynthetic organisms | url = https://www.nature.com/articles/s41534-018-0110-2 | journal = NPJ Quantum Information | volume = 4 | issue = | page = 60 | doi = 10.1038/s41534-018-0110-2 | doi-access = free }}</ref><br />
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== See also ==<br />
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{{Portal|Physics}}<br />
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{{cols|colwidth=21em}}<br />
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* [[Quantum gate#Controlled gates|CNOT gate]]<br />
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* [[Bound entanglement]]<br />
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* [[Concurrence (quantum computing)]]<br />
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* [[Einstein's thought experiments]]<br />
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* [[Entanglement distillation]]<br />
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* [[Entanglement witness]]<br />
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* [[Faster-than-light communication]]<br />
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* [[Ghirardi–Rimini–Weber theory]]<br />
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* [[Multipartite entanglement]]<br />
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* [[Normally distributed and uncorrelated does not imply independent]]<br />
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* [[Observer effect (physics)]]<br />
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* [[Quantum coherence]]<br />
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* [[Quantum discord]]<br />
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* [[Quantum phase transition]]<br />
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* [[Quantum computing]]<br />
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* [[Quantum network]]<br />
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Category:Quantum information science<br />
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类别: 量子信息科学<br />
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* [[Quantum pseudo-telepathy]]<br />
<br />
Category:Quantum mechanics<br />
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类别: 量子力学<br />
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* [[Quantum teleportation]]<br />
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Category:Unsolved problems in physics<br />
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类别: 物理学中未解决的问题<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Quantum entanglement]]. Its edit history can be viewed at [[量子纠缠/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%87%8F%E5%AD%90%E7%BA%A0%E7%BC%A0&diff=21256量子纠缠2021-01-24T13:12:32Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译。<br />
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{{short description|Correlation between measurements of quantum subsystems, even when spatially separated}}<br />
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[[File:SPDC figure.png|right|thumb|275px|[[Spontaneous parametric down-conversion]] process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[[Spontaneous parametric down-conversion process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[自发参量下转换过程可以将光子分裂成具有相互垂直极化的 II 型光子对。]<br />
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{{Quantum mechanics|fundamentals}}<br />
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'''Quantum entanglement''' is a physical phenomenon that occurs when a pair or group of [[particle]]s are generated, interact, or share spatial proximity in a way such that the [[quantum state]] of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the [[principle of locality|disparity between classical and quantum physics]]: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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量子纠缠是一种物理现象,描述的是当一对或一组粒子被产生、相互作用或共享空间邻近性时(包括当粒子被大距离分离时),该对或该组粒子中的每个粒子的量子态都无法独立于其他粒子的态。量子纠缠是经典物理学和量子物理学之间差别悬殊的核心问题:纠缠是量子力学的一个主要特征,而经典力学却没有这种特征。<br />
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[[Measurement#Quantum mechanics|Measurements]] of [[physical properties]] such as [[position (vector)|position]], [[momentum]], [[spin (physics)|spin]], and [[polarization (waves)|polarization]] performed on entangled particles can, in some cases, be found to be perfectly [[correlated]]. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly [[paradox]]ical effects: any measurement of a property of a particle results in an irreversible [[wave function collapse]] of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a property of a particle results in an irreversible wave function collapse of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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在某些情况下,对纠缠粒子的位置、动量、自旋和偏振等物理性质的测量的结果可以是完全相关的。例如,如果一对纠缠粒子的产生使得它们的总自旋已知为零,并且我们发现一个粒子在第一个轴上具有顺时针自旋,那么在同一个轴上测量的另一个粒子的自旋将会是逆时针的。然而,这种行为产生了看似矛盾的效应:对粒子性质的任何测量都会导致该粒子的不可逆波函数崩溃,并将改变原来的量子态。在粒子纠缠的情况下,这样的测量将影响整个纠缠系统。<br />
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Such phenomena were the subject of a 1935 paper by [[Albert Einstein]], [[Boris Podolsky]], and [[Nathan Rosen]],<ref name="Einstein1935"><br />
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Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen, and several papers by Erwin Schrödinger shortly thereafter, describing what came to be known as the EPR paradox. Einstein and others considered such behavior to be impossible, as it violated the local realism view of causality (Einstein referring to it as "spooky action at a distance") and argued that the accepted formulation of quantum mechanics must therefore be incomplete.<br />
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这些现象是阿尔伯特·爱因斯坦、鲍里斯·波多尔斯基和纳森·罗森在1935年发表的一篇论文和埃尔文·薛定谔随后不久发表的几篇论文的主题,这些论文描述了后来的EPR悖论。爱因斯坦和其他人认为这样的行为是不可能的,因为它违反了因果关系的局部实在论观点(爱因斯坦称之为“远处的幽灵行为”),并认为量子力学的公认公式因此一定是不完整的。<br />
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{{cite journal|author=Einstein A, Podolsky B, Rosen N|last2=Podolsky|last3=Rosen|year=1935|title=Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?|journal=Phys. Rev.|volume=47|issue=10|pages=777–780|bibcode=1935PhRv...47..777E|doi=10.1103/PhysRev.47.777|doi-access=free}}<br />
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</ref> and several papers by [[Erwin Schrödinger]] shortly thereafter,<ref name="Schrödinger1935"><br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<br />
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然而,后来,量子力学的反直觉预测在实验上得到了验证。所谓的“无漏洞”钟试验已经进行,在这种试验中,粒子位置被分开,以光速进行的通信将花费更长的时间——在一次实验中比测量间隔长10000倍<br />
{{cite journal<br />
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|author=Schrödinger E<br />
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According to some interpretations of quantum mechanics, the effect of one measurement occurs instantly. Other interpretations which don't recognize wavefunction collapse dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces correlation between the measurements and that the mutual information between the entangled particles can be exploited, but that any transmission of information at faster-than-light speeds is impossible.<br />
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根据量子力学的一些解释,一次测量的效果是瞬间发生的。其他不承认波函数崩塌的解释则认为不存在任何“效应”。然而,所有的解释都同意,纠缠产生了测量之间的相关性,纠缠粒子之间的互信息可以被利用,但任何信息的传输速度都不可能超过光速。<br />
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|title=Discussion of probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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Quantum entanglement has been demonstrated experimentally with photons, neutrinos, electrons, molecules as large as buckyballs, and even small diamonds. The utilization of entanglement in communication, computation and quantum radar is a very active area of research and development.<br />
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量子纠缠已经在光子、中微子、电子、巴基球大小的分子,甚至小钻石的实验中得到证实。纠缠在通信、计算和量子雷达中的应用是一个非常活跃的研究和发展领域。<br />
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|volume=31<br />
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|issue=4<br />
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|pages=555–563<br />
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Article headline regarding the [[Einstein–Podolsky–Rosen paradox (EPR paradox) paper, in the May 4, 1935 issue of The New York Times.]]<br />
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文章标题关于[爱因斯坦-波多尔斯基-罗森悖论(EPR paradox)论文,发表于1935年5月4日的《纽约时报》]<br />
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|year=1935<br />
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|doi=10.1017/S0305004100013554<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.<br />
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1935年,阿尔伯特·爱因斯坦与鲍里斯·波多尔斯基和纳森·罗森在一篇联合论文中首次讨论了量子力学关于强关联系统的反直觉预测。 <br />
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|bibcode = 1935PCPS...31..555S }}</ref><ref name="Schrödinger1936"><br />
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{{cite journal |author=Schrödinger E<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated: Einstein later famously derided entanglement as "spukhafte Fernwirkung" or "spooky action at a distance."<br />
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此后不久,薛定谔发表了一篇影响深远的论文,定义并讨论了“纠缠”的概念在论文中,他承认了这个概念的重要性,并指出了爱因斯坦后来众所周知的对纠缠的嘲弄“幽灵般的超距作用”<br />
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|title=Probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously Bohm's interpretation of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when John Stewart Bell proved that one of their key assumptions, the principle of locality, as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是Bohm对量子力学的解释),但发表的其他工作相对较少。尽管如此,直到1964年,约翰·斯图尔特·贝尔(John Stewart Bell)证明了他们的一个关键假设,即应用于EPR所希望的隐变量解释的局部性原理,在数学上与量子理论的预测不一致,EPR的论点中的弱点至此才被发现。<br />
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|volume=32<br />
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|issue=3<br />
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Specifically, Bell demonstrated an upper limit, seen in Bell's inequality, regarding the strength of correlations that can be produced in any theory obeying local realism, and showed that quantum theory predicts violations of this limit for certain entangled systems. His inequality is experimentally testable, and there have been numerous relevant experiments, starting with the pioneering work of Stuart Freedman and John Clauser in 1972 and Alain Aspect's experiments in 1982. An early experimental breakthrough was due to Carl Kocher, Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles. Alain Aspect notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / superdeterminism loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<br />
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具体来说,贝尔证明了一个上限,可以在贝尔不等式中看到,关于遵循局部实在论的任何理论中可以产生的关联强度,并表明量子理论预测某些纠缠系统会违反这个极限。从1972年斯图亚特·弗里德曼和约翰·克劳瑟的开创性工作和1982年阿兰·阿斯佩的实验开始,他的不等式在实验上是可以检验的,并且存在许多相关的实验。早期的实验突破归功于卡尔·科彻,科彻的仪器配备了更好的偏振器,弗里德曼和克劳瑟使用了这种仪器,他们可以证实余弦平方依赖性,并用它来证明对一组固定角度的贝尔不等式的违反。阿兰·阿斯佩指出的则是“设置独立漏洞”——他称之为“牵强的”,然而,“不可忽视”的“剩余漏洞”——还没有被关闭,并且自由意志/超决定论的漏洞是无法弥补的;他说“没有任何实验,尽可能的理想情况,可以说是完全没有漏洞的。” <br />
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|pages=446–452<br />
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|year=1936<br />
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A minority opinion holds that although quantum mechanics is correct, there is no superluminal instantaneous action-at-a-distance between entangled particles once the particles are separated.<br />
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少数人认为,尽管量子力学是正确的,但是一旦粒子分离,纠缠的粒子之间并不存在超光速瞬时作用。<br />
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|doi=10.1017/S0305004100019137<br />
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|bibcode = 1936PCPS...32..446S }}<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of quantum key distribution protocols, most famously BB84 by Charles H. Bennett and Gilles Brassard and E91 by Artur Ekert. Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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贝尔的工作提出了利用这些超强相关性作为交流资源的可能性。它导致了1984年量子密钥分配协议的发现,其中最著名的是查尔斯·H·班纳特和吉尔斯 布拉萨德的BB84和艾特 艾克特的E91。虽然BB84不使用纠缠,但是艾克特的协议使用了对Bell不等式的违反作为安全性的证明。 <br />
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</ref> describing what came to be known as the [[EPR paradox]]. Einstein and others considered such behavior to be impossible, as it violated the [[local realism]] view of causality (Einstein referring to it as "spooky [[action at a distance]]")<ref>Physicist John Bell depicts the Einstein camp in this debate in his article entitled "Bertlmann's socks and the nature of reality", p. 143 of ''Speakable and unspeakable in quantum mechanics'': "For EPR that would be an unthinkable 'spooky action at a distance'. To avoid such action at a distance they have to attribute, to the space-time regions in question, real properties in advance of observation, correlated properties, which predetermine the outcomes of these particular observations. Since these real properties, fixed in advance of observation, are not contained in quantum formalism, that formalism for EPR is incomplete. It may be correct, as far as it goes, but the usual quantum formalism cannot be the whole story." And again on p. 144 Bell says: "Einstein had no difficulty accepting that affairs in different places could be correlated. What he could not accept was that an intervention at one place could influence, immediately, affairs at the other." Downloaded 5 July 2011 from {{cite book |year=1987 |accessdate=2014-06-14 |title=Speakable and Unspeakable in Quantum Mechanics |first=J. S. |last=Bell |publisher=[[CERN]] |isbn=0521334950 |url=http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20150412044550/http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |archivedate=12 April 2015 |df=dmy-all }}</ref> and argued that the accepted formulation of [[quantum mechanics]] must therefore be incomplete.<br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally<ref name=":0" /><ref name=":1" /><ref name=":2" /> in tests in which polarization or spin of entangled particles were measured at separate locations, statistically violating [[Bell's inequality]]. In earlier tests, it couldn't be absolutely ruled out that the test result at one point could have been [[Loopholes in Bell test experiments|subtly transmitted]] to the remote point, affecting the outcome at the second location.<ref name=":2">Francis, Matthew.<br />
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[https://arstechnica.com/science/2012/10/quantum-entanglement-shows-that-reality-cant-be-local/ Quantum entanglement shows that reality can't be local], ''Ars Technica'', 30 October 2012</ref> However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<ref name=":1">{{cite journal|last1=Matson|first1=John|title=Quantum teleportation achieved over record distances|journal=Nature News|date=13 August 2012|doi=10.1038/nature.2012.11163|s2cid=124852641}}</ref><ref name=":0">{{cite journal<br />
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| title =Bounding the speed of 'spooky action at a distance<br />
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An entangled system is defined to be one whose quantum state cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or superposition, of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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一个纠缠系统被定义为一个量子态不能被分解为其局部成分的态的乘积的系统,也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部组分状态积的和或叠加;如果这个和必然有多个项,它就被纠缠。<br />
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| journal =Physical Review Letters |volume=110 | issue =26 |page=260407<br />
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| year =2013<br />
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Quantum systems can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on methods. Entanglement is broken when the entangled particles decohere through interaction with the environment; for example, when a measurement is made.<br />
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量子系统可以通过各种类型的相互作用而纠缠在一起。为了实验的目的,纠缠可以通过一些方法实现,请参见下面的方法部分。当纠缠的粒子通过与环境的相互作用而退离时,例如在进行测量时,纠缠就被打破了。 <br />
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| arxiv =1303.0614<br />
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| bibcode =2013PhRvL.110z0407Y<br />
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As an example of entanglement: a subatomic particle decays into an entangled pair of other particles. The decay events obey the various conservation laws, and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a spin-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be spin up on some axis, the other, when measured on the same axis, is always found to be spin down. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the singlet state.)<br />
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作为纠缠的一个例子:一个亚原子粒子衰变为一对纠缠的其他粒子。衰变事件遵循各种守恒定律,因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(以便总动量、角动量、能量等在此过程前后保持大致相同)。例如,一个自旋为零的粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量到自旋向上时,另一个粒子在同一个轴上被测量时,总是被发现是自旋向下。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于单线态)。<br />
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| doi = 10.1103/PhysRevLett.110.260407<br />
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| pmid =23848853 | last1 =Yin | first1 =Juan | last2 =Cao | first2 =Yuan | last3 =Yong | first3 =Hai-Lin | last4 =Ren | first4 =Ji-Gang | last5 =Liang | first5 =Hao | last6 =Liao | first6 =Sheng-Kai | last7 =Zhou | first7 =Fei | last8 =Liu | first8 =Chang | last9 =Wu | first9 =Yu-Ping | last10 =Pan | first10 =Ge-Sheng | last11 =Li | first11 =Li | last12 =Liu | first12 =Nai-Le | last13 =Zhang | first13 =Qiang | last14 =Peng | first14 =Cheng-Zhi | last15 =Pan | first15 =Jian-Wei | s2cid =119293698 }}</ref><br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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如果将这两种粒子分开,可以更好地观察到纠缠的特性。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫。现在,如果我们测量其中一个粒子的特性(比如自旋) ,得到一个结果,然后用同样的标准(沿着同样的轴自旋)测量另一个粒子,我们发现第二个粒子的测量结果将匹配(在补充意义上)第一个粒子的测量结果,因为它们的值将相反。<br />
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According to ''some'' [[interpretations of quantum mechanics]], the effect of one measurement occurs instantly. Other interpretations which don't recognize [[wavefunction collapse]] dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces ''[[correlation]]'' between the measurements and that the [[mutual information]] between the entangled particles can be exploited, but that any ''transmission'' of information at faster-than-light speeds is impossible.<ref>[[Roger Penrose]], ''The Road to Reality: A Complete Guide to the Laws of the Universe'', London, 2004, p. 603.</ref><ref name="Griffiths2004">{{citation | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |isbn= 978-0-13-111892-8}}</ref><br />
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根据“一些”[[量子力学的解释]],一次测量的效果瞬间发生。其他不承认[[波函数崩溃]]的解释则认为存在任何“效应”。然而,所有的解释都同意,纠缠在测量值之间产生了“[[相关]]”,并且纠缠粒子之间的[[互信息]]可以被利用,但是任何以高于光速的信息“传输”都是不可能的。 <br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a hidden variable theory (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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上述结果可能会或不会被认为是令人惊讶的。一个经典系统也会表现出同样的性质,而一个隐藏变量理论(见下文)肯定会被要求这样做,它建立在经典力学和量子力学的角动量守恒的基础上。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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Quantum entanglement has been demonstrated experimentally with [[photon]]s,<ref name="Kocher1">{{cite journal | doi = 10.1103/PhysRevLett.18.575 | volume=18 | issue=15 | title=Polarization Correlation of Photons Emitted in an Atomic Cascade | journal=Physical Review Letters | pages=575–577 | last1 = Kocher | first1 = CA | last2 = Commins | first2 = ED | year=1967| url=http://www.escholarship.org/uc/item/1kb7660q | bibcode=1967PhRvL..18..575K }}</ref><ref name="Kocherphd">Carl A. Kocher, Ph.D. Thesis (University of California at Berkeley, 1967). ''[https://escholarship.org/uc/item/1kb7660q Polarization Correlation of Photons Emitted in an Atomic Cascade]''</ref> [[neutrino]]s,<ref>J. A. Formaggio, D. I. Kaiser, M. M. Murskyj, and T. E. Weiss (2016), "[https://journals.aps.org/prl/accepted/6f072Y00C3318d41f5739ec7f83a9acf1ad67b002 Violation of the Leggett-Garg inequality in neutrino oscillations]". ''Phys. Rev. Lett.'' Accepted 23 June 2016.</ref> [[electron]]s,<ref name="NTR-20151021">{{cite journal |author=Hensen, B. |title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres |date=21 October 2015 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature15759 |display-authors=etal |volume=526 |issue=7575 |pages=682–686|bibcode = 2015Natur.526..682H |pmid=26503041|arxiv=1508.05949 |hdl=2117/79298 |s2cid=205246446 }} See also [http://www.nature.com/articles/nature15759.epdf?referrer_access_token=1QB20mTNTZW60nEXil0D79RgN0jAjWel9jnR3ZoTv0Pfu6MWINxm4Io03p2jIRZ8qX_3I3N0Kr-AlItuikCZOJrG8QbdRRghlecFwmixlbQpWuw1dtaib4Le5DQOG3u_aXHU85x1JEhOcQTa1sHi0yvW23bblxmEQZAmHL4G0gIVusG_6JWorroY5BprgbTl4FiaE8WltEgMoUMZfZBkEfbMcFDp5iR112TFx_x3ZRj88Wa23E2moEvTfKjtlued0&tracking_referrer=www.nytimes.com free online access version].</ref><ref name="NYT-20151021">{{cite news |last=Markoff |first=Jack |title=Sorry, Einstein. Quantum Study Suggests 'Spooky Action' Is Real. |url=https://www.nytimes.com/2015/10/22/science/quantum-theory-experiment-said-to-prove-spooky-interactions.html |date=21 October 2015 |work=The New York Times |accessdate=21 October 2015 }}</ref> [[molecule]]s as large as [[buckyball]]s,<ref>{{cite journal | doi = 10.1038/44348 | title = Wave–particle duality of C<sub>60</sub> molecules | date= 14 October 1999 | volume=401 | issue = 6754 | journal=Nature | pages=680–682 | pmid=18494170|bibcode = 1999Natur.401..680A | last1 = Arndt | first1 = M | last2 = Nairz | first2 = O | last3 = Vos-Andreae | first3 = J | last4 = Keller | first4 = C | last5 = van der Zouw | first5 = G | last6 = Zeilinger | first6 = A| s2cid = 4424892 }} {{subscription}}</ref><ref>[[Olaf Nairz]], [[Markus Arndt]], and [[Anton Zeilinger]], "Quantum interference experiments with large molecules", American Journal of Physics, 71 (April 2003) 319–325.</ref> and even small diamonds.<ref>{{cite journal |journal=Science |date=2 December 2011 |volume=334 |issue=6060 |pages=1253–1256 |doi=10.1126/science.1211914 |pmid=22144620 |url=http://www.sciencemag.org/content/334/6060/1253.full |title=Entangling macroscopic diamonds at room temperature |lay-url=https://www.newscientist.com/article/dn21235-entangled-diamonds-blur-quantumclassical-divide.html|bibcode = 2011Sci...334.1253L |last1=Lee |first1=K. C. |last2=Sprague |first2=M. R. |last3=Sussman |first3=B. J. |last4=Nunn |first4=J. |last5=Langford |first5=N. K. |last6=Jin |first6=X.- M. |last7=Champion |first7=T. |last8=Michelberger |first8=P. |last9=Reim |first9=K. F. |last10=England |first10=D. |last11=Jaksch |first11=D. |last12=Walmsley |first12=I. A. |s2cid=206536690 }}</ref><ref>[http://www.sciencemag.org/content/334/6060/1253/suppl/DC1 sciencemag.org], supplementary materials</ref> The utilization of entanglement in [[quantum communication|communication]], [[quantum computing|computation]] and [[quantum radar]] is a very active area of research and development.<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<br />
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矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能比光传播得快),因此确保纠缠对的另一部分的测量结果是“正确的”。在哥本哈根解释中,对其中一个粒子的自旋测量的结果是坍缩成一种状态,其中每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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== History 历史==<br />
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[[File:NYT May 4, 1935.jpg|right|thumb| 250px|Article headline regarding the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox) paper, in the May 4, 1935 issue of ''[[The New York Times]]''.]]<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, hence, any causal effect connecting the events would have to travel faster than light. According to the principles of special relativity, it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events and there are inertial frames in which is first and others in which is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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我们可以选择测量的距离和时间,以便使两次测量之间的间隔像空间一样,因此,连接事件的任何因果效应都必须比光传播得更快。根据狭义相对论的原理,任何信息都不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量值是第一个。对于两个分离的类空事件,存在惯性系,有惯性系在其中是第一位的,也有其他惯性系在其中是第一位的。因此,这两种测量之间的相关性不能解释为一种测量决定另一种测量:不同的观察者会对因果关系的作用产生分歧。<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by [[Albert Einstein]] in 1935, in a joint paper with [[Boris Podolsky]] and [[Nathan Rosen]].<ref name="Einstein1935"/><br />
1935年阿尔伯特 爱因斯坦与鲍里斯 波多斯基和纳兰 罗森在一篇联合论文中首次讨论了关于强关联系统的量子力学的反直觉预测。 <br />
(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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(事实上,即使没有纠缠,也会出现类似的悖论:单个粒子的位置分布在空间上,两个试图在两个不同位置检测粒子的大范围分离的探测器必须立即获得适当的相关性,这样它们就不会同时检测到粒子。)<br />
In this study, the three formulated the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox), a [[thought experiment]] that attempted to show that [[quantum mechanics|quantum mechanical theory]] was [[Incompleteness of quantum physics|incomplete]]. They wrote: "We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete."<ref name="Einstein1935"/><br />
在这项研究中,三人提出了[[爱因斯坦-波多尔斯基-罗森悖论]](EPR悖论),一个[[思维实验]],试图证明[[量子力学|量子力学理论]]是[[量子物理的不完全性|不完全性]]。他们写道:“因此,我们被迫得出结论,波函数给出的物理实在的量子力学描述并不完整。” <br />
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However, the three scientists did not coin the word ''entanglement'', nor did they generalize the special properties of the state they considered. Following the EPR paper, [[Erwin Schrödinger]] wrote a letter to Einstein in [[German language|German]] in which he used the word ''Verschränkung'' (translated by himself as ''entanglement'') "to describe the correlations between two particles that interact and then separate, as in the EPR experiment."<ref name=MK>Kumar, M., ''Quantum'', Icon Books, 2009, p. 313.</ref><br />
然而,这三位科学家并没有创造“纠缠”这个词,也没有概括出他们所考虑的状态的特殊性质。在EPR论文发表之后,[[埃尔温·薛定谔]]用德语给爱因斯坦写了一封信,信中他用“Verschränkung”(他自己翻译为“纠缠”)一词来描述两个相互作用然后分离的粒子之间的关联,就像EPR实验中那样。” <br />
A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables". The state of the particles being measured contains some hidden variables, whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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解决这一悖论的一个可能办法是假设量子理论是不完整的,测量结果取决于预先确定的“隐藏变量”。被测粒子的状态包含一些隐藏的变量,这些变量的值从分离的那一刻起就有效地决定了自旋测量的结果。这就意味着每个粒子都携带着所需的全部信息,在测量时不需要从一个粒子传输到另一个粒子。爱因斯坦和其他人(见上一节)最初认为这是摆脱悖论的唯一途径,而公认的量子力学描述(带有随机测量结果)肯定是不完整的。<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated:<ref name="Schrödinger1935"/> "I would not call [entanglement] ''one'' but rather ''the'' characteristic trait of [[quantum mechanics]], the one that enforces its entire departure from [[Classical mechanics|classical]] lines of thought."<br />
此后不久,薛定谔发表了一篇开创性的论文,对“纠缠”的概念进行了定义和讨论。在论文中,他认识到了这个概念的重要性,并指出:“我不会将[纠缠]称为‘一’,而是称之为[量子力学]的‘特性’。”,它完全背离了[[经典力学|经典]]的思路。” <br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the local realist or hidden variables view were correct, the results would always satisfy Bell's inequality. A number of experiments have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists. When measurements of the entangled particles are made in moving relativistic reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<br />
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然而,当考虑沿不同轴的纠缠粒子自旋的测量时,局部隐变量理论是失败的。如果进行了大量成对的此类测量(在大量成对的纠缠粒子上),那么在统计上,如果局部现实主义或隐藏变量的观点是正确的,结果将始终满足贝尔不等式。大量的实验表明,贝尔不等式在实践中是不成立的。然而,在2015年之前,被物理学家群体认为是最关键的是所有这些实践都有漏洞问题,。当在运动的相对论参考系中对纠缠粒子进行测量时,每个测量(在它自己的相对论时间范围内)都发生在另一个之前,测量结果将保持相关。<br />
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Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the [[theory of relativity]].<ref>Alisa Bokulich, Gregg Jaeger, ''Philosophy of Quantum Information and Entanglement'', Cambridge University Press, 2010, xv.</ref> Einstein later famously derided entanglement as "''spukhafte Fernwirkung''"<ref name="spukhafte">Letter from Einstein to Max Born, 3 March 1947; ''The Born-Einstein Letters; Correspondence between Albert Einstein and Max and Hedwig Born from 1916 to 1955'', Walker, New York, 1971. (cited in {{citation | title = Quantum Entanglement and Communication Complexity (1998) | journal = SIAM J. Comput. | volume = 30 | issue = 6 | citeseerx = 10.1.1.20.8324 | author = M. P. Hobson |pages=1829–1841 | display-authors = etal | year = 1998 }})</ref> or "spooky [[Action at a distance (physics)|action at a distance]]."<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are incompatible in the sense that these measurements' maximum simultaneous precision is constrained by the uncertainty principle. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations, and thus entanglement is a fundamentally non-classical phenomenon.<br />
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沿不同轴线测量自旋的基本问题是,这些测量不可能同时具有确定的值——它们是不相容的,因为这些测量的最大同时精度受到不确定性原理的限制。这与经典物理学中的发现相反,在经典物理学中,任何数量的性质都可以以任意精度同时测量。从数学上证明了相容测量不能显示违反贝尔不等式的关联,因此纠缠是一个基本的非经典现象。<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously [[De Broglie–Bohm theory|Bohm's interpretation]] of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when [[John Stewart Bell]] proved that one of their key assumptions, the [[principle of locality]], as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是量子力学的[[De Broglie–Bohm 理论 | Bohm表达]]),但其他发表的著作相对较少。尽管有人对此感兴趣,但直到1964年,[[约翰·斯图尔特·贝尔]]证明了他们的一个关键假设,[[局域性原理]],即应用于EPR希望解释的隐藏变量,在数学上与量子理论的预测不一致时,EPR论点中的漏洞才被发现。<br />
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Entanglement is required to preserve the Uncertainty principle, as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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纠缠是保持不确定性原理所必需的,如 EPR 悖论所示。例如,假设一个高能光子衰变成一个电子/正电子对,然后测量电子的位置和正电子的动量。如果我们在物理描述中不允许纠缠,那么每个粒子的位置和动量就可以通过参考动量守恒来推导,这就违反了测不准原理。或者,如果我们要求不确定性原理保持真实,而仍然不允许在物理上描述对的纠缠,不确定性原理将会违反动量守恒定律,因为在位置和动量上强相关性是不可能的(也就是说,人们不能有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关)。--><br />
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Specifically, Bell demonstrated an upper limit, seen in [[Bell's inequality]], regarding the strength of correlations that can be produced in any theory obeying [[local realism]], and showed that quantum theory predicts violations of this limit for certain entangled systems.<ref>{{cite journal |author = J. S. Bell |title = On the Einstein-Poldolsky-Rosen paradox |journal = Physics Physique Физика |volume = 1 |issue = 3 |pages = 195–200 |year = 1964|doi = 10.1103/PhysicsPhysiqueFizika.1.195 |doi-access = free }}</ref> His inequality is experimentally testable, and there have been numerous [[Bell test experiments|relevant experiments]], starting with the pioneering work of [[Stuart Freedman]] and [[John Clauser]] in 1972<ref name="Clauser">{{cite journal|doi=10.1103/PhysRevLett.28.938|last1=Freedman|first1=Stuart J.|last2=Clauser|first2=John F.|title=Experimental Test of Local Hidden-Variable Theories|journal=Physical Review Letters |volume=28 |issue=14 |pages=938–941|year=1972 |bibcode=1972PhRvL..28..938F|url=https://escholarship.org/uc/item/2f18n5nk}}</ref> and [[Alain Aspect]]'s experiments in 1982.<ref>{{cite journal |author1=A. Aspect |author2=P. Grangier |author3=G. Roger |name-list-style=amp |title = Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell's Inequalities |journal = Physical Review Letters |volume = 49 |issue = 2 |pages = 91–94 |year = 1982 |doi = 10.1103/PhysRevLett.49.91 |bibcode=1982PhRvL..49...91A|doi-access = free }}</ref> An early experimental breakthrough was due to Carl Kocher,<ref name="Kocher1"/><ref name="Kocherphd"/> who already in 1967 presented an apparatus in which two photons successively emitted from a calcium atom were shown to be entangled – the first case of entangled visible light. The two photons passed diametrically positioned parallel polarizers with higher probability than classically predicted but with correlations in quantitative agreement with quantum mechanical calculations. He also showed that the correlation varied only upon (as cosine square of) the angle between the polarizer settings<ref name="Kocherphd"/> and decreased exponentially with time lag between emitted photons.<ref name="Kocher2">{{cite journal | doi = 10.1016/0003-4916(71)90159-X | volume=65 | issue=1 | title=Time correlations in the detection of successively emitted photons | journal=Annals of Physics | pages=1–18 | last1 = Kocher | first1 = CA | year=1971| bibcode=1971AnPhy..65....1K }}</ref> Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles.<ref name="Clauser"/> All these experiments have shown agreement with quantum mechanics rather than the principle of local realism.<br />
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For decades, each had left open at least one [[Loopholes in Bell test experiments|loophole]] by which it was possible to question the validity of the results. However, in 2015 an experiment was performed that simultaneously closed both the detection and locality loopholes, and was heralded as "loophole-free"; this experiment ruled out a large class of local realism theories with certainty.<ref name="hanson">{{cite journal|last1=Hanson|first1=Ronald|title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres|journal=Nature|volume=526|issue=7575|pages=682–686|doi=10.1038/nature15759|arxiv=1508.05949|bibcode = 2015Natur.526..682H|pmid=26503041|year=2015|s2cid=205246446}}</ref> [[Alain Aspect]] notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / ''[[superdeterminism]]'' loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<ref>{{Cite journal | title=Viewpoint: Closing the Door on Einstein and Bohr's Quantum Debate| journal=Physics| volume=8| date=2015-12-16| last1=Aspect| first1=Alain| page=123| doi=10.1103/physics.8.123| doi-access=free| bibcode=2015PhyOJ...8..123A}}</ref><br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time. The authors claimed that this result was achieved by entanglement swapping between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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在2012年和2013年的实验中,在时间上从未共存的光子之间产生了偏振关联。作者认为,这一结果是在测量了一对纠缠光子的偏振态后,通过两对纠缠光子之间的纠缠交换得到的,证明了量子非定域性不仅适用于空间,也适用于时间。 <br />
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A minority opinion holds that although quantum mechanics is correct, there is no [[faster-than-light|superluminal]] instantaneous action-at-a-distance between entangled particles once the particles are separated.<ref>{{Cite journal |doi = 10.1142/S0217979206034078|title = Correlations in Entangled States|journal = International Journal of Modern Physics B|volume = 20|issue = 11n13|pages = 1496–1503|year = 2006|last1 = Sanctuary|first1 = B. C|arxiv = quant-ph/0508238|bibcode = 2006IJMPB..20.1496S|s2cid = 119403050}}</ref><ref>{{Cite arxiv |eprint = quant-ph/0404011 |last1 = Yin |first1 = Juan |title = The Statistical Interpretation of Entangled States |last2 = Cao |first2 = Yuan |last3 = Yong |first3 = Hai-Lin |last4 = Ren |first4 = Ji-Gang |last5 = Liang |first5 = Hao |last6 = Liao |first6 = Sheng-Kai |last7 = Zhou |first7 = Fei |last8 = Liu |first8 = Chang |last9 = Wu |first9 = Yu-Ping |last10 = Pan |first10 = Ge-Sheng |last11 = Zhang |first11 = Qiang |last12 = Peng |first12 = Cheng-Zhi |last13 = Pan |first13 = Jian-Wei |year = 2004 }}</ref><ref>{{cite journal|doi=10.1002/prop.201600044 | volume=65 | issue=6–8 | title=After Bell | year=2016 | journal=Fortschritte der Physik | page=1600044 | last1 = Khrennikov | first1 = Andrei}}</ref><ref>{{Cite journal |arxiv = 1603.08674|last1 = Yin|first1 = Juan|title = After Bell|journal = Fortschritte der Physik (Progress in Physics)|date=2017|volume = 65|issue = 1600014|pages = 6–8|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|bibcode = 2016arXiv160308674K}}</ref><ref>{{Cite journal |arxiv = quant-ph/0703251|last1 = Yin|first1 = Juan|title = Classical statistical distributions can violate Bell-type inequalities|journal = Journal of Physics A: Mathematical and Theoretical|volume = 41|issue = 8|pages = 085303|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|year = 2007|doi = 10.1088/1751-8113/41/8/085303|s2cid = 46193162}}</ref><br />
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In three independent experiments in 2013 it was shown that classically communicated separable quantum states can be used to carry entangled states. The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<br />
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2013年的三个独立实验表明,经典通信的可分离量子态可以用来携带纠缠态。第一次无漏洞贝尔试验于2015年在图代尔夫特举行,证实了贝尔不等式的不成立。 <br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of [[quantum key distribution]] protocols, most famously [[BB84]] by [[Charles H. Bennett (computer scientist)|Charles H. Bennett]] and [[Gilles Brassard]]<ref>C. H. Bennett and G. Brassard. "Quantum cryptography: Public key distribution and coin tossing". In ''Proceedings of IEEE International Conference on Computers, Systems and Signal Processing'', volume 175, p. 8. New York, 1984. http://researcher.watson.ibm.com/researcher/files/us-bennetc/BB84highest.pdf</ref> and [[E91 protocol|E91]] by [[Artur Ekert]].<ref>{{cite journal|last=Ekert|first=A.K.|authorlink=Artur Ekert|title=Quantum cryptography based on Bell's theorem|journal=Phys. Rev. Lett.|volume=67|issue=6|year=1991|doi=10.1103/PhysRevLett.67.661|issn=0031-9007|bibcode = 1991PhRvL..67..661E|pmid=10044956|pages=661–663}}</ref> Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<br />
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2014年8月,巴西研究人员加布里埃拉·巴雷托·莱莫斯和他的团队能够使用光子“拍摄”物体,这些光子并没有与实验对象发生相互作用,而是与这些物体发生了纠缠。来自维也纳大学的勒莫斯相信,这种新的量子成像技术可以在微光成像势在必行的领域找到应用,比如生物或医学成像。<br />
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== Concept 概念==<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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2015年,哈佛大学的马克斯·格雷纳团队直接测量了超冷玻色子原子系统中的Renyi纠缠。<br />
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=== Meaning of entanglement纠缠的意义 ===<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<br />
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从2016年起,IBM、微软等多家公司成功创建了量子计算机,并允许开发人员和技术爱好者公开实验量子力学的概念,这其中就包括量子纠缠。 <br />
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An entangled system is defined to be one whose [[quantum state]] cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or [[quantum superposition|superposition]], of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
纠缠系统被定义为其[[量子态]]不能被分解为其局部成分的态的乘积;也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部成分的状态积的和,或[[量子叠加|叠加]],如果这个和一定有一个以上的项,那么它是纠缠的。<br />
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Quantum [[physical system|systems]] can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on [[#Methods of creating entanglement|methods]]. Entanglement is broken when the entangled particles [[quantum decoherence|decohere]] through interaction with the environment; for example, when a measurement is made.<ref name="Peres1993">Asher Peres, ''[[Quantum Theory: Concepts and Methods]]'', Kluwer, 1993; {{ISBN|0-7923-2549-4}} p. 115.</ref><br />
量子[[物理系统|系统]]可以通过各种类型的相互作用而纠缠在一起。为了实验目的而实现纠缠的一些方法,请参见下面关于[[#创建纠缠的方法|方法]]的部分。当纠缠粒子通过与环境的相互作用[[量子退相干|退相干]]时,例如在进行测量时,纠缠将被打破。<br />
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There have been suggestions to look at the concept of time as an emergent phenomenon that is a side effect of quantum entanglement.<br />
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有人建议把时间的概念看作是量子纠缠的副作用的一种自然现象。<br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by Don Page and William Wootters in 1983.<br />
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换句话说,时间是一种纠缠现象,它将所有相等的时钟读数(正确准备的时钟或任何可用作时钟的物体的读数)放入同一个历史中。1983年,唐·佩奇和威廉·伍特斯首次提出了这一理论<br />
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As an example of entanglement: a [[subatomic particle]] [[Particle decay|decays]] into an entangled pair of other particles. The decay events obey the various [[conservation laws]], and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a [[Spin (physics)|spin]]-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be [[Spin (physics)#Direction|spin up]] on some axis, the other, when measured on the same axis, is always found to be [[Spin (physics)#Direction|spin down]]. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the [[singlet state]].)<br />
作为纠缠的一个例子:一个[[亚原子粒子]][[粒子衰变|衰变]]变成一对纠缠的其他粒子。衰变事件遵循各种[[守恒定律]],因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(因此总动量、角动量、能量等在此过程前后保持大致相同)。例如,[[自旋(物理)|自旋]]-零粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量为[[自旋(物理)方向|自旋向上]],另一个粒子在同一个轴上被测量时,总是被发现为[[自旋(物理)#方向|自旋向下]]。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于[[单态]]。)<br />
The Wheeler–DeWitt equation that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<br />
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20世纪60年代,惠勒-德威特方程引入了广义相对论和量子力学的概念,并于1983年再次引入,当时佩奇和伍特基于量子纠缠方程提出了一个解决方案。佩奇和伍特斯认为纠缠态可以用来测量时间。<br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
将这两个粒子分开,可以更好地观察到纠缠的特殊性质。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫(把这当成一个思维实验,而不是实际的实验)。现在,如果我们测量其中一个粒子的特定特性(例如,自旋),得到一个结果,然后使用相同的标准测量另一个粒子(沿相同的轴自旋),我们发现第二个粒子的测量结果将与第一个粒子的测量结果相匹配(在互补意义上)粒子,因为它们的值是相反的<br />
In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts. The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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2013年,在意大利都灵的国家理查尔卡计量研究所(INRIM) ,研究人员对佩奇和伍特的想法进行了首次实验测试。他们的结果被解释为证实了对于内部观察者来说时间是一种涌现的现象,但正如惠勒-德威特方程所预测的那样,对于宇宙的外部观察者来说时间是不存在的。纠缠的方法是从因果时间箭头的角度出发,假设一个粒子被测量的原因决定了另一个粒子测量结果的效应。<br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a [[hidden variable theory]] (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
上述结果可能会或不会被认为是令人惊讶的。一个经典系统将显示出相同的性质,而[[隐藏变量理论]](见下文)肯定需要这样做,基于经典和量子力学中的角动量守恒。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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===Paradox矛盾===<br />
Based on AdS/CFT correspondence, Mark Van Raamsdonk suggested that spacetime arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time. Induced gravity can emerge from the entanglement first law.<br />
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基于AdS/CFT对应关系, Mark Van Raamsdonk提出时空是量子自由度的一种涌现现象,量子自由度纠缠在时空的边界上。诱导引力可以从纠缠第一定律中产生。<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel [[faster than light]]) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the [[Copenhagen interpretation]], the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<ref>{{cite book|last1=Rupert W.|first1=Anderson|title=The Cosmic Compendium: Interstellar Travel|date=28 March 2015|publisher=The Cosmic Compendium|isbn=9781329022027|page=100|edition=First|url=https://books.google.com/books?id=JxauCQAAQBAJ&pg=PA100&lpg=PA100&dq=The+outcome+is+taken+to+be+random,+with+each+possibility+having+a+probability+of+50%25.+However,+if+both+spins+are+measured+along+the+same+axis,+they+are+found+to+be+anti-correlated.+This+means+that+the+random+outcome+of+the+measurement+made+on+one+particle+seems+to+have+been+transmitted+to+the+other,+so+that+it+can+make+the+%22right+choice%22+when+it+too+is+measured#v=onepage}}</ref><br />
矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能传播[[比光更快]]),从而确保纠缠对的另一部分的测量的“正确”结果。在[[哥本哈根解释]]中,其中一个粒子的自旋测量结果是坍缩成一种状态,在这种状态下,每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements [[spacelike]], hence, any causal effect connecting the events would have to travel faster than light. According to the principles of [[special relativity]], it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events {{math|''x''<sub>1</sub>}} and {{math|''x''<sub>2</sub>}} there are [[inertial frame]]s in which {{math|''x''<sub>1</sub>}} is first and others in which {{math|''x''<sub>2</sub>}} is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
可以选择测量的距离和时间,以便使两次测量之间的间隔[[类太空]],因此,任何与事件相关的因果效应都必须比光传播得更快。根据[[狭义相对论]]的原理,任何信息不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量值是第一个。对于两个类空分离事件{{math |''x'<sub>1</sub>}和{math |''x'<sub>2</sub>}存在[[惯性系]],其中{{math |''x'<sub>1</sub>}是第一个,而其他事件中{math |''x'<sub>2</sub>}是第一个。因此,这两种测量之间的相关性不能解释为一种测量决定另一种测量:不同的观察者会对因果关系的作用产生分歧。 <br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations. A well-known example is the Werner states that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables. Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<br />
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在媒体和大众科学中,量子非定域性常常被描述为与纠缠等价。虽然这对于纯二部量子态是正确的,但一般来说纠缠只对非局域关联是必要的,但是存在不产生这种关联的混合纠缠态。一个著名的例子是沃纳态,它纠缠在<math>p{sym}</math>的某些值上,但总是可以用局部隐藏变量来描述。此外,研究还表明,对于任意数目的当事方,存在真正纠缠但允许局部模型的态。<br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all distillable states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<br />
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上述关于局部模型存在性的证明假设一次只有一个量子态的副本可用。如果允许当事方对这些态的许多副本进行局部测量,那么许多明显的局部态(例如量子比特-沃纳态)就不能再由局部模型来描述。这尤其适用于所有蒸馏态。然而,当有足够多的拷贝时,所有的纠缠态是否都变成非局域态仍是一个悬而未决的问题。<br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
(事实上,即使没有纠缠,也会出现类似的悖论:单个粒子的位置分布在空间上,两个试图在两个不同位置检测粒子的大范围分离的探测器必须立即获得适当的相关性,这样它们就不会同时检测到粒子。)<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to quantum teleportation and to superdense coding, whereas non-locality is defined according to experimental statistics and is much more involved with the foundations and interpretations of quantum mechanics.<br />
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简言之,双方共享的一个状态的纠缠是必要的,但不足以使该状态成为非局部的。必须认识到,纠缠更普遍地被视为一个代数概念,因为它是非定域性、量子隐形传态和超密集编码的先决条件,而非定域性是根据实验统计定义的,它更多地涉及到量子力学的基础和解释。<br />
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=== Hidden variables theory 隐藏变量理论===<br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables".<ref>{{Cite news|url=https://www.scientificamerican.com/article/cosmic-test-bolsters-einsteins-ldquo-spooky-action-at-a-distance-rdquo/?WT.mc_id=SA_FB_PHYS_NEWS|title=Cosmic Test Bolsters Einstein's "Spooky Action at a Distance"|last=magazine|first=Elizabeth Gibney, Nature|newspaper=Scientific American|language=en|access-date=2017-02-04}}</ref> The state of the particles being measured contains some [[hidden-variable theory|hidden variables]], whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of quantum mechanics, including familiarity with the formalism and theoretical framework developed in the articles: bra–ket notation and mathematical formulation of quantum mechanics.<br />
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以下小节是为那些对量子力学的形式化、数学描述有良好工作知识的人准备的,包括熟悉文章中发展的形式主义和理论框架:bra–ket符号和量子力学的数学公式。<br />
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=== Violations of Bell's inequality 贝尔不等式的违反===<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the [[local realism|local realist]] or hidden variables view were correct, the results would always satisfy [[Bell's inequality]]. A [[Bell test experiments|number of experiments]] have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists.<ref>{{citation |author1=I. Gerhardt |author2=Q. Liu |author3=A. Lamas-Linares |author4=J. Skaar |author5=V. Scarani |author6=V. Makarov |author7=C. Kurtsiefer |year=2011 |title=Experimentally faking the violation of Bell's inequalities |journal=Phys. Rev. Lett. |volume=107 |issue=17 |page=170404 |arxiv=1106.3224 |doi=10.1103/PhysRevLett.107.170404 |bibcode=2011PhRvL.107q0404G |pmid=22107491|s2cid=16306493 }}</ref><ref>{{cite journal | last1 = Santos | first1 = E | year = 2004 | title = The failure to perform a loophole-free test of Bell's Inequality supports local realism | url = | journal = Foundations of Physics | volume = 34 | issue = 11| pages = 1643–1673 | doi=10.1007/s10701-004-1308-z|bibcode = 2004FoPh...34.1643S | s2cid = 123642560 }}</ref> When measurements of the entangled particles are made in moving [[special relativity|relativistic]] reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<ref>{{cite journal |author = H. Zbinden |title = Experimental test of nonlocal quantum correlations in relativistic configurations |journal = Phys. Rev. A |volume = 63 |issue = 2 |pages = 22111 |doi = 10.1103/PhysRevA.63.022111|year = 2001|arxiv = quant-ph/0007009 |bibcode = 2001PhRvA..63b2111Z |display-authors = 1 |last2 = Gisin |last3 = Tittel |s2cid = 44611890 |url = http://archive-ouverte.unige.ch/unige:37034 }}</ref><ref name=LG>Some of the history of both referenced Zbinden, et al. experiments is provided in Gilder, L., ''The Age of Entanglement'', Vintage Books, 2008, pp. 321–324.</ref><br />
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Consider two arbitrary quantum systems and , with respective Hilbert spaces and . The Hilbert space of the composite system is the tensor product<br />
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考虑两个任意的量子系统,分别用Hilbert空间和(?)。复合系统的Hilbert空间是张量积 <br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are [[Incompatible observables|incompatible]] in the sense that these measurements' maximum simultaneous precision is constrained by the [[uncertainty principle]]. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations,<ref>{{cite journal|last1=Cirel'son|first1=B. S.|title=Quantum generalizations of Bell's inequality|journal=Letters in Mathematical Physics|volume=4|issue=2|pages=93–100| year=1980|doi=10.1007/BF00417500|bibcode=1980LMaPh...4...93C|s2cid=120680226}}</ref> and thus entanglement is a fundamentally non-classical phenomenon.<br />
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<math> H_A \otimes H_B.</math><br />
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Entanglement is required to preserve the [[Uncertainty principle]], as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
纠缠是保持[[不确定性原理]]所必需的,如EPR悖论所示。例如,假设一个高能光子衰变成电子/正电子对,然后测量电子的位置和正电子的动量。如果在对的物理描述中不允许纠缠,那么每个粒子的位置和动量仍然可以通过动量守恒来推导,这违反了测不准原理。或者,如果我们要求测不准原理成立,并且仍然不允许在对的物理描述中纠缠,那么测不准原理将允许违反动量守恒定律,因为位置和动量之间的强相关性是不可能的(即人们无法有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关。--> <br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态 < math > scriptstyle | psi rangle _ a </math > ,而第二个系统处于状态 < math > scriptstyle | phi rangle _ b </math > ,则复合系统的状态为<br />
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=== Other types of experiments其他类型的试验 ===<br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time.<ref name="Xiao-song2012">{{cite journal |author=Xiao-song Ma, Stefan Zotter, Johannes Kofler, Rupert Ursin, Thomas Jennewein, Časlav Brukner & Anton Zeilinger |title=Experimental delayed-choice entanglement swapping |journal=Nature Physics |volume=8 |issue=6 |pages=480–485 |date=26 April 2012 |doi=10.1038/nphys2294|arxiv = 1203.4834 |bibcode = 2012NatPh...8..480M |last2=Zotter |last3=Kofler |last4=Ursin |last5=Jennewein |last6=Brukner |last7=Zeilinger |s2cid=119208488 }}</ref><ref>{{cite journal | last1 = Megidish | first1 = E. | last2 = Halevy | first2 = A. | last3 = Shacham | first3 = T. | last4 = Dvir | first4 = T. | last5 = Dovrat | first5 = L. | last6 = Eisenberg | first6 = H. S. | year = 2013 | title = Entanglement Swapping between Photons that have Never Coexisted | url = | journal = Physical Review Letters | volume = 110 | issue = 21| page = 210403| doi=10.1103/physrevlett.110.210403|arxiv = 1209.4191 |bibcode = 2013PhRvL.110u0403M | pmid=23745845| s2cid = 30063749 }}</ref> The authors claimed that this result was achieved by [[Quantum teleportation#Entanglement swapping|entanglement swapping]] between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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<math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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In three independent experiments in 2013 it was shown that [[classical physics|classically communicated]] [[separable state|separable quantum states]] can be used to carry entangled states.<ref>{{cite web|url=http://physicsworld.com/cws/article/news/2013/dec/11/classical-carrier-could-create-entanglement |title=Classical carrier could create entanglement |publisher=physicsworld.com |accessdate=2014-06-14|date=2013-12-11 }}</ref> The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<ref>{{cite web | url=http://hansonlab.tudelft.nl/loophole-free-bell-test/ | title=Loophole-free Bell test &#124; Ronald Hanson | access-date=24 October 2015 | archive-url=https://web.archive.org/web/20180704082456/http://hansonlab.tudelft.nl/loophole-free-bell-test/ | archive-date=4 July 2018 | url-status=dead }}</ref><br />
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States of the composite system that can be represented in this form are called separable states, or product states.<br />
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可以用这种形式表示的复合系统状态称为可分状态或乘积状态。<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<ref>{{Cite journal|url=http://www.nature.com/news/entangled-photons-make-a-picture-from-a-paradox-1.15781|title=Entangled photons make a picture from a paradox|journal=Nature|accessdate=13 October 2014|doi=10.1038/nature.2014.15781|year=2014|last1=Gibney|first1=Elizabeth|s2cid=124976589}}</ref><br />
2014年8月,巴西研究人员加布里埃拉·巴雷托·莱莫斯和他的团队能够用光子“拍摄”物体,这些光子并没有与受试者发生相互作用,而是与确实与这些物体发生相互作用的光子纠缠在一起。来自维也纳大学的莱莫斯相信,这种新的量子成像技术可以在生物或医学成像等领域的低光成像领域得到应用。<br />
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Not all states are separable states (and thus product states). Fix a basis <math>\scriptstyle \{|i \rangle_A\}</math> for and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for . The most general state in is of the form<br />
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并非所有的状态都是可分离的状态(因此产品状态也是如此)。修复的基础<math>\scriptstyle\{i\rangle\u a\}</math>,修复的基础<math>\scriptstyle\{j\rangle\u B\}</math>。最普遍的状态是 <br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
2015年,哈佛大学的马库斯 格瑞纳团队对超冷玻色子原子系统中的Renyi纠缠进行了直接测量。<br />
<math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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[数学] | psi rangle { AB } = sum { i,j } c { ij } | i rangle _ a otimes | j rangle _ b </math > 。<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<ref>{{Cite journal|last=Rozatkar|first=Gaurav|date=2018-08-16|title=Demonstration of quantum entanglement|url=https://osf.io/g8bpj/|journal=OSF|language=en}}</ref><br />
从2016年起,IBM、微软等多家公司成功创建了量子计算机,并允许开发人员和技术爱好者公开实验量子力学的概念,包括量子纠缠。<br />
This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > ,那么这种状态是可分的,因此 < math scriptstyle c { ij } = c ^ a _ ic ^ b _ j,</math > 产生 < math scriptstyle | psi rangle _ a = sum { i } c ^ a _ { i } | i } | i _ a </math > 和 < math > phi scriptstyle | b = sum { j } | j } | j rangle b = sum { j }。如果对于任何向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > 至少对于一对坐标 < math > scriptstyle c ^ a _ i,c ^ b _ j </math > 我们有 < math > scriptstyle c _ { ij } neq c ^ a _ ic ^ b _ j。如果一种状态是不可分割的,那么它被称为“纠缠态”。<br />
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=== Mystery of time 时间谜团===<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of , the following is an entangled state:<br />
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例如,给定两个基向量{ | 0 rangle _ a,| 1 rangle _ a } </math > 和两个基向量{ | 0 rangle _ b,| 1 rangle _ b } </math > ,下面是一个纠缠态:<br />
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There have been suggestions to look at the concept of time as an [[emergent phenomenon]] that is a side effect of quantum entanglement.<ref>{{Cite journal|title= Time from quantum entanglement: an experimental illustration|arxiv=1310.4691|bibcode = 2014PhRvA..89e2122M |doi = 10.1103/PhysRevA.89.052122|volume=89|issue= 5|pages=052122|journal=Physical Review A|year=2014 | last1 = Moreva | first1 = Ekaterina|s2cid=118638346}}</ref><ref>{{cite web|url=https://www.newscientist.com/article/dn24473-entangled-toy-universe-shows-time-may-be-an-illusion.html#.U8_-ApSSx2A|title=Entangled toy universe shows time may be an illusion|publisher=|accessdate=13 October 2014}}</ref><br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by [[Don Page (physicist)|Don Page]] and [[William Wootters]] in 1983.<ref>David Deutsch, The Beginning of infinity. Page 299</ref><br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right)<br />
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The [[Wheeler–DeWitt equation]] that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<ref name="medium.com">{{cite web|url=https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933|title=Quantum Experiment Shows How Time 'Emerges' from Entanglement|website=Medium|accessdate=13 October 2014|date=2013-10-23}}</ref><br />
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If the composite system is in this state, it is impossible to attribute to either system or system a definite pure state. Another way to say this is that while the von Neumann entropy of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry. The above example is one of four Bell states, which are (maximally) entangled pure states (pure states of the space, but which cannot be separated into pure states of each and ).<br />
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如果复合系统处于这种状态,就不可能把某个系统或某个系统归于一个确定的纯状态。另一种说法是,虽然整个状态的冯诺依曼熵为零(就像任何纯状态一样),但子系统的熵大于零。从这个意义上说,系统是“纠缠”的。这对干涉测量法有具体的经验影响。上面的例子是四个贝尔态中的一个,它们是(最大)纠缠纯态(空间的纯态,但不能分为每个和的纯态)。<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted{{by whom|date=August 2020}} to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts.<ref name="medium.com"/><br />
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Now suppose Alice is an observer for system , and Bob is an observer for system . If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of , there are two possible outcomes, occurring with equal probability:<br />
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现在假设 Alice 是系统的观察者,而 Bob 是系统的观察者。如果在上面给出的纠缠态中,爱丽丝在[ | 0 rangle,| 1 rangle ] </math 本征基中进行测量,有两种可能的结果,发生的概率相等:<br />
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=== Source for the arrow of time ===<br />
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Physicist [[Seth Lloyd]] says that [[quantum uncertainty]] gives rise to entanglement, the putative source of the [[arrow of time]]. According to Lloyd; "The arrow of time is an arrow of increasing correlations."<ref>{{Cite journal|url=https://www.wired.com/2014/04/quantum-theory-flow-time/|title=New Quantum Theory Could Explain the Flow of Time|journal=Wired|accessdate=13 October 2014|date=2014-04-25|last1=Wolchover|first1=Natalie}}</ref> The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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Alice 测量0,系统的状态崩溃为 < math > scriptstyle | 0 rangle _ a | 1 rangle _ b </math > 。<br />
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Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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Alice 测量1,系统的状态崩溃为 < math > scriptstyle | 1 rangle _ a | 0 rangle _ b </math > 。<br />
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=== Emergent gravity ===<br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system has been altered by Alice performing a local measurement on system . This remains true even if the systems and are spatially separated. This is the foundation of the EPR paradox.<br />
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如果前者发生,那么 Bob 在相同基础上执行的任何后续测量都将返回1。如果出现后一种情况,(Alice 度量1) ,那么 Bob 的度量将确定返回0。因此,Alice 对系统进行了本地测量,从而对系统进行了更改。即使系统和空间上是分开的,这也是正确的。这就是 EPR 悖论的基础。<br />
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Based on [[AdS/CFT correspondence]], [[Mark Van Raamsdonk]] suggested that [[spacetime]] arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time.<ref>{{Cite journal|last=Van Raamsdonk|first=Mark|date=2010-06-19|title=Building up spacetime with quantum entanglement|journal=General Relativity and Gravitation|language=en|volume=42|issue=10|pages=2323–2329|doi=10.1007/s10714-010-1034-0|issn=0001-7701|arxiv=1005.3035|bibcode=2010GReGr..42.2323V}}</ref> [[Induced gravity]] can emerge from the entanglement first law.<ref>{{Cite journal|last1=Lee|first1=Jae-Weon|last2=Kim|first2=Hyeong-Chan|last3=Lee|first3=Jungjai|date=2013|title=Gravity from quantum information|journal=Journal of the Korean Physical Society|language=en|volume=63|issue=5|pages=1094–1098|doi=10.3938/jkps.63.1094|issn=0374-4884|arxiv=1001.5445|bibcode=2013JKPS...63.1094L|s2cid=118494859}}</ref><ref>{{cite arxiv|last1=Swingle|first1=Brian|last2=Van Raamsdonk|first2=Mark|date=2014-05-12|title=Universality of Gravity from Entanglement|eprint=1405.2933 |class=hep-th}}</ref><br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem.<br />
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爱丽丝的测量结果是随机的。Alice 不能决定将组合系统折叠到哪个状态,因此不能通过作用于她的系统将信息传递给 Bob。因此,在这个特定的方案中,因果关系被保留了下来。关于一般的论点,请参阅不交流定理。<br />
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== Non-locality and entanglement ==<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations.<ref name="Brunner-RMP2014">{{cite journal |title=Bell nonlocality |author1=Nicolas Brunner |author2=Daniel Cavalcanti |author3=Stefano Pironio |author4=Valerio Scarani |author5=Stephanie Wehner |journal=Rev. Mod. Phys. |volume=86 |issue=2 |pages=419–478 |date=2014 |doi=10.1103/RevModPhys.86.419 |arxiv=1303.2849|bibcode=2014RvMP...86..419B |s2cid=119194006 }}</ref> A well-known example is the [[Werner state]]s that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables.<ref name=werner1989>{{cite journal | last = Werner| first = R.F. | title = Quantum States with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model | journal = [[Physical Review A]] | volume = 40| pages = 4277–4281 | year = 1989 |doi=10.1103/PhysRevA.40.4277 | pmid=9902666 | issue=8|bibcode = 1989PhRvA..40.4277W }}</ref> Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<ref>{{cite journal|author=R. Augusiak, M. Demianowicz, J. Tura and A. Acín |title=Entanglement and Nonlocality are Inequivalent for Any Number of Parties |journal=Phys. Rev. Lett. |volume=115 |issue=3 |pages=030404 |year=2015 |arxiv=1407.3114 |doi=10.1103/PhysRevLett.115.030404|pmid=26230773 |hdl=2117/78836 |bibcode=2015PhRvL.115c0404A |s2cid=29758483 }}</ref><br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all [[entanglement distillation|distillable]] states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<ref>{{cite journal |title=Disproving the Peres conjecture: Bell nonlocality from bipartite bound entanglement |authors=Tamas Vértesi, Nicolas Brunner|year=2014 |journal=Nature Communications |volume=5 |issue=5297|page=5297 |doi=10.1038/ncomms6297 |pmid=25370352|arxiv=1405.4502 |s2cid=5135148}}</ref><br />
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As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a density matrix, which is a positive-semidefinite matrix, or a trace class when the state space is infinite-dimensional, and has trace 1. Again, by the spectral theorem, such a matrix takes the general form:<br />
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如上所述,量子系统的状态是由希尔伯特空间中的单位向量给出的。更一般地说,如果一个人对系统的了解较少,那么他就称之为“集合” ,并用密度矩阵来描述它,密度矩阵是正半定矩阵,或者当状态空间是无限维且迹1时,用迹类来描述它。同样的,在谱定理,这样的矩阵采取了一般的形式:<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to [[quantum teleportation]] and to [[superdense coding]], whereas non-locality is defined according to experimental statistics and is much more involved with the [[Quantum foundations|foundations]] and [[interpretations of quantum mechanics]].<ref>In the literature "non-locality" is sometimes used to characterize concepts that differ from the non-existence of a local hidden variable model, e.g., whether states can be distinguished by local measurements and which can occur also for non-entangled states (see, e.g., {{cite journal |authors=Charles H. Bennett, David P. DiVincenzo, Christopher A. Fuchs, Tal Mor, Eric Rains, Peter W. Shor, John A. Smolin, and William K. Wootters |title=Quantum nonlocality without entanglement |journal=Phys. Rev. A |volume=59 |issue=2 |pages=1070–1091 |year=1999 |doi=10.1103/PhysRevA.59.1070 |arxiv= quant-ph/9804053|bibcode=1999PhRvA..59.1070B |s2cid=15282650 }}). This non-standard use of the term is not discussed here.</ref><br />
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<math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
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我不知道,我不知道,我不知道<br />
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== Quantum mechanical framework ==<br />
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where the w<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret as representing an ensemble where is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need density matrices to represent the state.<br />
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其中 w < sub > i </sub > 是正值概率(和为1) ,向量是单位向量,在无限维情况下,我们取这些状态的闭包为迹范数。我们可以解释为代表一个集合,其中集合的状态是 < math > | alpha _ i rangle </math > 。当一个混合状态的秩为1时,它就描述了一个纯系综。当量子系统的状态信息少于总量时,我们需要密度矩阵来表示状态。<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of [[quantum mechanics]], including familiarity with the formalism and theoretical framework developed in the articles: [[bra–ket notation]] and [[mathematical formulation of quantum mechanics]].<br />
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Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits electrons towards an observer. The electrons' Hilbert spaces are identical. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with spins aligned in the positive direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
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在实验上,可以实现如下的混合集成。考虑一个“黑盒子”装置,它向观察者喷射电子。电子的希尔伯特空间是相同的。该装置可能产生全部处于相同状态的电子; 在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以在不同的状态下产生电子。例如,它可以产生两个电子群: 一个是状态 < math > | mathbf { z } + rangle </math > 的正方向自旋,另一个是状态 < math > | mathbf { y }-rangle </math > 的负方向自旋。通常,这是一个混合集合,因为可以有任意数量的总体,每个总体对应不同的状态。<br />
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=== Pure states ===<br />
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Consider two arbitrary quantum systems {{mvar|A}} and {{mvar|B}}, with respective [[Hilbert space]]s {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}. The Hilbert space of the composite system is the [[tensor product]]<br />
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Following the definition above, for a bipartite composite system, mixed states are just density matrices on . That is, it has the general form<br />
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根据上面的定义,对于二部复合系统,混合态仅仅是上面的密度矩阵。也就是说,它有一般的形式<br />
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: <math> H_A \otimes H_B.</math><br />
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<math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
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[数学] rho = sum { i } w _ i 左[ sum _ { j } bar { c }{ ij }(| alpha _ { ij } rangle otimes | beta _ { ij } rangle)右]左[ sum _ k c _ { ik }(langle alpha _ ik } | otimes langle beta _ { ik } | 右]<br />
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</math><br />
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数学<br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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where the w<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
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其中 w < sub > i </sub > 是正值概率,< math > sum _ j | c _ { ij } | ^ 2 = 1 </math > ,向量是单位向量。这是自伴和正的,并且有迹1。<br />
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: <math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<br />
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从纯粹情形扩展可分性的定义,我们说混合状态是可分的,如果它可以写成<br />
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States of the composite system that can be represented in this form are called [[separable state]]s, or [[product state]]s.<br />
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<math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
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(数学) rho = sum i w i rho i ^ a times rho i ^ b,(数学)<br />
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Not all states are separable states (and thus product states). Fix a [[basis (linear algebra)|basis]] <math>\scriptstyle \{|i \rangle_A\}</math> for {{mvar|H<sub>A</sub>}} and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for {{mvar|H<sub>B</sub>}}. The most general state in {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} is of the form<br />
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where the are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems and respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
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其中的正值概率和 rho _ i ^ a </math > 的和 rho _ i ^ b </math > 的本身是子系统和子系统上的混合状态(密度算符)。换句话说,如果一个状态是不相关状态或乘积状态上的概率分布,则该状态是可分的。通过将密度矩阵写成纯系综和并进行扩展,我们可以假定,不失一般性和数学本身就是纯系综。如果一个状态不可分离,则称其为纠缠态。<br />
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: <math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be NP-hard. For the and cases, a necessary and sufficient criterion for separability is given by the famous Positive Partial Transpose (PPT) condition.<br />
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一般来说,要判断一个混合态是否是纠缠态是很困难的。一般的二部格被证明是 np 困难的。对于和种情形,利用著名的正偏转子(PPT)条件给出了可分性的一个充要条件。<br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of {{mvar|H<sub>A</sub>}} and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of {{mvar|H<sub>B</sub>}}, the following is an entangled state:<br />
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The idea of a reduced density matrix was introduced by Paul Dirac in 1930. Consider as above systems and each with a Hilbert space . Let the state of the composite system be<br />
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约化密度矩阵的概念是由保罗 · 狄拉克在1930年提出的。考虑以上系统,每个系统都有一个希尔伯特空间。设复合系统的状态为<br />
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: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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<math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
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[数学] | Psi 在 h _ a 和 h _ b 之间。数学<br />
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If the composite system is in this state, it is impossible to attribute to either system {{mvar|A}} or system {{mvar|B}} a definite [[pure state]]. Another way to say this is that while the [[von Neumann entropy]] of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry.<ref name="JaegerEtAl95">{{cite journal |author=Jaeger G, Shimony A, Vaidman L |title=Two Interferometric Complementarities |journal=Phys. Rev. |volume=51 |issue=1 |pages=54–67 |year=1995 |doi=10.1103/PhysRevA.51.54|pmid=9911555 |bibcode = 1995PhRvA..51...54J |last2=Shimony |last3=Vaidman }}</ref> The above example is one of four [[Bell states]], which are (maximally) entangled pure states (pure states of the {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} space, but which cannot be separated into pure states of each {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}).<br />
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As indicated above, in general there is no way to associate a pure state to the component system . However, it still is possible to associate a density matrix. Let<br />
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如上所述,通常没有办法将纯状态关联到组件系统。然而,仍然有可能将密度矩阵联系起来。让<br />
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Now suppose Alice is an observer for system {{mvar|A}}, and Bob is an observer for system {{mvar|B}}. If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of {{mvar|A}}, there are two possible outcomes, occurring with equal probability:<ref name=nielchuang>{{cite book| last = Nielsen | first = Michael A. |author2=Chuang, Isaac L. | year = 2000 | title = Quantum Computation and Quantum Information | publisher = [[Cambridge University Press]] | pages = 112–113| isbn = 978-0-521-63503-5}}</ref><br />
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<math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
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我不知道,我不知道,我不知道。<br />
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# Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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which is the projection operator onto this state. The state of is the partial trace of over the basis of system :<br />
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也就是这个状态的投影操作符。状态是系统基础上的部分轨迹:<br />
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# Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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<math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
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(| Psi rangle langle Psi | right) | j rangle b = hbox { Tr } _ b; rho _ t. </math > <br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system {{mvar|B}} has been altered by Alice performing a local measurement on system {{mvar|A}}. This remains true even if the systems {{mvar|A}} and {{mvar|B}} are spatially separated. This is the foundation of the [[EPR paradox]].<br />
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is sometimes called the reduced density matrix of on subsystem . Colloquially, we "trace out" system to obtain the reduced density matrix on .<br />
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有时被称为子系统的约化密度矩阵。通俗地说,我们“追踪”系统,以获得约化密度矩阵。<br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see [[no-communication theorem]].<br />
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For example, the reduced density matrix of for the entangled state<br />
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例如,纠缠态的约化密度矩阵<br />
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=== Ensembles ===<br />
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As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a [[density matrix]], which is a [[positive-semidefinite matrix]], or a [[trace class]] when the state space is infinite-dimensional, and has trace 1. Again, by the [[spectral theorem]], such a matrix takes the general form:<br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right) ,</math > <br />
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: <math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
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discussed above is<br />
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以上所讨论的是<br />
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where the ''w''<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors {{mvar| α<sub>i</sub>}} are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret {{mvar|ρ}} as representing an ensemble where {{mvar|w<sub>i</sub>}} is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need [[#Reduced density matrices|density matrices]] to represent the state.<br />
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<math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
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左(| 0 rangle 0 | a + | 1 rangle 1 | a right) </math > <br />
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Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits [[electron]]s towards an observer. The electrons' Hilbert spaces are [[identical particles|identical]]. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with [[spin (physics)|spins]] aligned in the positive {{math|'''z'''}} direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative {{math|'''y'''}} direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
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This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
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这表明,正如预期的那样,一个纠缠纯系综的约化密度矩阵是一个混合系综。同样不足为奇的是,上面讨论的纯乘积态的密度矩阵<br />
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Following the definition above, for a bipartite composite system, mixed states are just density matrices on {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}}. That is, it has the general form<br />
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<math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
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我不知道,但是我知道,我知道。<br />
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: <math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
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In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
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一般情况下,二体纯态 ρ 纠缠当且仅当其约化态是混合态而不是纯态。<br />
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</math><br />
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where the ''w''<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
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Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional AKLT spin chain: the ground state can be divided into a block and an environment. The reduced density matrix of the block is proportional to a projector to a degenerate ground state of another Hamiltonian.<br />
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在不同的基态自旋链中显式计算了约化密度矩阵。一维 AKLT 自旋链就是一个例子: 基态可以分为一个区块和一个环境。块的约化密度矩阵与另一个哈密顿量的简并基态成正比。<br />
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Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<ref name=Laloe>{{citation|last=Laloe|first=Franck|year=2001|title=Do We Really Understand Quantum Mechanics|journal=American Journal of Physics |volume=69 |issue=6|pages=655–701 |arxiv=quant-ph/0209123 |bibcode=2001AmJPh..69..655L |doi=10.1119/1.1356698}}</ref>{{rp|131–132}}<br />
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The reduced density matrix also was evaluated for XY spin chains, where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence in this case.<br />
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并对 XY 自旋链的全秩约化密度矩阵进行了计算。证明了在热力学极限中,大块自旋的约化密度矩阵的谱在这种情况下是一个精确的几何序列。<br />
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: <math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
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In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary quantum operations can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called LOCC (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<br />
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在量子信息理论中,纠缠态被认为是一种“资源” ,即制造成本高昂的物质,并且可以实现有价值的转换。这种观点最为明显的背景是“遥远的实验室” ,即两个标记为“ a”和“ b”的量子系统,其中每个系统都可以执行任意的量子操作,但它们之间不存在量子力学相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为 LOCC 的操作(局部操作和经典通信)。这些操作不允许在系统 a 和系统 b 之间产生纠缠态。但是如果给 a 和 b 提供了纠缠态,那么这些纠缠态和 LOCC 操作一起可以产生更大类的变换。例如,a 的一个量子比特和 b 的一个量子比特之间的相互作用可以通过首先将 a 的量子比特传送到 b,然后让 b 的量子比特和 b 的量子比特相互作用(这现在是一个 LOCC 操作,因为两个量子比特都在 b 的实验室里) ,然后再传送量子比特回到 a。两个量子比特的最大纠缠态在这个过程中被用完。因此,纠缠态是一种资源,它能够在只有 LOCC 可用的情况下实现量子相互作用(或量子通道) ,但是在这个过程中会被消耗掉。在其他应用中,纠缠态可以被看作是一种资源,例如,私人通信或者区分量子态。<br />
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where the {{mvar|w<sub>i</sub>}} are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems {{mvar|A}} and {{mvar|B}} respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
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In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be [[NP-hard]].<ref>{{Cite book |author=Gurvits L |title=Proceedings of the thirty-fifth ACM symposium on Theory of computing - STOC '03 |chapter=Classical deterministic complexity of Edmonds' Problem and quantum entanglement |journal=Proceedings of the Thirty-fifth Annual ACM Symposium on Theory of Computing |year=2003 |doi=10.1145/780542.780545 |page=10 |isbn=978-1-58113-674-6|arxiv=quant-ph/0303055 |s2cid=5745067 }}</ref> For the {{math|2 × 2}} and {{math|2 × 3}} cases, a necessary and sufficient criterion for separability is given by the famous [[Peres-Horodecki criterion|Positive Partial Transpose (PPT)]] condition.<ref>{{cite journal |author=Horodecki M, Horodecki P, Horodecki R |title=Separability of mixed states: necessary and sufficient conditions |journal=Physics Letters A |volume=223 |issue=1 |page=210 |year=1996 |doi=10.1016/S0375-9601(96)00706-2 |bibcode=1996PhLA..223....1H|arxiv = quant-ph/9605038 |last2=Horodecki |last3=Horodecki |citeseerx=10.1.1.252.496 |s2cid=10580997 }}</ref><br />
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=== Reduced density matrices ===<br />
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In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
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在这一节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的度量。<br />
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The idea of a reduced density matrix was introduced by [[Paul Dirac]] in 1930.<ref>{{cite journal|doi=10.1017/S0305004100016108|title=Note on Exchange Phenomena in the Thomas Atom|year=2008|last1=Dirac|first1=P. A. M.|journal=Mathematical Proceedings of the Cambridge Philosophical Society| volume=26| issue=3|page=376|bibcode=1930PCPS...26..376D|url=https://www.cambridge.org/core/services/aop-cambridge-core/content/view/6C5FF7297CD96F49A8B8E9E3EA50E412/S0305004100016108a.pdf/div-class-title-note-on-exchange-phenomena-in-the-thomas-atom-div.pdf}}</ref> Consider as above systems {{mvar|A}} and {{mvar|B}} each with a Hilbert space {{mvar|H<sub>A</sub>, H<sub>B</sub>}}. Let the state of the composite system be<br />
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: <math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
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The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.<br />
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二分子2能级纯态的冯纽曼熵与本征值的图。当本征值为5时,冯纽曼熵处于最大值,相当于最大纠缠度。<br />
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In classical information theory , the Shannon entropy, is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<br />
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在经典的信息论中,香农熵,是与概率分布相关联的,如下:<br />
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As indicated above, in general there is no way to associate a pure state to the component system {{mvar|A}}. However, it still is possible to associate a density matrix. Let<br />
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<math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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[ math ] h (p _ 1,cdots,p _ n) =-sum _ i p _ i log _ 2 p _ i. [ math ]<br />
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: <math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
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Since a mixed state is a probability distribution over an ensemble, this leads naturally to the definition of the von Neumann entropy:<br />
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由于混合状态是一个概率分布超过一个总体,这自然导致了冯纽曼熵的定义:<br />
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which is the [[projection operator]] onto this state. The state of {{mvar|A}} is the [[partial trace]] of {{mvar|ρ<sub>T</sub>}} over the basis of system {{mvar|B}}:<br />
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<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
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(rho) =-hbox { Tr } left (rho log _ 2{ rho } right) <br />
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: <math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
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In general, one uses the Borel functional calculus to calculate a non-polynomial function such as . If the nonnegative operator acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
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一般来说,人们使用 Borel 函数演算来计算一个非多项式函数,如。如果非负算子作用于有限维希尔伯特空间,并且具有本征值 < math > lambda _ 1,那么 cdots,lambda _ n </math > ,结果只不过是具有相同本征向量的算子,但本征值 < math > log _ 2(lambda _ 1) ,点,log _ 2(lambda _ n) </math > 。那么香农熵就是:<br />
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{{mvar|ρ<sub>A</sub>}} is sometimes called the reduced density matrix of {{mvar|ρ}} on subsystem {{mvar|A}}. Colloquially, we "trace out" system {{mvar|B}} to obtain the reduced density matrix on {{mvar|A}}.<br />
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<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
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(rho) =-hbox { Tr } left (rho log 2{ rho } right) =-sum _ i lambda _ i log _ 2 lambda _ i </math > .<br />
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For example, the reduced density matrix of {{mvar|A}} for the entangled state<br />
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Since an event of probability 0 should not contribute to the entropy, and given that<br />
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因为一个概率为0的事件不应该对熵有贡献,并且假设<br />
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: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
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<math> \lim_{p \to 0} p \log p = 0,</math><br />
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[ math > lim _ { p to 0} p log p = 0,</math > <br />
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discussed above is<br />
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the convention 0}} is adopted. This extends to the infinite-dimensional case as well: if has spectral resolution<br />
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约定0}被采用。这也延伸到无限维情况: 如果有光谱分辨率<br />
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: <math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
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<math> \rho = \int \lambda d P_{\lambda},</math><br />
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数学,数学,数学<br />
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This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of {{mvar|A}} for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
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assume the same convention when calculating<br />
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在计算时采用相同的约定<br />
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: <math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
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<math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
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[数学] rho log 2 rho = int lambda log 2 lambda d { lambda }<br />
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In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
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As in statistical mechanics, the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is (which can be shown to be the maximum entropy for mixed states).<br />
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就像统计力学一样,系统的不确定性(微观状态的数量)越多,熵就越大。例如,任何纯态的熵都为零,这并不奇怪,因为处于纯态的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个的熵都是(混合态的最大熵)。<br />
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=== Two applications that use them ===<br />
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Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional [[AKLT Model|AKLT spin chain]]:<ref name="Fan2004">{{cite journal | doi = 10.1103/PhysRevLett.93.227203 | title = Entanglement in a Valence-Bond Solid State | journal = Physical Review Letters | year = 2004 | first = H | last = Fan | page = 227203 |author2=Korepin V |author3=Roychowdhury V | volume = 93 | issue = 22 | pmid = 15601113 |arxiv=quant-ph/0406067 | bibcode=2004PhRvL..93v7203F| s2cid = 28587190 }}</ref> the ground state can be divided into a block and an environment. The reduced density matrix of the block is [[Proportionality (mathematics)|proportional]] to a projector to a degenerate ground state of another Hamiltonian.<br />
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Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist. If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
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熵提供了一个可以用来量化纠缠的工具,尽管还存在其他的纠缠度量方法。如果整个系统是纯系统,则可以用一个子系统的熵来衡量其与其他子系统的纠缠程度。<br />
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The reduced density matrix also was evaluated for [[Heisenberg model (quantum)|XY spin chains]], where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence<ref>{{cite journal| doi=10.1007/s11128-010-0197-7|arxiv=1002.2931|title=Spectrum of the density matrix of a large ''block of'' spins of the XY model in one dimension| year=2010|last1=Franchini|first1=F.|last2=Its|first2=A. R.|last3=Korepin|first3=V. E.|last4=Takhtajan|first4=L. A.|journal=Quantum Information Processing|volume=10|issue=3|pages=325–341|s2cid=6683370}}</ref> in this case.<br />
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For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
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对于两体纯态,减少态的冯纽曼熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的特定公理的态家族中唯一的函数。<br />
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=== Entanglement as a resource ===<br />
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In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary [[quantum operation]]s can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called [[LOCC]] (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<ref name="horodecki2007" /><br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/n,...,1/n}. Therefore, a bipartite pure state is said to be a maximally entangled state if the reduced state of is the diagonal matrix<br />
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一个经典的结果是,香农熵在均匀概率分布{1/n,... ,1/n }处达到最大值。因此,如果二分纯态的约化态是对角矩阵,则称二分纯态为最大纠缠态<br />
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=== Classification of entanglement ===<br />
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<math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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< math > begin { bmatrix } frac {1}{ n } & & ddots & frac {1}{ n } end { bmatrix } . </math > <br />
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Not all quantum states are equally valuable as a resource. To quantify this value, different [[Quantum entanglement#Entanglement measures|entanglement measures]] (see below) can be used, that assign a numerical value to each quantum state. However, it is often interesting to settle for a coarser way to compare quantum states. This gives rise to different classification schemes. Most entanglement classes are defined based on whether states can be converted to other states using LOCC or a subclass of these operations. The smaller the set of allowed operations, the finer the classification. Important examples are:<br />
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* If two states can be transformed into each other by a local unitary operation, they are said to be in the same ''LU class''. This is the finest of the usually considered classes. Two states in the same LU class have the same value for entanglement measures and the same value as a resource in the distant-labs setting. There is an infinite number of different LU classes (even in the simplest case of two qubits in a pure state).<ref name="GRB1998">>{{cite journal |author1=Grassl, M. |author2=Rötteler, M. |author3=Beth, T. |title=Computing local invariants of quantum-bit systems |journal=Phys. Rev. A |volume=58 |issue=3 |pages=1833–1839 |year=1998 |doi=10.1103/PhysRevA.58.1833 |arxiv=quant-ph/9712040|bibcode=1998PhRvA..58.1833G |s2cid=15892529 }}</ref><ref name="Kraus2010">{{cite journal |author=B. Kraus |authorlink=Barbara Kraus|title=Local unitary equivalence of multipartite pure states |journal=Phys. Rev. Lett. |volume=104 |issue=2 |page=020504 |year=2010 |arxiv=0909.5152 |doi=10.1103/PhysRevLett.104.020504|pmid=20366579 |bibcode=2010PhRvL.104b0504K|s2cid=29984499}}</ref><br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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对于混合态,简化冯纽曼熵并不是唯一合理的纠缠度量。<br />
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* If two states can be transformed into each other by local operations including measurements with probability larger than 0, they are said to be in the same 'SLOCC class' ("stochastic LOCC"). Qualitatively, two states <math>\rho_1</math> and <math>\rho_2</math> in the same SLOCC class are equally powerful (since I can transform one into the other and then do whatever it allows me to do), but since the transformations <math>\rho_1\to\rho_2</math> and <math>\rho_2\to\rho_1</math> may succeed with different probability, they are no longer equally valuable. E.g., for two pure qubits there are only two SLOCC classes: the entangled states (which contains both the (maximally entangled) Bell states and weakly entangled states like <math>|00\rangle+0.01|11\rangle</math>) and the separable ones (i.e., product states like <math>|00\rangle</math>).<ref>{{cite journal |author=M. A. Nielsen |title=Conditions for a Class of Entanglement Transformations |journal=Phys. Rev. Lett. |volume=83 |issue=2 |page=436 |year=1999 |doi=10.1103/PhysRevLett.83.436 |arxiv=quant-ph/9811053|bibcode=1999PhRvL..83..436N |s2cid=17928003 }}</ref><ref name="GoWa2010">{{cite journal |authors=Gour, G. & Wallach, N. R. |title=Classification of Multipartite Entanglement of All Finite Dimensionality |journal=Phys. Rev. Lett. |volume=111 |issue=6 |page=060502 |year=2013 |doi=10.1103/PhysRevLett.111.060502 |pmid=23971544 |arxiv=1304.7259|bibcode=2013PhRvL.111f0502G |s2cid=1570745 }}</ref><br />
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* Instead of considering transformations of single copies of a state (like <math>\rho_1\to\rho_2</math>) one can define classes based on the possibility of multi-copy transformations. E.g., there are examples when <math>\rho_1\to\rho_2</math> is impossible by LOCC, but <math>\rho_1\otimes\rho_1\to\rho_2</math> is possible. A very important (and very coarse) classification is based on the property whether it is possible to transform an arbitrarily large number of copies of a state <math>\rho</math> into at least one pure entangled state. States that have this property are called [[Entanglement distillation|distillable]]. These states are the most useful quantum states since, given enough of them, they can be transformed (with local operations) into any entangled state and hence allow for all possible uses. It came initially as a surprise that not all entangled states are distillable, those that are not are called '[[Bound entanglement|bound entangled]]'.<ref name="HHH97">{{cite journal |author1=Horodecki, M. |author2=Horodecki, P. |author3=Horodecki, R. |title=Mixed-state entanglement and distillation: Is there a ''bound'' entanglement in nature? |journal=Phys. Rev. Lett. |volume=80 |issue=1998 |pages=5239–5242 |year=1998 |arxiv=quant-ph/9801069|doi=10.1103/PhysRevLett.80.5239 |bibcode=1998PhRvL..80.5239H |s2cid=111379972 }}</ref><ref name="horodecki2007" /><br />
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As an aside, the information-theoretic definition is closely related to entropy in the sense of statistical mechanics (comparing the two definitions in the present context, it is customary to set the Boltzmann constant 1}}). For example, by properties of the Borel functional calculus, we see that for any unitary operator ,<br />
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顺便说一句,信息论的定义与统计力学意义上的熵密切相关(比较在当前语境下的两个定义,通常设置波兹曼常数1})。例如,通过 Borel 泛函微积分的性质,我们可以看到,对于任何幺正算符,<br />
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A different entanglement classification is based on what the quantum correlations present in a state allow A and B to do: one distinguishes three subsets of entangled states: (1) the ''[[Quantum nonlocality|non-local]] states'', which produce correlations that cannot be explained by a local hidden variable model and thus violate a Bell inequality, (2) the ''[[Quantum steering|steerable]] states'' that contain sufficient correlations for A to modify ("steer") by local measurements the conditional reduced state of B in such a way, that A can prove to B that the state they possess is indeed entangled, and finally (3) those entangled states that are neither non-local nor steerable. All three sets are non-empty.<ref name="WJD2007">{{cite journal |title=Steering, Entanglement, Nonlocality, and the Einstein-Podolsky-Rosen Paradox |authors=H. M. Wiseman, S. J. Jones, and A. C. Doherty |journal=Phys. Rev. Lett. |volume=98 |issue=14 |page=140402 |year=2007 |doi=10.1103/PhysRevLett.98.140402 |pmid=17501251 |arxiv=quant-ph/0612147|bibcode=2007PhRvL..98n0402W |s2cid=30078867 }}</ref><br />
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<math>S(\rho) = S \left (U \rho U^* \right).</math><br />
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s (rho) = s left (u rho u ^ * right) . </math > <br />
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=== Entropy ===<br />
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Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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事实上,如果没有这个属性,冯纽曼熵就不会有明确的定义。<br />
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In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
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In particular, could be the time evolution operator of the system, i.e.,<br />
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特别是,可以是系统的时间演化算子,即,<br />
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==== Definition ====<br />
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[[File:Von Neumann entropy for bipartite system plot.svg|right|thumb|200px|The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.]]<br />
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<math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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[ math ] u (t) = exp left (frac {-i h t }{ hbar } right) ,[ math ]<br />
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In classical [[information theory]] {{mvar|H}}, the [[Shannon entropy]], is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<ref name="SE">{{cite web |url=http://authors.library.caltech.edu/5516/1/CERpra97b.pdf#page=10 |title=Information-theoretic interpretation of quantum error-correcting codes |first1=Nicolas J. |last1=Cerf |first2=Richard |last2=Cleve }}</ref><br />
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where is the Hamiltonian of the system. Here the entropy is unchanged.<br />
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这个系统的哈密顿量在哪里。这里熵不变。<br />
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: <math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the arrow of time towards thermodynamic equilibrium is simply the growing spread of quantum entanglement.<br />
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一个过程的可逆性与由此产生的熵变有关,也就是说,一个过程是可逆的,当且仅当它使系统的熵不变。因此,时间之箭向热力学平衡的前进只不过是量子纠缠的蔓延。<br />
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Since a mixed state {{mvar|ρ}} is a probability distribution over an ensemble, this leads naturally to the definition of the [[von Neumann entropy]]:<br />
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This provides a connection between quantum information theory and thermodynamics.<br />
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这提供了量子信息理论和热力学之间的联系。<br />
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: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
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Rényi entropy also can be used as a measure of entanglement.<br />
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熵也可以用来度量纠缠。<br />
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In general, one uses the [[Borel functional calculus]] to calculate a non-polynomial function such as {{math|log<sub>2</sub>(''ρ'')}}. If the nonnegative operator {{mvar|ρ}} acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, {{math|log<sub>2</sub>(''ρ'')}} turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
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Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, entanglement entropy is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<br />
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量子纠缠度量了量子态(通常被视为双体)中纠缠的数量。如前所述,纠缠熵是纯态的标准量度(但不再是混合态的量度)。对于混合态,文献中有一些纠缠度量<br />
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: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
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Since an event of probability 0 should not contribute to the entropy, and given that<br />
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The Reeh-Schlieder theorem of quantum field theory is sometimes seen as an analogue of quantum entanglement.<br />
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量子场论的 Reeh-Schlieder 定理有时被看作是量子纠缠的类比。<br />
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:<math> \lim_{p \to 0} p \log p = 0,</math><br />
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the convention {{math|0 log(0) {{=}} 0}} is adopted. This extends to the infinite-dimensional case as well: if {{mvar|ρ}} has [[projection-valued measure|spectral resolution]]<br />
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Entanglement has many applications in quantum information theory. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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纠缠态在量子信息理论中有许多应用。在纠缠的帮助下,否则不可能完成的任务就可能实现。<br />
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: <math> \rho = \int \lambda d P_{\lambda},</math><br />
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Among the best-known applications of entanglement are superdense coding and quantum teleportation.<br />
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其中最著名的应用是超稠密编码和量子遥传纠缠。<br />
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assume the same convention when calculating<br />
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Most researchers believe that entanglement is necessary to realize quantum computing (although this is disputed by some).<br />
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大多数研究人员认为量子纠缠对于实现量子计算是必要的(尽管有些人对此有争议)。<br />
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: <math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
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Entanglement is used in some protocols of quantum cryptography. This is because the "shared noise" of entanglement makes for an excellent one-time pad. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.<br />
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纠缠被用于量子密码学的一些协议中。这是因为纠缠的“共享噪音”造就了绝佳的一次性衬垫。此外,由于测量纠缠对的任何一个成员都会破坏它们共享的纠缠,基于纠缠的量子密码学可以让发送方和接收方更容易地检测到拦截器的存在。<br />
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As in [[entropy|statistical mechanics]], the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is {{math|log(2)}} (which can be shown to be the maximum entropy for {{math|2 × 2}} mixed states).<br />
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In interferometry, entanglement is necessary for surpassing the standard quantum limit and achieving the Heisenberg limit.<br />
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在干涉术中,纠缠态对于超越标准量子极限和达到海森堡极限是必要的。<br />
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==== As a measure of entanglement ====<br />
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Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist.<ref name="arxiv.org">{{cite journal|author1=Plenio|title=An introduction to entanglement measures|year=2007|pages=1–51|volume=1|journal=Quant. Inf. Comp. |arxiv=quant-ph/0504163|bibcode=2005quant.ph..4163P|last2=Virmani}}</ref> If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
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There are several canonical entangled states that appear often in theory and experiments.<br />
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在理论和实验中经常会出现几种典型的纠缠态。<br />
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For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
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For two qubits, the Bell states are<br />
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对于两个量子比特,贝尔态是<br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/''n'',...,1/''n''}. Therefore, a bipartite pure state {{math|''ρ'' ∈ ''H''<sub>A</sub> ⊗ ''H''<sub>B</sub>}} is said to be a '''maximally entangled state''' if the reduced state{{clarify|reason=To which system, A or B, or perhaps both?|date=May 2015}} of {{mvar|ρ}} is the diagonal matrix<br />
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<math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
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< math > | Phi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 0 rangle _ b | 1 rangle _ a o times | 1 rangle _ b) </math > <br />
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<br />
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<math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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< math > | Psi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 1 rangle _ b pm | 1 rangle _ a o times | 0 rangle _ b) </math > .<br />
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: <math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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These four pure states are all maximally entangled (according to the entropy of entanglement) and form an orthonormal basis (linear algebra) of the Hilbert space of the two qubits. They play a fundamental role in Bell's theorem.<br />
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这四个纯态都是最大纠缠态(根据纠缠熵) ,并且形成了两个量子位的希尔伯特空间的标准正交基(线性代数)。它们在贝尔定理中起着基本的作用。<br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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For M>2 qubits, the GHZ state is<br />
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对于 m > 2量子位,GHZ 态是<br />
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As an aside, the information-theoretic definition is closely related to [[entropy (statistical views)|entropy]] in the sense of statistical mechanics{{Citation needed|date=January 2009}} (comparing the two definitions in the present context, it is customary to set the [[Boltzmann constant]] {{math|''k'' {{=}} 1}}). For example, by properties of the [[Borel functional calculus]], we see that for any [[unitary operator]] {{mvar|U}},<br />
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<math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
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< math > | mathrm { GHZ } rangle = frac { | 0 rangle ^ { otimes m } + | 1 rangle ^ { otimes m }{ sqrt {2} ,</math > <br />
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: <math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
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which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to qudits, i.e., systems of d rather than 2 dimensions.<br />
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它缩小到贝尔状态。传统的 GHZ 状态定义为 < math > m = 3 </math > 。GHZ 状态偶尔会扩展到 qudit,即 d 而不是2维系统。<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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Also for M>2 qubits, there are spin squeezed states. Spin squeezed states are a class of squeezed coherent states satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled. Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<br />
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对于 m > 2量子位,也存在自旋压缩态。自旋压缩态是一类对自旋测量不确定度满足一定限制的压缩相干态,它必然是纠缠态。自旋压缩态是利用量子纠缠增强精密测量的理想候选态。<br />
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In particular, {{mvar|U}} could be the time evolution operator of the system, i.e.,<br />
<br />
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For two bosonic modes, a NOON state is<br />
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对于两个玻色模态,NOON 状态是<br />
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: <math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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<math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
<br />
[数学] | psi _ text { NOON } rangle = frac { | n rangle _ a | 0 rangle _ b + | {0} rangle _ a | { n } rangle _ b }{ sqrt {2} ,,</math > <br />
<br />
where {{mvar|H}} is the [[Hamiltonian (quantum mechanics)|Hamiltonian]] of the system. Here the entropy is unchanged.<br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the N photons are in one mode" and "the N photons are in the other mode".<br />
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这就像贝尔态 < math > | Psi ^ + rangle </math > 除了基函数0和1已经被“ n 个光子处于一种模式”和“ n 个光子处于另一种模式”所取代。<br />
<br />
The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the [[arrow of time]] towards [[thermodynamic equilibrium]] is simply the growing spread of quantum entanglement.<ref>{{cite news |url=https://www.wired.com/2014/04/quantum-theory-flow-time/ |title=New Quantum Theory Could Explain the Flow of Time |last1=Wolchover |first1=Natalie |date=25 April 2014 |website=www.wired.com |publisher=Quanta Magazine |accessdate=27 April 2014}}</ref><br />
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This provides a connection between [[quantum information theory]] and [[thermodynamics]].<br />
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Finally, there also exist twin Fock states for bosonic modes, which can be created by feeding a Fock state into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<br />
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最后,还存在玻色子模式的双 Fock 态,它可以通过将 Fock 态输入到两个导致分束器的臂来产生。它们是 NOON 态的倍数之和,可以用来实现海森堡极限。<br />
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[[Rényi entropy]] also can be used as a measure of entanglement.<br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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对于适当选择的纠缠度量,Bell、 GHZ 和 NOON 态是最大纠缠态,而自旋压缩态和双 Fock 态只是部分纠缠。部分纠缠态通常更容易在实验上准备。<br />
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<br />
=== Entanglement measures ===<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, [[entropy of entanglement|entanglement entropy]] is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<ref name="arxiv.org" /> and no single one is standard.<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is spontaneous parametric down-conversion to generate a pair of photons entangled in polarisation. Other methods include the use of a fiber coupler to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a quantum dot, the use of the Hong–Ou–Mandel effect, etc., In the earliest tests of Bell's theorem, the entangled particles were generated using atomic cascades.<br />
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纠缠通常是由亚原子粒子间的直接相互作用产生的。这些相互作用可以有多种形式。最常用的方法之一是用自发参量下转换产生一对纠缠在偏振中的光子。其他方法包括使用光纤耦合器来限制和混合光子,量子点中双激子衰变级联发射的光子,Hong-Ou-Mandel 效应的使用等等。在贝尔定理最早的测试中,纠缠粒子是利用原子级联产生的。<br />
<br />
* Entanglement cost<br />
<br />
* [[entanglement distillation|Distillable entanglement]]<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of entanglement swapping. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<br />
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通过使用纠缠交换,也有可能在不直接相互作用的量子系统之间创造纠缠。如果它们的波函数在空间上仅仅重叠,至少是部分重叠,那么它们也可以相互纠缠全同粒子。<br />
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* Entanglement of formation<br />
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* [[quantum relative entropy|Relative entropy of entanglement]]<br />
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* [[Squashed entanglement]]<br />
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* [[Logarithmic negativity]]<br />
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A density matrix ρ is called separable if it can be written as a convex sum of product states, namely<br />
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密度矩阵 ρ 称为可分的,如果它可以写成乘积态的凸和,即<br />
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Most (but not all) of these entanglement measures reduce for pure states to entanglement entropy, and are difficult ([[NP-hard]]) to compute.<ref>{{cite journal|last1=Huang|first1=Yichen|title=Computing quantum discord is NP-complete|journal=New Journal of Physics|date=21 March 2014|volume=16|issue=3|pages=033027|doi=10.1088/1367-2630/16/3/033027|bibcode=2014NJPh...16c3027H|arxiv = 1305.5941 |s2cid=118556793}}</ref><br />
<br />
<br />
<br />
<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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显示方式{ rho = sum _ j p _ j rho _ j ^ {(a)}次 rho _ j ^ {(b)}} </math > <br />
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=== Quantum field theory ===<br />
<br />
The [[Reeh-Schlieder theorem]] of [[quantum field theory]] is sometimes seen as an analogue of quantum entanglement.<br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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概率为1 ge p _ j ge 0 </math > 。根据定义,如果一个态不可分离,它就是纠缠态。<br />
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== Applications ==<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple Peres–Horodecki criterion provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes NP-hard when generalized. Other separability criteria include (but not limited to) the range criterion, reduction criterion, and those based on uncertainty relations. See Ref. for a review of separability criteria in discrete variable systems.<br />
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对于2量子比特和2 × 2量子比特-量子特里特系统(分别为2 × 2和2 × 3) ,简单的 Peres-horowitz 准则为分离提供了一个必要和充分的判据,从而无意识地提供了检测纠缠的判据。然而,对于一般情形,该判据仅仅是可分性的必要条件,因为问题一经推广就变成了 np 难问题。其他可分性标准包括(但不限于)范围标准、归约标准和基于不确定关系的标准。参见参考文献。回顾了离散变量系统的可分性准则。<br />
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Entanglement has many applications in [[quantum information theory]]. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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A numerical approach to the problem is suggested by Jon Magne Leinaas, Jan Myrheim and Eirik Ovrum in their paper "Geometrical aspects of entanglement". Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in Peres-Horodecki criterion testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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Jon Magne Leinaas,Jan Myrheim 和 Eirik Ovrum 在他们的论文“纠缠的几何方面”中提出了一个数值方法来解决这个问题。莱纳斯等。提供一个数值方法,迭代精炼一个估计的可分离状态朝向要测试的目标状态,并检查目标状态是否确实能够到达。该算法的一个实现(包括内置的 peres-horowitz 标准测试)是[ StateSeparator http://phweb.technion.ac.il/~StateSeparator/] web-app。<br />
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Among the best-known applications of entanglement are [[superdense coding]] and [[quantum teleportation]].<ref>{{cite journal |last1=Bouwmeester |first1=Dik |last2=Pan |first2=Jian-Wei|last3=Mattle |first3=Klaus|last4=Eibl |first4=Manfred |last5=Weinfurter |first5=Harald|last6=Zeilinger |first6=Anton|year=1997 |title=Experimental Quantum Teleportation |journal=Nature |volume=390 |issue=6660 |pages=575–579 |name-list-style=amp |url=http://qudev.ethz.ch/content/courses/QSIT06/pdfs/Bouwmeester97.pdf |doi=10.1038/37539|bibcode = 1997Natur.390..575B |arxiv=1901.11004 |s2cid=4422887 }}</ref><br />
<br />
In continuous variable systems, the Peres-Horodecki criterion also applies. Specifically, Simon formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref. for a seemingly different but essentially equivalent approach). It was later found that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators or by using entropic measures.<br />
<br />
在连续变量系统中,Peres-Horodecki 准则也适用。具体地说,Simon 根据正则算符的二阶矩,制定了 Peres-Horodecki 准则的一个特定版本,并表明它对于 < math > 1 oplus1 </math >-mode Gaussian 状态是必要的和充分的。看似不同,但本质上等价的方法)。后来发现,Simon 的条件对于 < math > 1 oplus n </math >-mode Gaussian 状态也是必要和充分的,但是对于 < math > 2 oplus2 </math >-mode Gaussian 状态不再是充分的。Simon 条件可以通过考虑正则算子的高阶矩或者用熵测度来推广。<br />
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Most researchers believe that entanglement is necessary to realize [[quantum computer|quantum computing]] (although this is disputed by some).<ref name="jozsa02">{{cite journal|author1=Richard Jozsa|author2=Noah Linden|doi=10.1098/rspa.2002.1097|title=On the role of entanglement in quantum computational speed-up|year=2002|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=459|issue=2036|pages=2011–2032|arxiv=quant-ph/0201143|bibcode = 2003RSPSA.459.2011J |citeseerx=10.1.1.251.7637|s2cid=15470259}}</ref><br />
<br />
In 2016 China launched the world’s first quantum communications satellite. The $100m Quantum Experiments at Space Scale (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
<br />
2016年,中国发射了世界上第一颗量子通信卫星。耗资1亿美元的空间量子实验任务于2016年8月16日当地时间01:40从中国北方的酒泉卫星发射中心空间站发射升空。<br />
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Entanglement is used in some protocols of [[quantum cryptography]].<ref name="ekert91">{{cite journal |doi=10.1103/PhysRevLett.67.661 |title=Quantum cryptography based on Bell's theorem |year=1991 |last1=Ekert |first1=Artur K. |journal=Physical Review Letters |volume=67 |issue=6 |pages=661–663 |pmid=10044956|bibcode = 1991PhRvL..67..661E |s2cid=27683254 |url=http://pdfs.semanticscholar.org/f8dc/c3047eef8da135bca13b926b1e6cf50e7f3a.pdf }}</ref><ref name="horodecki10">{{cite arXiv |eprint=1006.0468|last1=Yin|first1=Juan|title=Contextuality offers device-independent security|last2=Cao|first2=Yuan|last3=Yong|first3=Hai-Lin|last4=Ren|first4=Ji-Gang|last5=Liang|first5=Hao|last6=Liao|first6=Sheng-Kai|last7=Zhou|first7=Fei|last8=Liu|first8=Chang|last9=Wu|first9=Yu-Ping|last10=Pan|first10=Ge-Sheng|last11=Zhang|first11=Qiang|last12=Peng|first12=Cheng-Zhi|last13=Pan|first13=Jian-Wei|class=quant-ph|year=2010}}</ref> This is because the "shared noise" of entanglement makes for an excellent [[one-time pad]]. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.{{citation needed|date=January 2018}}<br />
<br />
For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
<br />
在接下来的两年里,这艘以中国古代哲学家墨子命名的飞船将展示量子化的可行性<br />
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<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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地球和太空之间的通信,并在前所未有的距离上测试量子纠缠。<br />
<br />
In [[interferometry]], entanglement is necessary for surpassing the [[standard quantum limit]] and achieving the [[Heisenberg limit]].<ref>{{cite journal |last1=Pezze |first1=Luca |last2=Smerzi |first2=Augusto|year=2009 |title=Entanglement, Nonlinear Dynamics, and the Heisenberg Limit |journal=Phys. Rev. Lett. |volume=102 |issue=10 |pages=100401 |name-list-style=amp |doi=10.1103/PhysRevLett.102.100401 |pmid=19392092 |bibcode=2009PhRvL.102j0401P|arxiv = 0711.4840 |s2cid=13095638 }}</ref><br />
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<br />
<br />
In the June 16, 2017, issue of Science, Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<br />
<br />
在2017年6月16日的《科学》杂志上。在严格的爱因斯坦定域条件下,从墨丘利卫星到 Lijian、云南和 Delingha、 Quinhai 的基地的 CHSH 估值为2.37 ± 0.09,证明了双光子对的存在和对 Bell 不等式的违反,从而提高了数量级通过光纤实验的传输效率。<br />
<br />
=== Entangled states ===<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
<br />
<br />
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For two [[qubits]], the [[Bell state]]s are<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be calculated only by consideration of electron entanglement.<br />
<br />
多电子原子的电子壳层总是由纠缠电子组成。只有考虑到电子纠缠,才能计算出正确的电离能。<br />
<br />
<br />
<br />
: <math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
<br />
: <math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
<br />
<br />
<br />
It has been suggested that in the process of photosynthesis, entanglement is involved in the transfer of energy between light-harvesting complexes and photosynthetic reaction centers where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using femtosecond spectroscopy, the coherence of entanglement in the Fenna-Matthews-Olson complex was measured over hundreds of femtoseconds (a relatively long time in this regard) providing support to this theory.<br />
<br />
研究表明,在光合作用过程中,纠缠参与了捕光复合物与光合反应中心之间的能量传递,而光(能)是以化学能的形式获得的。没有这样一个过程,光转化为化学能的有效性就无从解释。利用飞秒光谱技术,我们测量了 Fenna-Matthews-Olson 复合体中纠缠态的相干性,时间长达数百飞秒,为这一理论提供了支持。<br />
<br />
These four pure states are all maximally entangled (according to the [[entropy of entanglement]]) and form an [[orthonormal]] [[basis (linear algebra)]] of the Hilbert space of the two qubits. They play a fundamental role in [[Bell's theorem]].<br />
<br />
However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<br />
<br />
然而,关键的后续研究对这些结果的解释提出了质疑,并将报告的电子量子相干特征赋予了发色团中的核动力学。<br />
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For M>2 qubits, the [[Greenberger–Horne–Zeilinger state|GHZ state]] is<br />
<br />
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In 2020 researchers reported the quantum entanglement between the motion of a millimetre-sized mechanical oscillator and a disparate distant spin system of a cloud of atoms.<br />
<br />
2020年,研究人员报告了一个毫米大小的机械振荡器的运动和一个原子云的不同距离的自旋系统之间的量子纠缠。<br />
<br />
: <math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
<br />
<br />
<br />
which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to [[qudit]]s, i.e., systems of ''d'' rather than 2 dimensions.<br />
<br />
In October 2018, physicists reported producing quantum entanglement using living organisms, particularly between photosynthetic molecules within living bacteria and quantized light.<br />
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2018年10月,物理学家报告说,他们利用活体生物制造量子纠缠,特别是利用活体细菌中的光合分子和量子化的光。<br />
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<br />
<br />
Also for M>2 qubits, there are [[Spin squeezing|spin squeezed states]].<ref>[http://qwiki.stanford.edu/index.php/Spin_Squeezed_State Database error – Qwiki] {{webarchive|url=https://web.archive.org/web/20120821011018/http://qwiki.stanford.edu/index.php/Spin_Squeezed_State |date=21 August 2012 }}</ref> Spin squeezed states are a class of [[squeezed coherent states]] satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled.<ref>{{cite journal | last1 = Kitagawa | first1 = Masahiro | last2 = Ueda | first2 = Masahito | year = 1993 | title = Squeezed Spin States | journal = Phys. Rev. A | volume = 47 | issue = 6| pages = 5138–5143 | doi=10.1103/physreva.47.5138| pmid = 9909547 |bibcode = 1993PhRvA..47.5138K }}</ref> Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<ref>{{cite journal | last1 = Wineland | first1 = D. J. | last2 = Bollinger | first2 = J. J. | last3 = Itano | first3 = W. M. | last4 = Moore | first4 = F. L. | last5 = Heinzen | first5 = D. J. | year = 1992| title = Spin squeezing and reduced quantum noise in spectroscopy | url = | journal = Phys. Rev. A | volume = 46| issue = 11| pages = R6797–R6800| doi = 10.1103/PhysRevA.46.R6797 | pmid = 9908086 |bibcode = 1992PhRvA..46.6797W }}</ref><br />
<br />
Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<br />
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生物体(绿色硫细菌)已被研究作为介质,在非相互作用的光模式之间创造量子纠缠,表明光和细菌模式之间的高度纠缠,甚至在某种程度上纠缠在细菌内部。<br />
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For two [[boson]]ic modes, a [[NOON state]] is<br />
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: <math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the ''N'' photons are in one mode" and "the ''N'' photons are in the other mode".<br />
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Finally, there also exist [[twin Fock states]] for bosonic modes, which can be created by feeding a [[Fock state]] into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.71.1355|pmid = 10055519|title = Interferometric detection of optical phase shifts at the Heisenberg limit|journal = Physical Review Letters|volume = 71|issue = 9|pages = 1355–1358|year = 1993|last1 = Holland|first1 = M. J|last2 = Burnett|first2 = K|bibcode = 1993PhRvL..71.1355H}}</ref><br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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=== Methods of creating entanglement ===<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is [[spontaneous parametric down-conversion]] to generate a pair of photons entangled in polarisation.<ref name="horodecki2007">{{cite journal |author=Horodecki R, Horodecki P, Horodecki M, Horodecki K |title=Quantum entanglement |journal=Rev. Mod. Phys. |arxiv=quant-ph/0702225 |doi =10.1103/RevModPhys.81.865 |year=2009|pages=865–942 |bibcode=2009RvMP...81..865H |volume=81 |issue=2|last2=Horodecki |last3=Horodecki |last4=Horodecki |s2cid=59577352 }}</ref> Other methods include the use of a [[fiber coupler]] to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a [[quantum dot]],<ref>{{Cite journal|last=Akopian|first=N.|date=2006|title=Entangled Photon Pairs from Semiconductor Quantum Dots|journal=Phys. Rev. Lett.|volume=96|issue=2|pages=130501|arxiv=quant-ph/0509060|bibcode=2006PhRvL..96b0501D|doi=10.1103/PhysRevLett.96.020501|pmid=16486553|s2cid=22040546}}</ref> the use of the [[Hong–Ou–Mandel effect]], etc., In the earliest tests of Bell's theorem, the entangled particles were generated using [[atomic cascade]]s.<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of [[Quantum teleportation#Entanglement swapping|entanglement swapping]]. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<ref>Rosario Lo Franco and Giuseppe Compagno, "Indistinguishability of Elementary Systems as a Resource for Quantum Information Processing", Phys. Rev. Lett. 120, 240403, 14 June 2018.</ref><br />
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=== Testing a system for entanglement ===<br />
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A density matrix ρ is called [[Separable state|separable]] if it can be written as a convex sum of product states, namely<br />
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<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple [[Peres–Horodecki criterion]] provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes [[NP-hard]] when generalized.<ref name="NP-hard1">Gurvits, L., Classical deterministic complexity of Edmonds' problem and quantum entanglement, in Proceedings of the 35th ACM Symposium on Theory of Computing, ACM Press, New York, 2003.</ref><ref name="NP-hard2">Sevag Gharibian, Strong NP-Hardness of the [[Quantum Separability Problem]], [[Quantum Information]] and what's known as [[Quantum Computing]], Vol. 10, No. 3&4, pp. 343–360, 2010. {{arXiv|0810.4507}}.</ref> Other separability criteria include (but not limited to) the [[range criterion]], [[reduction criterion]], and those based on uncertainty relations.<ref>{{cite journal |last1=Hofmann |first1=Holger F. |last2=Takeuchi |first2=Shigeki |title=Violation of local uncertainty relations as a signature of entanglement |journal=Physical Review A |date=22 September 2003 |volume=68 |issue=3 |page=032103 |doi=10.1103/PhysRevA.68.032103|arxiv=quant-ph/0212090 |bibcode=2003PhRvA..68c2103H |s2cid=54893300 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |title=Characterizing Entanglement via Uncertainty Relations |journal=Physical Review Letters |date=18 March 2004 |volume=92 |issue=11 |page=117903 |doi=10.1103/PhysRevLett.92.117903|pmid=15089173 |arxiv=quant-ph/0306194 |bibcode=2004PhRvL..92k7903G |s2cid=5696147 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |last2=Lewenstein |first2=Maciej |title=Entropic uncertainty relations and entanglement |journal=Physical Review A |date=24 August 2004 |volume=70 |issue=2 |page=022316 |doi=10.1103/PhysRevA.70.022316|bibcode=2004PhRvA..70b2316G |arxiv=quant-ph/0403219 |s2cid=118952931 }}</ref><ref>{{cite journal |last1=Huang |first1=Yichen |title=Entanglement criteria via concave-function uncertainty relations |journal=Physical Review A |date=29 July 2010 |volume=82 |issue=1 |page=012335 |doi=10.1103/PhysRevA.82.012335|bibcode=2010PhRvA..82a2335H }}</ref> See Ref.<ref>{{cite journal|last1=Gühne|first1=Otfried|last2=Tóth|first2=Géza|title=Entanglement detection|journal=Physics Reports|volume=474|issue=1–6|pages=1–75|doi=10.1016/j.physrep.2009.02.004|arxiv = 0811.2803 |bibcode = 2009PhR...474....1G |year=2009|s2cid=119288569}}</ref> for a review of separability criteria in discrete variable systems.<br />
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A numerical approach to the problem is suggested by [[Jon Magne Leinaas]], [[Jan Myrheim]] and [[Eirik Ovrum]] in their paper "Geometrical aspects of entanglement".<ref name="geom approach">{{cite journal | last1 = Leinaas| first1 = Jon Magne| last2 = Myrheim| first2 = Jan| last3 = Ovrum| first3 = Eirik| year = 2006 | title = Geometrical aspects of entanglement | url = | journal = Physical Review A | volume = 74 | issue = | page = 012313 | doi = 10.1103/PhysRevA.74.012313| arxiv = quant-ph/0605079| s2cid = 119443360}}</ref> Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in [[Peres-Horodecki criterion]] testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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In continuous variable systems, the [[Peres-Horodecki criterion]] also applies. Specifically, Simon <ref>{{cite journal|last1=Simon|first1=R.|title=Peres-Horodecki Separability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2726–2729|doi=10.1103/PhysRevLett.84.2726|arxiv = quant-ph/9909044 |bibcode = 2000PhRvL..84.2726S|pmid=11017310|year=2000|s2cid=11664720}}</ref> formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref.<ref>{{cite journal|last1=Duan|first1=Lu-Ming|last2=Giedke|first2=G.|last3=Cirac|first3=J. I.|last4=Zoller|first4=P.|title=Inseparability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2722–2725|doi=10.1103/PhysRevLett.84.2722|pmid=11017309|arxiv = quant-ph/9908056 |bibcode = 2000PhRvL..84.2722D |year=2000|s2cid=9948874}}</ref> for a seemingly different but essentially equivalent approach). It was later found <ref>{{cite journal|last1=Werner|first1=R. F.|last2=Wolf|first2=M. M.|title=Bound Entangled Gaussian States|journal=Physical Review Letters|volume=86|issue=16|pages=3658–3661|doi=10.1103/PhysRevLett.86.3658|pmid=11328047|arxiv = quant-ph/0009118 |bibcode = 2001PhRvL..86.3658W |year=2001|s2cid=20897950}}</ref> that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators <ref>{{cite journal|last1=Shchukin|first1=E.|last2=Vogel|first2=W.|title=Inseparability Criteria for Continuous Bipartite Quantum States|journal=Physical Review Letters|volume=95|issue=23|pages=230502|doi=10.1103/PhysRevLett.95.230502|pmid=16384285|arxiv = quant-ph/0508132 |bibcode = 2005PhRvL..95w0502S |year=2005|s2cid=28595936}}</ref><ref>{{cite journal|last1=Hillery|first1=Mark|last2=Zubairy|first2=M.Suhail|title=Entanglement Conditions for Two-Mode States|journal=Physical Review Letters|volume=96|issue=5|doi=10.1103/PhysRevLett.96.050503|arxiv = quant-ph/0507168 |bibcode = 2006PhRvL..96e0503H|pmid=16486912|page=050503|year=2006|s2cid=43756465}}</ref> or by using entropic measures.<ref>{{cite journal|last1=Walborn|first1=S.|last2=Taketani|first2=B.|last3=Salles|first3=A.|last4=Toscano|first4=F.|last5=de Matos Filho|first5=R.|title=Entropic Entanglement Criteria for Continuous Variables|journal=Physical Review Letters|volume=103|issue=16|doi=10.1103/PhysRevLett.103.160505|arxiv = 0909.0147 |bibcode = 2009PhRvL.103p0505W|pmid=19905682|page=160505|year=2009|s2cid=10523704}}</ref><ref>{{cite journal |last1=Yichen Huang |title=Entanglement Detection: Complexity and Shannon Entropic Criteria |journal=IEEE Transactions on Information Theory |date=October 2013 |volume=59 |issue=10 |pages=6774–6778 |doi=10.1109/TIT.2013.2257936|s2cid=7149863 }}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite.<ref>http://physicsworld.com/cws/article/news/2016/aug/16/china-launches-world-s-first-quantum-science-satellite</ref> The $100m [[Quantum Experiments at Space Scale]] (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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In the June 16, 2017, issue of ''Science'', Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<ref>{{cite journal | doi = 10.1126/science.aan3211 | volume=356 | title=Satellite-based entanglement distribution over 1200 kilometers | year=2017 | journal=Science | pages=1140–1144 | last1 = Yin | first1 = Juan | last2 = Cao | first2 = Yuan | last3 = Li | first3 = Yu-Huai | last4 = Liao | first4 = Sheng-Kai | last5 = Zhang | first5 = Liang | last6 = Ren | first6 = Ji-Gang | last7 = Cai | first7 = Wen-Qi | last8 = Liu | first8 = Wei-Yue | last9 = Li | first9 = Bo | last10 = Dai | first10 = Hui | last11 = Li | first11 = Guang-Bing | last12 = Lu | first12 = Qi-Ming | last13 = Gong | first13 = Yun-Hong | last14 = Xu | first14 = Yu | last15 = Li | first15 = Shuang-Lin | last16 = Li | first16 = Feng-Zhi | last17 = Yin | first17 = Ya-Yun | last18 = Jiang | first18 = Zi-Qing | last19 = Li | first19 = Ming | last20 = Jia | first20 = Jian-Jun | last21 = Ren | first21 = Ge | last22 = He | first22 = Dong | last23 = Zhou | first23 = Yi-Lin | last24 = Zhang | first24 = Xiao-Xiang | last25 = Wang | first25 = Na | last26 = Chang | first26 = Xiang | last27 = Zhu | first27 = Zhen-Cai | last28 = Liu | first28 = Nai-Le | last29 = Chen | first29 = Yu-Ao | last30 = Lu | first30 = Chao-Yang | last31 = Shu | first31 = Rong | last32 = Peng | first32 = Cheng-Zhi | last33 = Wang | first33 = Jian-Yu | last34 = Pan | first34 = Jian-Wei | issue=6343 | pmid = 28619937| doi-access = free }}</ref><ref>{{cite web | url=http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance | title=China's quantum satellite achieves 'spooky action' at record distance| date=2017-06-14}}</ref><br />
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== Naturally entangled systems ==<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be [[Configuration interaction|calculated]] only by consideration of electron entanglement.<ref>Frank Jensen: ''Introduction to Computational Chemistry.'' Wiley, 2007, {{ISBN|978-0-470-01187-4}}.</ref><br />
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== Photosynthesis ==<br />
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It has been suggested that in the process of [[photosynthesis]], entanglement is involved in the transfer of energy between [[light-harvesting complex]]es and [[photosynthetic reaction center]]s where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using [[femtosecond spectroscopy]], the coherence of entanglement in the [[Fenna-Matthews-Olson complex]] was measured over hundreds of [[femtosecond]]s (a relatively long time in this regard) providing support to this theory.<ref>Berkeley Lab Press Release: ''[http://newscenter.lbl.gov/feature-stories/2010/05/10/untangling-quantum-entanglement/ Untangling the Quantum Entanglement Behind Photosynthesis: Berkeley scientists shine new light on green plant secrets.]''</ref><ref>Mohan Sarovar, Akihito Ishizaki, Graham R. Fleming, K. Birgitta Whaley: ''Quantum entanglement in photosynthetic light harvesting complexes.'' {{arxiv|0905.3787}}</ref><br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<ref>{{cite journal | author = R. Tempelaar | author2 = T. L. C. Jansen | author3 = J. Knoester | title = Vibrational Beatings Conceal Evidence of Electronic Coherence in the FMO Light-Harvesting Complex | journal = J. Phys. Chem. B | volume = 118 | issue = 45 | pages = 12865–12872 | date = 2014 | doi=10.1021/jp510074q| pmid = 25321492 }}</ref><ref>{{cite journal | author = N. Christenson | author2 = H. F. Kauffmann | author3 = T. Pullerits | author4 = T. Mancal | title = Origin of Long-Lived Coherences in Light-Harvesting Complexes| journal = J. Phys. Chem. B | volume = 116 | issue = 25 | pages = 7449–7454 | date = 2012 | doi = 10.1021/jp304649c | pmid = 22642682 | pmc = 3789255 | bibcode = 2012arXiv1201.6325C | arxiv = 1201.6325 }}</ref><ref>{{cite journal | author = A. Kolli | author2 = E. J. O’Reilly | author3= G. D. Scholes | author4= A. Olaya-Castro | title = The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae| journal = J. Chem. Phys. | volume = 137 | issue = 17 | pages = 174109 | date = 2012 | doi=10.1063/1.4764100| pmid = 23145719 | bibcode = 2012JChPh.137q4109K | arxiv = 1203.5056 | s2cid = 20156821 }}</ref><ref>{{cite journal | author = V. Butkus | author2 = D. Zigmantas | author3= L. Valkunas | author4= D. Abramavicius | title = Vibrational vs. electronic coherences in 2D spectrum of molecular systems| journal = Chem. Phys. Lett. | volume = 545 | issue = 30 | pages = 40–43 | date = 2012 | doi=10.1016/j.cplett.2012.07.014| arxiv = 1201.2753 | bibcode = 2012CPL...545...40B | s2cid = 96663719 }}</ref><ref>{{cite journal | author = V. Tiwari | author2 = W. K. Peters | author3= D. M. Jonas | title = Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework | journal = Proc. Natl. Acad. Sci. USA | volume = 110 | issue = 4 | pages = 1203–1208 | date = 2013 | doi=10.1073/pnas.1211157110| pmid = 23267114 | pmc = 3557059 }}</ref><ref>{{cite journal | author = E. Thyrhaug | author2 = K. Zidek | author3 = J. Dostal | author4 = D. Bina | author5 = D. Zigmantas | title = Exciton Structure and Energy Transfer in the Fenna−Matthews− Olson Complex| journal = J. Phys. Chem. Lett. | volume = 7 | issue = 9 | pages = 1653–1660 | date = 2016 | doi=10.1021/acs.jpclett.6b00534| pmid = 27082631 }}</ref><ref>{{cite journal | author = Y. Fujihashi | author2 = G. R. Fleming | author3= A. Ishizaki | title = Impact of environmentally induced fluctuations on quantum mechanically mixed electronic and vibrational pigment states in photosynthetic energy transfer and 2D electronic spectra| journal = J. Chem. Phys. | volume = 142 | issue = 21 | pages = 212403 | date = 2015 | doi=10.1063/1.4914302| pmid = 26049423 | arxiv = 1505.05281 | bibcode = 2015JChPh.142u2403F | s2cid = 1082742 }}</ref><br />
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== Entanglement of macroscopic objects ==<br />
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In 2020 researchers reported the quantum entanglement between the [[Vibrations of a circular membrane|motion of a millimetre-sized mechanical oscillator]] and a disparate distant [[Spin (physics)|spin]] system of a cloud of atoms.<ref>{{cite news |title=Quantum entanglement realized between distant large objects |url=https://phys.org/news/2020-09-quantum-entanglement-distant-large.html |accessdate=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Thomas |first1=Rodrigo A. |last2=Parniak |first2=Michał |last3=Østfeldt |first3=Christoffer |last4=Møller |first4=Christoffer B. |last5=Bærentsen |first5=Christian |last6=Tsaturyan |first6=Yeghishe |last7=Schliesser |first7=Albert |last8=Appel |first8=Jürgen |last9=Zeuthen |first9=Emil |last10=Polzik |first10=Eugene S. |title=Entanglement between distant macroscopic mechanical and spin systems |journal=Nature Physics |date=21 September 2020 |pages=1–6 |doi=10.1038/s41567-020-1031-5 |url=https://www.nature.com/articles/s41567-020-1031-5 |accessdate=9 October 2020 |language=en |issn=1745-2481}}</ref><br />
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=== Entanglement of elements of living systems ===<br />
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In October 2018, physicists reported producing quantum entanglement using [[living organism]]s, particularly between photosynthetic molecules within living [[bacteria]] and [[Photon|quantized light]].<ref name="JPC-20181010">{{cite journal |last1=Marletto |first1=C. |last2=Coles |first2=D.M. |last3=Farrow |first3=T. |last4=Vedral |first4=V. |title=Entanglement between living bacteria and quantized light witnessed by Rabi splitting |date=10 October 2018 |journal=Journal of Physics: Communications |volume=2 |pages=101001 |number=10 |doi=10.1088/2399-6528/aae224 |bibcode=2018JPhCo...2j1001M |arxiv=1702.08075 |s2cid=119236759 }} [[File:CC-BY icon.svg|50px]] Text and images are available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref><ref name="SA-20181029">{{cite web |last=O'Callaghan |first=Jonathan |title="Schrödinger's Bacterium" Could Be a Quantum Biology Milestone – A recent experiment may have placed living organisms in a state of quantum entanglement |url=https://www.scientificamerican.com/article/schroedingers-bacterium-could-be-a-quantum-biology-milestone/ |date=29 October 2018 |work=[[Scientific American]] |accessdate=29 October 2018 }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<ref>{{cite journal | last1 = Krisnanda | first1 = T. | last2 = Marletto | first2 = C. | last3 = Vedral | first3 = V. | last4 = Paternostro | first4 = M. | last5 = Paterek | first5 = T. | year = 2018 | title = Probing quantum features of photosynthetic organisms | url = https://www.nature.com/articles/s41534-018-0110-2 | journal = NPJ Quantum Information | volume = 4 | issue = | page = 60 | doi = 10.1038/s41534-018-0110-2 | doi-access = free }}</ref><br />
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== See also ==<br />
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{{Portal|Physics}}<br />
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{{cols|colwidth=21em}}<br />
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* [[Quantum gate#Controlled gates|CNOT gate]]<br />
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* [[Bound entanglement]]<br />
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* [[Concurrence (quantum computing)]]<br />
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* [[Einstein's thought experiments]]<br />
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* [[Entanglement distillation]]<br />
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* [[Entanglement witness]]<br />
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* [[Faster-than-light communication]]<br />
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* [[Ghirardi–Rimini–Weber theory]]<br />
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* [[Multipartite entanglement]]<br />
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* [[Normally distributed and uncorrelated does not imply independent]]<br />
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* [[Observer effect (physics)]]<br />
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* [[Quantum coherence]]<br />
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* [[Quantum discord]]<br />
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* [[Quantum phase transition]]<br />
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* [[Quantum computing]]<br />
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* [[Quantum network]]<br />
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Category:Quantum information science<br />
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类别: 量子信息科学<br />
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* [[Quantum pseudo-telepathy]]<br />
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Category:Quantum mechanics<br />
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类别: 量子力学<br />
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* [[Quantum teleportation]]<br />
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Category:Unsolved problems in physics<br />
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类别: 物理学中未解决的问题<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Quantum entanglement]]. Its edit history can be viewed at [[量子纠缠/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%87%8F%E5%AD%90%E7%BA%A0%E7%BC%A0&diff=21230量子纠缠2021-01-23T11:58:59Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译。<br />
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{{short description|Correlation between measurements of quantum subsystems, even when spatially separated}}<br />
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[[File:SPDC figure.png|right|thumb|275px|[[Spontaneous parametric down-conversion]] process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[[Spontaneous parametric down-conversion process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[自发参量下转换过程可以将光子分裂成具有相互垂直极化的 II 型光子对。]<br />
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{{Quantum mechanics|fundamentals}}<br />
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'''Quantum entanglement''' is a physical phenomenon that occurs when a pair or group of [[particle]]s are generated, interact, or share spatial proximity in a way such that the [[quantum state]] of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the [[principle of locality|disparity between classical and quantum physics]]: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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量子纠缠是一种物理现象,描述的是当一对或一组粒子被产生、相互作用或共享空间邻近性时(包括当粒子被大距离分离时),该对或该组粒子中的每个粒子的量子态都无法独立于其他粒子的态。量子纠缠是经典物理学和量子物理学之间差别悬殊的核心问题:纠缠是量子力学的一个主要特征,而经典力学却没有这种特征。<br />
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[[Measurement#Quantum mechanics|Measurements]] of [[physical properties]] such as [[position (vector)|position]], [[momentum]], [[spin (physics)|spin]], and [[polarization (waves)|polarization]] performed on entangled particles can, in some cases, be found to be perfectly [[correlated]]. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly [[paradox]]ical effects: any measurement of a property of a particle results in an irreversible [[wave function collapse]] of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a property of a particle results in an irreversible wave function collapse of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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在某些情况下,对纠缠粒子的位置、动量、自旋和偏振等物理性质的测量的结果可以是完全相关的。例如,如果一对纠缠粒子的产生使得它们的总自旋已知为零,并且我们发现一个粒子在第一个轴上具有顺时针自旋,那么在同一个轴上测量的另一个粒子的自旋将会是逆时针的。然而,这种行为产生了看似矛盾的效应:对粒子性质的任何测量都会导致该粒子的不可逆波函数崩溃,并将改变原来的量子态。在粒子纠缠的情况下,这样的测量将影响整个纠缠系统。<br />
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Such phenomena were the subject of a 1935 paper by [[Albert Einstein]], [[Boris Podolsky]], and [[Nathan Rosen]],<ref name="Einstein1935"><br />
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Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen, and several papers by Erwin Schrödinger shortly thereafter, describing what came to be known as the EPR paradox. Einstein and others considered such behavior to be impossible, as it violated the local realism view of causality (Einstein referring to it as "spooky action at a distance") and argued that the accepted formulation of quantum mechanics must therefore be incomplete.<br />
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这些现象是阿尔伯特·爱因斯坦、鲍里斯·波多尔斯基和纳森·罗森在1935年发表的一篇论文和埃尔文·薛定谔随后不久发表的几篇论文的主题,这些论文描述了后来的EPR悖论。爱因斯坦和其他人认为这样的行为是不可能的,因为它违反了因果关系的局部实在论观点(爱因斯坦称之为“远处的幽灵行为”),并认为量子力学的公认公式因此一定是不完整的。<br />
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{{cite journal|author=Einstein A, Podolsky B, Rosen N|last2=Podolsky|last3=Rosen|year=1935|title=Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?|journal=Phys. Rev.|volume=47|issue=10|pages=777–780|bibcode=1935PhRv...47..777E|doi=10.1103/PhysRev.47.777|doi-access=free}}<br />
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</ref> and several papers by [[Erwin Schrödinger]] shortly thereafter,<ref name="Schrödinger1935"><br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<br />
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然而,后来,量子力学的反直觉预测在实验上得到了验证。所谓的“无漏洞”钟试验已经进行,在这种试验中,粒子位置被分开,以光速进行的通信将花费更长的时间——在一次实验中比测量间隔长10000倍<br />
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|author=Schrödinger E<br />
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According to some interpretations of quantum mechanics, the effect of one measurement occurs instantly. Other interpretations which don't recognize wavefunction collapse dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces correlation between the measurements and that the mutual information between the entangled particles can be exploited, but that any transmission of information at faster-than-light speeds is impossible.<br />
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根据量子力学的一些解释,一次测量的效果是瞬间发生的。其他不承认波函数崩塌的解释则认为不存在任何“效应”。然而,所有的解释都同意,纠缠产生了测量之间的相关性,纠缠粒子之间的互信息可以被利用,但任何信息的传输速度都不可能超过光速。<br />
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|title=Discussion of probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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Quantum entanglement has been demonstrated experimentally with photons, neutrinos, electrons, molecules as large as buckyballs, and even small diamonds. The utilization of entanglement in communication, computation and quantum radar is a very active area of research and development.<br />
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量子纠缠已经在光子、中微子、电子、巴基球大小的分子,甚至小钻石的实验中得到证实。纠缠在通信、计算和量子雷达中的应用是一个非常活跃的研究和发展领域。<br />
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|volume=31<br />
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|issue=4<br />
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|pages=555–563<br />
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Article headline regarding the [[Einstein–Podolsky–Rosen paradox (EPR paradox) paper, in the May 4, 1935 issue of The New York Times.]]<br />
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文章标题关于[爱因斯坦-波多尔斯基-罗森悖论(EPR paradox)论文,发表于1935年5月4日的《纽约时报》]<br />
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|year=1935<br />
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|doi=10.1017/S0305004100013554<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.<br />
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1935年,阿尔伯特·爱因斯坦与鲍里斯·波多尔斯基和纳森·罗森在一篇联合论文中首次讨论了量子力学关于强关联系统的反直觉预测。 <br />
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|bibcode = 1935PCPS...31..555S }}</ref><ref name="Schrödinger1936"><br />
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{{cite journal |author=Schrödinger E<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated: Einstein later famously derided entanglement as "spukhafte Fernwirkung" or "spooky action at a distance."<br />
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此后不久,薛定谔发表了一篇影响深远的论文,定义并讨论了“纠缠”的概念在论文中,他承认了这个概念的重要性,并指出了爱因斯坦后来众所周知的对纠缠的嘲弄“幽灵般的超距作用”<br />
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|title=Probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously Bohm's interpretation of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when John Stewart Bell proved that one of their key assumptions, the principle of locality, as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是Bohm对量子力学的解释),但发表的其他工作相对较少。尽管如此,直到1964年,约翰·斯图尔特·贝尔(John Stewart Bell)证明了他们的一个关键假设,即应用于EPR所希望的隐变量解释的局部性原理,在数学上与量子理论的预测不一致,EPR的论点中的弱点至此才被发现。<br />
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|volume=32<br />
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|issue=3<br />
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Specifically, Bell demonstrated an upper limit, seen in Bell's inequality, regarding the strength of correlations that can be produced in any theory obeying local realism, and showed that quantum theory predicts violations of this limit for certain entangled systems. His inequality is experimentally testable, and there have been numerous relevant experiments, starting with the pioneering work of Stuart Freedman and John Clauser in 1972 and Alain Aspect's experiments in 1982. An early experimental breakthrough was due to Carl Kocher, Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles. Alain Aspect notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / superdeterminism loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<br />
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具体来说,贝尔证明了一个上限,可以在贝尔不等式中看到,关于遵循局部实在论的任何理论中可以产生的关联强度,并表明量子理论预测某些纠缠系统会违反这个极限。从1972年斯图亚特·弗里德曼和约翰·克劳瑟的开创性工作和1982年阿兰·阿斯佩的实验开始,他的不等式在实验上是可以检验的,并且存在许多相关的实验。早期的实验突破归功于卡尔·科彻,科彻的仪器配备了更好的偏振器,弗里德曼和克劳瑟使用了这种仪器,他们可以证实余弦平方依赖性,并用它来证明对一组固定角度的贝尔不等式的违反。阿兰·阿斯佩指出的则是“设置独立漏洞”——他称之为“牵强的”,然而,“不可忽视”的“剩余漏洞”——还没有被关闭,并且自由意志/超决定论的漏洞是无法弥补的;他说“没有任何实验,尽可能的理想情况,可以说是完全没有漏洞的。” <br />
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|pages=446–452<br />
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|year=1936<br />
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A minority opinion holds that although quantum mechanics is correct, there is no superluminal instantaneous action-at-a-distance between entangled particles once the particles are separated.<br />
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少数人认为,尽管量子力学是正确的,但是一旦粒子分离,纠缠的粒子之间并不存在超光速瞬时作用。<br />
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|doi=10.1017/S0305004100019137<br />
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|bibcode = 1936PCPS...32..446S }}<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of quantum key distribution protocols, most famously BB84 by Charles H. Bennett and Gilles Brassard and E91 by Artur Ekert. Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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贝尔的工作提出了利用这些超强相关性作为交流资源的可能性。它导致了1984年量子密钥分配协议的发现,其中最著名的是查尔斯·H·班纳特和吉尔斯 布拉萨德的BB84和艾特 艾克特的E91。虽然BB84不使用纠缠,但是艾克特的协议使用了对Bell不等式的违反作为安全性的证明。 <br />
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</ref> describing what came to be known as the [[EPR paradox]]. Einstein and others considered such behavior to be impossible, as it violated the [[local realism]] view of causality (Einstein referring to it as "spooky [[action at a distance]]")<ref>Physicist John Bell depicts the Einstein camp in this debate in his article entitled "Bertlmann's socks and the nature of reality", p. 143 of ''Speakable and unspeakable in quantum mechanics'': "For EPR that would be an unthinkable 'spooky action at a distance'. To avoid such action at a distance they have to attribute, to the space-time regions in question, real properties in advance of observation, correlated properties, which predetermine the outcomes of these particular observations. Since these real properties, fixed in advance of observation, are not contained in quantum formalism, that formalism for EPR is incomplete. It may be correct, as far as it goes, but the usual quantum formalism cannot be the whole story." And again on p. 144 Bell says: "Einstein had no difficulty accepting that affairs in different places could be correlated. What he could not accept was that an intervention at one place could influence, immediately, affairs at the other." Downloaded 5 July 2011 from {{cite book |year=1987 |accessdate=2014-06-14 |title=Speakable and Unspeakable in Quantum Mechanics |first=J. S. |last=Bell |publisher=[[CERN]] |isbn=0521334950 |url=http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20150412044550/http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |archivedate=12 April 2015 |df=dmy-all }}</ref> and argued that the accepted formulation of [[quantum mechanics]] must therefore be incomplete.<br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally<ref name=":0" /><ref name=":1" /><ref name=":2" /> in tests in which polarization or spin of entangled particles were measured at separate locations, statistically violating [[Bell's inequality]]. In earlier tests, it couldn't be absolutely ruled out that the test result at one point could have been [[Loopholes in Bell test experiments|subtly transmitted]] to the remote point, affecting the outcome at the second location.<ref name=":2">Francis, Matthew.<br />
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[https://arstechnica.com/science/2012/10/quantum-entanglement-shows-that-reality-cant-be-local/ Quantum entanglement shows that reality can't be local], ''Ars Technica'', 30 October 2012</ref> However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<ref name=":1">{{cite journal|last1=Matson|first1=John|title=Quantum teleportation achieved over record distances|journal=Nature News|date=13 August 2012|doi=10.1038/nature.2012.11163|s2cid=124852641}}</ref><ref name=":0">{{cite journal<br />
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| title =Bounding the speed of 'spooky action at a distance<br />
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An entangled system is defined to be one whose quantum state cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or superposition, of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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一个纠缠系统被定义为一个量子态不能被分解为其局部成分的态的乘积的系统,也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部组分状态积的和或叠加;如果这个和必然有多个项,它就被纠缠。<br />
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| journal =Physical Review Letters |volume=110 | issue =26 |page=260407<br />
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| year =2013<br />
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Quantum systems can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on methods. Entanglement is broken when the entangled particles decohere through interaction with the environment; for example, when a measurement is made.<br />
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量子系统可以通过各种类型的相互作用而纠缠在一起。为了实验的目的,纠缠可以通过一些方法实现,请参见下面的方法部分。当纠缠的粒子通过与环境的相互作用而退离时,例如在进行测量时,纠缠就被打破了。 <br />
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| arxiv =1303.0614<br />
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| bibcode =2013PhRvL.110z0407Y<br />
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As an example of entanglement: a subatomic particle decays into an entangled pair of other particles. The decay events obey the various conservation laws, and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a spin-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be spin up on some axis, the other, when measured on the same axis, is always found to be spin down. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the singlet state.)<br />
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作为纠缠的一个例子:一个亚原子粒子衰变为一对纠缠的其他粒子。衰变事件遵循各种守恒定律,因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(以便总动量、角动量、能量等在此过程前后保持大致相同)。例如,一个自旋为零的粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量到自旋向上时,另一个粒子在同一个轴上被测量时,总是被发现是自旋向下。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于单线态)。<br />
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| doi = 10.1103/PhysRevLett.110.260407<br />
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| pmid =23848853 | last1 =Yin | first1 =Juan | last2 =Cao | first2 =Yuan | last3 =Yong | first3 =Hai-Lin | last4 =Ren | first4 =Ji-Gang | last5 =Liang | first5 =Hao | last6 =Liao | first6 =Sheng-Kai | last7 =Zhou | first7 =Fei | last8 =Liu | first8 =Chang | last9 =Wu | first9 =Yu-Ping | last10 =Pan | first10 =Ge-Sheng | last11 =Li | first11 =Li | last12 =Liu | first12 =Nai-Le | last13 =Zhang | first13 =Qiang | last14 =Peng | first14 =Cheng-Zhi | last15 =Pan | first15 =Jian-Wei | s2cid =119293698 }}</ref><br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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如果将这两种粒子分开,可以更好地观察到纠缠的特性。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫。现在,如果我们测量其中一个粒子的特性(比如自旋) ,得到一个结果,然后用同样的标准(沿着同样的轴自旋)测量另一个粒子,我们发现第二个粒子的测量结果将匹配(在补充意义上)第一个粒子的测量结果,因为它们的值将相反。<br />
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According to ''some'' [[interpretations of quantum mechanics]], the effect of one measurement occurs instantly. Other interpretations which don't recognize [[wavefunction collapse]] dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces ''[[correlation]]'' between the measurements and that the [[mutual information]] between the entangled particles can be exploited, but that any ''transmission'' of information at faster-than-light speeds is impossible.<ref>[[Roger Penrose]], ''The Road to Reality: A Complete Guide to the Laws of the Universe'', London, 2004, p. 603.</ref><ref name="Griffiths2004">{{citation | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |isbn= 978-0-13-111892-8}}</ref><br />
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根据“一些”[[量子力学的解释]],一次测量的效果瞬间发生。其他不承认[[波函数崩溃]]的解释则认为存在任何“效应”。然而,所有的解释都同意,纠缠在测量值之间产生了“[[相关]]”,并且纠缠粒子之间的[[互信息]]可以被利用,但是任何以高于光速的信息“传输”都是不可能的。 <br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a hidden variable theory (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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上述结果可能会或不会被认为是令人惊讶的。一个经典系统也会表现出同样的性质,而一个隐藏变量理论(见下文)肯定会被要求这样做,它建立在经典力学和量子力学的角动量守恒的基础上。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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Quantum entanglement has been demonstrated experimentally with [[photon]]s,<ref name="Kocher1">{{cite journal | doi = 10.1103/PhysRevLett.18.575 | volume=18 | issue=15 | title=Polarization Correlation of Photons Emitted in an Atomic Cascade | journal=Physical Review Letters | pages=575–577 | last1 = Kocher | first1 = CA | last2 = Commins | first2 = ED | year=1967| url=http://www.escholarship.org/uc/item/1kb7660q | bibcode=1967PhRvL..18..575K }}</ref><ref name="Kocherphd">Carl A. Kocher, Ph.D. Thesis (University of California at Berkeley, 1967). ''[https://escholarship.org/uc/item/1kb7660q Polarization Correlation of Photons Emitted in an Atomic Cascade]''</ref> [[neutrino]]s,<ref>J. A. Formaggio, D. I. Kaiser, M. M. Murskyj, and T. E. Weiss (2016), "[https://journals.aps.org/prl/accepted/6f072Y00C3318d41f5739ec7f83a9acf1ad67b002 Violation of the Leggett-Garg inequality in neutrino oscillations]". ''Phys. Rev. Lett.'' Accepted 23 June 2016.</ref> [[electron]]s,<ref name="NTR-20151021">{{cite journal |author=Hensen, B. |title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres |date=21 October 2015 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature15759 |display-authors=etal |volume=526 |issue=7575 |pages=682–686|bibcode = 2015Natur.526..682H |pmid=26503041|arxiv=1508.05949 |hdl=2117/79298 |s2cid=205246446 }} See also [http://www.nature.com/articles/nature15759.epdf?referrer_access_token=1QB20mTNTZW60nEXil0D79RgN0jAjWel9jnR3ZoTv0Pfu6MWINxm4Io03p2jIRZ8qX_3I3N0Kr-AlItuikCZOJrG8QbdRRghlecFwmixlbQpWuw1dtaib4Le5DQOG3u_aXHU85x1JEhOcQTa1sHi0yvW23bblxmEQZAmHL4G0gIVusG_6JWorroY5BprgbTl4FiaE8WltEgMoUMZfZBkEfbMcFDp5iR112TFx_x3ZRj88Wa23E2moEvTfKjtlued0&tracking_referrer=www.nytimes.com free online access version].</ref><ref name="NYT-20151021">{{cite news |last=Markoff |first=Jack |title=Sorry, Einstein. Quantum Study Suggests 'Spooky Action' Is Real. |url=https://www.nytimes.com/2015/10/22/science/quantum-theory-experiment-said-to-prove-spooky-interactions.html |date=21 October 2015 |work=The New York Times |accessdate=21 October 2015 }}</ref> [[molecule]]s as large as [[buckyball]]s,<ref>{{cite journal | doi = 10.1038/44348 | title = Wave–particle duality of C<sub>60</sub> molecules | date= 14 October 1999 | volume=401 | issue = 6754 | journal=Nature | pages=680–682 | pmid=18494170|bibcode = 1999Natur.401..680A | last1 = Arndt | first1 = M | last2 = Nairz | first2 = O | last3 = Vos-Andreae | first3 = J | last4 = Keller | first4 = C | last5 = van der Zouw | first5 = G | last6 = Zeilinger | first6 = A| s2cid = 4424892 }} {{subscription}}</ref><ref>[[Olaf Nairz]], [[Markus Arndt]], and [[Anton Zeilinger]], "Quantum interference experiments with large molecules", American Journal of Physics, 71 (April 2003) 319–325.</ref> and even small diamonds.<ref>{{cite journal |journal=Science |date=2 December 2011 |volume=334 |issue=6060 |pages=1253–1256 |doi=10.1126/science.1211914 |pmid=22144620 |url=http://www.sciencemag.org/content/334/6060/1253.full |title=Entangling macroscopic diamonds at room temperature |lay-url=https://www.newscientist.com/article/dn21235-entangled-diamonds-blur-quantumclassical-divide.html|bibcode = 2011Sci...334.1253L |last1=Lee |first1=K. C. |last2=Sprague |first2=M. R. |last3=Sussman |first3=B. J. |last4=Nunn |first4=J. |last5=Langford |first5=N. K. |last6=Jin |first6=X.- M. |last7=Champion |first7=T. |last8=Michelberger |first8=P. |last9=Reim |first9=K. F. |last10=England |first10=D. |last11=Jaksch |first11=D. |last12=Walmsley |first12=I. A. |s2cid=206536690 }}</ref><ref>[http://www.sciencemag.org/content/334/6060/1253/suppl/DC1 sciencemag.org], supplementary materials</ref> The utilization of entanglement in [[quantum communication|communication]], [[quantum computing|computation]] and [[quantum radar]] is a very active area of research and development.<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<br />
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矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能比光传播得快),因此确保纠缠对的另一部分的测量结果是“正确的”。在哥本哈根解释中,对其中一个粒子的自旋测量的结果是坍缩成一种状态,其中每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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== History 历史==<br />
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[[File:NYT May 4, 1935.jpg|right|thumb| 250px|Article headline regarding the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox) paper, in the May 4, 1935 issue of ''[[The New York Times]]''.]]<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, hence, any causal effect connecting the events would have to travel faster than light. According to the principles of special relativity, it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events and there are inertial frames in which is first and others in which is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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我们可以选择测量的距离和时间,以便使两次测量之间的间隔像空间一样,因此,连接事件的任何因果效应都必须比光传播得更快。根据狭义相对论的原理,任何信息都不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量值是第一个。对于两个分离的类空事件,存在惯性系,有惯性系在其中是第一位的,也有其他惯性系在其中是第一位的。因此,这两种测量之间的相关性不能解释为一种测量决定另一种测量:不同的观察者会对因果关系的作用产生分歧。<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by [[Albert Einstein]] in 1935, in a joint paper with [[Boris Podolsky]] and [[Nathan Rosen]].<ref name="Einstein1935"/><br />
1935年阿尔伯特 爱因斯坦与鲍里斯 波多斯基和纳兰 罗森在一篇联合论文中首次讨论了关于强关联系统的量子力学的反直觉预测。 <br />
(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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(事实上,即使没有纠缠,也会出现类似的悖论:单个粒子的位置分布在空间上,两个试图在两个不同位置检测粒子的大范围分离的探测器必须立即获得适当的相关性,这样它们就不会同时检测到粒子。)<br />
In this study, the three formulated the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox), a [[thought experiment]] that attempted to show that [[quantum mechanics|quantum mechanical theory]] was [[Incompleteness of quantum physics|incomplete]]. They wrote: "We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete."<ref name="Einstein1935"/><br />
在这项研究中,三人提出了[[爱因斯坦-波多尔斯基-罗森悖论]](EPR悖论),一个[[思维实验]],试图证明[[量子力学|量子力学理论]]是[[量子物理的不完全性|不完全性]]。他们写道:“因此,我们被迫得出结论,波函数给出的物理实在的量子力学描述并不完整。” <br />
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However, the three scientists did not coin the word ''entanglement'', nor did they generalize the special properties of the state they considered. Following the EPR paper, [[Erwin Schrödinger]] wrote a letter to Einstein in [[German language|German]] in which he used the word ''Verschränkung'' (translated by himself as ''entanglement'') "to describe the correlations between two particles that interact and then separate, as in the EPR experiment."<ref name=MK>Kumar, M., ''Quantum'', Icon Books, 2009, p. 313.</ref><br />
然而,这三位科学家并没有创造“纠缠”这个词,也没有概括出他们所考虑的状态的特殊性质。在EPR论文发表之后,[[埃尔温·薛定谔]]用德语给爱因斯坦写了一封信,信中他用“Verschränkung”(他自己翻译为“纠缠”)一词来描述两个相互作用然后分离的粒子之间的关联,就像EPR实验中那样。” <br />
A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables". The state of the particles being measured contains some hidden variables, whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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解决这一悖论的一个可能办法是假设量子理论是不完整的,测量结果取决于预先确定的“隐藏变量”。被测粒子的状态包含一些隐藏的变量,这些变量的值从分离的那一刻起就有效地决定了自旋测量的结果。这就意味着每个粒子都携带着所需的全部信息,在测量时不需要从一个粒子传输到另一个粒子。爱因斯坦和其他人(见上一节)最初认为这是摆脱悖论的唯一途径,而公认的量子力学描述(带有随机测量结果)肯定是不完整的。<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated:<ref name="Schrödinger1935"/> "I would not call [entanglement] ''one'' but rather ''the'' characteristic trait of [[quantum mechanics]], the one that enforces its entire departure from [[Classical mechanics|classical]] lines of thought."<br />
此后不久,薛定谔发表了一篇开创性的论文,对“纠缠”的概念进行了定义和讨论。在论文中,他认识到了这个概念的重要性,并指出:“我不会将[纠缠]称为‘一’,而是称之为[量子力学]的‘特性’。”,它完全背离了[[经典力学|经典]]的思路。” <br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the local realist or hidden variables view were correct, the results would always satisfy Bell's inequality. A number of experiments have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists. When measurements of the entangled particles are made in moving relativistic reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<br />
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然而,当考虑沿不同轴的纠缠粒子自旋的测量时,局部隐变量理论是失败的。如果进行了大量成对的此类测量(在大量成对的纠缠粒子上),那么在统计上,如果局部现实主义或隐藏变量的观点是正确的,结果将始终满足贝尔不等式。大量的实验表明,贝尔不等式在实践中是不成立的。然而,在2015年之前,被物理学家群体认为是最关键的是所有这些实践都有漏洞问题,。当在运动的相对论参考系中对纠缠粒子进行测量时,每个测量(在它自己的相对论时间范围内)都发生在另一个之前,测量结果将保持相关。<br />
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Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the [[theory of relativity]].<ref>Alisa Bokulich, Gregg Jaeger, ''Philosophy of Quantum Information and Entanglement'', Cambridge University Press, 2010, xv.</ref> Einstein later famously derided entanglement as "''spukhafte Fernwirkung''"<ref name="spukhafte">Letter from Einstein to Max Born, 3 March 1947; ''The Born-Einstein Letters; Correspondence between Albert Einstein and Max and Hedwig Born from 1916 to 1955'', Walker, New York, 1971. (cited in {{citation | title = Quantum Entanglement and Communication Complexity (1998) | journal = SIAM J. Comput. | volume = 30 | issue = 6 | citeseerx = 10.1.1.20.8324 | author = M. P. Hobson |pages=1829–1841 | display-authors = etal | year = 1998 }})</ref> or "spooky [[Action at a distance (physics)|action at a distance]]."<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are incompatible in the sense that these measurements' maximum simultaneous precision is constrained by the uncertainty principle. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations, and thus entanglement is a fundamentally non-classical phenomenon.<br />
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沿不同轴线测量自旋的基本问题是,这些测量不可能同时具有确定的值——它们是不相容的,因为这些测量的最大同时精度受到不确定性原理的限制。这与经典物理学中的发现相反,在经典物理学中,任何数量的性质都可以以任意精度同时测量。从数学上证明了相容测量不能显示违反贝尔不等式的关联,因此纠缠是一个基本的非经典现象。<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously [[De Broglie–Bohm theory|Bohm's interpretation]] of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when [[John Stewart Bell]] proved that one of their key assumptions, the [[principle of locality]], as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是量子力学的[[De Broglie–Bohm 理论 | Bohm表达]]),但其他发表的著作相对较少。尽管有人对此感兴趣,但直到1964年,[[约翰·斯图尔特·贝尔]]证明了他们的一个关键假设,[[局域性原理]],即应用于EPR希望解释的隐藏变量,在数学上与量子理论的预测不一致时,EPR论点中的漏洞才被发现。<br />
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Entanglement is required to preserve the Uncertainty principle, as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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纠缠是保持不确定性原理所必需的,如 EPR 悖论所示。例如,假设一个高能光子衰变成一个电子/正电子对,然后测量电子的位置和正电子的动量。如果我们在物理描述中不允许纠缠,那么每个粒子的位置和动量就可以通过参考动量守恒来推导,这就违反了测不准原理。或者,如果我们要求不确定性原理保持真实,而仍然不允许在物理上描述对的纠缠,不确定性原理将会违反动量守恒定律,因为在位置和动量上强相关性是不可能的(也就是说,人们不能有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关)。--><br />
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Specifically, Bell demonstrated an upper limit, seen in [[Bell's inequality]], regarding the strength of correlations that can be produced in any theory obeying [[local realism]], and showed that quantum theory predicts violations of this limit for certain entangled systems.<ref>{{cite journal |author = J. S. Bell |title = On the Einstein-Poldolsky-Rosen paradox |journal = Physics Physique Физика |volume = 1 |issue = 3 |pages = 195–200 |year = 1964|doi = 10.1103/PhysicsPhysiqueFizika.1.195 |doi-access = free }}</ref> His inequality is experimentally testable, and there have been numerous [[Bell test experiments|relevant experiments]], starting with the pioneering work of [[Stuart Freedman]] and [[John Clauser]] in 1972<ref name="Clauser">{{cite journal|doi=10.1103/PhysRevLett.28.938|last1=Freedman|first1=Stuart J.|last2=Clauser|first2=John F.|title=Experimental Test of Local Hidden-Variable Theories|journal=Physical Review Letters |volume=28 |issue=14 |pages=938–941|year=1972 |bibcode=1972PhRvL..28..938F|url=https://escholarship.org/uc/item/2f18n5nk}}</ref> and [[Alain Aspect]]'s experiments in 1982.<ref>{{cite journal |author1=A. Aspect |author2=P. Grangier |author3=G. Roger |name-list-style=amp |title = Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell's Inequalities |journal = Physical Review Letters |volume = 49 |issue = 2 |pages = 91–94 |year = 1982 |doi = 10.1103/PhysRevLett.49.91 |bibcode=1982PhRvL..49...91A|doi-access = free }}</ref> An early experimental breakthrough was due to Carl Kocher,<ref name="Kocher1"/><ref name="Kocherphd"/> who already in 1967 presented an apparatus in which two photons successively emitted from a calcium atom were shown to be entangled – the first case of entangled visible light. The two photons passed diametrically positioned parallel polarizers with higher probability than classically predicted but with correlations in quantitative agreement with quantum mechanical calculations. He also showed that the correlation varied only upon (as cosine square of) the angle between the polarizer settings<ref name="Kocherphd"/> and decreased exponentially with time lag between emitted photons.<ref name="Kocher2">{{cite journal | doi = 10.1016/0003-4916(71)90159-X | volume=65 | issue=1 | title=Time correlations in the detection of successively emitted photons | journal=Annals of Physics | pages=1–18 | last1 = Kocher | first1 = CA | year=1971| bibcode=1971AnPhy..65....1K }}</ref> Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles.<ref name="Clauser"/> All these experiments have shown agreement with quantum mechanics rather than the principle of local realism.<br />
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For decades, each had left open at least one [[Loopholes in Bell test experiments|loophole]] by which it was possible to question the validity of the results. However, in 2015 an experiment was performed that simultaneously closed both the detection and locality loopholes, and was heralded as "loophole-free"; this experiment ruled out a large class of local realism theories with certainty.<ref name="hanson">{{cite journal|last1=Hanson|first1=Ronald|title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres|journal=Nature|volume=526|issue=7575|pages=682–686|doi=10.1038/nature15759|arxiv=1508.05949|bibcode = 2015Natur.526..682H|pmid=26503041|year=2015|s2cid=205246446}}</ref> [[Alain Aspect]] notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / ''[[superdeterminism]]'' loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<ref>{{Cite journal | title=Viewpoint: Closing the Door on Einstein and Bohr's Quantum Debate| journal=Physics| volume=8| date=2015-12-16| last1=Aspect| first1=Alain| page=123| doi=10.1103/physics.8.123| doi-access=free| bibcode=2015PhyOJ...8..123A}}</ref><br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time. The authors claimed that this result was achieved by entanglement swapping between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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在2012年和2013年的实验中,在时间上从未共存的光子之间产生了偏振关联。作者认为,这一结果是在测量了一对纠缠光子的偏振态后,通过两对纠缠光子之间的纠缠交换得到的,证明了量子非定域性不仅适用于空间,也适用于时间。 <br />
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A minority opinion holds that although quantum mechanics is correct, there is no [[faster-than-light|superluminal]] instantaneous action-at-a-distance between entangled particles once the particles are separated.<ref>{{Cite journal |doi = 10.1142/S0217979206034078|title = Correlations in Entangled States|journal = International Journal of Modern Physics B|volume = 20|issue = 11n13|pages = 1496–1503|year = 2006|last1 = Sanctuary|first1 = B. C|arxiv = quant-ph/0508238|bibcode = 2006IJMPB..20.1496S|s2cid = 119403050}}</ref><ref>{{Cite arxiv |eprint = quant-ph/0404011 |last1 = Yin |first1 = Juan |title = The Statistical Interpretation of Entangled States |last2 = Cao |first2 = Yuan |last3 = Yong |first3 = Hai-Lin |last4 = Ren |first4 = Ji-Gang |last5 = Liang |first5 = Hao |last6 = Liao |first6 = Sheng-Kai |last7 = Zhou |first7 = Fei |last8 = Liu |first8 = Chang |last9 = Wu |first9 = Yu-Ping |last10 = Pan |first10 = Ge-Sheng |last11 = Zhang |first11 = Qiang |last12 = Peng |first12 = Cheng-Zhi |last13 = Pan |first13 = Jian-Wei |year = 2004 }}</ref><ref>{{cite journal|doi=10.1002/prop.201600044 | volume=65 | issue=6–8 | title=After Bell | year=2016 | journal=Fortschritte der Physik | page=1600044 | last1 = Khrennikov | first1 = Andrei}}</ref><ref>{{Cite journal |arxiv = 1603.08674|last1 = Yin|first1 = Juan|title = After Bell|journal = Fortschritte der Physik (Progress in Physics)|date=2017|volume = 65|issue = 1600014|pages = 6–8|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|bibcode = 2016arXiv160308674K}}</ref><ref>{{Cite journal |arxiv = quant-ph/0703251|last1 = Yin|first1 = Juan|title = Classical statistical distributions can violate Bell-type inequalities|journal = Journal of Physics A: Mathematical and Theoretical|volume = 41|issue = 8|pages = 085303|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|year = 2007|doi = 10.1088/1751-8113/41/8/085303|s2cid = 46193162}}</ref><br />
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In three independent experiments in 2013 it was shown that classically communicated separable quantum states can be used to carry entangled states. The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<br />
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2013年的三个独立实验表明,经典通信的可分离量子态可以用来携带纠缠态。第一次无漏洞贝尔试验于2015年在图代尔夫特举行,证实了贝尔不等式的不成立。 <br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of [[quantum key distribution]] protocols, most famously [[BB84]] by [[Charles H. Bennett (computer scientist)|Charles H. Bennett]] and [[Gilles Brassard]]<ref>C. H. Bennett and G. Brassard. "Quantum cryptography: Public key distribution and coin tossing". In ''Proceedings of IEEE International Conference on Computers, Systems and Signal Processing'', volume 175, p. 8. New York, 1984. http://researcher.watson.ibm.com/researcher/files/us-bennetc/BB84highest.pdf</ref> and [[E91 protocol|E91]] by [[Artur Ekert]].<ref>{{cite journal|last=Ekert|first=A.K.|authorlink=Artur Ekert|title=Quantum cryptography based on Bell's theorem|journal=Phys. Rev. Lett.|volume=67|issue=6|year=1991|doi=10.1103/PhysRevLett.67.661|issn=0031-9007|bibcode = 1991PhRvL..67..661E|pmid=10044956|pages=661–663}}</ref> Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<br />
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2014年8月,巴西研究人员加布里埃拉·巴雷托·莱莫斯和他的团队能够使用光子“拍摄”物体,这些光子并没有与实验对象发生相互作用,而是与这些物体发生了纠缠。来自维也纳大学的勒莫斯相信,这种新的量子成像技术可以在微光成像势在必行的领域找到应用,比如生物或医学成像。<br />
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== Concept 概念==<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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2015年,哈佛大学的马克斯·格雷纳团队直接测量了超冷玻色子原子系统中的Renyi纠缠。<br />
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=== Meaning of entanglement纠缠的意义 ===<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<br />
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从2016年起,IBM、微软等多家公司成功创建了量子计算机,并允许开发人员和技术爱好者公开实验量子力学的概念,这其中就包括量子纠缠。 <br />
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An entangled system is defined to be one whose [[quantum state]] cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or [[quantum superposition|superposition]], of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
纠缠系统被定义为其[[量子态]]不能被分解为其局部成分的态的乘积;也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部成分的状态积的和,或[[量子叠加|叠加]],如果这个和一定有一个以上的项,那么它是纠缠的。<br />
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Quantum [[physical system|systems]] can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on [[#Methods of creating entanglement|methods]]. Entanglement is broken when the entangled particles [[quantum decoherence|decohere]] through interaction with the environment; for example, when a measurement is made.<ref name="Peres1993">Asher Peres, ''[[Quantum Theory: Concepts and Methods]]'', Kluwer, 1993; {{ISBN|0-7923-2549-4}} p. 115.</ref><br />
量子[[物理系统|系统]]可以通过各种类型的相互作用而纠缠在一起。为了实验目的而实现纠缠的一些方法,请参见下面关于[[#创建纠缠的方法|方法]]的部分。当纠缠粒子通过与环境的相互作用[[量子退相干|退相干]]时,例如在进行测量时,纠缠将被打破。<br />
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There have been suggestions to look at the concept of time as an emergent phenomenon that is a side effect of quantum entanglement.<br />
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有人建议把时间的概念看作是量子纠缠的副作用的一种自然现象。<br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by Don Page and William Wootters in 1983.<br />
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换句话说,时间是一种纠缠现象,它将所有相等的时钟读数(正确准备的时钟或任何可用作时钟的物体的读数)放入同一个历史中。1983年,唐·佩奇和威廉·伍特斯首次提出了这一理论<br />
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As an example of entanglement: a [[subatomic particle]] [[Particle decay|decays]] into an entangled pair of other particles. The decay events obey the various [[conservation laws]], and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a [[Spin (physics)|spin]]-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be [[Spin (physics)#Direction|spin up]] on some axis, the other, when measured on the same axis, is always found to be [[Spin (physics)#Direction|spin down]]. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the [[singlet state]].)<br />
作为纠缠的一个例子:一个[[亚原子粒子]][[粒子衰变|衰变]]变成一对纠缠的其他粒子。衰变事件遵循各种[[守恒定律]],因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(因此总动量、角动量、能量等在此过程前后保持大致相同)。例如,[[自旋(物理)|自旋]]-零粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量为[[自旋(物理)方向|自旋向上]],另一个粒子在同一个轴上被测量时,总是被发现为[[自旋(物理)#方向|自旋向下]]。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于[[单态]]。)<br />
The Wheeler–DeWitt equation that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<br />
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20世纪60年代,惠勒-德威特方程引入了广义相对论和量子力学的概念,并于1983年再次引入,当时佩奇和伍特基于量子纠缠方程提出了一个解决方案。佩奇和伍特斯认为纠缠态可以用来测量时间。<br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
将这两个粒子分开,可以更好地观察到纠缠的特殊性质。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫(把这当成一个思维实验,而不是实际的实验)。现在,如果我们测量其中一个粒子的特定特性(例如,自旋),得到一个结果,然后使用相同的标准测量另一个粒子(沿相同的轴自旋),我们发现第二个粒子的测量结果将与第一个粒子的测量结果相匹配(在互补意义上)粒子,因为它们的值是相反的<br />
In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts. The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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2013年,在意大利都灵的国家理查尔卡计量研究所(INRIM) ,研究人员对佩奇和伍特的想法进行了首次实验测试。他们的结果被解释为证实了对于内部观察者来说时间是一种涌现的现象,但正如惠勒-德威特方程所预测的那样,对于宇宙的外部观察者来说时间是不存在的。纠缠的方法是从因果时间箭头的角度出发,假设一个粒子被测量的原因决定了另一个粒子测量结果的效应。<br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a [[hidden variable theory]] (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
上述结果可能会或不会被认为是令人惊讶的。一个经典系统将显示出相同的性质,而[[隐藏变量理论]](见下文)肯定需要这样做,基于经典和量子力学中的角动量守恒。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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===Paradox矛盾===<br />
Based on AdS/CFT correspondence, Mark Van Raamsdonk suggested that spacetime arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time. Induced gravity can emerge from the entanglement first law.<br />
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基于AdS/CFT对应关系, Mark Van Raamsdonk提出时空是量子自由度的一种涌现现象,量子自由度纠缠在时空的边界上。诱导引力可以从纠缠第一定律中产生。<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel [[faster than light]]) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the [[Copenhagen interpretation]], the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<ref>{{cite book|last1=Rupert W.|first1=Anderson|title=The Cosmic Compendium: Interstellar Travel|date=28 March 2015|publisher=The Cosmic Compendium|isbn=9781329022027|page=100|edition=First|url=https://books.google.com/books?id=JxauCQAAQBAJ&pg=PA100&lpg=PA100&dq=The+outcome+is+taken+to+be+random,+with+each+possibility+having+a+probability+of+50%25.+However,+if+both+spins+are+measured+along+the+same+axis,+they+are+found+to+be+anti-correlated.+This+means+that+the+random+outcome+of+the+measurement+made+on+one+particle+seems+to+have+been+transmitted+to+the+other,+so+that+it+can+make+the+%22right+choice%22+when+it+too+is+measured#v=onepage}}</ref><br />
矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能传播[[比光更快]]),从而确保纠缠对的另一部分的测量的“正确”结果。在[[哥本哈根解释]]中,其中一个粒子的自旋测量结果是坍缩成一种状态,在这种状态下,每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements [[spacelike]], hence, any causal effect connecting the events would have to travel faster than light. According to the principles of [[special relativity]], it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events {{math|''x''<sub>1</sub>}} and {{math|''x''<sub>2</sub>}} there are [[inertial frame]]s in which {{math|''x''<sub>1</sub>}} is first and others in which {{math|''x''<sub>2</sub>}} is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
可以选择测量的距离和时间,以便使两次测量之间的间隔[[类太空]],因此,任何与事件相关的因果效应都必须比光传播得更快。根据[[狭义相对论]]的原理,任何信息不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量值是第一个。对于两个类空分离事件{{math |''x'<sub>1</sub>}和{math |''x'<sub>2</sub>}存在[[惯性系]],其中{{math |''x'<sub>1</sub>}是第一个,而其他事件中{math |''x'<sub>2</sub>}是第一个。因此,这两种测量之间的相关性不能解释为一种测量决定另一种测量:不同的观察者会对因果关系的作用产生分歧。 <br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations. A well-known example is the Werner states that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables. Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<br />
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在媒体和大众科学中,量子非定域性常常被描述为与纠缠等价。虽然这对于纯二部量子态是正确的,但一般来说纠缠只对非局域关联是必要的,但是存在不产生这种关联的混合纠缠态。一个著名的例子是沃纳态,它纠缠在<math>p{sym}</math>的某些值上,但总是可以用局部隐藏变量来描述。此外,研究还表明,对于任意数目的当事方,存在真正纠缠但允许局部模型的态。<br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all distillable states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<br />
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上述关于局部模型存在性的证明假设一次只有一个量子态的副本可用。如果允许当事方对这些态的许多副本进行局部测量,那么许多明显的局部态(例如量子比特-沃纳态)就不能再由局部模型来描述。这尤其适用于所有蒸馏态。然而,当有足够多的拷贝时,所有的纠缠态是否都变成非局域态仍是一个悬而未决的问题。<br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
(事实上,即使没有纠缠,也会出现类似的悖论:单个粒子的位置分布在空间上,两个试图在两个不同位置检测粒子的大范围分离的探测器必须立即获得适当的相关性,这样它们就不会同时检测到粒子。)<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to quantum teleportation and to superdense coding, whereas non-locality is defined according to experimental statistics and is much more involved with the foundations and interpretations of quantum mechanics.<br />
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简言之,双方共享的一个状态的纠缠是必要的,但不足以使该状态成为非局部的。必须认识到,纠缠更普遍地被视为一个代数概念,因为它是非定域性、量子隐形传态和超密集编码的先决条件,而非定域性是根据实验统计定义的,它更多地涉及到量子力学的基础和解释。<br />
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=== Hidden variables theory 隐藏变量理论===<br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables".<ref>{{Cite news|url=https://www.scientificamerican.com/article/cosmic-test-bolsters-einsteins-ldquo-spooky-action-at-a-distance-rdquo/?WT.mc_id=SA_FB_PHYS_NEWS|title=Cosmic Test Bolsters Einstein's "Spooky Action at a Distance"|last=magazine|first=Elizabeth Gibney, Nature|newspaper=Scientific American|language=en|access-date=2017-02-04}}</ref> The state of the particles being measured contains some [[hidden-variable theory|hidden variables]], whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of quantum mechanics, including familiarity with the formalism and theoretical framework developed in the articles: bra–ket notation and mathematical formulation of quantum mechanics.<br />
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以下小节是为那些对量子力学的形式化、数学描述有良好工作知识的人准备的,包括熟悉文章中发展的形式主义和理论框架:bra–ket符号和量子力学的数学公式。<br />
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=== Violations of Bell's inequality 贝尔不等式的违反===<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the [[local realism|local realist]] or hidden variables view were correct, the results would always satisfy [[Bell's inequality]]. A [[Bell test experiments|number of experiments]] have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists.<ref>{{citation |author1=I. Gerhardt |author2=Q. Liu |author3=A. Lamas-Linares |author4=J. Skaar |author5=V. Scarani |author6=V. Makarov |author7=C. Kurtsiefer |year=2011 |title=Experimentally faking the violation of Bell's inequalities |journal=Phys. Rev. Lett. |volume=107 |issue=17 |page=170404 |arxiv=1106.3224 |doi=10.1103/PhysRevLett.107.170404 |bibcode=2011PhRvL.107q0404G |pmid=22107491|s2cid=16306493 }}</ref><ref>{{cite journal | last1 = Santos | first1 = E | year = 2004 | title = The failure to perform a loophole-free test of Bell's Inequality supports local realism | url = | journal = Foundations of Physics | volume = 34 | issue = 11| pages = 1643–1673 | doi=10.1007/s10701-004-1308-z|bibcode = 2004FoPh...34.1643S | s2cid = 123642560 }}</ref> When measurements of the entangled particles are made in moving [[special relativity|relativistic]] reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<ref>{{cite journal |author = H. Zbinden |title = Experimental test of nonlocal quantum correlations in relativistic configurations |journal = Phys. Rev. A |volume = 63 |issue = 2 |pages = 22111 |doi = 10.1103/PhysRevA.63.022111|year = 2001|arxiv = quant-ph/0007009 |bibcode = 2001PhRvA..63b2111Z |display-authors = 1 |last2 = Gisin |last3 = Tittel |s2cid = 44611890 |url = http://archive-ouverte.unige.ch/unige:37034 }}</ref><ref name=LG>Some of the history of both referenced Zbinden, et al. experiments is provided in Gilder, L., ''The Age of Entanglement'', Vintage Books, 2008, pp. 321–324.</ref><br />
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Consider two arbitrary quantum systems and , with respective Hilbert spaces and . The Hilbert space of the composite system is the tensor product<br />
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考虑两个任意的量子系统,分别用Hilbert空间和(?)。复合系统的Hilbert空间是张量积 <br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are [[Incompatible observables|incompatible]] in the sense that these measurements' maximum simultaneous precision is constrained by the [[uncertainty principle]]. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations,<ref>{{cite journal|last1=Cirel'son|first1=B. S.|title=Quantum generalizations of Bell's inequality|journal=Letters in Mathematical Physics|volume=4|issue=2|pages=93–100| year=1980|doi=10.1007/BF00417500|bibcode=1980LMaPh...4...93C|s2cid=120680226}}</ref> and thus entanglement is a fundamentally non-classical phenomenon.<br />
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<math> H_A \otimes H_B.</math><br />
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Entanglement is required to preserve the [[Uncertainty principle]], as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
纠缠是保持[[不确定性原理]]所必需的,如EPR悖论所示。例如,假设一个高能光子衰变成电子/正电子对,然后测量电子的位置和正电子的动量。如果在对的物理描述中不允许纠缠,那么每个粒子的位置和动量仍然可以通过动量守恒来推导,这违反了测不准原理。或者,如果我们要求测不准原理成立,并且仍然不允许在对的物理描述中纠缠,那么测不准原理将允许违反动量守恒定律,因为位置和动量之间的强相关性是不可能的(即人们无法有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关。--> <br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态 < math > scriptstyle | psi rangle _ a </math > ,而第二个系统处于状态 < math > scriptstyle | phi rangle _ b </math > ,则复合系统的状态为<br />
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=== Other types of experiments其他类型的试验 ===<br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time.<ref name="Xiao-song2012">{{cite journal |author=Xiao-song Ma, Stefan Zotter, Johannes Kofler, Rupert Ursin, Thomas Jennewein, Časlav Brukner & Anton Zeilinger |title=Experimental delayed-choice entanglement swapping |journal=Nature Physics |volume=8 |issue=6 |pages=480–485 |date=26 April 2012 |doi=10.1038/nphys2294|arxiv = 1203.4834 |bibcode = 2012NatPh...8..480M |last2=Zotter |last3=Kofler |last4=Ursin |last5=Jennewein |last6=Brukner |last7=Zeilinger |s2cid=119208488 }}</ref><ref>{{cite journal | last1 = Megidish | first1 = E. | last2 = Halevy | first2 = A. | last3 = Shacham | first3 = T. | last4 = Dvir | first4 = T. | last5 = Dovrat | first5 = L. | last6 = Eisenberg | first6 = H. S. | year = 2013 | title = Entanglement Swapping between Photons that have Never Coexisted | url = | journal = Physical Review Letters | volume = 110 | issue = 21| page = 210403| doi=10.1103/physrevlett.110.210403|arxiv = 1209.4191 |bibcode = 2013PhRvL.110u0403M | pmid=23745845| s2cid = 30063749 }}</ref> The authors claimed that this result was achieved by [[Quantum teleportation#Entanglement swapping|entanglement swapping]] between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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<math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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In three independent experiments in 2013 it was shown that [[classical physics|classically communicated]] [[separable state|separable quantum states]] can be used to carry entangled states.<ref>{{cite web|url=http://physicsworld.com/cws/article/news/2013/dec/11/classical-carrier-could-create-entanglement |title=Classical carrier could create entanglement |publisher=physicsworld.com |accessdate=2014-06-14|date=2013-12-11 }}</ref> The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<ref>{{cite web | url=http://hansonlab.tudelft.nl/loophole-free-bell-test/ | title=Loophole-free Bell test &#124; Ronald Hanson | access-date=24 October 2015 | archive-url=https://web.archive.org/web/20180704082456/http://hansonlab.tudelft.nl/loophole-free-bell-test/ | archive-date=4 July 2018 | url-status=dead }}</ref><br />
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States of the composite system that can be represented in this form are called separable states, or product states.<br />
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可以用这种形式表示的复合系统状态称为可分状态或乘积状态。<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<ref>{{Cite journal|url=http://www.nature.com/news/entangled-photons-make-a-picture-from-a-paradox-1.15781|title=Entangled photons make a picture from a paradox|journal=Nature|accessdate=13 October 2014|doi=10.1038/nature.2014.15781|year=2014|last1=Gibney|first1=Elizabeth|s2cid=124976589}}</ref><br />
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Not all states are separable states (and thus product states). Fix a basis <math>\scriptstyle \{|i \rangle_A\}</math> for and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for . The most general state in is of the form<br />
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并非所有状态都是可分状态(因此也就是乘积状态)。修复一个基础 < math > scriptstyle { | i rangle _ a } </math > for 和一个基础 < math > scriptstyle { | j rangle _ b } </math > for。最普遍的状态是形式<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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<math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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[数学] | psi rangle { AB } = sum { i,j } c { ij } | i rangle _ a otimes | j rangle _ b </math > 。<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<ref>{{Cite journal|last=Rozatkar|first=Gaurav|date=2018-08-16|title=Demonstration of quantum entanglement|url=https://osf.io/g8bpj/|journal=OSF|language=en}}</ref><br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > ,那么这种状态是可分的,因此 < math scriptstyle c { ij } = c ^ a _ ic ^ b _ j,</math > 产生 < math scriptstyle | psi rangle _ a = sum { i } c ^ a _ { i } | i } | i _ a </math > 和 < math > phi scriptstyle | b = sum { j } | j } | j rangle b = sum { j }。如果对于任何向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > 至少对于一对坐标 < math > scriptstyle c ^ a _ i,c ^ b _ j </math > 我们有 < math > scriptstyle c _ { ij } neq c ^ a _ ic ^ b _ j。如果一种状态是不可分割的,那么它被称为“纠缠态”。<br />
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=== Mystery of time ===<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of , the following is an entangled state:<br />
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例如,给定两个基向量{ | 0 rangle _ a,| 1 rangle _ a } </math > 和两个基向量{ | 0 rangle _ b,| 1 rangle _ b } </math > ,下面是一个纠缠态:<br />
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There have been suggestions to look at the concept of time as an [[emergent phenomenon]] that is a side effect of quantum entanglement.<ref>{{Cite journal|title= Time from quantum entanglement: an experimental illustration|arxiv=1310.4691|bibcode = 2014PhRvA..89e2122M |doi = 10.1103/PhysRevA.89.052122|volume=89|issue= 5|pages=052122|journal=Physical Review A|year=2014 | last1 = Moreva | first1 = Ekaterina|s2cid=118638346}}</ref><ref>{{cite web|url=https://www.newscientist.com/article/dn24473-entangled-toy-universe-shows-time-may-be-an-illusion.html#.U8_-ApSSx2A|title=Entangled toy universe shows time may be an illusion|publisher=|accessdate=13 October 2014}}</ref><br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by [[Don Page (physicist)|Don Page]] and [[William Wootters]] in 1983.<ref>David Deutsch, The Beginning of infinity. Page 299</ref><br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right)<br />
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The [[Wheeler–DeWitt equation]] that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<ref name="medium.com">{{cite web|url=https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933|title=Quantum Experiment Shows How Time 'Emerges' from Entanglement|website=Medium|accessdate=13 October 2014|date=2013-10-23}}</ref><br />
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If the composite system is in this state, it is impossible to attribute to either system or system a definite pure state. Another way to say this is that while the von Neumann entropy of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry. The above example is one of four Bell states, which are (maximally) entangled pure states (pure states of the space, but which cannot be separated into pure states of each and ).<br />
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如果组合系统处于这种状态,就不可能给任何一个系统或系统一个确定的纯状态。另一种说法是,尽管整个状态的冯纽曼熵为零(对于任何纯状态都是如此) ,但子系统的熵大于零。从这个意义上说,这两个系统是“纠缠”的。这对干涉测量法有具体的经验影响。上面的例子是四个贝尔态之一,它们是(最大)纠缠纯态(空间的纯态,但不能分离成每个和的纯态)。<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted{{by whom|date=August 2020}} to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts.<ref name="medium.com"/><br />
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Now suppose Alice is an observer for system , and Bob is an observer for system . If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of , there are two possible outcomes, occurring with equal probability:<br />
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现在假设 Alice 是系统的观察者,而 Bob 是系统的观察者。如果在上面给出的纠缠态中,爱丽丝在[ | 0 rangle,| 1 rangle ] </math 本征基中进行测量,有两种可能的结果,发生的概率相等:<br />
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=== Source for the arrow of time ===<br />
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Physicist [[Seth Lloyd]] says that [[quantum uncertainty]] gives rise to entanglement, the putative source of the [[arrow of time]]. According to Lloyd; "The arrow of time is an arrow of increasing correlations."<ref>{{Cite journal|url=https://www.wired.com/2014/04/quantum-theory-flow-time/|title=New Quantum Theory Could Explain the Flow of Time|journal=Wired|accessdate=13 October 2014|date=2014-04-25|last1=Wolchover|first1=Natalie}}</ref> The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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Alice 测量0,系统的状态崩溃为 < math > scriptstyle | 0 rangle _ a | 1 rangle _ b </math > 。<br />
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Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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Alice 测量1,系统的状态崩溃为 < math > scriptstyle | 1 rangle _ a | 0 rangle _ b </math > 。<br />
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=== Emergent gravity ===<br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system has been altered by Alice performing a local measurement on system . This remains true even if the systems and are spatially separated. This is the foundation of the EPR paradox.<br />
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如果前者发生,那么 Bob 在相同基础上执行的任何后续测量都将返回1。如果出现后一种情况,(Alice 度量1) ,那么 Bob 的度量将确定返回0。因此,Alice 对系统进行了本地测量,从而对系统进行了更改。即使系统和空间上是分开的,这也是正确的。这就是 EPR 悖论的基础。<br />
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Based on [[AdS/CFT correspondence]], [[Mark Van Raamsdonk]] suggested that [[spacetime]] arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time.<ref>{{Cite journal|last=Van Raamsdonk|first=Mark|date=2010-06-19|title=Building up spacetime with quantum entanglement|journal=General Relativity and Gravitation|language=en|volume=42|issue=10|pages=2323–2329|doi=10.1007/s10714-010-1034-0|issn=0001-7701|arxiv=1005.3035|bibcode=2010GReGr..42.2323V}}</ref> [[Induced gravity]] can emerge from the entanglement first law.<ref>{{Cite journal|last1=Lee|first1=Jae-Weon|last2=Kim|first2=Hyeong-Chan|last3=Lee|first3=Jungjai|date=2013|title=Gravity from quantum information|journal=Journal of the Korean Physical Society|language=en|volume=63|issue=5|pages=1094–1098|doi=10.3938/jkps.63.1094|issn=0374-4884|arxiv=1001.5445|bibcode=2013JKPS...63.1094L|s2cid=118494859}}</ref><ref>{{cite arxiv|last1=Swingle|first1=Brian|last2=Van Raamsdonk|first2=Mark|date=2014-05-12|title=Universality of Gravity from Entanglement|eprint=1405.2933 |class=hep-th}}</ref><br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem.<br />
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爱丽丝的测量结果是随机的。Alice 不能决定将组合系统折叠到哪个状态,因此不能通过作用于她的系统将信息传递给 Bob。因此,在这个特定的方案中,因果关系被保留了下来。关于一般的论点,请参阅不交流定理。<br />
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== Non-locality and entanglement ==<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations.<ref name="Brunner-RMP2014">{{cite journal |title=Bell nonlocality |author1=Nicolas Brunner |author2=Daniel Cavalcanti |author3=Stefano Pironio |author4=Valerio Scarani |author5=Stephanie Wehner |journal=Rev. Mod. Phys. |volume=86 |issue=2 |pages=419–478 |date=2014 |doi=10.1103/RevModPhys.86.419 |arxiv=1303.2849|bibcode=2014RvMP...86..419B |s2cid=119194006 }}</ref> A well-known example is the [[Werner state]]s that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables.<ref name=werner1989>{{cite journal | last = Werner| first = R.F. | title = Quantum States with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model | journal = [[Physical Review A]] | volume = 40| pages = 4277–4281 | year = 1989 |doi=10.1103/PhysRevA.40.4277 | pmid=9902666 | issue=8|bibcode = 1989PhRvA..40.4277W }}</ref> Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<ref>{{cite journal|author=R. Augusiak, M. Demianowicz, J. Tura and A. Acín |title=Entanglement and Nonlocality are Inequivalent for Any Number of Parties |journal=Phys. Rev. Lett. |volume=115 |issue=3 |pages=030404 |year=2015 |arxiv=1407.3114 |doi=10.1103/PhysRevLett.115.030404|pmid=26230773 |hdl=2117/78836 |bibcode=2015PhRvL.115c0404A |s2cid=29758483 }}</ref><br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all [[entanglement distillation|distillable]] states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<ref>{{cite journal |title=Disproving the Peres conjecture: Bell nonlocality from bipartite bound entanglement |authors=Tamas Vértesi, Nicolas Brunner|year=2014 |journal=Nature Communications |volume=5 |issue=5297|page=5297 |doi=10.1038/ncomms6297 |pmid=25370352|arxiv=1405.4502 |s2cid=5135148}}</ref><br />
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As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a density matrix, which is a positive-semidefinite matrix, or a trace class when the state space is infinite-dimensional, and has trace 1. Again, by the spectral theorem, such a matrix takes the general form:<br />
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如上所述,量子系统的状态是由希尔伯特空间中的单位向量给出的。更一般地说,如果一个人对系统的了解较少,那么他就称之为“集合” ,并用密度矩阵来描述它,密度矩阵是正半定矩阵,或者当状态空间是无限维且迹1时,用迹类来描述它。同样的,在谱定理,这样的矩阵采取了一般的形式:<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to [[quantum teleportation]] and to [[superdense coding]], whereas non-locality is defined according to experimental statistics and is much more involved with the [[Quantum foundations|foundations]] and [[interpretations of quantum mechanics]].<ref>In the literature "non-locality" is sometimes used to characterize concepts that differ from the non-existence of a local hidden variable model, e.g., whether states can be distinguished by local measurements and which can occur also for non-entangled states (see, e.g., {{cite journal |authors=Charles H. Bennett, David P. DiVincenzo, Christopher A. Fuchs, Tal Mor, Eric Rains, Peter W. Shor, John A. Smolin, and William K. Wootters |title=Quantum nonlocality without entanglement |journal=Phys. Rev. A |volume=59 |issue=2 |pages=1070–1091 |year=1999 |doi=10.1103/PhysRevA.59.1070 |arxiv= quant-ph/9804053|bibcode=1999PhRvA..59.1070B |s2cid=15282650 }}). This non-standard use of the term is not discussed here.</ref><br />
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<math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
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我不知道,我不知道,我不知道<br />
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== Quantum mechanical framework ==<br />
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where the w<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret as representing an ensemble where is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need density matrices to represent the state.<br />
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其中 w < sub > i </sub > 是正值概率(和为1) ,向量是单位向量,在无限维情况下,我们取这些状态的闭包为迹范数。我们可以解释为代表一个集合,其中集合的状态是 < math > | alpha _ i rangle </math > 。当一个混合状态的秩为1时,它就描述了一个纯系综。当量子系统的状态信息少于总量时,我们需要密度矩阵来表示状态。<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of [[quantum mechanics]], including familiarity with the formalism and theoretical framework developed in the articles: [[bra–ket notation]] and [[mathematical formulation of quantum mechanics]].<br />
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Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits electrons towards an observer. The electrons' Hilbert spaces are identical. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with spins aligned in the positive direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
在实验上,可以实现如下的混合集成。考虑一个“黑盒子”装置,它向观察者喷射电子。电子的希尔伯特空间是相同的。该装置可能产生全部处于相同状态的电子; 在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以在不同的状态下产生电子。例如,它可以产生两个电子群: 一个是状态 < math > | mathbf { z } + rangle </math > 的正方向自旋,另一个是状态 < math > | mathbf { y }-rangle </math > 的负方向自旋。通常,这是一个混合集合,因为可以有任意数量的总体,每个总体对应不同的状态。<br />
<br />
=== Pure states ===<br />
<br />
Consider two arbitrary quantum systems {{mvar|A}} and {{mvar|B}}, with respective [[Hilbert space]]s {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}. The Hilbert space of the composite system is the [[tensor product]]<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on . That is, it has the general form<br />
<br />
根据上面的定义,对于二部复合系统,混合态仅仅是上面的密度矩阵。也就是说,它有一般的形式<br />
<br />
<br />
<br />
: <math> H_A \otimes H_B.</math><br />
<br />
<math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
[数学] rho = sum { i } w _ i 左[ sum _ { j } bar { c }{ ij }(| alpha _ { ij } rangle otimes | beta _ { ij } rangle)右]左[ sum _ k c _ { ik }(langle alpha _ ik } | otimes langle beta _ { ik } | 右]<br />
<br />
<br />
<br />
</math><br />
<br />
数学<br />
<br />
If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
<br />
<br />
<br />
where the w<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
其中 w < sub > i </sub > 是正值概率,< math > sum _ j | c _ { ij } | ^ 2 = 1 </math > ,向量是单位向量。这是自伴和正的,并且有迹1。<br />
<br />
: <math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<br />
<br />
从纯粹情形扩展可分性的定义,我们说混合状态是可分的,如果它可以写成<br />
<br />
States of the composite system that can be represented in this form are called [[separable state]]s, or [[product state]]s.<br />
<br />
<br />
<br />
<math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
(数学) rho = sum i w i rho i ^ a times rho i ^ b,(数学)<br />
<br />
Not all states are separable states (and thus product states). Fix a [[basis (linear algebra)|basis]] <math>\scriptstyle \{|i \rangle_A\}</math> for {{mvar|H<sub>A</sub>}} and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for {{mvar|H<sub>B</sub>}}. The most general state in {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} is of the form<br />
<br />
<br />
<br />
where the are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems and respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
其中的正值概率和 rho _ i ^ a </math > 的和 rho _ i ^ b </math > 的本身是子系统和子系统上的混合状态(密度算符)。换句话说,如果一个状态是不相关状态或乘积状态上的概率分布,则该状态是可分的。通过将密度矩阵写成纯系综和并进行扩展,我们可以假定,不失一般性和数学本身就是纯系综。如果一个状态不可分离,则称其为纠缠态。<br />
<br />
: <math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be NP-hard. For the and cases, a necessary and sufficient criterion for separability is given by the famous Positive Partial Transpose (PPT) condition.<br />
<br />
一般来说,要判断一个混合态是否是纠缠态是很困难的。一般的二部格被证明是 np 困难的。对于和种情形,利用著名的正偏转子(PPT)条件给出了可分性的一个充要条件。<br />
<br />
This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
<br />
<br />
<br />
For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of {{mvar|H<sub>A</sub>}} and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of {{mvar|H<sub>B</sub>}}, the following is an entangled state:<br />
<br />
The idea of a reduced density matrix was introduced by Paul Dirac in 1930. Consider as above systems and each with a Hilbert space . Let the state of the composite system be<br />
<br />
约化密度矩阵的概念是由保罗 · 狄拉克在1930年提出的。考虑以上系统,每个系统都有一个希尔伯特空间。设复合系统的状态为<br />
<br />
<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
<br />
<math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
[数学] | Psi 在 h _ a 和 h _ b 之间。数学<br />
<br />
<br />
<br />
If the composite system is in this state, it is impossible to attribute to either system {{mvar|A}} or system {{mvar|B}} a definite [[pure state]]. Another way to say this is that while the [[von Neumann entropy]] of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry.<ref name="JaegerEtAl95">{{cite journal |author=Jaeger G, Shimony A, Vaidman L |title=Two Interferometric Complementarities |journal=Phys. Rev. |volume=51 |issue=1 |pages=54–67 |year=1995 |doi=10.1103/PhysRevA.51.54|pmid=9911555 |bibcode = 1995PhRvA..51...54J |last2=Shimony |last3=Vaidman }}</ref> The above example is one of four [[Bell states]], which are (maximally) entangled pure states (pure states of the {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} space, but which cannot be separated into pure states of each {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}).<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system . However, it still is possible to associate a density matrix. Let<br />
<br />
如上所述,通常没有办法将纯状态关联到组件系统。然而,仍然有可能将密度矩阵联系起来。让<br />
<br />
<br />
<br />
Now suppose Alice is an observer for system {{mvar|A}}, and Bob is an observer for system {{mvar|B}}. If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of {{mvar|A}}, there are two possible outcomes, occurring with equal probability:<ref name=nielchuang>{{cite book| last = Nielsen | first = Michael A. |author2=Chuang, Isaac L. | year = 2000 | title = Quantum Computation and Quantum Information | publisher = [[Cambridge University Press]] | pages = 112–113| isbn = 978-0-521-63503-5}}</ref><br />
<br />
<math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
我不知道,我不知道,我不知道。<br />
<br />
<br />
<br />
# Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
<br />
which is the projection operator onto this state. The state of is the partial trace of over the basis of system :<br />
<br />
也就是这个状态的投影操作符。状态是系统基础上的部分轨迹:<br />
<br />
# Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
<br />
<br />
<br />
<math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
(| Psi rangle langle Psi | right) | j rangle b = hbox { Tr } _ b; rho _ t. </math > <br />
<br />
If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system {{mvar|B}} has been altered by Alice performing a local measurement on system {{mvar|A}}. This remains true even if the systems {{mvar|A}} and {{mvar|B}} are spatially separated. This is the foundation of the [[EPR paradox]].<br />
<br />
<br />
<br />
is sometimes called the reduced density matrix of on subsystem . Colloquially, we "trace out" system to obtain the reduced density matrix on .<br />
<br />
有时被称为子系统的约化密度矩阵。通俗地说,我们“追踪”系统,以获得约化密度矩阵。<br />
<br />
The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see [[no-communication theorem]].<br />
<br />
<br />
<br />
For example, the reduced density matrix of for the entangled state<br />
<br />
例如,纠缠态的约化密度矩阵<br />
<br />
=== Ensembles ===<br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a [[density matrix]], which is a [[positive-semidefinite matrix]], or a [[trace class]] when the state space is infinite-dimensional, and has trace 1. Again, by the [[spectral theorem]], such a matrix takes the general form:<br />
<br />
<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right) ,</math > <br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
discussed above is<br />
<br />
以上所讨论的是<br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors {{mvar| α<sub>i</sub>}} are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret {{mvar|ρ}} as representing an ensemble where {{mvar|w<sub>i</sub>}} is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need [[#Reduced density matrices|density matrices]] to represent the state.<br />
<br />
<math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
左(| 0 rangle 0 | a + | 1 rangle 1 | a right) </math > <br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits [[electron]]s towards an observer. The electrons' Hilbert spaces are [[identical particles|identical]]. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with [[spin (physics)|spins]] aligned in the positive {{math|'''z'''}} direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative {{math|'''y'''}} direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
这表明,正如预期的那样,一个纠缠纯系综的约化密度矩阵是一个混合系综。同样不足为奇的是,上面讨论的纯乘积态的密度矩阵<br />
<br />
<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}}. That is, it has the general form<br />
<br />
<math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
我不知道,但是我知道,我知道。<br />
<br />
<br />
<br />
: <math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
一般情况下,二体纯态 ρ 纠缠当且仅当其约化态是混合态而不是纯态。<br />
<br />
</math><br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional AKLT spin chain: the ground state can be divided into a block and an environment. The reduced density matrix of the block is proportional to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
在不同的基态自旋链中显式计算了约化密度矩阵。一维 AKLT 自旋链就是一个例子: 基态可以分为一个区块和一个环境。块的约化密度矩阵与另一个哈密顿量的简并基态成正比。<br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<ref name=Laloe>{{citation|last=Laloe|first=Franck|year=2001|title=Do We Really Understand Quantum Mechanics|journal=American Journal of Physics |volume=69 |issue=6|pages=655–701 |arxiv=quant-ph/0209123 |bibcode=2001AmJPh..69..655L |doi=10.1119/1.1356698}}</ref>{{rp|131–132}}<br />
<br />
The reduced density matrix also was evaluated for XY spin chains, where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence in this case.<br />
<br />
并对 XY 自旋链的全秩约化密度矩阵进行了计算。证明了在热力学极限中,大块自旋的约化密度矩阵的谱在这种情况下是一个精确的几何序列。<br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary quantum operations can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called LOCC (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<br />
<br />
在量子信息理论中,纠缠态被认为是一种“资源” ,即制造成本高昂的物质,并且可以实现有价值的转换。这种观点最为明显的背景是“遥远的实验室” ,即两个标记为“ a”和“ b”的量子系统,其中每个系统都可以执行任意的量子操作,但它们之间不存在量子力学相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为 LOCC 的操作(局部操作和经典通信)。这些操作不允许在系统 a 和系统 b 之间产生纠缠态。但是如果给 a 和 b 提供了纠缠态,那么这些纠缠态和 LOCC 操作一起可以产生更大类的变换。例如,a 的一个量子比特和 b 的一个量子比特之间的相互作用可以通过首先将 a 的量子比特传送到 b,然后让 b 的量子比特和 b 的量子比特相互作用(这现在是一个 LOCC 操作,因为两个量子比特都在 b 的实验室里) ,然后再传送量子比特回到 a。两个量子比特的最大纠缠态在这个过程中被用完。因此,纠缠态是一种资源,它能够在只有 LOCC 可用的情况下实现量子相互作用(或量子通道) ,但是在这个过程中会被消耗掉。在其他应用中,纠缠态可以被看作是一种资源,例如,私人通信或者区分量子态。<br />
<br />
where the {{mvar|w<sub>i</sub>}} are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems {{mvar|A}} and {{mvar|B}} respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be [[NP-hard]].<ref>{{Cite book |author=Gurvits L |title=Proceedings of the thirty-fifth ACM symposium on Theory of computing - STOC '03 |chapter=Classical deterministic complexity of Edmonds' Problem and quantum entanglement |journal=Proceedings of the Thirty-fifth Annual ACM Symposium on Theory of Computing |year=2003 |doi=10.1145/780542.780545 |page=10 |isbn=978-1-58113-674-6|arxiv=quant-ph/0303055 |s2cid=5745067 }}</ref> For the {{math|2 × 2}} and {{math|2 × 3}} cases, a necessary and sufficient criterion for separability is given by the famous [[Peres-Horodecki criterion|Positive Partial Transpose (PPT)]] condition.<ref>{{cite journal |author=Horodecki M, Horodecki P, Horodecki R |title=Separability of mixed states: necessary and sufficient conditions |journal=Physics Letters A |volume=223 |issue=1 |page=210 |year=1996 |doi=10.1016/S0375-9601(96)00706-2 |bibcode=1996PhLA..223....1H|arxiv = quant-ph/9605038 |last2=Horodecki |last3=Horodecki |citeseerx=10.1.1.252.496 |s2cid=10580997 }}</ref><br />
<br />
<br />
<br />
=== Reduced density matrices ===<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
<br />
在这一节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的度量。<br />
<br />
The idea of a reduced density matrix was introduced by [[Paul Dirac]] in 1930.<ref>{{cite journal|doi=10.1017/S0305004100016108|title=Note on Exchange Phenomena in the Thomas Atom|year=2008|last1=Dirac|first1=P. A. M.|journal=Mathematical Proceedings of the Cambridge Philosophical Society| volume=26| issue=3|page=376|bibcode=1930PCPS...26..376D|url=https://www.cambridge.org/core/services/aop-cambridge-core/content/view/6C5FF7297CD96F49A8B8E9E3EA50E412/S0305004100016108a.pdf/div-class-title-note-on-exchange-phenomena-in-the-thomas-atom-div.pdf}}</ref> Consider as above systems {{mvar|A}} and {{mvar|B}} each with a Hilbert space {{mvar|H<sub>A</sub>, H<sub>B</sub>}}. Let the state of the composite system be<br />
<br />
<br />
<br />
: <math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.<br />
<br />
二分子2能级纯态的冯纽曼熵与本征值的图。当本征值为5时,冯纽曼熵处于最大值,相当于最大纠缠度。<br />
<br />
<br />
<br />
In classical information theory , the Shannon entropy, is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<br />
<br />
在经典的信息论中,香农熵,是与概率分布相关联的,如下:<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system {{mvar|A}}. However, it still is possible to associate a density matrix. Let<br />
<br />
<br />
<br />
<math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
<br />
[ math ] h (p _ 1,cdots,p _ n) =-sum _ i p _ i log _ 2 p _ i. [ math ]<br />
<br />
: <math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
<br />
<br />
Since a mixed state is a probability distribution over an ensemble, this leads naturally to the definition of the von Neumann entropy:<br />
<br />
由于混合状态是一个概率分布超过一个总体,这自然导致了冯纽曼熵的定义:<br />
<br />
which is the [[projection operator]] onto this state. The state of {{mvar|A}} is the [[partial trace]] of {{mvar|ρ<sub>T</sub>}} over the basis of system {{mvar|B}}:<br />
<br />
<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
<br />
(rho) =-hbox { Tr } left (rho log _ 2{ rho } right) <br />
<br />
: <math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
<br />
<br />
In general, one uses the Borel functional calculus to calculate a non-polynomial function such as . If the nonnegative operator acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
<br />
一般来说,人们使用 Borel 函数演算来计算一个非多项式函数,如。如果非负算子作用于有限维希尔伯特空间,并且具有本征值 < math > lambda _ 1,那么 cdots,lambda _ n </math > ,结果只不过是具有相同本征向量的算子,但本征值 < math > log _ 2(lambda _ 1) ,点,log _ 2(lambda _ n) </math > 。那么香农熵就是:<br />
<br />
{{mvar|ρ<sub>A</sub>}} is sometimes called the reduced density matrix of {{mvar|ρ}} on subsystem {{mvar|A}}. Colloquially, we "trace out" system {{mvar|B}} to obtain the reduced density matrix on {{mvar|A}}.<br />
<br />
<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
<br />
(rho) =-hbox { Tr } left (rho log 2{ rho } right) =-sum _ i lambda _ i log _ 2 lambda _ i </math > .<br />
<br />
For example, the reduced density matrix of {{mvar|A}} for the entangled state<br />
<br />
<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
<br />
因为一个概率为0的事件不应该对熵有贡献,并且假设<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
<br />
<br />
<math> \lim_{p \to 0} p \log p = 0,</math><br />
<br />
[ math > lim _ { p to 0} p log p = 0,</math > <br />
<br />
discussed above is<br />
<br />
<br />
<br />
the convention 0}} is adopted. This extends to the infinite-dimensional case as well: if has spectral resolution<br />
<br />
约定0}被采用。这也延伸到无限维情况: 如果有光谱分辨率<br />
<br />
: <math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
<br />
<br />
<math> \rho = \int \lambda d P_{\lambda},</math><br />
<br />
数学,数学,数学<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of {{mvar|A}} for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
<br />
<br />
assume the same convention when calculating<br />
<br />
在计算时采用相同的约定<br />
<br />
: <math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
<br />
<br />
<math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
<br />
[数学] rho log 2 rho = int lambda log 2 lambda d { lambda }<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
<br />
<br />
As in statistical mechanics, the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is (which can be shown to be the maximum entropy for mixed states).<br />
<br />
就像统计力学一样,系统的不确定性(微观状态的数量)越多,熵就越大。例如,任何纯态的熵都为零,这并不奇怪,因为处于纯态的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个的熵都是(混合态的最大熵)。<br />
<br />
=== Two applications that use them ===<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional [[AKLT Model|AKLT spin chain]]:<ref name="Fan2004">{{cite journal | doi = 10.1103/PhysRevLett.93.227203 | title = Entanglement in a Valence-Bond Solid State | journal = Physical Review Letters | year = 2004 | first = H | last = Fan | page = 227203 |author2=Korepin V |author3=Roychowdhury V | volume = 93 | issue = 22 | pmid = 15601113 |arxiv=quant-ph/0406067 | bibcode=2004PhRvL..93v7203F| s2cid = 28587190 }}</ref> the ground state can be divided into a block and an environment. The reduced density matrix of the block is [[Proportionality (mathematics)|proportional]] to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist. If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
<br />
熵提供了一个可以用来量化纠缠的工具,尽管还存在其他的纠缠度量方法。如果整个系统是纯系统,则可以用一个子系统的熵来衡量其与其他子系统的纠缠程度。<br />
<br />
The reduced density matrix also was evaluated for [[Heisenberg model (quantum)|XY spin chains]], where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence<ref>{{cite journal| doi=10.1007/s11128-010-0197-7|arxiv=1002.2931|title=Spectrum of the density matrix of a large ''block of'' spins of the XY model in one dimension| year=2010|last1=Franchini|first1=F.|last2=Its|first2=A. R.|last3=Korepin|first3=V. E.|last4=Takhtajan|first4=L. A.|journal=Quantum Information Processing|volume=10|issue=3|pages=325–341|s2cid=6683370}}</ref> in this case.<br />
<br />
<br />
<br />
For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
<br />
对于两体纯态,减少态的冯纽曼熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的特定公理的态家族中唯一的函数。<br />
<br />
=== Entanglement as a resource ===<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary [[quantum operation]]s can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called [[LOCC]] (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<ref name="horodecki2007" /><br />
<br />
It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/n,...,1/n}. Therefore, a bipartite pure state is said to be a maximally entangled state if the reduced state of is the diagonal matrix<br />
<br />
一个经典的结果是,香农熵在均匀概率分布{1/n,... ,1/n }处达到最大值。因此,如果二分纯态的约化态是对角矩阵,则称二分纯态为最大纠缠态<br />
<br />
<br />
<br />
=== Classification of entanglement ===<br />
<br />
<math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
<br />
< math > begin { bmatrix } frac {1}{ n } & & ddots & frac {1}{ n } end { bmatrix } . </math > <br />
<br />
Not all quantum states are equally valuable as a resource. To quantify this value, different [[Quantum entanglement#Entanglement measures|entanglement measures]] (see below) can be used, that assign a numerical value to each quantum state. However, it is often interesting to settle for a coarser way to compare quantum states. This gives rise to different classification schemes. Most entanglement classes are defined based on whether states can be converted to other states using LOCC or a subclass of these operations. The smaller the set of allowed operations, the finer the classification. Important examples are:<br />
<br />
* If two states can be transformed into each other by a local unitary operation, they are said to be in the same ''LU class''. This is the finest of the usually considered classes. Two states in the same LU class have the same value for entanglement measures and the same value as a resource in the distant-labs setting. There is an infinite number of different LU classes (even in the simplest case of two qubits in a pure state).<ref name="GRB1998">>{{cite journal |author1=Grassl, M. |author2=Rötteler, M. |author3=Beth, T. |title=Computing local invariants of quantum-bit systems |journal=Phys. Rev. A |volume=58 |issue=3 |pages=1833–1839 |year=1998 |doi=10.1103/PhysRevA.58.1833 |arxiv=quant-ph/9712040|bibcode=1998PhRvA..58.1833G |s2cid=15892529 }}</ref><ref name="Kraus2010">{{cite journal |author=B. Kraus |authorlink=Barbara Kraus|title=Local unitary equivalence of multipartite pure states |journal=Phys. Rev. Lett. |volume=104 |issue=2 |page=020504 |year=2010 |arxiv=0909.5152 |doi=10.1103/PhysRevLett.104.020504|pmid=20366579 |bibcode=2010PhRvL.104b0504K|s2cid=29984499}}</ref><br />
<br />
For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
<br />
对于混合态,简化冯纽曼熵并不是唯一合理的纠缠度量。<br />
<br />
* If two states can be transformed into each other by local operations including measurements with probability larger than 0, they are said to be in the same 'SLOCC class' ("stochastic LOCC"). Qualitatively, two states <math>\rho_1</math> and <math>\rho_2</math> in the same SLOCC class are equally powerful (since I can transform one into the other and then do whatever it allows me to do), but since the transformations <math>\rho_1\to\rho_2</math> and <math>\rho_2\to\rho_1</math> may succeed with different probability, they are no longer equally valuable. E.g., for two pure qubits there are only two SLOCC classes: the entangled states (which contains both the (maximally entangled) Bell states and weakly entangled states like <math>|00\rangle+0.01|11\rangle</math>) and the separable ones (i.e., product states like <math>|00\rangle</math>).<ref>{{cite journal |author=M. A. Nielsen |title=Conditions for a Class of Entanglement Transformations |journal=Phys. Rev. Lett. |volume=83 |issue=2 |page=436 |year=1999 |doi=10.1103/PhysRevLett.83.436 |arxiv=quant-ph/9811053|bibcode=1999PhRvL..83..436N |s2cid=17928003 }}</ref><ref name="GoWa2010">{{cite journal |authors=Gour, G. & Wallach, N. R. |title=Classification of Multipartite Entanglement of All Finite Dimensionality |journal=Phys. Rev. Lett. |volume=111 |issue=6 |page=060502 |year=2013 |doi=10.1103/PhysRevLett.111.060502 |pmid=23971544 |arxiv=1304.7259|bibcode=2013PhRvL.111f0502G |s2cid=1570745 }}</ref><br />
<br />
* Instead of considering transformations of single copies of a state (like <math>\rho_1\to\rho_2</math>) one can define classes based on the possibility of multi-copy transformations. E.g., there are examples when <math>\rho_1\to\rho_2</math> is impossible by LOCC, but <math>\rho_1\otimes\rho_1\to\rho_2</math> is possible. A very important (and very coarse) classification is based on the property whether it is possible to transform an arbitrarily large number of copies of a state <math>\rho</math> into at least one pure entangled state. States that have this property are called [[Entanglement distillation|distillable]]. These states are the most useful quantum states since, given enough of them, they can be transformed (with local operations) into any entangled state and hence allow for all possible uses. It came initially as a surprise that not all entangled states are distillable, those that are not are called '[[Bound entanglement|bound entangled]]'.<ref name="HHH97">{{cite journal |author1=Horodecki, M. |author2=Horodecki, P. |author3=Horodecki, R. |title=Mixed-state entanglement and distillation: Is there a ''bound'' entanglement in nature? |journal=Phys. Rev. Lett. |volume=80 |issue=1998 |pages=5239–5242 |year=1998 |arxiv=quant-ph/9801069|doi=10.1103/PhysRevLett.80.5239 |bibcode=1998PhRvL..80.5239H |s2cid=111379972 }}</ref><ref name="horodecki2007" /><br />
<br />
As an aside, the information-theoretic definition is closely related to entropy in the sense of statistical mechanics (comparing the two definitions in the present context, it is customary to set the Boltzmann constant 1}}). For example, by properties of the Borel functional calculus, we see that for any unitary operator ,<br />
<br />
顺便说一句,信息论的定义与统计力学意义上的熵密切相关(比较在当前语境下的两个定义,通常设置波兹曼常数1})。例如,通过 Borel 泛函微积分的性质,我们可以看到,对于任何幺正算符,<br />
<br />
<br />
<br />
A different entanglement classification is based on what the quantum correlations present in a state allow A and B to do: one distinguishes three subsets of entangled states: (1) the ''[[Quantum nonlocality|non-local]] states'', which produce correlations that cannot be explained by a local hidden variable model and thus violate a Bell inequality, (2) the ''[[Quantum steering|steerable]] states'' that contain sufficient correlations for A to modify ("steer") by local measurements the conditional reduced state of B in such a way, that A can prove to B that the state they possess is indeed entangled, and finally (3) those entangled states that are neither non-local nor steerable. All three sets are non-empty.<ref name="WJD2007">{{cite journal |title=Steering, Entanglement, Nonlocality, and the Einstein-Podolsky-Rosen Paradox |authors=H. M. Wiseman, S. J. Jones, and A. C. Doherty |journal=Phys. Rev. Lett. |volume=98 |issue=14 |page=140402 |year=2007 |doi=10.1103/PhysRevLett.98.140402 |pmid=17501251 |arxiv=quant-ph/0612147|bibcode=2007PhRvL..98n0402W |s2cid=30078867 }}</ref><br />
<br />
<math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
s (rho) = s left (u rho u ^ * right) . </math > <br />
<br />
<br />
<br />
=== Entropy ===<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
<br />
事实上,如果没有这个属性,冯纽曼熵就不会有明确的定义。<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
<br />
<br />
<br />
In particular, could be the time evolution operator of the system, i.e.,<br />
<br />
特别是,可以是系统的时间演化算子,即,<br />
<br />
==== Definition ====<br />
<br />
[[File:Von Neumann entropy for bipartite system plot.svg|right|thumb|200px|The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.]]<br />
<br />
<math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
<br />
[ math ] u (t) = exp left (frac {-i h t }{ hbar } right) ,[ math ]<br />
<br />
In classical [[information theory]] {{mvar|H}}, the [[Shannon entropy]], is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<ref name="SE">{{cite web |url=http://authors.library.caltech.edu/5516/1/CERpra97b.pdf#page=10 |title=Information-theoretic interpretation of quantum error-correcting codes |first1=Nicolas J. |last1=Cerf |first2=Richard |last2=Cleve }}</ref><br />
<br />
<br />
<br />
where is the Hamiltonian of the system. Here the entropy is unchanged.<br />
<br />
这个系统的哈密顿量在哪里。这里熵不变。<br />
<br />
: <math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
<br />
<br />
<br />
The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the arrow of time towards thermodynamic equilibrium is simply the growing spread of quantum entanglement.<br />
<br />
一个过程的可逆性与由此产生的熵变有关,也就是说,一个过程是可逆的,当且仅当它使系统的熵不变。因此,时间之箭向热力学平衡的前进只不过是量子纠缠的蔓延。<br />
<br />
Since a mixed state {{mvar|ρ}} is a probability distribution over an ensemble, this leads naturally to the definition of the [[von Neumann entropy]]:<br />
<br />
This provides a connection between quantum information theory and thermodynamics.<br />
<br />
这提供了量子信息理论和热力学之间的联系。<br />
<br />
<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
<br />
Rényi entropy also can be used as a measure of entanglement.<br />
<br />
熵也可以用来度量纠缠。<br />
<br />
<br />
<br />
In general, one uses the [[Borel functional calculus]] to calculate a non-polynomial function such as {{math|log<sub>2</sub>(''ρ'')}}. If the nonnegative operator {{mvar|ρ}} acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, {{math|log<sub>2</sub>(''ρ'')}} turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
<br />
<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, entanglement entropy is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<br />
<br />
量子纠缠度量了量子态(通常被视为双体)中纠缠的数量。如前所述,纠缠熵是纯态的标准量度(但不再是混合态的量度)。对于混合态,文献中有一些纠缠度量<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
<br />
<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
<br />
The Reeh-Schlieder theorem of quantum field theory is sometimes seen as an analogue of quantum entanglement.<br />
<br />
量子场论的 Reeh-Schlieder 定理有时被看作是量子纠缠的类比。<br />
<br />
<br />
<br />
:<math> \lim_{p \to 0} p \log p = 0,</math><br />
<br />
<br />
<br />
the convention {{math|0 log(0) {{=}} 0}} is adopted. This extends to the infinite-dimensional case as well: if {{mvar|ρ}} has [[projection-valued measure|spectral resolution]]<br />
<br />
Entanglement has many applications in quantum information theory. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
<br />
纠缠态在量子信息理论中有许多应用。在纠缠的帮助下,否则不可能完成的任务就可能实现。<br />
<br />
<br />
<br />
: <math> \rho = \int \lambda d P_{\lambda},</math><br />
<br />
Among the best-known applications of entanglement are superdense coding and quantum teleportation.<br />
<br />
其中最著名的应用是超稠密编码和量子遥传纠缠。<br />
<br />
<br />
<br />
assume the same convention when calculating<br />
<br />
Most researchers believe that entanglement is necessary to realize quantum computing (although this is disputed by some).<br />
<br />
大多数研究人员认为量子纠缠对于实现量子计算是必要的(尽管有些人对此有争议)。<br />
<br />
<br />
<br />
: <math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
<br />
Entanglement is used in some protocols of quantum cryptography. This is because the "shared noise" of entanglement makes for an excellent one-time pad. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.<br />
<br />
纠缠被用于量子密码学的一些协议中。这是因为纠缠的“共享噪音”造就了绝佳的一次性衬垫。此外,由于测量纠缠对的任何一个成员都会破坏它们共享的纠缠,基于纠缠的量子密码学可以让发送方和接收方更容易地检测到拦截器的存在。<br />
<br />
<br />
<br />
As in [[entropy|statistical mechanics]], the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is {{math|log(2)}} (which can be shown to be the maximum entropy for {{math|2 × 2}} mixed states).<br />
<br />
In interferometry, entanglement is necessary for surpassing the standard quantum limit and achieving the Heisenberg limit.<br />
<br />
在干涉术中,纠缠态对于超越标准量子极限和达到海森堡极限是必要的。<br />
<br />
<br />
<br />
==== As a measure of entanglement ====<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist.<ref name="arxiv.org">{{cite journal|author1=Plenio|title=An introduction to entanglement measures|year=2007|pages=1–51|volume=1|journal=Quant. Inf. Comp. |arxiv=quant-ph/0504163|bibcode=2005quant.ph..4163P|last2=Virmani}}</ref> If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
<br />
在理论和实验中经常会出现几种典型的纠缠态。<br />
<br />
<br />
<br />
For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
<br />
For two qubits, the Bell states are<br />
<br />
对于两个量子比特,贝尔态是<br />
<br />
<br />
<br />
It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/''n'',...,1/''n''}. Therefore, a bipartite pure state {{math|''ρ'' ∈ ''H''<sub>A</sub> ⊗ ''H''<sub>B</sub>}} is said to be a '''maximally entangled state''' if the reduced state{{clarify|reason=To which system, A or B, or perhaps both?|date=May 2015}} of {{mvar|ρ}} is the diagonal matrix<br />
<br />
<math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
<br />
< math > | Phi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 0 rangle _ b | 1 rangle _ a o times | 1 rangle _ b) </math > <br />
<br />
<br />
<br />
<math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
<br />
< math > | Psi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 1 rangle _ b pm | 1 rangle _ a o times | 0 rangle _ b) </math > .<br />
<br />
: <math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
<br />
<br />
<br />
These four pure states are all maximally entangled (according to the entropy of entanglement) and form an orthonormal basis (linear algebra) of the Hilbert space of the two qubits. They play a fundamental role in Bell's theorem.<br />
<br />
这四个纯态都是最大纠缠态(根据纠缠熵) ,并且形成了两个量子位的希尔伯特空间的标准正交基(线性代数)。它们在贝尔定理中起着基本的作用。<br />
<br />
For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
<br />
<br />
<br />
For M>2 qubits, the GHZ state is<br />
<br />
对于 m > 2量子位,GHZ 态是<br />
<br />
As an aside, the information-theoretic definition is closely related to [[entropy (statistical views)|entropy]] in the sense of statistical mechanics{{Citation needed|date=January 2009}} (comparing the two definitions in the present context, it is customary to set the [[Boltzmann constant]] {{math|''k'' {{=}} 1}}). For example, by properties of the [[Borel functional calculus]], we see that for any [[unitary operator]] {{mvar|U}},<br />
<br />
<br />
<br />
<math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
<br />
< math > | mathrm { GHZ } rangle = frac { | 0 rangle ^ { otimes m } + | 1 rangle ^ { otimes m }{ sqrt {2} ,</math > <br />
<br />
: <math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
<br />
<br />
which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to qudits, i.e., systems of d rather than 2 dimensions.<br />
<br />
它缩小到贝尔状态。传统的 GHZ 状态定义为 < math > m = 3 </math > 。GHZ 状态偶尔会扩展到 qudit,即 d 而不是2维系统。<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
<br />
<br />
<br />
Also for M>2 qubits, there are spin squeezed states. Spin squeezed states are a class of squeezed coherent states satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled. Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<br />
<br />
对于 m > 2量子位,也存在自旋压缩态。自旋压缩态是一类对自旋测量不确定度满足一定限制的压缩相干态,它必然是纠缠态。自旋压缩态是利用量子纠缠增强精密测量的理想候选态。<br />
<br />
In particular, {{mvar|U}} could be the time evolution operator of the system, i.e.,<br />
<br />
<br />
<br />
For two bosonic modes, a NOON state is<br />
<br />
对于两个玻色模态,NOON 状态是<br />
<br />
: <math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
<br />
<br />
<br />
<math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
<br />
[数学] | psi _ text { NOON } rangle = frac { | n rangle _ a | 0 rangle _ b + | {0} rangle _ a | { n } rangle _ b }{ sqrt {2} ,,</math > <br />
<br />
where {{mvar|H}} is the [[Hamiltonian (quantum mechanics)|Hamiltonian]] of the system. Here the entropy is unchanged.<br />
<br />
<br />
<br />
This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the N photons are in one mode" and "the N photons are in the other mode".<br />
<br />
这就像贝尔态 < math > | Psi ^ + rangle </math > 除了基函数0和1已经被“ n 个光子处于一种模式”和“ n 个光子处于另一种模式”所取代。<br />
<br />
The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the [[arrow of time]] towards [[thermodynamic equilibrium]] is simply the growing spread of quantum entanglement.<ref>{{cite news |url=https://www.wired.com/2014/04/quantum-theory-flow-time/ |title=New Quantum Theory Could Explain the Flow of Time |last1=Wolchover |first1=Natalie |date=25 April 2014 |website=www.wired.com |publisher=Quanta Magazine |accessdate=27 April 2014}}</ref><br />
<br />
This provides a connection between [[quantum information theory]] and [[thermodynamics]].<br />
<br />
Finally, there also exist twin Fock states for bosonic modes, which can be created by feeding a Fock state into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<br />
<br />
最后,还存在玻色子模式的双 Fock 态,它可以通过将 Fock 态输入到两个导致分束器的臂来产生。它们是 NOON 态的倍数之和,可以用来实现海森堡极限。<br />
<br />
<br />
<br />
[[Rényi entropy]] also can be used as a measure of entanglement.<br />
<br />
For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
<br />
对于适当选择的纠缠度量,Bell、 GHZ 和 NOON 态是最大纠缠态,而自旋压缩态和双 Fock 态只是部分纠缠。部分纠缠态通常更容易在实验上准备。<br />
<br />
<br />
<br />
=== Entanglement measures ===<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, [[entropy of entanglement|entanglement entropy]] is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<ref name="arxiv.org" /> and no single one is standard.<br />
<br />
Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is spontaneous parametric down-conversion to generate a pair of photons entangled in polarisation. Other methods include the use of a fiber coupler to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a quantum dot, the use of the Hong–Ou–Mandel effect, etc., In the earliest tests of Bell's theorem, the entangled particles were generated using atomic cascades.<br />
<br />
纠缠通常是由亚原子粒子间的直接相互作用产生的。这些相互作用可以有多种形式。最常用的方法之一是用自发参量下转换产生一对纠缠在偏振中的光子。其他方法包括使用光纤耦合器来限制和混合光子,量子点中双激子衰变级联发射的光子,Hong-Ou-Mandel 效应的使用等等。在贝尔定理最早的测试中,纠缠粒子是利用原子级联产生的。<br />
<br />
* Entanglement cost<br />
<br />
* [[entanglement distillation|Distillable entanglement]]<br />
<br />
It is also possible to create entanglement between quantum systems that never directly interacted, through the use of entanglement swapping. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<br />
<br />
通过使用纠缠交换,也有可能在不直接相互作用的量子系统之间创造纠缠。如果它们的波函数在空间上仅仅重叠,至少是部分重叠,那么它们也可以相互纠缠全同粒子。<br />
<br />
* Entanglement of formation<br />
<br />
* [[quantum relative entropy|Relative entropy of entanglement]]<br />
<br />
* [[Squashed entanglement]]<br />
<br />
* [[Logarithmic negativity]]<br />
<br />
A density matrix ρ is called separable if it can be written as a convex sum of product states, namely<br />
<br />
密度矩阵 ρ 称为可分的,如果它可以写成乘积态的凸和,即<br />
<br />
Most (but not all) of these entanglement measures reduce for pure states to entanglement entropy, and are difficult ([[NP-hard]]) to compute.<ref>{{cite journal|last1=Huang|first1=Yichen|title=Computing quantum discord is NP-complete|journal=New Journal of Physics|date=21 March 2014|volume=16|issue=3|pages=033027|doi=10.1088/1367-2630/16/3/033027|bibcode=2014NJPh...16c3027H|arxiv = 1305.5941 |s2cid=118556793}}</ref><br />
<br />
<br />
<br />
<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
<br />
显示方式{ rho = sum _ j p _ j rho _ j ^ {(a)}次 rho _ j ^ {(b)}} </math > <br />
<br />
=== Quantum field theory ===<br />
<br />
The [[Reeh-Schlieder theorem]] of [[quantum field theory]] is sometimes seen as an analogue of quantum entanglement.<br />
<br />
with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
<br />
概率为1 ge p _ j ge 0 </math > 。根据定义,如果一个态不可分离,它就是纠缠态。<br />
<br />
<br />
<br />
== Applications ==<br />
<br />
For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple Peres–Horodecki criterion provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes NP-hard when generalized. Other separability criteria include (but not limited to) the range criterion, reduction criterion, and those based on uncertainty relations. See Ref. for a review of separability criteria in discrete variable systems.<br />
<br />
对于2量子比特和2 × 2量子比特-量子特里特系统(分别为2 × 2和2 × 3) ,简单的 Peres-horowitz 准则为分离提供了一个必要和充分的判据,从而无意识地提供了检测纠缠的判据。然而,对于一般情形,该判据仅仅是可分性的必要条件,因为问题一经推广就变成了 np 难问题。其他可分性标准包括(但不限于)范围标准、归约标准和基于不确定关系的标准。参见参考文献。回顾了离散变量系统的可分性准则。<br />
<br />
<br />
<br />
Entanglement has many applications in [[quantum information theory]]. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
<br />
A numerical approach to the problem is suggested by Jon Magne Leinaas, Jan Myrheim and Eirik Ovrum in their paper "Geometrical aspects of entanglement". Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in Peres-Horodecki criterion testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
<br />
Jon Magne Leinaas,Jan Myrheim 和 Eirik Ovrum 在他们的论文“纠缠的几何方面”中提出了一个数值方法来解决这个问题。莱纳斯等。提供一个数值方法,迭代精炼一个估计的可分离状态朝向要测试的目标状态,并检查目标状态是否确实能够到达。该算法的一个实现(包括内置的 peres-horowitz 标准测试)是[ StateSeparator http://phweb.technion.ac.il/~StateSeparator/] web-app。<br />
<br />
<br />
<br />
Among the best-known applications of entanglement are [[superdense coding]] and [[quantum teleportation]].<ref>{{cite journal |last1=Bouwmeester |first1=Dik |last2=Pan |first2=Jian-Wei|last3=Mattle |first3=Klaus|last4=Eibl |first4=Manfred |last5=Weinfurter |first5=Harald|last6=Zeilinger |first6=Anton|year=1997 |title=Experimental Quantum Teleportation |journal=Nature |volume=390 |issue=6660 |pages=575–579 |name-list-style=amp |url=http://qudev.ethz.ch/content/courses/QSIT06/pdfs/Bouwmeester97.pdf |doi=10.1038/37539|bibcode = 1997Natur.390..575B |arxiv=1901.11004 |s2cid=4422887 }}</ref><br />
<br />
In continuous variable systems, the Peres-Horodecki criterion also applies. Specifically, Simon formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref. for a seemingly different but essentially equivalent approach). It was later found that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators or by using entropic measures.<br />
<br />
在连续变量系统中,Peres-Horodecki 准则也适用。具体地说,Simon 根据正则算符的二阶矩,制定了 Peres-Horodecki 准则的一个特定版本,并表明它对于 < math > 1 oplus1 </math >-mode Gaussian 状态是必要的和充分的。看似不同,但本质上等价的方法)。后来发现,Simon 的条件对于 < math > 1 oplus n </math >-mode Gaussian 状态也是必要和充分的,但是对于 < math > 2 oplus2 </math >-mode Gaussian 状态不再是充分的。Simon 条件可以通过考虑正则算子的高阶矩或者用熵测度来推广。<br />
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<br />
<br />
Most researchers believe that entanglement is necessary to realize [[quantum computer|quantum computing]] (although this is disputed by some).<ref name="jozsa02">{{cite journal|author1=Richard Jozsa|author2=Noah Linden|doi=10.1098/rspa.2002.1097|title=On the role of entanglement in quantum computational speed-up|year=2002|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=459|issue=2036|pages=2011–2032|arxiv=quant-ph/0201143|bibcode = 2003RSPSA.459.2011J |citeseerx=10.1.1.251.7637|s2cid=15470259}}</ref><br />
<br />
In 2016 China launched the world’s first quantum communications satellite. The $100m Quantum Experiments at Space Scale (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
<br />
2016年,中国发射了世界上第一颗量子通信卫星。耗资1亿美元的空间量子实验任务于2016年8月16日当地时间01:40从中国北方的酒泉卫星发射中心空间站发射升空。<br />
<br />
<br />
<br />
Entanglement is used in some protocols of [[quantum cryptography]].<ref name="ekert91">{{cite journal |doi=10.1103/PhysRevLett.67.661 |title=Quantum cryptography based on Bell's theorem |year=1991 |last1=Ekert |first1=Artur K. |journal=Physical Review Letters |volume=67 |issue=6 |pages=661–663 |pmid=10044956|bibcode = 1991PhRvL..67..661E |s2cid=27683254 |url=http://pdfs.semanticscholar.org/f8dc/c3047eef8da135bca13b926b1e6cf50e7f3a.pdf }}</ref><ref name="horodecki10">{{cite arXiv |eprint=1006.0468|last1=Yin|first1=Juan|title=Contextuality offers device-independent security|last2=Cao|first2=Yuan|last3=Yong|first3=Hai-Lin|last4=Ren|first4=Ji-Gang|last5=Liang|first5=Hao|last6=Liao|first6=Sheng-Kai|last7=Zhou|first7=Fei|last8=Liu|first8=Chang|last9=Wu|first9=Yu-Ping|last10=Pan|first10=Ge-Sheng|last11=Zhang|first11=Qiang|last12=Peng|first12=Cheng-Zhi|last13=Pan|first13=Jian-Wei|class=quant-ph|year=2010}}</ref> This is because the "shared noise" of entanglement makes for an excellent [[one-time pad]]. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.{{citation needed|date=January 2018}}<br />
<br />
For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
<br />
在接下来的两年里,这艘以中国古代哲学家墨子命名的飞船将展示量子化的可行性<br />
<br />
<br />
<br />
communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
<br />
地球和太空之间的通信,并在前所未有的距离上测试量子纠缠。<br />
<br />
In [[interferometry]], entanglement is necessary for surpassing the [[standard quantum limit]] and achieving the [[Heisenberg limit]].<ref>{{cite journal |last1=Pezze |first1=Luca |last2=Smerzi |first2=Augusto|year=2009 |title=Entanglement, Nonlinear Dynamics, and the Heisenberg Limit |journal=Phys. Rev. Lett. |volume=102 |issue=10 |pages=100401 |name-list-style=amp |doi=10.1103/PhysRevLett.102.100401 |pmid=19392092 |bibcode=2009PhRvL.102j0401P|arxiv = 0711.4840 |s2cid=13095638 }}</ref><br />
<br />
<br />
<br />
In the June 16, 2017, issue of Science, Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<br />
<br />
在2017年6月16日的《科学》杂志上。在严格的爱因斯坦定域条件下,从墨丘利卫星到 Lijian、云南和 Delingha、 Quinhai 的基地的 CHSH 估值为2.37 ± 0.09,证明了双光子对的存在和对 Bell 不等式的违反,从而提高了数量级通过光纤实验的传输效率。<br />
<br />
=== Entangled states ===<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
<br />
<br />
<br />
For two [[qubits]], the [[Bell state]]s are<br />
<br />
The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be calculated only by consideration of electron entanglement.<br />
<br />
多电子原子的电子壳层总是由纠缠电子组成。只有考虑到电子纠缠,才能计算出正确的电离能。<br />
<br />
<br />
<br />
: <math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
<br />
: <math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
<br />
<br />
<br />
It has been suggested that in the process of photosynthesis, entanglement is involved in the transfer of energy between light-harvesting complexes and photosynthetic reaction centers where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using femtosecond spectroscopy, the coherence of entanglement in the Fenna-Matthews-Olson complex was measured over hundreds of femtoseconds (a relatively long time in this regard) providing support to this theory.<br />
<br />
研究表明,在光合作用过程中,纠缠参与了捕光复合物与光合反应中心之间的能量传递,而光(能)是以化学能的形式获得的。没有这样一个过程,光转化为化学能的有效性就无从解释。利用飞秒光谱技术,我们测量了 Fenna-Matthews-Olson 复合体中纠缠态的相干性,时间长达数百飞秒,为这一理论提供了支持。<br />
<br />
These four pure states are all maximally entangled (according to the [[entropy of entanglement]]) and form an [[orthonormal]] [[basis (linear algebra)]] of the Hilbert space of the two qubits. They play a fundamental role in [[Bell's theorem]].<br />
<br />
However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<br />
<br />
然而,关键的后续研究对这些结果的解释提出了质疑,并将报告的电子量子相干特征赋予了发色团中的核动力学。<br />
<br />
<br />
<br />
For M>2 qubits, the [[Greenberger–Horne–Zeilinger state|GHZ state]] is<br />
<br />
<br />
<br />
In 2020 researchers reported the quantum entanglement between the motion of a millimetre-sized mechanical oscillator and a disparate distant spin system of a cloud of atoms.<br />
<br />
2020年,研究人员报告了一个毫米大小的机械振荡器的运动和一个原子云的不同距离的自旋系统之间的量子纠缠。<br />
<br />
: <math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
<br />
<br />
<br />
which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to [[qudit]]s, i.e., systems of ''d'' rather than 2 dimensions.<br />
<br />
In October 2018, physicists reported producing quantum entanglement using living organisms, particularly between photosynthetic molecules within living bacteria and quantized light.<br />
<br />
2018年10月,物理学家报告说,他们利用活体生物制造量子纠缠,特别是利用活体细菌中的光合分子和量子化的光。<br />
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<br />
<br />
Also for M>2 qubits, there are [[Spin squeezing|spin squeezed states]].<ref>[http://qwiki.stanford.edu/index.php/Spin_Squeezed_State Database error – Qwiki] {{webarchive|url=https://web.archive.org/web/20120821011018/http://qwiki.stanford.edu/index.php/Spin_Squeezed_State |date=21 August 2012 }}</ref> Spin squeezed states are a class of [[squeezed coherent states]] satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled.<ref>{{cite journal | last1 = Kitagawa | first1 = Masahiro | last2 = Ueda | first2 = Masahito | year = 1993 | title = Squeezed Spin States | journal = Phys. Rev. A | volume = 47 | issue = 6| pages = 5138–5143 | doi=10.1103/physreva.47.5138| pmid = 9909547 |bibcode = 1993PhRvA..47.5138K }}</ref> Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<ref>{{cite journal | last1 = Wineland | first1 = D. J. | last2 = Bollinger | first2 = J. J. | last3 = Itano | first3 = W. M. | last4 = Moore | first4 = F. L. | last5 = Heinzen | first5 = D. J. | year = 1992| title = Spin squeezing and reduced quantum noise in spectroscopy | url = | journal = Phys. Rev. A | volume = 46| issue = 11| pages = R6797–R6800| doi = 10.1103/PhysRevA.46.R6797 | pmid = 9908086 |bibcode = 1992PhRvA..46.6797W }}</ref><br />
<br />
Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<br />
<br />
生物体(绿色硫细菌)已被研究作为介质,在非相互作用的光模式之间创造量子纠缠,表明光和细菌模式之间的高度纠缠,甚至在某种程度上纠缠在细菌内部。<br />
<br />
<br />
<br />
For two [[boson]]ic modes, a [[NOON state]] is<br />
<br />
<br />
<br />
: <math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
<br />
<br />
<br />
This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the ''N'' photons are in one mode" and "the ''N'' photons are in the other mode".<br />
<br />
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Finally, there also exist [[twin Fock states]] for bosonic modes, which can be created by feeding a [[Fock state]] into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.71.1355|pmid = 10055519|title = Interferometric detection of optical phase shifts at the Heisenberg limit|journal = Physical Review Letters|volume = 71|issue = 9|pages = 1355–1358|year = 1993|last1 = Holland|first1 = M. J|last2 = Burnett|first2 = K|bibcode = 1993PhRvL..71.1355H}}</ref><br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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=== Methods of creating entanglement ===<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is [[spontaneous parametric down-conversion]] to generate a pair of photons entangled in polarisation.<ref name="horodecki2007">{{cite journal |author=Horodecki R, Horodecki P, Horodecki M, Horodecki K |title=Quantum entanglement |journal=Rev. Mod. Phys. |arxiv=quant-ph/0702225 |doi =10.1103/RevModPhys.81.865 |year=2009|pages=865–942 |bibcode=2009RvMP...81..865H |volume=81 |issue=2|last2=Horodecki |last3=Horodecki |last4=Horodecki |s2cid=59577352 }}</ref> Other methods include the use of a [[fiber coupler]] to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a [[quantum dot]],<ref>{{Cite journal|last=Akopian|first=N.|date=2006|title=Entangled Photon Pairs from Semiconductor Quantum Dots|journal=Phys. Rev. Lett.|volume=96|issue=2|pages=130501|arxiv=quant-ph/0509060|bibcode=2006PhRvL..96b0501D|doi=10.1103/PhysRevLett.96.020501|pmid=16486553|s2cid=22040546}}</ref> the use of the [[Hong–Ou–Mandel effect]], etc., In the earliest tests of Bell's theorem, the entangled particles were generated using [[atomic cascade]]s.<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of [[Quantum teleportation#Entanglement swapping|entanglement swapping]]. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<ref>Rosario Lo Franco and Giuseppe Compagno, "Indistinguishability of Elementary Systems as a Resource for Quantum Information Processing", Phys. Rev. Lett. 120, 240403, 14 June 2018.</ref><br />
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=== Testing a system for entanglement ===<br />
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A density matrix ρ is called [[Separable state|separable]] if it can be written as a convex sum of product states, namely<br />
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<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple [[Peres–Horodecki criterion]] provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes [[NP-hard]] when generalized.<ref name="NP-hard1">Gurvits, L., Classical deterministic complexity of Edmonds' problem and quantum entanglement, in Proceedings of the 35th ACM Symposium on Theory of Computing, ACM Press, New York, 2003.</ref><ref name="NP-hard2">Sevag Gharibian, Strong NP-Hardness of the [[Quantum Separability Problem]], [[Quantum Information]] and what's known as [[Quantum Computing]], Vol. 10, No. 3&4, pp. 343–360, 2010. {{arXiv|0810.4507}}.</ref> Other separability criteria include (but not limited to) the [[range criterion]], [[reduction criterion]], and those based on uncertainty relations.<ref>{{cite journal |last1=Hofmann |first1=Holger F. |last2=Takeuchi |first2=Shigeki |title=Violation of local uncertainty relations as a signature of entanglement |journal=Physical Review A |date=22 September 2003 |volume=68 |issue=3 |page=032103 |doi=10.1103/PhysRevA.68.032103|arxiv=quant-ph/0212090 |bibcode=2003PhRvA..68c2103H |s2cid=54893300 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |title=Characterizing Entanglement via Uncertainty Relations |journal=Physical Review Letters |date=18 March 2004 |volume=92 |issue=11 |page=117903 |doi=10.1103/PhysRevLett.92.117903|pmid=15089173 |arxiv=quant-ph/0306194 |bibcode=2004PhRvL..92k7903G |s2cid=5696147 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |last2=Lewenstein |first2=Maciej |title=Entropic uncertainty relations and entanglement |journal=Physical Review A |date=24 August 2004 |volume=70 |issue=2 |page=022316 |doi=10.1103/PhysRevA.70.022316|bibcode=2004PhRvA..70b2316G |arxiv=quant-ph/0403219 |s2cid=118952931 }}</ref><ref>{{cite journal |last1=Huang |first1=Yichen |title=Entanglement criteria via concave-function uncertainty relations |journal=Physical Review A |date=29 July 2010 |volume=82 |issue=1 |page=012335 |doi=10.1103/PhysRevA.82.012335|bibcode=2010PhRvA..82a2335H }}</ref> See Ref.<ref>{{cite journal|last1=Gühne|first1=Otfried|last2=Tóth|first2=Géza|title=Entanglement detection|journal=Physics Reports|volume=474|issue=1–6|pages=1–75|doi=10.1016/j.physrep.2009.02.004|arxiv = 0811.2803 |bibcode = 2009PhR...474....1G |year=2009|s2cid=119288569}}</ref> for a review of separability criteria in discrete variable systems.<br />
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A numerical approach to the problem is suggested by [[Jon Magne Leinaas]], [[Jan Myrheim]] and [[Eirik Ovrum]] in their paper "Geometrical aspects of entanglement".<ref name="geom approach">{{cite journal | last1 = Leinaas| first1 = Jon Magne| last2 = Myrheim| first2 = Jan| last3 = Ovrum| first3 = Eirik| year = 2006 | title = Geometrical aspects of entanglement | url = | journal = Physical Review A | volume = 74 | issue = | page = 012313 | doi = 10.1103/PhysRevA.74.012313| arxiv = quant-ph/0605079| s2cid = 119443360}}</ref> Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in [[Peres-Horodecki criterion]] testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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In continuous variable systems, the [[Peres-Horodecki criterion]] also applies. Specifically, Simon <ref>{{cite journal|last1=Simon|first1=R.|title=Peres-Horodecki Separability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2726–2729|doi=10.1103/PhysRevLett.84.2726|arxiv = quant-ph/9909044 |bibcode = 2000PhRvL..84.2726S|pmid=11017310|year=2000|s2cid=11664720}}</ref> formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref.<ref>{{cite journal|last1=Duan|first1=Lu-Ming|last2=Giedke|first2=G.|last3=Cirac|first3=J. I.|last4=Zoller|first4=P.|title=Inseparability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2722–2725|doi=10.1103/PhysRevLett.84.2722|pmid=11017309|arxiv = quant-ph/9908056 |bibcode = 2000PhRvL..84.2722D |year=2000|s2cid=9948874}}</ref> for a seemingly different but essentially equivalent approach). It was later found <ref>{{cite journal|last1=Werner|first1=R. F.|last2=Wolf|first2=M. M.|title=Bound Entangled Gaussian States|journal=Physical Review Letters|volume=86|issue=16|pages=3658–3661|doi=10.1103/PhysRevLett.86.3658|pmid=11328047|arxiv = quant-ph/0009118 |bibcode = 2001PhRvL..86.3658W |year=2001|s2cid=20897950}}</ref> that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators <ref>{{cite journal|last1=Shchukin|first1=E.|last2=Vogel|first2=W.|title=Inseparability Criteria for Continuous Bipartite Quantum States|journal=Physical Review Letters|volume=95|issue=23|pages=230502|doi=10.1103/PhysRevLett.95.230502|pmid=16384285|arxiv = quant-ph/0508132 |bibcode = 2005PhRvL..95w0502S |year=2005|s2cid=28595936}}</ref><ref>{{cite journal|last1=Hillery|first1=Mark|last2=Zubairy|first2=M.Suhail|title=Entanglement Conditions for Two-Mode States|journal=Physical Review Letters|volume=96|issue=5|doi=10.1103/PhysRevLett.96.050503|arxiv = quant-ph/0507168 |bibcode = 2006PhRvL..96e0503H|pmid=16486912|page=050503|year=2006|s2cid=43756465}}</ref> or by using entropic measures.<ref>{{cite journal|last1=Walborn|first1=S.|last2=Taketani|first2=B.|last3=Salles|first3=A.|last4=Toscano|first4=F.|last5=de Matos Filho|first5=R.|title=Entropic Entanglement Criteria for Continuous Variables|journal=Physical Review Letters|volume=103|issue=16|doi=10.1103/PhysRevLett.103.160505|arxiv = 0909.0147 |bibcode = 2009PhRvL.103p0505W|pmid=19905682|page=160505|year=2009|s2cid=10523704}}</ref><ref>{{cite journal |last1=Yichen Huang |title=Entanglement Detection: Complexity and Shannon Entropic Criteria |journal=IEEE Transactions on Information Theory |date=October 2013 |volume=59 |issue=10 |pages=6774–6778 |doi=10.1109/TIT.2013.2257936|s2cid=7149863 }}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite.<ref>http://physicsworld.com/cws/article/news/2016/aug/16/china-launches-world-s-first-quantum-science-satellite</ref> The $100m [[Quantum Experiments at Space Scale]] (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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In the June 16, 2017, issue of ''Science'', Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<ref>{{cite journal | doi = 10.1126/science.aan3211 | volume=356 | title=Satellite-based entanglement distribution over 1200 kilometers | year=2017 | journal=Science | pages=1140–1144 | last1 = Yin | first1 = Juan | last2 = Cao | first2 = Yuan | last3 = Li | first3 = Yu-Huai | last4 = Liao | first4 = Sheng-Kai | last5 = Zhang | first5 = Liang | last6 = Ren | first6 = Ji-Gang | last7 = Cai | first7 = Wen-Qi | last8 = Liu | first8 = Wei-Yue | last9 = Li | first9 = Bo | last10 = Dai | first10 = Hui | last11 = Li | first11 = Guang-Bing | last12 = Lu | first12 = Qi-Ming | last13 = Gong | first13 = Yun-Hong | last14 = Xu | first14 = Yu | last15 = Li | first15 = Shuang-Lin | last16 = Li | first16 = Feng-Zhi | last17 = Yin | first17 = Ya-Yun | last18 = Jiang | first18 = Zi-Qing | last19 = Li | first19 = Ming | last20 = Jia | first20 = Jian-Jun | last21 = Ren | first21 = Ge | last22 = He | first22 = Dong | last23 = Zhou | first23 = Yi-Lin | last24 = Zhang | first24 = Xiao-Xiang | last25 = Wang | first25 = Na | last26 = Chang | first26 = Xiang | last27 = Zhu | first27 = Zhen-Cai | last28 = Liu | first28 = Nai-Le | last29 = Chen | first29 = Yu-Ao | last30 = Lu | first30 = Chao-Yang | last31 = Shu | first31 = Rong | last32 = Peng | first32 = Cheng-Zhi | last33 = Wang | first33 = Jian-Yu | last34 = Pan | first34 = Jian-Wei | issue=6343 | pmid = 28619937| doi-access = free }}</ref><ref>{{cite web | url=http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance | title=China's quantum satellite achieves 'spooky action' at record distance| date=2017-06-14}}</ref><br />
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== Naturally entangled systems ==<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be [[Configuration interaction|calculated]] only by consideration of electron entanglement.<ref>Frank Jensen: ''Introduction to Computational Chemistry.'' Wiley, 2007, {{ISBN|978-0-470-01187-4}}.</ref><br />
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== Photosynthesis ==<br />
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It has been suggested that in the process of [[photosynthesis]], entanglement is involved in the transfer of energy between [[light-harvesting complex]]es and [[photosynthetic reaction center]]s where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using [[femtosecond spectroscopy]], the coherence of entanglement in the [[Fenna-Matthews-Olson complex]] was measured over hundreds of [[femtosecond]]s (a relatively long time in this regard) providing support to this theory.<ref>Berkeley Lab Press Release: ''[http://newscenter.lbl.gov/feature-stories/2010/05/10/untangling-quantum-entanglement/ Untangling the Quantum Entanglement Behind Photosynthesis: Berkeley scientists shine new light on green plant secrets.]''</ref><ref>Mohan Sarovar, Akihito Ishizaki, Graham R. Fleming, K. Birgitta Whaley: ''Quantum entanglement in photosynthetic light harvesting complexes.'' {{arxiv|0905.3787}}</ref><br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<ref>{{cite journal | author = R. Tempelaar | author2 = T. L. C. Jansen | author3 = J. Knoester | title = Vibrational Beatings Conceal Evidence of Electronic Coherence in the FMO Light-Harvesting Complex | journal = J. Phys. Chem. B | volume = 118 | issue = 45 | pages = 12865–12872 | date = 2014 | doi=10.1021/jp510074q| pmid = 25321492 }}</ref><ref>{{cite journal | author = N. Christenson | author2 = H. F. Kauffmann | author3 = T. Pullerits | author4 = T. Mancal | title = Origin of Long-Lived Coherences in Light-Harvesting Complexes| journal = J. Phys. Chem. B | volume = 116 | issue = 25 | pages = 7449–7454 | date = 2012 | doi = 10.1021/jp304649c | pmid = 22642682 | pmc = 3789255 | bibcode = 2012arXiv1201.6325C | arxiv = 1201.6325 }}</ref><ref>{{cite journal | author = A. Kolli | author2 = E. J. O’Reilly | author3= G. D. Scholes | author4= A. Olaya-Castro | title = The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae| journal = J. Chem. Phys. | volume = 137 | issue = 17 | pages = 174109 | date = 2012 | doi=10.1063/1.4764100| pmid = 23145719 | bibcode = 2012JChPh.137q4109K | arxiv = 1203.5056 | s2cid = 20156821 }}</ref><ref>{{cite journal | author = V. Butkus | author2 = D. Zigmantas | author3= L. Valkunas | author4= D. Abramavicius | title = Vibrational vs. electronic coherences in 2D spectrum of molecular systems| journal = Chem. Phys. Lett. | volume = 545 | issue = 30 | pages = 40–43 | date = 2012 | doi=10.1016/j.cplett.2012.07.014| arxiv = 1201.2753 | bibcode = 2012CPL...545...40B | s2cid = 96663719 }}</ref><ref>{{cite journal | author = V. Tiwari | author2 = W. K. Peters | author3= D. M. Jonas | title = Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework | journal = Proc. Natl. Acad. Sci. USA | volume = 110 | issue = 4 | pages = 1203–1208 | date = 2013 | doi=10.1073/pnas.1211157110| pmid = 23267114 | pmc = 3557059 }}</ref><ref>{{cite journal | author = E. Thyrhaug | author2 = K. Zidek | author3 = J. Dostal | author4 = D. Bina | author5 = D. Zigmantas | title = Exciton Structure and Energy Transfer in the Fenna−Matthews− Olson Complex| journal = J. Phys. Chem. Lett. | volume = 7 | issue = 9 | pages = 1653–1660 | date = 2016 | doi=10.1021/acs.jpclett.6b00534| pmid = 27082631 }}</ref><ref>{{cite journal | author = Y. Fujihashi | author2 = G. R. Fleming | author3= A. Ishizaki | title = Impact of environmentally induced fluctuations on quantum mechanically mixed electronic and vibrational pigment states in photosynthetic energy transfer and 2D electronic spectra| journal = J. Chem. Phys. | volume = 142 | issue = 21 | pages = 212403 | date = 2015 | doi=10.1063/1.4914302| pmid = 26049423 | arxiv = 1505.05281 | bibcode = 2015JChPh.142u2403F | s2cid = 1082742 }}</ref><br />
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== Entanglement of macroscopic objects ==<br />
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In 2020 researchers reported the quantum entanglement between the [[Vibrations of a circular membrane|motion of a millimetre-sized mechanical oscillator]] and a disparate distant [[Spin (physics)|spin]] system of a cloud of atoms.<ref>{{cite news |title=Quantum entanglement realized between distant large objects |url=https://phys.org/news/2020-09-quantum-entanglement-distant-large.html |accessdate=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Thomas |first1=Rodrigo A. |last2=Parniak |first2=Michał |last3=Østfeldt |first3=Christoffer |last4=Møller |first4=Christoffer B. |last5=Bærentsen |first5=Christian |last6=Tsaturyan |first6=Yeghishe |last7=Schliesser |first7=Albert |last8=Appel |first8=Jürgen |last9=Zeuthen |first9=Emil |last10=Polzik |first10=Eugene S. |title=Entanglement between distant macroscopic mechanical and spin systems |journal=Nature Physics |date=21 September 2020 |pages=1–6 |doi=10.1038/s41567-020-1031-5 |url=https://www.nature.com/articles/s41567-020-1031-5 |accessdate=9 October 2020 |language=en |issn=1745-2481}}</ref><br />
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=== Entanglement of elements of living systems ===<br />
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In October 2018, physicists reported producing quantum entanglement using [[living organism]]s, particularly between photosynthetic molecules within living [[bacteria]] and [[Photon|quantized light]].<ref name="JPC-20181010">{{cite journal |last1=Marletto |first1=C. |last2=Coles |first2=D.M. |last3=Farrow |first3=T. |last4=Vedral |first4=V. |title=Entanglement between living bacteria and quantized light witnessed by Rabi splitting |date=10 October 2018 |journal=Journal of Physics: Communications |volume=2 |pages=101001 |number=10 |doi=10.1088/2399-6528/aae224 |bibcode=2018JPhCo...2j1001M |arxiv=1702.08075 |s2cid=119236759 }} [[File:CC-BY icon.svg|50px]] Text and images are available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref><ref name="SA-20181029">{{cite web |last=O'Callaghan |first=Jonathan |title="Schrödinger's Bacterium" Could Be a Quantum Biology Milestone – A recent experiment may have placed living organisms in a state of quantum entanglement |url=https://www.scientificamerican.com/article/schroedingers-bacterium-could-be-a-quantum-biology-milestone/ |date=29 October 2018 |work=[[Scientific American]] |accessdate=29 October 2018 }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<ref>{{cite journal | last1 = Krisnanda | first1 = T. | last2 = Marletto | first2 = C. | last3 = Vedral | first3 = V. | last4 = Paternostro | first4 = M. | last5 = Paterek | first5 = T. | year = 2018 | title = Probing quantum features of photosynthetic organisms | url = https://www.nature.com/articles/s41534-018-0110-2 | journal = NPJ Quantum Information | volume = 4 | issue = | page = 60 | doi = 10.1038/s41534-018-0110-2 | doi-access = free }}</ref><br />
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== See also ==<br />
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{{Portal|Physics}}<br />
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{{cols|colwidth=21em}}<br />
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* [[Quantum gate#Controlled gates|CNOT gate]]<br />
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* [[Bound entanglement]]<br />
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* [[Concurrence (quantum computing)]]<br />
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* [[Einstein's thought experiments]]<br />
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* [[Entanglement distillation]]<br />
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* [[Entanglement witness]]<br />
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* [[Faster-than-light communication]]<br />
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* [[Ghirardi–Rimini–Weber theory]]<br />
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* [[Multipartite entanglement]]<br />
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* [[Normally distributed and uncorrelated does not imply independent]]<br />
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* [[Observer effect (physics)]]<br />
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* [[Quantum coherence]]<br />
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* [[Quantum discord]]<br />
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* [[Quantum phase transition]]<br />
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* [[Quantum computing]]<br />
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* [[Quantum network]]<br />
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Category:Quantum information science<br />
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类别: 量子信息科学<br />
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* [[Quantum pseudo-telepathy]]<br />
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Category:Quantum mechanics<br />
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类别: 量子力学<br />
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* [[Quantum teleportation]]<br />
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Category:Unsolved problems in physics<br />
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类别: 物理学中未解决的问题<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Quantum entanglement]]. Its edit history can be viewed at [[量子纠缠/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%87%8F%E5%AD%90%E7%BA%A0%E7%BC%A0&diff=21229量子纠缠2021-01-23T11:46:17Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Correlation between measurements of quantum subsystems, even when spatially separated}}<br />
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[[File:SPDC figure.png|right|thumb|275px|[[Spontaneous parametric down-conversion]] process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[[Spontaneous parametric down-conversion process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[自发参量下转换过程可以将光子分裂成具有相互垂直极化的 II 型光子对。]<br />
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{{Quantum mechanics|fundamentals}}<br />
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'''Quantum entanglement''' is a physical phenomenon that occurs when a pair or group of [[particle]]s are generated, interact, or share spatial proximity in a way such that the [[quantum state]] of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the [[principle of locality|disparity between classical and quantum physics]]: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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量子纠缠是一种物理现象,描述的是当一对或一组粒子被产生、相互作用或共享空间邻近性时(包括当粒子被大距离分离时),该对或该组粒子中的每个粒子的量子态都无法独立于其他粒子的态。量子纠缠是经典物理学和量子物理学之间差别悬殊的核心问题:纠缠是量子力学的一个主要特征,而经典力学却没有这种特征。<br />
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[[Measurement#Quantum mechanics|Measurements]] of [[physical properties]] such as [[position (vector)|position]], [[momentum]], [[spin (physics)|spin]], and [[polarization (waves)|polarization]] performed on entangled particles can, in some cases, be found to be perfectly [[correlated]]. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly [[paradox]]ical effects: any measurement of a property of a particle results in an irreversible [[wave function collapse]] of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a property of a particle results in an irreversible wave function collapse of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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在某些情况下,对纠缠粒子的位置、动量、自旋和偏振等物理性质的测量的结果可以是完全相关的。例如,如果一对纠缠粒子的产生使得它们的总自旋已知为零,并且我们发现一个粒子在第一个轴上具有顺时针自旋,那么在同一个轴上测量的另一个粒子的自旋将会是逆时针的。然而,这种行为产生了看似矛盾的效应:对粒子性质的任何测量都会导致该粒子的不可逆波函数崩溃,并将改变原来的量子态。在粒子纠缠的情况下,这样的测量将影响整个纠缠系统。<br />
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Such phenomena were the subject of a 1935 paper by [[Albert Einstein]], [[Boris Podolsky]], and [[Nathan Rosen]],<ref name="Einstein1935"><br />
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Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen, and several papers by Erwin Schrödinger shortly thereafter, describing what came to be known as the EPR paradox. Einstein and others considered such behavior to be impossible, as it violated the local realism view of causality (Einstein referring to it as "spooky action at a distance") and argued that the accepted formulation of quantum mechanics must therefore be incomplete.<br />
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这些现象是阿尔伯特·爱因斯坦、鲍里斯·波多尔斯基和纳森·罗森在1935年发表的一篇论文和埃尔文·薛定谔随后不久发表的几篇论文的主题,这些论文描述了后来的EPR悖论。爱因斯坦和其他人认为这样的行为是不可能的,因为它违反了因果关系的局部实在论观点(爱因斯坦称之为“远处的幽灵行为”),并认为量子力学的公认公式因此一定是不完整的。<br />
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{{cite journal|author=Einstein A, Podolsky B, Rosen N|last2=Podolsky|last3=Rosen|year=1935|title=Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?|journal=Phys. Rev.|volume=47|issue=10|pages=777–780|bibcode=1935PhRv...47..777E|doi=10.1103/PhysRev.47.777|doi-access=free}}<br />
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</ref> and several papers by [[Erwin Schrödinger]] shortly thereafter,<ref name="Schrödinger1935"><br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<br />
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然而,后来,量子力学的反直觉预测在实验上得到了验证。所谓的“无漏洞”钟试验已经进行,在这种试验中,粒子位置被分开,以光速进行的通信将花费更长的时间——在一次实验中比测量间隔长10000倍<br />
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|author=Schrödinger E<br />
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According to some interpretations of quantum mechanics, the effect of one measurement occurs instantly. Other interpretations which don't recognize wavefunction collapse dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces correlation between the measurements and that the mutual information between the entangled particles can be exploited, but that any transmission of information at faster-than-light speeds is impossible.<br />
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根据量子力学的一些解释,一次测量的效果是瞬间发生的。其他不承认波函数崩塌的解释则认为不存在任何“效应”。然而,所有的解释都同意,纠缠产生了测量之间的相关性,纠缠粒子之间的互信息可以被利用,但任何信息的传输速度都不可能超过光速。<br />
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|title=Discussion of probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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Quantum entanglement has been demonstrated experimentally with photons, neutrinos, electrons, molecules as large as buckyballs, and even small diamonds. The utilization of entanglement in communication, computation and quantum radar is a very active area of research and development.<br />
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量子纠缠已经在光子、中微子、电子、巴基球大小的分子,甚至小钻石的实验中得到证实。纠缠在通信、计算和量子雷达中的应用是一个非常活跃的研究和发展领域。<br />
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|volume=31<br />
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|issue=4<br />
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|pages=555–563<br />
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Article headline regarding the [[Einstein–Podolsky–Rosen paradox (EPR paradox) paper, in the May 4, 1935 issue of The New York Times.]]<br />
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文章标题关于[爱因斯坦-波多尔斯基-罗森悖论(EPR paradox)论文,发表于1935年5月4日的《纽约时报》]<br />
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|year=1935<br />
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|doi=10.1017/S0305004100013554<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.<br />
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1935年,阿尔伯特·爱因斯坦与鲍里斯·波多尔斯基和纳森·罗森在一篇联合论文中首次讨论了量子力学关于强关联系统的反直觉预测。 <br />
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|bibcode = 1935PCPS...31..555S }}</ref><ref name="Schrödinger1936"><br />
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{{cite journal |author=Schrödinger E<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated: Einstein later famously derided entanglement as "spukhafte Fernwirkung" or "spooky action at a distance."<br />
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此后不久,薛定谔发表了一篇影响深远的论文,定义并讨论了“纠缠”的概念在论文中,他承认了这个概念的重要性,并指出了爱因斯坦后来众所周知的对纠缠的嘲弄“幽灵般的超距作用”<br />
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|title=Probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously Bohm's interpretation of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when John Stewart Bell proved that one of their key assumptions, the principle of locality, as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是Bohm对量子力学的解释),但发表的其他工作相对较少。尽管如此,直到1964年,约翰·斯图尔特·贝尔(John Stewart Bell)证明了他们的一个关键假设,即应用于EPR所希望的隐变量解释的局部性原理,在数学上与量子理论的预测不一致,EPR的论点中的弱点至此才被发现。<br />
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|volume=32<br />
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|issue=3<br />
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Specifically, Bell demonstrated an upper limit, seen in Bell's inequality, regarding the strength of correlations that can be produced in any theory obeying local realism, and showed that quantum theory predicts violations of this limit for certain entangled systems. His inequality is experimentally testable, and there have been numerous relevant experiments, starting with the pioneering work of Stuart Freedman and John Clauser in 1972 and Alain Aspect's experiments in 1982. An early experimental breakthrough was due to Carl Kocher, Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles. Alain Aspect notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / superdeterminism loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<br />
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具体来说,贝尔证明了一个上限,可以在贝尔不等式中看到,关于遵循局部实在论的任何理论中可以产生的关联强度,并表明量子理论预测某些纠缠系统会违反这个极限。从1972年斯图亚特·弗里德曼和约翰·克劳瑟的开创性工作和1982年阿兰·阿斯佩的实验开始,他的不等式在实验上是可以检验的,并且存在许多相关的实验。早期的实验突破归功于卡尔·科彻,科彻的仪器配备了更好的偏振器,弗里德曼和克劳瑟使用了这种仪器,他们可以证实余弦平方依赖性,并用它来证明对一组固定角度的贝尔不等式的违反。阿兰·阿斯佩指出的则是“设置独立漏洞”——他称之为“牵强的”,然而,“不可忽视”的“剩余漏洞”——还没有被关闭,并且自由意志/超决定论的漏洞是无法弥补的;他说“没有任何实验,尽可能的理想情况,可以说是完全没有漏洞的。” <br />
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|pages=446–452<br />
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|year=1936<br />
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A minority opinion holds that although quantum mechanics is correct, there is no superluminal instantaneous action-at-a-distance between entangled particles once the particles are separated.<br />
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少数人认为,尽管量子力学是正确的,但是一旦粒子分离,纠缠的粒子之间并不存在超光速瞬时作用。<br />
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|doi=10.1017/S0305004100019137<br />
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|bibcode = 1936PCPS...32..446S }}<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of quantum key distribution protocols, most famously BB84 by Charles H. Bennett and Gilles Brassard and E91 by Artur Ekert. Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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贝尔的工作提出了利用这些超强相关性作为交流资源的可能性。它导致了1984年量子密钥分配协议的发现,其中最著名的是查尔斯·H·班纳特和吉尔斯 布拉萨德的BB84和艾特 艾克特的E91。虽然BB84不使用纠缠,但是艾克特的协议使用了对Bell不等式的违反作为安全性的证明。 <br />
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</ref> describing what came to be known as the [[EPR paradox]]. Einstein and others considered such behavior to be impossible, as it violated the [[local realism]] view of causality (Einstein referring to it as "spooky [[action at a distance]]")<ref>Physicist John Bell depicts the Einstein camp in this debate in his article entitled "Bertlmann's socks and the nature of reality", p. 143 of ''Speakable and unspeakable in quantum mechanics'': "For EPR that would be an unthinkable 'spooky action at a distance'. To avoid such action at a distance they have to attribute, to the space-time regions in question, real properties in advance of observation, correlated properties, which predetermine the outcomes of these particular observations. Since these real properties, fixed in advance of observation, are not contained in quantum formalism, that formalism for EPR is incomplete. It may be correct, as far as it goes, but the usual quantum formalism cannot be the whole story." And again on p. 144 Bell says: "Einstein had no difficulty accepting that affairs in different places could be correlated. What he could not accept was that an intervention at one place could influence, immediately, affairs at the other." Downloaded 5 July 2011 from {{cite book |year=1987 |accessdate=2014-06-14 |title=Speakable and Unspeakable in Quantum Mechanics |first=J. S. |last=Bell |publisher=[[CERN]] |isbn=0521334950 |url=http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20150412044550/http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |archivedate=12 April 2015 |df=dmy-all }}</ref> and argued that the accepted formulation of [[quantum mechanics]] must therefore be incomplete.<br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally<ref name=":0" /><ref name=":1" /><ref name=":2" /> in tests in which polarization or spin of entangled particles were measured at separate locations, statistically violating [[Bell's inequality]]. In earlier tests, it couldn't be absolutely ruled out that the test result at one point could have been [[Loopholes in Bell test experiments|subtly transmitted]] to the remote point, affecting the outcome at the second location.<ref name=":2">Francis, Matthew.<br />
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[https://arstechnica.com/science/2012/10/quantum-entanglement-shows-that-reality-cant-be-local/ Quantum entanglement shows that reality can't be local], ''Ars Technica'', 30 October 2012</ref> However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<ref name=":1">{{cite journal|last1=Matson|first1=John|title=Quantum teleportation achieved over record distances|journal=Nature News|date=13 August 2012|doi=10.1038/nature.2012.11163|s2cid=124852641}}</ref><ref name=":0">{{cite journal<br />
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| title =Bounding the speed of 'spooky action at a distance<br />
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An entangled system is defined to be one whose quantum state cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or superposition, of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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一个纠缠系统被定义为一个量子态不能被分解为其局部成分的态的乘积的系统,也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部组分状态积的和或叠加;如果这个和必然有多个项,它就被纠缠。<br />
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| journal =Physical Review Letters |volume=110 | issue =26 |page=260407<br />
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| year =2013<br />
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Quantum systems can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on methods. Entanglement is broken when the entangled particles decohere through interaction with the environment; for example, when a measurement is made.<br />
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量子系统可以通过各种类型的相互作用而纠缠在一起。为了实验的目的,纠缠可以通过一些方法实现,请参见下面的方法部分。当纠缠的粒子通过与环境的相互作用而退离时,例如在进行测量时,纠缠就被打破了。 <br />
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| arxiv =1303.0614<br />
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As an example of entanglement: a subatomic particle decays into an entangled pair of other particles. The decay events obey the various conservation laws, and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a spin-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be spin up on some axis, the other, when measured on the same axis, is always found to be spin down. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the singlet state.)<br />
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作为纠缠的一个例子:一个亚原子粒子衰变为一对纠缠的其他粒子。衰变事件遵循各种守恒定律,因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(以便总动量、角动量、能量等在此过程前后保持大致相同)。例如,一个自旋为零的粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量到自旋向上时,另一个粒子在同一个轴上被测量时,总是被发现是自旋向下。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于单线态)。<br />
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| doi = 10.1103/PhysRevLett.110.260407<br />
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| pmid =23848853 | last1 =Yin | first1 =Juan | last2 =Cao | first2 =Yuan | last3 =Yong | first3 =Hai-Lin | last4 =Ren | first4 =Ji-Gang | last5 =Liang | first5 =Hao | last6 =Liao | first6 =Sheng-Kai | last7 =Zhou | first7 =Fei | last8 =Liu | first8 =Chang | last9 =Wu | first9 =Yu-Ping | last10 =Pan | first10 =Ge-Sheng | last11 =Li | first11 =Li | last12 =Liu | first12 =Nai-Le | last13 =Zhang | first13 =Qiang | last14 =Peng | first14 =Cheng-Zhi | last15 =Pan | first15 =Jian-Wei | s2cid =119293698 }}</ref><br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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如果将这两种粒子分开,可以更好地观察到纠缠的特性。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫。现在,如果我们测量其中一个粒子的特性(比如自旋) ,得到一个结果,然后用同样的标准(沿着同样的轴自旋)测量另一个粒子,我们发现第二个粒子的测量结果将匹配(在补充意义上)第一个粒子的测量结果,因为它们的值将相反。<br />
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According to ''some'' [[interpretations of quantum mechanics]], the effect of one measurement occurs instantly. Other interpretations which don't recognize [[wavefunction collapse]] dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces ''[[correlation]]'' between the measurements and that the [[mutual information]] between the entangled particles can be exploited, but that any ''transmission'' of information at faster-than-light speeds is impossible.<ref>[[Roger Penrose]], ''The Road to Reality: A Complete Guide to the Laws of the Universe'', London, 2004, p. 603.</ref><ref name="Griffiths2004">{{citation | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |isbn= 978-0-13-111892-8}}</ref><br />
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根据“一些”[[量子力学的解释]],一次测量的效果瞬间发生。其他不承认[[波函数崩溃]]的解释则认为存在任何“效应”。然而,所有的解释都同意,纠缠在测量值之间产生了“[[相关]]”,并且纠缠粒子之间的[[互信息]]可以被利用,但是任何以高于光速的信息“传输”都是不可能的。 <br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a hidden variable theory (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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上述结果可能会或不会被认为是令人惊讶的。一个经典系统也会表现出同样的性质,而一个隐藏变量理论(见下文)肯定会被要求这样做,它建立在经典力学和量子力学的角动量守恒的基础上。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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Quantum entanglement has been demonstrated experimentally with [[photon]]s,<ref name="Kocher1">{{cite journal | doi = 10.1103/PhysRevLett.18.575 | volume=18 | issue=15 | title=Polarization Correlation of Photons Emitted in an Atomic Cascade | journal=Physical Review Letters | pages=575–577 | last1 = Kocher | first1 = CA | last2 = Commins | first2 = ED | year=1967| url=http://www.escholarship.org/uc/item/1kb7660q | bibcode=1967PhRvL..18..575K }}</ref><ref name="Kocherphd">Carl A. Kocher, Ph.D. Thesis (University of California at Berkeley, 1967). ''[https://escholarship.org/uc/item/1kb7660q Polarization Correlation of Photons Emitted in an Atomic Cascade]''</ref> [[neutrino]]s,<ref>J. A. Formaggio, D. I. Kaiser, M. M. Murskyj, and T. E. Weiss (2016), "[https://journals.aps.org/prl/accepted/6f072Y00C3318d41f5739ec7f83a9acf1ad67b002 Violation of the Leggett-Garg inequality in neutrino oscillations]". ''Phys. Rev. Lett.'' Accepted 23 June 2016.</ref> [[electron]]s,<ref name="NTR-20151021">{{cite journal |author=Hensen, B. |title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres |date=21 October 2015 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature15759 |display-authors=etal |volume=526 |issue=7575 |pages=682–686|bibcode = 2015Natur.526..682H |pmid=26503041|arxiv=1508.05949 |hdl=2117/79298 |s2cid=205246446 }} See also [http://www.nature.com/articles/nature15759.epdf?referrer_access_token=1QB20mTNTZW60nEXil0D79RgN0jAjWel9jnR3ZoTv0Pfu6MWINxm4Io03p2jIRZ8qX_3I3N0Kr-AlItuikCZOJrG8QbdRRghlecFwmixlbQpWuw1dtaib4Le5DQOG3u_aXHU85x1JEhOcQTa1sHi0yvW23bblxmEQZAmHL4G0gIVusG_6JWorroY5BprgbTl4FiaE8WltEgMoUMZfZBkEfbMcFDp5iR112TFx_x3ZRj88Wa23E2moEvTfKjtlued0&tracking_referrer=www.nytimes.com free online access version].</ref><ref name="NYT-20151021">{{cite news |last=Markoff |first=Jack |title=Sorry, Einstein. Quantum Study Suggests 'Spooky Action' Is Real. |url=https://www.nytimes.com/2015/10/22/science/quantum-theory-experiment-said-to-prove-spooky-interactions.html |date=21 October 2015 |work=The New York Times |accessdate=21 October 2015 }}</ref> [[molecule]]s as large as [[buckyball]]s,<ref>{{cite journal | doi = 10.1038/44348 | title = Wave–particle duality of C<sub>60</sub> molecules | date= 14 October 1999 | volume=401 | issue = 6754 | journal=Nature | pages=680–682 | pmid=18494170|bibcode = 1999Natur.401..680A | last1 = Arndt | first1 = M | last2 = Nairz | first2 = O | last3 = Vos-Andreae | first3 = J | last4 = Keller | first4 = C | last5 = van der Zouw | first5 = G | last6 = Zeilinger | first6 = A| s2cid = 4424892 }} {{subscription}}</ref><ref>[[Olaf Nairz]], [[Markus Arndt]], and [[Anton Zeilinger]], "Quantum interference experiments with large molecules", American Journal of Physics, 71 (April 2003) 319–325.</ref> and even small diamonds.<ref>{{cite journal |journal=Science |date=2 December 2011 |volume=334 |issue=6060 |pages=1253–1256 |doi=10.1126/science.1211914 |pmid=22144620 |url=http://www.sciencemag.org/content/334/6060/1253.full |title=Entangling macroscopic diamonds at room temperature |lay-url=https://www.newscientist.com/article/dn21235-entangled-diamonds-blur-quantumclassical-divide.html|bibcode = 2011Sci...334.1253L |last1=Lee |first1=K. C. |last2=Sprague |first2=M. R. |last3=Sussman |first3=B. J. |last4=Nunn |first4=J. |last5=Langford |first5=N. K. |last6=Jin |first6=X.- M. |last7=Champion |first7=T. |last8=Michelberger |first8=P. |last9=Reim |first9=K. F. |last10=England |first10=D. |last11=Jaksch |first11=D. |last12=Walmsley |first12=I. A. |s2cid=206536690 }}</ref><ref>[http://www.sciencemag.org/content/334/6060/1253/suppl/DC1 sciencemag.org], supplementary materials</ref> The utilization of entanglement in [[quantum communication|communication]], [[quantum computing|computation]] and [[quantum radar]] is a very active area of research and development.<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<br />
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矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能比光传播得快),因此确保纠缠对的另一部分的测量结果是“正确的”。在哥本哈根解释中,对其中一个粒子的自旋测量的结果是坍缩成一种状态,其中每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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== History 历史==<br />
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[[File:NYT May 4, 1935.jpg|right|thumb| 250px|Article headline regarding the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox) paper, in the May 4, 1935 issue of ''[[The New York Times]]''.]]<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, hence, any causal effect connecting the events would have to travel faster than light. According to the principles of special relativity, it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events and there are inertial frames in which is first and others in which is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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我们可以选择测量的距离和时间,以便使两次测量之间的间隔像空间一样,因此,连接事件的任何因果效应都必须比光传播得更快。根据狭义相对论的原理,任何信息都不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量值是第一个。对于两个分离的类空事件,存在惯性系,有惯性系在其中是第一位的,也有其他惯性系在其中是第一位的。因此,这两种测量之间的相关性不能解释为一种测量决定另一种测量:不同的观察者会对因果关系的作用产生分歧。<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by [[Albert Einstein]] in 1935, in a joint paper with [[Boris Podolsky]] and [[Nathan Rosen]].<ref name="Einstein1935"/><br />
1935年阿尔伯特 爱因斯坦与鲍里斯 波多斯基和纳兰 罗森在一篇联合论文中首次讨论了关于强关联系统的量子力学的反直觉预测。 <br />
(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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(事实上,即使没有纠缠,也会出现类似的悖论:单个粒子的位置分布在空间上,两个试图在两个不同位置检测粒子的大范围分离的探测器必须立即获得适当的相关性,这样它们就不会同时检测到粒子。)<br />
In this study, the three formulated the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox), a [[thought experiment]] that attempted to show that [[quantum mechanics|quantum mechanical theory]] was [[Incompleteness of quantum physics|incomplete]]. They wrote: "We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete."<ref name="Einstein1935"/><br />
在这项研究中,三人提出了[[爱因斯坦-波多尔斯基-罗森悖论]](EPR悖论),一个[[思维实验]],试图证明[[量子力学|量子力学理论]]是[[量子物理的不完全性|不完全性]]。他们写道:“因此,我们被迫得出结论,波函数给出的物理实在的量子力学描述并不完整。” <br />
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However, the three scientists did not coin the word ''entanglement'', nor did they generalize the special properties of the state they considered. Following the EPR paper, [[Erwin Schrödinger]] wrote a letter to Einstein in [[German language|German]] in which he used the word ''Verschränkung'' (translated by himself as ''entanglement'') "to describe the correlations between two particles that interact and then separate, as in the EPR experiment."<ref name=MK>Kumar, M., ''Quantum'', Icon Books, 2009, p. 313.</ref><br />
然而,这三位科学家并没有创造“纠缠”这个词,也没有概括出他们所考虑的状态的特殊性质。在EPR论文发表之后,[[埃尔温·薛定谔]]用德语给爱因斯坦写了一封信,信中他用“Verschränkung”(他自己翻译为“纠缠”)一词来描述两个相互作用然后分离的粒子之间的关联,就像EPR实验中那样。” <br />
A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables". The state of the particles being measured contains some hidden variables, whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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解决这一悖论的一个可能办法是假设量子理论是不完整的,测量结果取决于预先确定的“隐藏变量”。被测粒子的状态包含一些隐藏的变量,这些变量的值从分离的那一刻起就有效地决定了自旋测量的结果。这就意味着每个粒子都携带着所需的全部信息,在测量时不需要从一个粒子传输到另一个粒子。爱因斯坦和其他人(见上一节)最初认为这是摆脱悖论的唯一途径,而公认的量子力学描述(带有随机测量结果)肯定是不完整的。<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated:<ref name="Schrödinger1935"/> "I would not call [entanglement] ''one'' but rather ''the'' characteristic trait of [[quantum mechanics]], the one that enforces its entire departure from [[Classical mechanics|classical]] lines of thought."<br />
此后不久,薛定谔发表了一篇开创性的论文,对“纠缠”的概念进行了定义和讨论。在论文中,他认识到了这个概念的重要性,并指出:“我不会将[纠缠]称为‘一’,而是称之为[量子力学]的‘特性’。”,它完全背离了[[经典力学|经典]]的思路。” <br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the local realist or hidden variables view were correct, the results would always satisfy Bell's inequality. A number of experiments have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists. When measurements of the entangled particles are made in moving relativistic reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<br />
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然而,当考虑沿不同轴的纠缠粒子自旋的测量时,局部隐变量理论是失败的。如果进行了大量成对的此类测量(在大量成对的纠缠粒子上),那么在统计上,如果局部现实主义或隐藏变量的观点是正确的,结果将始终满足贝尔不等式。大量的实验表明,贝尔不等式在实践中是不成立的。然而,在2015年之前,被物理学家群体认为是最关键的是所有这些实践都有漏洞问题,。当在运动的相对论参考系中对纠缠粒子进行测量时,每个测量(在它自己的相对论时间范围内)都发生在另一个之前,测量结果将保持相关。<br />
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Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the [[theory of relativity]].<ref>Alisa Bokulich, Gregg Jaeger, ''Philosophy of Quantum Information and Entanglement'', Cambridge University Press, 2010, xv.</ref> Einstein later famously derided entanglement as "''spukhafte Fernwirkung''"<ref name="spukhafte">Letter from Einstein to Max Born, 3 March 1947; ''The Born-Einstein Letters; Correspondence between Albert Einstein and Max and Hedwig Born from 1916 to 1955'', Walker, New York, 1971. (cited in {{citation | title = Quantum Entanglement and Communication Complexity (1998) | journal = SIAM J. Comput. | volume = 30 | issue = 6 | citeseerx = 10.1.1.20.8324 | author = M. P. Hobson |pages=1829–1841 | display-authors = etal | year = 1998 }})</ref> or "spooky [[Action at a distance (physics)|action at a distance]]."<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are incompatible in the sense that these measurements' maximum simultaneous precision is constrained by the uncertainty principle. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations, and thus entanglement is a fundamentally non-classical phenomenon.<br />
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沿不同轴线测量自旋的基本问题是,这些测量不可能同时具有确定的值——它们是不相容的,因为这些测量的最大同时精度受到不确定性原理的限制。这与经典物理学中的发现相反,在经典物理学中,任何数量的性质都可以以任意精度同时测量。从数学上证明了相容测量不能显示违反贝尔不等式的关联,因此纠缠是一个基本的非经典现象。<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously [[De Broglie–Bohm theory|Bohm's interpretation]] of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when [[John Stewart Bell]] proved that one of their key assumptions, the [[principle of locality]], as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是量子力学的[[De Broglie–Bohm 理论 | Bohm表达]]),但其他发表的著作相对较少。尽管有人对此感兴趣,但直到1964年,[[约翰·斯图尔特·贝尔]]证明了他们的一个关键假设,[[局域性原理]],即应用于EPR希望解释的隐藏变量,在数学上与量子理论的预测不一致时,EPR论点中的漏洞才被发现。<br />
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Entanglement is required to preserve the Uncertainty principle, as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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纠缠是保持不确定性原理所必需的,如 EPR 悖论所示。例如,假设一个高能光子衰变成一个电子/正电子对,然后测量电子的位置和正电子的动量。如果我们在物理描述中不允许纠缠,那么每个粒子的位置和动量就可以通过参考动量守恒来推导,这就违反了测不准原理。或者,如果我们要求不确定性原理保持真实,而仍然不允许在物理上描述对的纠缠,不确定性原理将会违反动量守恒定律,因为在位置和动量上强相关性是不可能的(也就是说,人们不能有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关)。--><br />
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Specifically, Bell demonstrated an upper limit, seen in [[Bell's inequality]], regarding the strength of correlations that can be produced in any theory obeying [[local realism]], and showed that quantum theory predicts violations of this limit for certain entangled systems.<ref>{{cite journal |author = J. S. Bell |title = On the Einstein-Poldolsky-Rosen paradox |journal = Physics Physique Физика |volume = 1 |issue = 3 |pages = 195–200 |year = 1964|doi = 10.1103/PhysicsPhysiqueFizika.1.195 |doi-access = free }}</ref> His inequality is experimentally testable, and there have been numerous [[Bell test experiments|relevant experiments]], starting with the pioneering work of [[Stuart Freedman]] and [[John Clauser]] in 1972<ref name="Clauser">{{cite journal|doi=10.1103/PhysRevLett.28.938|last1=Freedman|first1=Stuart J.|last2=Clauser|first2=John F.|title=Experimental Test of Local Hidden-Variable Theories|journal=Physical Review Letters |volume=28 |issue=14 |pages=938–941|year=1972 |bibcode=1972PhRvL..28..938F|url=https://escholarship.org/uc/item/2f18n5nk}}</ref> and [[Alain Aspect]]'s experiments in 1982.<ref>{{cite journal |author1=A. Aspect |author2=P. Grangier |author3=G. Roger |name-list-style=amp |title = Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell's Inequalities |journal = Physical Review Letters |volume = 49 |issue = 2 |pages = 91–94 |year = 1982 |doi = 10.1103/PhysRevLett.49.91 |bibcode=1982PhRvL..49...91A|doi-access = free }}</ref> An early experimental breakthrough was due to Carl Kocher,<ref name="Kocher1"/><ref name="Kocherphd"/> who already in 1967 presented an apparatus in which two photons successively emitted from a calcium atom were shown to be entangled – the first case of entangled visible light. The two photons passed diametrically positioned parallel polarizers with higher probability than classically predicted but with correlations in quantitative agreement with quantum mechanical calculations. He also showed that the correlation varied only upon (as cosine square of) the angle between the polarizer settings<ref name="Kocherphd"/> and decreased exponentially with time lag between emitted photons.<ref name="Kocher2">{{cite journal | doi = 10.1016/0003-4916(71)90159-X | volume=65 | issue=1 | title=Time correlations in the detection of successively emitted photons | journal=Annals of Physics | pages=1–18 | last1 = Kocher | first1 = CA | year=1971| bibcode=1971AnPhy..65....1K }}</ref> Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles.<ref name="Clauser"/> All these experiments have shown agreement with quantum mechanics rather than the principle of local realism.<br />
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For decades, each had left open at least one [[Loopholes in Bell test experiments|loophole]] by which it was possible to question the validity of the results. However, in 2015 an experiment was performed that simultaneously closed both the detection and locality loopholes, and was heralded as "loophole-free"; this experiment ruled out a large class of local realism theories with certainty.<ref name="hanson">{{cite journal|last1=Hanson|first1=Ronald|title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres|journal=Nature|volume=526|issue=7575|pages=682–686|doi=10.1038/nature15759|arxiv=1508.05949|bibcode = 2015Natur.526..682H|pmid=26503041|year=2015|s2cid=205246446}}</ref> [[Alain Aspect]] notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / ''[[superdeterminism]]'' loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<ref>{{Cite journal | title=Viewpoint: Closing the Door on Einstein and Bohr's Quantum Debate| journal=Physics| volume=8| date=2015-12-16| last1=Aspect| first1=Alain| page=123| doi=10.1103/physics.8.123| doi-access=free| bibcode=2015PhyOJ...8..123A}}</ref><br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time. The authors claimed that this result was achieved by entanglement swapping between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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在2012年和2013年的实验中,在时间上从未共存的光子之间产生了偏振关联。作者认为,这一结果是在测量了一对纠缠光子的偏振态后,通过两对纠缠光子之间的纠缠交换得到的,证明了量子非定域性不仅适用于空间,也适用于时间。 <br />
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A minority opinion holds that although quantum mechanics is correct, there is no [[faster-than-light|superluminal]] instantaneous action-at-a-distance between entangled particles once the particles are separated.<ref>{{Cite journal |doi = 10.1142/S0217979206034078|title = Correlations in Entangled States|journal = International Journal of Modern Physics B|volume = 20|issue = 11n13|pages = 1496–1503|year = 2006|last1 = Sanctuary|first1 = B. C|arxiv = quant-ph/0508238|bibcode = 2006IJMPB..20.1496S|s2cid = 119403050}}</ref><ref>{{Cite arxiv |eprint = quant-ph/0404011 |last1 = Yin |first1 = Juan |title = The Statistical Interpretation of Entangled States |last2 = Cao |first2 = Yuan |last3 = Yong |first3 = Hai-Lin |last4 = Ren |first4 = Ji-Gang |last5 = Liang |first5 = Hao |last6 = Liao |first6 = Sheng-Kai |last7 = Zhou |first7 = Fei |last8 = Liu |first8 = Chang |last9 = Wu |first9 = Yu-Ping |last10 = Pan |first10 = Ge-Sheng |last11 = Zhang |first11 = Qiang |last12 = Peng |first12 = Cheng-Zhi |last13 = Pan |first13 = Jian-Wei |year = 2004 }}</ref><ref>{{cite journal|doi=10.1002/prop.201600044 | volume=65 | issue=6–8 | title=After Bell | year=2016 | journal=Fortschritte der Physik | page=1600044 | last1 = Khrennikov | first1 = Andrei}}</ref><ref>{{Cite journal |arxiv = 1603.08674|last1 = Yin|first1 = Juan|title = After Bell|journal = Fortschritte der Physik (Progress in Physics)|date=2017|volume = 65|issue = 1600014|pages = 6–8|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|bibcode = 2016arXiv160308674K}}</ref><ref>{{Cite journal |arxiv = quant-ph/0703251|last1 = Yin|first1 = Juan|title = Classical statistical distributions can violate Bell-type inequalities|journal = Journal of Physics A: Mathematical and Theoretical|volume = 41|issue = 8|pages = 085303|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|year = 2007|doi = 10.1088/1751-8113/41/8/085303|s2cid = 46193162}}</ref><br />
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In three independent experiments in 2013 it was shown that classically communicated separable quantum states can be used to carry entangled states. The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<br />
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2013年的三个独立实验表明,经典通信的可分离量子态可以用来携带纠缠态。第一次无漏洞贝尔试验于2015年在图代尔夫特举行,证实了贝尔不等式的不成立。 <br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of [[quantum key distribution]] protocols, most famously [[BB84]] by [[Charles H. Bennett (computer scientist)|Charles H. Bennett]] and [[Gilles Brassard]]<ref>C. H. Bennett and G. Brassard. "Quantum cryptography: Public key distribution and coin tossing". In ''Proceedings of IEEE International Conference on Computers, Systems and Signal Processing'', volume 175, p. 8. New York, 1984. http://researcher.watson.ibm.com/researcher/files/us-bennetc/BB84highest.pdf</ref> and [[E91 protocol|E91]] by [[Artur Ekert]].<ref>{{cite journal|last=Ekert|first=A.K.|authorlink=Artur Ekert|title=Quantum cryptography based on Bell's theorem|journal=Phys. Rev. Lett.|volume=67|issue=6|year=1991|doi=10.1103/PhysRevLett.67.661|issn=0031-9007|bibcode = 1991PhRvL..67..661E|pmid=10044956|pages=661–663}}</ref> Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<br />
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2014年8月,巴西研究人员加布里埃拉·巴雷托·莱莫斯和他的团队能够使用光子“拍摄”物体,这些光子并没有与实验对象发生相互作用,而是与这些物体发生了纠缠。来自维也纳大学的勒莫斯相信,这种新的量子成像技术可以在微光成像势在必行的领域找到应用,比如生物或医学成像。<br />
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== Concept 概念==<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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2015年,哈佛大学的马克斯·格雷纳团队直接测量了超冷玻色子原子系统中的Renyi纠缠。<br />
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=== Meaning of entanglement纠缠的意义 ===<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<br />
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从2016年起,IBM、微软等多家公司成功创建了量子计算机,并允许开发人员和技术爱好者公开实验量子力学的概念,这其中就包括量子纠缠。 <br />
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An entangled system is defined to be one whose [[quantum state]] cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or [[quantum superposition|superposition]], of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
纠缠系统被定义为其[[量子态]]不能被分解为其局部成分的态的乘积;也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部成分的状态积的和,或[[量子叠加|叠加]],如果这个和一定有一个以上的项,那么它是纠缠的。<br />
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Quantum [[physical system|systems]] can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on [[#Methods of creating entanglement|methods]]. Entanglement is broken when the entangled particles [[quantum decoherence|decohere]] through interaction with the environment; for example, when a measurement is made.<ref name="Peres1993">Asher Peres, ''[[Quantum Theory: Concepts and Methods]]'', Kluwer, 1993; {{ISBN|0-7923-2549-4}} p. 115.</ref><br />
量子[[物理系统|系统]]可以通过各种类型的相互作用而纠缠在一起。为了实验目的而实现纠缠的一些方法,请参见下面关于[[#创建纠缠的方法|方法]]的部分。当纠缠粒子通过与环境的相互作用[[量子退相干|退相干]]时,例如在进行测量时,纠缠将被打破。<br />
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There have been suggestions to look at the concept of time as an emergent phenomenon that is a side effect of quantum entanglement.<br />
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有人建议把时间的概念看作是量子纠缠的副作用的一种自然现象。<br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by Don Page and William Wootters in 1983.<br />
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换句话说,时间是一种纠缠现象,它将所有相等的时钟读数(正确准备的时钟或任何可用作时钟的物体的读数)放入同一个历史中。1983年,唐·佩奇和威廉·伍特斯首次提出了这一理论<br />
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As an example of entanglement: a [[subatomic particle]] [[Particle decay|decays]] into an entangled pair of other particles. The decay events obey the various [[conservation laws]], and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a [[Spin (physics)|spin]]-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be [[Spin (physics)#Direction|spin up]] on some axis, the other, when measured on the same axis, is always found to be [[Spin (physics)#Direction|spin down]]. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the [[singlet state]].)<br />
作为纠缠的一个例子:一个[[亚原子粒子]][[粒子衰变|衰变]]变成一对纠缠的其他粒子。衰变事件遵循各种[[守恒定律]],因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(因此总动量、角动量、能量等在此过程前后保持大致相同)。例如,[[自旋(物理)|自旋]]-零粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量为[[自旋(物理)方向|自旋向上]],另一个粒子在同一个轴上被测量时,总是被发现为[[自旋(物理)#方向|自旋向下]]。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于[[单态]]。)<br />
The Wheeler–DeWitt equation that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<br />
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20世纪60年代,惠勒-德威特方程引入了广义相对论和量子力学的概念,并于1983年再次引入,当时佩奇和伍特基于量子纠缠方程提出了一个解决方案。佩奇和伍特斯认为纠缠态可以用来测量时间。<br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
将这两个粒子分开,可以更好地观察到纠缠的特殊性质。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫(把这当成一个思维实验,而不是实际的实验)。现在,如果我们测量其中一个粒子的特定特性(例如,自旋),得到一个结果,然后使用相同的标准测量另一个粒子(沿相同的轴自旋),我们发现第二个粒子的测量结果将与第一个粒子的测量结果相匹配(在互补意义上)粒子,因为它们的值是相反的<br />
In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts. The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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2013年,在意大利都灵的国家理查尔卡计量研究所(INRIM) ,研究人员对佩奇和伍特的想法进行了首次实验测试。他们的结果被解释为证实了对于内部观察者来说时间是一种涌现的现象,但正如惠勒-德威特方程所预测的那样,对于宇宙的外部观察者来说时间是不存在的。纠缠的方法是从因果时间箭头的角度出发,假设一个粒子被测量的原因决定了另一个粒子测量结果的效应。<br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a [[hidden variable theory]] (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
上述结果可能会或不会被认为是令人惊讶的。一个经典系统将显示出相同的性质,而[[隐藏变量理论]](见下文)肯定需要这样做,基于经典和量子力学中的角动量守恒。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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===Paradox矛盾===<br />
Based on AdS/CFT correspondence, Mark Van Raamsdonk suggested that spacetime arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time. Induced gravity can emerge from the entanglement first law.<br />
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基于 AdS/CFT对偶的理论,Mark Van Raamsdonk 提出时空是作为量子自由度的一种涌现现象而产生的,这种量子自由度是纠缠在一起的,生活在时空的边界上。诱导引力可以产生于纠缠第一定律。<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel [[faster than light]]) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the [[Copenhagen interpretation]], the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<ref>{{cite book|last1=Rupert W.|first1=Anderson|title=The Cosmic Compendium: Interstellar Travel|date=28 March 2015|publisher=The Cosmic Compendium|isbn=9781329022027|page=100|edition=First|url=https://books.google.com/books?id=JxauCQAAQBAJ&pg=PA100&lpg=PA100&dq=The+outcome+is+taken+to+be+random,+with+each+possibility+having+a+probability+of+50%25.+However,+if+both+spins+are+measured+along+the+same+axis,+they+are+found+to+be+anti-correlated.+This+means+that+the+random+outcome+of+the+measurement+made+on+one+particle+seems+to+have+been+transmitted+to+the+other,+so+that+it+can+make+the+%22right+choice%22+when+it+too+is+measured#v=onepage}}</ref><br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements [[spacelike]], hence, any causal effect connecting the events would have to travel faster than light. According to the principles of [[special relativity]], it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events {{math|''x''<sub>1</sub>}} and {{math|''x''<sub>2</sub>}} there are [[inertial frame]]s in which {{math|''x''<sub>1</sub>}} is first and others in which {{math|''x''<sub>2</sub>}} is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations. A well-known example is the Werner states that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables. Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<br />
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在媒体和流行科学中,量子非定域性经常被描述为等价于纠缠。虽然这对于纯二体量子态来说是正确的,但是一般来说纠缠只对于非局域关联是必要的,但是存在混合纠缠态,不产生这样的关联。一个众所周知的例子是 Werner 状态,它纠缠于 < math > p _ { sym } </math > 的某些值,但总是可以使用局部隐变量来描述。此外,研究还表明,对于任意数目的当事人,存在真正纠缠但承认局部模型的状态。<br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all distillable states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<br />
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上述关于局域模型存在性的证明假设一次只有一个量子态的副本可用。如果允许各方对这些状态的许多副本进行局部测量,那么许多表面上的局部状态(例如,量子位维尔纳状态)就不能再用局部模型来描述。对于所有的可提取态来说,情况尤其如此。然而,如果给定足够多的副本,是否所有纠缠态都成为非局域态,这仍然是一个有待解决的问题。<br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to quantum teleportation and to superdense coding, whereas non-locality is defined according to experimental statistics and is much more involved with the foundations and interpretations of quantum mechanics.<br />
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简而言之,双方共享的态的纠缠是必要的,但不足以使该态成为非局域态。重要的是要认识到纠缠通常被看作是一个代数概念,因为它是非定域性以及量子遥传和超密编码的先决条件,而非定域性是根据实验统计数据定义的,更多地涉及到基础和量子力学诠释。<br />
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=== Hidden variables theory ===<br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables".<ref>{{Cite news|url=https://www.scientificamerican.com/article/cosmic-test-bolsters-einsteins-ldquo-spooky-action-at-a-distance-rdquo/?WT.mc_id=SA_FB_PHYS_NEWS|title=Cosmic Test Bolsters Einstein's "Spooky Action at a Distance"|last=magazine|first=Elizabeth Gibney, Nature|newspaper=Scientific American|language=en|access-date=2017-02-04}}</ref> The state of the particles being measured contains some [[hidden-variable theory|hidden variables]], whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of quantum mechanics, including familiarity with the formalism and theoretical framework developed in the articles: bra–ket notation and mathematical formulation of quantum mechanics.<br />
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下面的小节适合那些对量子力学的形式和数学描述有良好工作知识的人,包括对文章中开发的形式主义和理论框架的熟悉: bra-ket 符号和量子力学的数学表述。<br />
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=== Violations of Bell's inequality ===<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the [[local realism|local realist]] or hidden variables view were correct, the results would always satisfy [[Bell's inequality]]. A [[Bell test experiments|number of experiments]] have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists.<ref>{{citation |author1=I. Gerhardt |author2=Q. Liu |author3=A. Lamas-Linares |author4=J. Skaar |author5=V. Scarani |author6=V. Makarov |author7=C. Kurtsiefer |year=2011 |title=Experimentally faking the violation of Bell's inequalities |journal=Phys. Rev. Lett. |volume=107 |issue=17 |page=170404 |arxiv=1106.3224 |doi=10.1103/PhysRevLett.107.170404 |bibcode=2011PhRvL.107q0404G |pmid=22107491|s2cid=16306493 }}</ref><ref>{{cite journal | last1 = Santos | first1 = E | year = 2004 | title = The failure to perform a loophole-free test of Bell's Inequality supports local realism | url = | journal = Foundations of Physics | volume = 34 | issue = 11| pages = 1643–1673 | doi=10.1007/s10701-004-1308-z|bibcode = 2004FoPh...34.1643S | s2cid = 123642560 }}</ref> When measurements of the entangled particles are made in moving [[special relativity|relativistic]] reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<ref>{{cite journal |author = H. Zbinden |title = Experimental test of nonlocal quantum correlations in relativistic configurations |journal = Phys. Rev. A |volume = 63 |issue = 2 |pages = 22111 |doi = 10.1103/PhysRevA.63.022111|year = 2001|arxiv = quant-ph/0007009 |bibcode = 2001PhRvA..63b2111Z |display-authors = 1 |last2 = Gisin |last3 = Tittel |s2cid = 44611890 |url = http://archive-ouverte.unige.ch/unige:37034 }}</ref><ref name=LG>Some of the history of both referenced Zbinden, et al. experiments is provided in Gilder, L., ''The Age of Entanglement'', Vintage Books, 2008, pp. 321–324.</ref><br />
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Consider two arbitrary quantum systems and , with respective Hilbert spaces and . The Hilbert space of the composite system is the tensor product<br />
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考虑两个任意的量子系统和,分别具有希尔伯特空间和。复合系统的 Hilbert 空间是张量积<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are [[Incompatible observables|incompatible]] in the sense that these measurements' maximum simultaneous precision is constrained by the [[uncertainty principle]]. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations,<ref>{{cite journal|last1=Cirel'son|first1=B. S.|title=Quantum generalizations of Bell's inequality|journal=Letters in Mathematical Physics|volume=4|issue=2|pages=93–100| year=1980|doi=10.1007/BF00417500|bibcode=1980LMaPh...4...93C|s2cid=120680226}}</ref> and thus entanglement is a fundamentally non-classical phenomenon.<br />
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Entanglement is required to preserve the [[Uncertainty principle]], as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态 < math > scriptstyle | psi rangle _ a </math > ,而第二个系统处于状态 < math > scriptstyle | phi rangle _ b </math > ,则复合系统的状态为<br />
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=== Other types of experiments ===<br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time.<ref name="Xiao-song2012">{{cite journal |author=Xiao-song Ma, Stefan Zotter, Johannes Kofler, Rupert Ursin, Thomas Jennewein, Časlav Brukner & Anton Zeilinger |title=Experimental delayed-choice entanglement swapping |journal=Nature Physics |volume=8 |issue=6 |pages=480–485 |date=26 April 2012 |doi=10.1038/nphys2294|arxiv = 1203.4834 |bibcode = 2012NatPh...8..480M |last2=Zotter |last3=Kofler |last4=Ursin |last5=Jennewein |last6=Brukner |last7=Zeilinger |s2cid=119208488 }}</ref><ref>{{cite journal | last1 = Megidish | first1 = E. | last2 = Halevy | first2 = A. | last3 = Shacham | first3 = T. | last4 = Dvir | first4 = T. | last5 = Dovrat | first5 = L. | last6 = Eisenberg | first6 = H. S. | year = 2013 | title = Entanglement Swapping between Photons that have Never Coexisted | url = | journal = Physical Review Letters | volume = 110 | issue = 21| page = 210403| doi=10.1103/physrevlett.110.210403|arxiv = 1209.4191 |bibcode = 2013PhRvL.110u0403M | pmid=23745845| s2cid = 30063749 }}</ref> The authors claimed that this result was achieved by [[Quantum teleportation#Entanglement swapping|entanglement swapping]] between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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<math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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[数学][数学][数学]<br />
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In three independent experiments in 2013 it was shown that [[classical physics|classically communicated]] [[separable state|separable quantum states]] can be used to carry entangled states.<ref>{{cite web|url=http://physicsworld.com/cws/article/news/2013/dec/11/classical-carrier-could-create-entanglement |title=Classical carrier could create entanglement |publisher=physicsworld.com |accessdate=2014-06-14|date=2013-12-11 }}</ref> The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<ref>{{cite web | url=http://hansonlab.tudelft.nl/loophole-free-bell-test/ | title=Loophole-free Bell test &#124; Ronald Hanson | access-date=24 October 2015 | archive-url=https://web.archive.org/web/20180704082456/http://hansonlab.tudelft.nl/loophole-free-bell-test/ | archive-date=4 July 2018 | url-status=dead }}</ref><br />
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States of the composite system that can be represented in this form are called separable states, or product states.<br />
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可以用这种形式表示的复合系统状态称为可分状态或乘积状态。<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<ref>{{Cite journal|url=http://www.nature.com/news/entangled-photons-make-a-picture-from-a-paradox-1.15781|title=Entangled photons make a picture from a paradox|journal=Nature|accessdate=13 October 2014|doi=10.1038/nature.2014.15781|year=2014|last1=Gibney|first1=Elizabeth|s2cid=124976589}}</ref><br />
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Not all states are separable states (and thus product states). Fix a basis <math>\scriptstyle \{|i \rangle_A\}</math> for and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for . The most general state in is of the form<br />
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并非所有状态都是可分状态(因此也就是乘积状态)。修复一个基础 < math > scriptstyle { | i rangle _ a } </math > for 和一个基础 < math > scriptstyle { | j rangle _ b } </math > for。最普遍的状态是形式<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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<math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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[数学] | psi rangle { AB } = sum { i,j } c { ij } | i rangle _ a otimes | j rangle _ b </math > 。<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<ref>{{Cite journal|last=Rozatkar|first=Gaurav|date=2018-08-16|title=Demonstration of quantum entanglement|url=https://osf.io/g8bpj/|journal=OSF|language=en}}</ref><br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > ,那么这种状态是可分的,因此 < math scriptstyle c { ij } = c ^ a _ ic ^ b _ j,</math > 产生 < math scriptstyle | psi rangle _ a = sum { i } c ^ a _ { i } | i } | i _ a </math > 和 < math > phi scriptstyle | b = sum { j } | j } | j rangle b = sum { j }。如果对于任何向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > 至少对于一对坐标 < math > scriptstyle c ^ a _ i,c ^ b _ j </math > 我们有 < math > scriptstyle c _ { ij } neq c ^ a _ ic ^ b _ j。如果一种状态是不可分割的,那么它被称为“纠缠态”。<br />
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=== Mystery of time ===<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of , the following is an entangled state:<br />
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例如,给定两个基向量{ | 0 rangle _ a,| 1 rangle _ a } </math > 和两个基向量{ | 0 rangle _ b,| 1 rangle _ b } </math > ,下面是一个纠缠态:<br />
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There have been suggestions to look at the concept of time as an [[emergent phenomenon]] that is a side effect of quantum entanglement.<ref>{{Cite journal|title= Time from quantum entanglement: an experimental illustration|arxiv=1310.4691|bibcode = 2014PhRvA..89e2122M |doi = 10.1103/PhysRevA.89.052122|volume=89|issue= 5|pages=052122|journal=Physical Review A|year=2014 | last1 = Moreva | first1 = Ekaterina|s2cid=118638346}}</ref><ref>{{cite web|url=https://www.newscientist.com/article/dn24473-entangled-toy-universe-shows-time-may-be-an-illusion.html#.U8_-ApSSx2A|title=Entangled toy universe shows time may be an illusion|publisher=|accessdate=13 October 2014}}</ref><br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by [[Don Page (physicist)|Don Page]] and [[William Wootters]] in 1983.<ref>David Deutsch, The Beginning of infinity. Page 299</ref><br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right)<br />
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The [[Wheeler–DeWitt equation]] that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<ref name="medium.com">{{cite web|url=https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933|title=Quantum Experiment Shows How Time 'Emerges' from Entanglement|website=Medium|accessdate=13 October 2014|date=2013-10-23}}</ref><br />
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If the composite system is in this state, it is impossible to attribute to either system or system a definite pure state. Another way to say this is that while the von Neumann entropy of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry. The above example is one of four Bell states, which are (maximally) entangled pure states (pure states of the space, but which cannot be separated into pure states of each and ).<br />
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如果组合系统处于这种状态,就不可能给任何一个系统或系统一个确定的纯状态。另一种说法是,尽管整个状态的冯纽曼熵为零(对于任何纯状态都是如此) ,但子系统的熵大于零。从这个意义上说,这两个系统是“纠缠”的。这对干涉测量法有具体的经验影响。上面的例子是四个贝尔态之一,它们是(最大)纠缠纯态(空间的纯态,但不能分离成每个和的纯态)。<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted{{by whom|date=August 2020}} to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts.<ref name="medium.com"/><br />
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Now suppose Alice is an observer for system , and Bob is an observer for system . If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of , there are two possible outcomes, occurring with equal probability:<br />
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现在假设 Alice 是系统的观察者,而 Bob 是系统的观察者。如果在上面给出的纠缠态中,爱丽丝在[ | 0 rangle,| 1 rangle ] </math 本征基中进行测量,有两种可能的结果,发生的概率相等:<br />
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=== Source for the arrow of time ===<br />
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Physicist [[Seth Lloyd]] says that [[quantum uncertainty]] gives rise to entanglement, the putative source of the [[arrow of time]]. According to Lloyd; "The arrow of time is an arrow of increasing correlations."<ref>{{Cite journal|url=https://www.wired.com/2014/04/quantum-theory-flow-time/|title=New Quantum Theory Could Explain the Flow of Time|journal=Wired|accessdate=13 October 2014|date=2014-04-25|last1=Wolchover|first1=Natalie}}</ref> The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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Alice 测量0,系统的状态崩溃为 < math > scriptstyle | 0 rangle _ a | 1 rangle _ b </math > 。<br />
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Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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Alice 测量1,系统的状态崩溃为 < math > scriptstyle | 1 rangle _ a | 0 rangle _ b </math > 。<br />
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=== Emergent gravity ===<br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system has been altered by Alice performing a local measurement on system . This remains true even if the systems and are spatially separated. This is the foundation of the EPR paradox.<br />
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如果前者发生,那么 Bob 在相同基础上执行的任何后续测量都将返回1。如果出现后一种情况,(Alice 度量1) ,那么 Bob 的度量将确定返回0。因此,Alice 对系统进行了本地测量,从而对系统进行了更改。即使系统和空间上是分开的,这也是正确的。这就是 EPR 悖论的基础。<br />
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Based on [[AdS/CFT correspondence]], [[Mark Van Raamsdonk]] suggested that [[spacetime]] arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time.<ref>{{Cite journal|last=Van Raamsdonk|first=Mark|date=2010-06-19|title=Building up spacetime with quantum entanglement|journal=General Relativity and Gravitation|language=en|volume=42|issue=10|pages=2323–2329|doi=10.1007/s10714-010-1034-0|issn=0001-7701|arxiv=1005.3035|bibcode=2010GReGr..42.2323V}}</ref> [[Induced gravity]] can emerge from the entanglement first law.<ref>{{Cite journal|last1=Lee|first1=Jae-Weon|last2=Kim|first2=Hyeong-Chan|last3=Lee|first3=Jungjai|date=2013|title=Gravity from quantum information|journal=Journal of the Korean Physical Society|language=en|volume=63|issue=5|pages=1094–1098|doi=10.3938/jkps.63.1094|issn=0374-4884|arxiv=1001.5445|bibcode=2013JKPS...63.1094L|s2cid=118494859}}</ref><ref>{{cite arxiv|last1=Swingle|first1=Brian|last2=Van Raamsdonk|first2=Mark|date=2014-05-12|title=Universality of Gravity from Entanglement|eprint=1405.2933 |class=hep-th}}</ref><br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem.<br />
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爱丽丝的测量结果是随机的。Alice 不能决定将组合系统折叠到哪个状态,因此不能通过作用于她的系统将信息传递给 Bob。因此,在这个特定的方案中,因果关系被保留了下来。关于一般的论点,请参阅不交流定理。<br />
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== Non-locality and entanglement ==<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations.<ref name="Brunner-RMP2014">{{cite journal |title=Bell nonlocality |author1=Nicolas Brunner |author2=Daniel Cavalcanti |author3=Stefano Pironio |author4=Valerio Scarani |author5=Stephanie Wehner |journal=Rev. Mod. Phys. |volume=86 |issue=2 |pages=419–478 |date=2014 |doi=10.1103/RevModPhys.86.419 |arxiv=1303.2849|bibcode=2014RvMP...86..419B |s2cid=119194006 }}</ref> A well-known example is the [[Werner state]]s that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables.<ref name=werner1989>{{cite journal | last = Werner| first = R.F. | title = Quantum States with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model | journal = [[Physical Review A]] | volume = 40| pages = 4277–4281 | year = 1989 |doi=10.1103/PhysRevA.40.4277 | pmid=9902666 | issue=8|bibcode = 1989PhRvA..40.4277W }}</ref> Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<ref>{{cite journal|author=R. Augusiak, M. Demianowicz, J. Tura and A. Acín |title=Entanglement and Nonlocality are Inequivalent for Any Number of Parties |journal=Phys. Rev. Lett. |volume=115 |issue=3 |pages=030404 |year=2015 |arxiv=1407.3114 |doi=10.1103/PhysRevLett.115.030404|pmid=26230773 |hdl=2117/78836 |bibcode=2015PhRvL.115c0404A |s2cid=29758483 }}</ref><br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all [[entanglement distillation|distillable]] states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<ref>{{cite journal |title=Disproving the Peres conjecture: Bell nonlocality from bipartite bound entanglement |authors=Tamas Vértesi, Nicolas Brunner|year=2014 |journal=Nature Communications |volume=5 |issue=5297|page=5297 |doi=10.1038/ncomms6297 |pmid=25370352|arxiv=1405.4502 |s2cid=5135148}}</ref><br />
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As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a density matrix, which is a positive-semidefinite matrix, or a trace class when the state space is infinite-dimensional, and has trace 1. Again, by the spectral theorem, such a matrix takes the general form:<br />
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如上所述,量子系统的状态是由希尔伯特空间中的单位向量给出的。更一般地说,如果一个人对系统的了解较少,那么他就称之为“集合” ,并用密度矩阵来描述它,密度矩阵是正半定矩阵,或者当状态空间是无限维且迹1时,用迹类来描述它。同样的,在谱定理,这样的矩阵采取了一般的形式:<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to [[quantum teleportation]] and to [[superdense coding]], whereas non-locality is defined according to experimental statistics and is much more involved with the [[Quantum foundations|foundations]] and [[interpretations of quantum mechanics]].<ref>In the literature "non-locality" is sometimes used to characterize concepts that differ from the non-existence of a local hidden variable model, e.g., whether states can be distinguished by local measurements and which can occur also for non-entangled states (see, e.g., {{cite journal |authors=Charles H. Bennett, David P. DiVincenzo, Christopher A. Fuchs, Tal Mor, Eric Rains, Peter W. Shor, John A. Smolin, and William K. Wootters |title=Quantum nonlocality without entanglement |journal=Phys. Rev. A |volume=59 |issue=2 |pages=1070–1091 |year=1999 |doi=10.1103/PhysRevA.59.1070 |arxiv= quant-ph/9804053|bibcode=1999PhRvA..59.1070B |s2cid=15282650 }}). This non-standard use of the term is not discussed here.</ref><br />
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<math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
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我不知道,我不知道,我不知道<br />
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== Quantum mechanical framework ==<br />
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where the w<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret as representing an ensemble where is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need density matrices to represent the state.<br />
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其中 w < sub > i </sub > 是正值概率(和为1) ,向量是单位向量,在无限维情况下,我们取这些状态的闭包为迹范数。我们可以解释为代表一个集合,其中集合的状态是 < math > | alpha _ i rangle </math > 。当一个混合状态的秩为1时,它就描述了一个纯系综。当量子系统的状态信息少于总量时,我们需要密度矩阵来表示状态。<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of [[quantum mechanics]], including familiarity with the formalism and theoretical framework developed in the articles: [[bra–ket notation]] and [[mathematical formulation of quantum mechanics]].<br />
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Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits electrons towards an observer. The electrons' Hilbert spaces are identical. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with spins aligned in the positive direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
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在实验上,可以实现如下的混合集成。考虑一个“黑盒子”装置,它向观察者喷射电子。电子的希尔伯特空间是相同的。该装置可能产生全部处于相同状态的电子; 在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以在不同的状态下产生电子。例如,它可以产生两个电子群: 一个是状态 < math > | mathbf { z } + rangle </math > 的正方向自旋,另一个是状态 < math > | mathbf { y }-rangle </math > 的负方向自旋。通常,这是一个混合集合,因为可以有任意数量的总体,每个总体对应不同的状态。<br />
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=== Pure states ===<br />
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Consider two arbitrary quantum systems {{mvar|A}} and {{mvar|B}}, with respective [[Hilbert space]]s {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}. The Hilbert space of the composite system is the [[tensor product]]<br />
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Following the definition above, for a bipartite composite system, mixed states are just density matrices on . That is, it has the general form<br />
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根据上面的定义,对于二部复合系统,混合态仅仅是上面的密度矩阵。也就是说,它有一般的形式<br />
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: <math> H_A \otimes H_B.</math><br />
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<math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
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[数学] rho = sum { i } w _ i 左[ sum _ { j } bar { c }{ ij }(| alpha _ { ij } rangle otimes | beta _ { ij } rangle)右]左[ sum _ k c _ { ik }(langle alpha _ ik } | otimes langle beta _ { ik } | 右]<br />
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</math><br />
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数学<br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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where the w<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
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其中 w < sub > i </sub > 是正值概率,< math > sum _ j | c _ { ij } | ^ 2 = 1 </math > ,向量是单位向量。这是自伴和正的,并且有迹1。<br />
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: <math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<br />
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从纯粹情形扩展可分性的定义,我们说混合状态是可分的,如果它可以写成<br />
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States of the composite system that can be represented in this form are called [[separable state]]s, or [[product state]]s.<br />
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<math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
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(数学) rho = sum i w i rho i ^ a times rho i ^ b,(数学)<br />
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Not all states are separable states (and thus product states). Fix a [[basis (linear algebra)|basis]] <math>\scriptstyle \{|i \rangle_A\}</math> for {{mvar|H<sub>A</sub>}} and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for {{mvar|H<sub>B</sub>}}. The most general state in {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} is of the form<br />
<br />
<br />
<br />
where the are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems and respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
其中的正值概率和 rho _ i ^ a </math > 的和 rho _ i ^ b </math > 的本身是子系统和子系统上的混合状态(密度算符)。换句话说,如果一个状态是不相关状态或乘积状态上的概率分布,则该状态是可分的。通过将密度矩阵写成纯系综和并进行扩展,我们可以假定,不失一般性和数学本身就是纯系综。如果一个状态不可分离,则称其为纠缠态。<br />
<br />
: <math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be NP-hard. For the and cases, a necessary and sufficient criterion for separability is given by the famous Positive Partial Transpose (PPT) condition.<br />
<br />
一般来说,要判断一个混合态是否是纠缠态是很困难的。一般的二部格被证明是 np 困难的。对于和种情形,利用著名的正偏转子(PPT)条件给出了可分性的一个充要条件。<br />
<br />
This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
<br />
<br />
<br />
For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of {{mvar|H<sub>A</sub>}} and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of {{mvar|H<sub>B</sub>}}, the following is an entangled state:<br />
<br />
The idea of a reduced density matrix was introduced by Paul Dirac in 1930. Consider as above systems and each with a Hilbert space . Let the state of the composite system be<br />
<br />
约化密度矩阵的概念是由保罗 · 狄拉克在1930年提出的。考虑以上系统,每个系统都有一个希尔伯特空间。设复合系统的状态为<br />
<br />
<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
<br />
<math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
[数学] | Psi 在 h _ a 和 h _ b 之间。数学<br />
<br />
<br />
<br />
If the composite system is in this state, it is impossible to attribute to either system {{mvar|A}} or system {{mvar|B}} a definite [[pure state]]. Another way to say this is that while the [[von Neumann entropy]] of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry.<ref name="JaegerEtAl95">{{cite journal |author=Jaeger G, Shimony A, Vaidman L |title=Two Interferometric Complementarities |journal=Phys. Rev. |volume=51 |issue=1 |pages=54–67 |year=1995 |doi=10.1103/PhysRevA.51.54|pmid=9911555 |bibcode = 1995PhRvA..51...54J |last2=Shimony |last3=Vaidman }}</ref> The above example is one of four [[Bell states]], which are (maximally) entangled pure states (pure states of the {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} space, but which cannot be separated into pure states of each {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}).<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system . However, it still is possible to associate a density matrix. Let<br />
<br />
如上所述,通常没有办法将纯状态关联到组件系统。然而,仍然有可能将密度矩阵联系起来。让<br />
<br />
<br />
<br />
Now suppose Alice is an observer for system {{mvar|A}}, and Bob is an observer for system {{mvar|B}}. If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of {{mvar|A}}, there are two possible outcomes, occurring with equal probability:<ref name=nielchuang>{{cite book| last = Nielsen | first = Michael A. |author2=Chuang, Isaac L. | year = 2000 | title = Quantum Computation and Quantum Information | publisher = [[Cambridge University Press]] | pages = 112–113| isbn = 978-0-521-63503-5}}</ref><br />
<br />
<math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
我不知道,我不知道,我不知道。<br />
<br />
<br />
<br />
# Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
<br />
which is the projection operator onto this state. The state of is the partial trace of over the basis of system :<br />
<br />
也就是这个状态的投影操作符。状态是系统基础上的部分轨迹:<br />
<br />
# Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
<br />
<br />
<br />
<math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
(| Psi rangle langle Psi | right) | j rangle b = hbox { Tr } _ b; rho _ t. </math > <br />
<br />
If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system {{mvar|B}} has been altered by Alice performing a local measurement on system {{mvar|A}}. This remains true even if the systems {{mvar|A}} and {{mvar|B}} are spatially separated. This is the foundation of the [[EPR paradox]].<br />
<br />
<br />
<br />
is sometimes called the reduced density matrix of on subsystem . Colloquially, we "trace out" system to obtain the reduced density matrix on .<br />
<br />
有时被称为子系统的约化密度矩阵。通俗地说,我们“追踪”系统,以获得约化密度矩阵。<br />
<br />
The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see [[no-communication theorem]].<br />
<br />
<br />
<br />
For example, the reduced density matrix of for the entangled state<br />
<br />
例如,纠缠态的约化密度矩阵<br />
<br />
=== Ensembles ===<br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a [[density matrix]], which is a [[positive-semidefinite matrix]], or a [[trace class]] when the state space is infinite-dimensional, and has trace 1. Again, by the [[spectral theorem]], such a matrix takes the general form:<br />
<br />
<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right) ,</math > <br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
discussed above is<br />
<br />
以上所讨论的是<br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors {{mvar| α<sub>i</sub>}} are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret {{mvar|ρ}} as representing an ensemble where {{mvar|w<sub>i</sub>}} is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need [[#Reduced density matrices|density matrices]] to represent the state.<br />
<br />
<math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
左(| 0 rangle 0 | a + | 1 rangle 1 | a right) </math > <br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits [[electron]]s towards an observer. The electrons' Hilbert spaces are [[identical particles|identical]]. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with [[spin (physics)|spins]] aligned in the positive {{math|'''z'''}} direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative {{math|'''y'''}} direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
这表明,正如预期的那样,一个纠缠纯系综的约化密度矩阵是一个混合系综。同样不足为奇的是,上面讨论的纯乘积态的密度矩阵<br />
<br />
<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}}. That is, it has the general form<br />
<br />
<math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
我不知道,但是我知道,我知道。<br />
<br />
<br />
<br />
: <math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
一般情况下,二体纯态 ρ 纠缠当且仅当其约化态是混合态而不是纯态。<br />
<br />
</math><br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional AKLT spin chain: the ground state can be divided into a block and an environment. The reduced density matrix of the block is proportional to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
在不同的基态自旋链中显式计算了约化密度矩阵。一维 AKLT 自旋链就是一个例子: 基态可以分为一个区块和一个环境。块的约化密度矩阵与另一个哈密顿量的简并基态成正比。<br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<ref name=Laloe>{{citation|last=Laloe|first=Franck|year=2001|title=Do We Really Understand Quantum Mechanics|journal=American Journal of Physics |volume=69 |issue=6|pages=655–701 |arxiv=quant-ph/0209123 |bibcode=2001AmJPh..69..655L |doi=10.1119/1.1356698}}</ref>{{rp|131–132}}<br />
<br />
The reduced density matrix also was evaluated for XY spin chains, where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence in this case.<br />
<br />
并对 XY 自旋链的全秩约化密度矩阵进行了计算。证明了在热力学极限中,大块自旋的约化密度矩阵的谱在这种情况下是一个精确的几何序列。<br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary quantum operations can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called LOCC (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<br />
<br />
在量子信息理论中,纠缠态被认为是一种“资源” ,即制造成本高昂的物质,并且可以实现有价值的转换。这种观点最为明显的背景是“遥远的实验室” ,即两个标记为“ a”和“ b”的量子系统,其中每个系统都可以执行任意的量子操作,但它们之间不存在量子力学相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为 LOCC 的操作(局部操作和经典通信)。这些操作不允许在系统 a 和系统 b 之间产生纠缠态。但是如果给 a 和 b 提供了纠缠态,那么这些纠缠态和 LOCC 操作一起可以产生更大类的变换。例如,a 的一个量子比特和 b 的一个量子比特之间的相互作用可以通过首先将 a 的量子比特传送到 b,然后让 b 的量子比特和 b 的量子比特相互作用(这现在是一个 LOCC 操作,因为两个量子比特都在 b 的实验室里) ,然后再传送量子比特回到 a。两个量子比特的最大纠缠态在这个过程中被用完。因此,纠缠态是一种资源,它能够在只有 LOCC 可用的情况下实现量子相互作用(或量子通道) ,但是在这个过程中会被消耗掉。在其他应用中,纠缠态可以被看作是一种资源,例如,私人通信或者区分量子态。<br />
<br />
where the {{mvar|w<sub>i</sub>}} are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems {{mvar|A}} and {{mvar|B}} respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be [[NP-hard]].<ref>{{Cite book |author=Gurvits L |title=Proceedings of the thirty-fifth ACM symposium on Theory of computing - STOC '03 |chapter=Classical deterministic complexity of Edmonds' Problem and quantum entanglement |journal=Proceedings of the Thirty-fifth Annual ACM Symposium on Theory of Computing |year=2003 |doi=10.1145/780542.780545 |page=10 |isbn=978-1-58113-674-6|arxiv=quant-ph/0303055 |s2cid=5745067 }}</ref> For the {{math|2 × 2}} and {{math|2 × 3}} cases, a necessary and sufficient criterion for separability is given by the famous [[Peres-Horodecki criterion|Positive Partial Transpose (PPT)]] condition.<ref>{{cite journal |author=Horodecki M, Horodecki P, Horodecki R |title=Separability of mixed states: necessary and sufficient conditions |journal=Physics Letters A |volume=223 |issue=1 |page=210 |year=1996 |doi=10.1016/S0375-9601(96)00706-2 |bibcode=1996PhLA..223....1H|arxiv = quant-ph/9605038 |last2=Horodecki |last3=Horodecki |citeseerx=10.1.1.252.496 |s2cid=10580997 }}</ref><br />
<br />
<br />
<br />
=== Reduced density matrices ===<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
<br />
在这一节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的度量。<br />
<br />
The idea of a reduced density matrix was introduced by [[Paul Dirac]] in 1930.<ref>{{cite journal|doi=10.1017/S0305004100016108|title=Note on Exchange Phenomena in the Thomas Atom|year=2008|last1=Dirac|first1=P. A. M.|journal=Mathematical Proceedings of the Cambridge Philosophical Society| volume=26| issue=3|page=376|bibcode=1930PCPS...26..376D|url=https://www.cambridge.org/core/services/aop-cambridge-core/content/view/6C5FF7297CD96F49A8B8E9E3EA50E412/S0305004100016108a.pdf/div-class-title-note-on-exchange-phenomena-in-the-thomas-atom-div.pdf}}</ref> Consider as above systems {{mvar|A}} and {{mvar|B}} each with a Hilbert space {{mvar|H<sub>A</sub>, H<sub>B</sub>}}. Let the state of the composite system be<br />
<br />
<br />
<br />
: <math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.<br />
<br />
二分子2能级纯态的冯纽曼熵与本征值的图。当本征值为5时,冯纽曼熵处于最大值,相当于最大纠缠度。<br />
<br />
<br />
<br />
In classical information theory , the Shannon entropy, is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<br />
<br />
在经典的信息论中,香农熵,是与概率分布相关联的,如下:<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system {{mvar|A}}. However, it still is possible to associate a density matrix. Let<br />
<br />
<br />
<br />
<math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
<br />
[ math ] h (p _ 1,cdots,p _ n) =-sum _ i p _ i log _ 2 p _ i. [ math ]<br />
<br />
: <math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
<br />
<br />
Since a mixed state is a probability distribution over an ensemble, this leads naturally to the definition of the von Neumann entropy:<br />
<br />
由于混合状态是一个概率分布超过一个总体,这自然导致了冯纽曼熵的定义:<br />
<br />
which is the [[projection operator]] onto this state. The state of {{mvar|A}} is the [[partial trace]] of {{mvar|ρ<sub>T</sub>}} over the basis of system {{mvar|B}}:<br />
<br />
<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
<br />
(rho) =-hbox { Tr } left (rho log _ 2{ rho } right) <br />
<br />
: <math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
<br />
<br />
In general, one uses the Borel functional calculus to calculate a non-polynomial function such as . If the nonnegative operator acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
<br />
一般来说,人们使用 Borel 函数演算来计算一个非多项式函数,如。如果非负算子作用于有限维希尔伯特空间,并且具有本征值 < math > lambda _ 1,那么 cdots,lambda _ n </math > ,结果只不过是具有相同本征向量的算子,但本征值 < math > log _ 2(lambda _ 1) ,点,log _ 2(lambda _ n) </math > 。那么香农熵就是:<br />
<br />
{{mvar|ρ<sub>A</sub>}} is sometimes called the reduced density matrix of {{mvar|ρ}} on subsystem {{mvar|A}}. Colloquially, we "trace out" system {{mvar|B}} to obtain the reduced density matrix on {{mvar|A}}.<br />
<br />
<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
<br />
(rho) =-hbox { Tr } left (rho log 2{ rho } right) =-sum _ i lambda _ i log _ 2 lambda _ i </math > .<br />
<br />
For example, the reduced density matrix of {{mvar|A}} for the entangled state<br />
<br />
<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
<br />
因为一个概率为0的事件不应该对熵有贡献,并且假设<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
<br />
<br />
<math> \lim_{p \to 0} p \log p = 0,</math><br />
<br />
[ math > lim _ { p to 0} p log p = 0,</math > <br />
<br />
discussed above is<br />
<br />
<br />
<br />
the convention 0}} is adopted. This extends to the infinite-dimensional case as well: if has spectral resolution<br />
<br />
约定0}被采用。这也延伸到无限维情况: 如果有光谱分辨率<br />
<br />
: <math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
<br />
<br />
<math> \rho = \int \lambda d P_{\lambda},</math><br />
<br />
数学,数学,数学<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of {{mvar|A}} for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
<br />
<br />
assume the same convention when calculating<br />
<br />
在计算时采用相同的约定<br />
<br />
: <math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
<br />
<br />
<math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
<br />
[数学] rho log 2 rho = int lambda log 2 lambda d { lambda }<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
<br />
<br />
As in statistical mechanics, the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is (which can be shown to be the maximum entropy for mixed states).<br />
<br />
就像统计力学一样,系统的不确定性(微观状态的数量)越多,熵就越大。例如,任何纯态的熵都为零,这并不奇怪,因为处于纯态的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个的熵都是(混合态的最大熵)。<br />
<br />
=== Two applications that use them ===<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional [[AKLT Model|AKLT spin chain]]:<ref name="Fan2004">{{cite journal | doi = 10.1103/PhysRevLett.93.227203 | title = Entanglement in a Valence-Bond Solid State | journal = Physical Review Letters | year = 2004 | first = H | last = Fan | page = 227203 |author2=Korepin V |author3=Roychowdhury V | volume = 93 | issue = 22 | pmid = 15601113 |arxiv=quant-ph/0406067 | bibcode=2004PhRvL..93v7203F| s2cid = 28587190 }}</ref> the ground state can be divided into a block and an environment. The reduced density matrix of the block is [[Proportionality (mathematics)|proportional]] to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist. If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
<br />
熵提供了一个可以用来量化纠缠的工具,尽管还存在其他的纠缠度量方法。如果整个系统是纯系统,则可以用一个子系统的熵来衡量其与其他子系统的纠缠程度。<br />
<br />
The reduced density matrix also was evaluated for [[Heisenberg model (quantum)|XY spin chains]], where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence<ref>{{cite journal| doi=10.1007/s11128-010-0197-7|arxiv=1002.2931|title=Spectrum of the density matrix of a large ''block of'' spins of the XY model in one dimension| year=2010|last1=Franchini|first1=F.|last2=Its|first2=A. R.|last3=Korepin|first3=V. E.|last4=Takhtajan|first4=L. A.|journal=Quantum Information Processing|volume=10|issue=3|pages=325–341|s2cid=6683370}}</ref> in this case.<br />
<br />
<br />
<br />
For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
<br />
对于两体纯态,减少态的冯纽曼熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的特定公理的态家族中唯一的函数。<br />
<br />
=== Entanglement as a resource ===<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary [[quantum operation]]s can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called [[LOCC]] (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<ref name="horodecki2007" /><br />
<br />
It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/n,...,1/n}. Therefore, a bipartite pure state is said to be a maximally entangled state if the reduced state of is the diagonal matrix<br />
<br />
一个经典的结果是,香农熵在均匀概率分布{1/n,... ,1/n }处达到最大值。因此,如果二分纯态的约化态是对角矩阵,则称二分纯态为最大纠缠态<br />
<br />
<br />
<br />
=== Classification of entanglement ===<br />
<br />
<math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
<br />
< math > begin { bmatrix } frac {1}{ n } & & ddots & frac {1}{ n } end { bmatrix } . </math > <br />
<br />
Not all quantum states are equally valuable as a resource. To quantify this value, different [[Quantum entanglement#Entanglement measures|entanglement measures]] (see below) can be used, that assign a numerical value to each quantum state. However, it is often interesting to settle for a coarser way to compare quantum states. This gives rise to different classification schemes. Most entanglement classes are defined based on whether states can be converted to other states using LOCC or a subclass of these operations. The smaller the set of allowed operations, the finer the classification. Important examples are:<br />
<br />
* If two states can be transformed into each other by a local unitary operation, they are said to be in the same ''LU class''. This is the finest of the usually considered classes. Two states in the same LU class have the same value for entanglement measures and the same value as a resource in the distant-labs setting. There is an infinite number of different LU classes (even in the simplest case of two qubits in a pure state).<ref name="GRB1998">>{{cite journal |author1=Grassl, M. |author2=Rötteler, M. |author3=Beth, T. |title=Computing local invariants of quantum-bit systems |journal=Phys. Rev. A |volume=58 |issue=3 |pages=1833–1839 |year=1998 |doi=10.1103/PhysRevA.58.1833 |arxiv=quant-ph/9712040|bibcode=1998PhRvA..58.1833G |s2cid=15892529 }}</ref><ref name="Kraus2010">{{cite journal |author=B. Kraus |authorlink=Barbara Kraus|title=Local unitary equivalence of multipartite pure states |journal=Phys. Rev. Lett. |volume=104 |issue=2 |page=020504 |year=2010 |arxiv=0909.5152 |doi=10.1103/PhysRevLett.104.020504|pmid=20366579 |bibcode=2010PhRvL.104b0504K|s2cid=29984499}}</ref><br />
<br />
For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
<br />
对于混合态,简化冯纽曼熵并不是唯一合理的纠缠度量。<br />
<br />
* If two states can be transformed into each other by local operations including measurements with probability larger than 0, they are said to be in the same 'SLOCC class' ("stochastic LOCC"). Qualitatively, two states <math>\rho_1</math> and <math>\rho_2</math> in the same SLOCC class are equally powerful (since I can transform one into the other and then do whatever it allows me to do), but since the transformations <math>\rho_1\to\rho_2</math> and <math>\rho_2\to\rho_1</math> may succeed with different probability, they are no longer equally valuable. E.g., for two pure qubits there are only two SLOCC classes: the entangled states (which contains both the (maximally entangled) Bell states and weakly entangled states like <math>|00\rangle+0.01|11\rangle</math>) and the separable ones (i.e., product states like <math>|00\rangle</math>).<ref>{{cite journal |author=M. A. Nielsen |title=Conditions for a Class of Entanglement Transformations |journal=Phys. Rev. Lett. |volume=83 |issue=2 |page=436 |year=1999 |doi=10.1103/PhysRevLett.83.436 |arxiv=quant-ph/9811053|bibcode=1999PhRvL..83..436N |s2cid=17928003 }}</ref><ref name="GoWa2010">{{cite journal |authors=Gour, G. & Wallach, N. R. |title=Classification of Multipartite Entanglement of All Finite Dimensionality |journal=Phys. Rev. Lett. |volume=111 |issue=6 |page=060502 |year=2013 |doi=10.1103/PhysRevLett.111.060502 |pmid=23971544 |arxiv=1304.7259|bibcode=2013PhRvL.111f0502G |s2cid=1570745 }}</ref><br />
<br />
* Instead of considering transformations of single copies of a state (like <math>\rho_1\to\rho_2</math>) one can define classes based on the possibility of multi-copy transformations. E.g., there are examples when <math>\rho_1\to\rho_2</math> is impossible by LOCC, but <math>\rho_1\otimes\rho_1\to\rho_2</math> is possible. A very important (and very coarse) classification is based on the property whether it is possible to transform an arbitrarily large number of copies of a state <math>\rho</math> into at least one pure entangled state. States that have this property are called [[Entanglement distillation|distillable]]. These states are the most useful quantum states since, given enough of them, they can be transformed (with local operations) into any entangled state and hence allow for all possible uses. It came initially as a surprise that not all entangled states are distillable, those that are not are called '[[Bound entanglement|bound entangled]]'.<ref name="HHH97">{{cite journal |author1=Horodecki, M. |author2=Horodecki, P. |author3=Horodecki, R. |title=Mixed-state entanglement and distillation: Is there a ''bound'' entanglement in nature? |journal=Phys. Rev. Lett. |volume=80 |issue=1998 |pages=5239–5242 |year=1998 |arxiv=quant-ph/9801069|doi=10.1103/PhysRevLett.80.5239 |bibcode=1998PhRvL..80.5239H |s2cid=111379972 }}</ref><ref name="horodecki2007" /><br />
<br />
As an aside, the information-theoretic definition is closely related to entropy in the sense of statistical mechanics (comparing the two definitions in the present context, it is customary to set the Boltzmann constant 1}}). For example, by properties of the Borel functional calculus, we see that for any unitary operator ,<br />
<br />
顺便说一句,信息论的定义与统计力学意义上的熵密切相关(比较在当前语境下的两个定义,通常设置波兹曼常数1})。例如,通过 Borel 泛函微积分的性质,我们可以看到,对于任何幺正算符,<br />
<br />
<br />
<br />
A different entanglement classification is based on what the quantum correlations present in a state allow A and B to do: one distinguishes three subsets of entangled states: (1) the ''[[Quantum nonlocality|non-local]] states'', which produce correlations that cannot be explained by a local hidden variable model and thus violate a Bell inequality, (2) the ''[[Quantum steering|steerable]] states'' that contain sufficient correlations for A to modify ("steer") by local measurements the conditional reduced state of B in such a way, that A can prove to B that the state they possess is indeed entangled, and finally (3) those entangled states that are neither non-local nor steerable. All three sets are non-empty.<ref name="WJD2007">{{cite journal |title=Steering, Entanglement, Nonlocality, and the Einstein-Podolsky-Rosen Paradox |authors=H. M. Wiseman, S. J. Jones, and A. C. Doherty |journal=Phys. Rev. Lett. |volume=98 |issue=14 |page=140402 |year=2007 |doi=10.1103/PhysRevLett.98.140402 |pmid=17501251 |arxiv=quant-ph/0612147|bibcode=2007PhRvL..98n0402W |s2cid=30078867 }}</ref><br />
<br />
<math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
s (rho) = s left (u rho u ^ * right) . </math > <br />
<br />
<br />
<br />
=== Entropy ===<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
<br />
事实上,如果没有这个属性,冯纽曼熵就不会有明确的定义。<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
<br />
<br />
<br />
In particular, could be the time evolution operator of the system, i.e.,<br />
<br />
特别是,可以是系统的时间演化算子,即,<br />
<br />
==== Definition ====<br />
<br />
[[File:Von Neumann entropy for bipartite system plot.svg|right|thumb|200px|The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.]]<br />
<br />
<math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
<br />
[ math ] u (t) = exp left (frac {-i h t }{ hbar } right) ,[ math ]<br />
<br />
In classical [[information theory]] {{mvar|H}}, the [[Shannon entropy]], is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<ref name="SE">{{cite web |url=http://authors.library.caltech.edu/5516/1/CERpra97b.pdf#page=10 |title=Information-theoretic interpretation of quantum error-correcting codes |first1=Nicolas J. |last1=Cerf |first2=Richard |last2=Cleve }}</ref><br />
<br />
<br />
<br />
where is the Hamiltonian of the system. Here the entropy is unchanged.<br />
<br />
这个系统的哈密顿量在哪里。这里熵不变。<br />
<br />
: <math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
<br />
<br />
<br />
The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the arrow of time towards thermodynamic equilibrium is simply the growing spread of quantum entanglement.<br />
<br />
一个过程的可逆性与由此产生的熵变有关,也就是说,一个过程是可逆的,当且仅当它使系统的熵不变。因此,时间之箭向热力学平衡的前进只不过是量子纠缠的蔓延。<br />
<br />
Since a mixed state {{mvar|ρ}} is a probability distribution over an ensemble, this leads naturally to the definition of the [[von Neumann entropy]]:<br />
<br />
This provides a connection between quantum information theory and thermodynamics.<br />
<br />
这提供了量子信息理论和热力学之间的联系。<br />
<br />
<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
<br />
Rényi entropy also can be used as a measure of entanglement.<br />
<br />
熵也可以用来度量纠缠。<br />
<br />
<br />
<br />
In general, one uses the [[Borel functional calculus]] to calculate a non-polynomial function such as {{math|log<sub>2</sub>(''ρ'')}}. If the nonnegative operator {{mvar|ρ}} acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, {{math|log<sub>2</sub>(''ρ'')}} turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
<br />
<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, entanglement entropy is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<br />
<br />
量子纠缠度量了量子态(通常被视为双体)中纠缠的数量。如前所述,纠缠熵是纯态的标准量度(但不再是混合态的量度)。对于混合态,文献中有一些纠缠度量<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
<br />
<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
<br />
The Reeh-Schlieder theorem of quantum field theory is sometimes seen as an analogue of quantum entanglement.<br />
<br />
量子场论的 Reeh-Schlieder 定理有时被看作是量子纠缠的类比。<br />
<br />
<br />
<br />
:<math> \lim_{p \to 0} p \log p = 0,</math><br />
<br />
<br />
<br />
the convention {{math|0 log(0) {{=}} 0}} is adopted. This extends to the infinite-dimensional case as well: if {{mvar|ρ}} has [[projection-valued measure|spectral resolution]]<br />
<br />
Entanglement has many applications in quantum information theory. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
<br />
纠缠态在量子信息理论中有许多应用。在纠缠的帮助下,否则不可能完成的任务就可能实现。<br />
<br />
<br />
<br />
: <math> \rho = \int \lambda d P_{\lambda},</math><br />
<br />
Among the best-known applications of entanglement are superdense coding and quantum teleportation.<br />
<br />
其中最著名的应用是超稠密编码和量子遥传纠缠。<br />
<br />
<br />
<br />
assume the same convention when calculating<br />
<br />
Most researchers believe that entanglement is necessary to realize quantum computing (although this is disputed by some).<br />
<br />
大多数研究人员认为量子纠缠对于实现量子计算是必要的(尽管有些人对此有争议)。<br />
<br />
<br />
<br />
: <math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
<br />
Entanglement is used in some protocols of quantum cryptography. This is because the "shared noise" of entanglement makes for an excellent one-time pad. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.<br />
<br />
纠缠被用于量子密码学的一些协议中。这是因为纠缠的“共享噪音”造就了绝佳的一次性衬垫。此外,由于测量纠缠对的任何一个成员都会破坏它们共享的纠缠,基于纠缠的量子密码学可以让发送方和接收方更容易地检测到拦截器的存在。<br />
<br />
<br />
<br />
As in [[entropy|statistical mechanics]], the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is {{math|log(2)}} (which can be shown to be the maximum entropy for {{math|2 × 2}} mixed states).<br />
<br />
In interferometry, entanglement is necessary for surpassing the standard quantum limit and achieving the Heisenberg limit.<br />
<br />
在干涉术中,纠缠态对于超越标准量子极限和达到海森堡极限是必要的。<br />
<br />
<br />
<br />
==== As a measure of entanglement ====<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist.<ref name="arxiv.org">{{cite journal|author1=Plenio|title=An introduction to entanglement measures|year=2007|pages=1–51|volume=1|journal=Quant. Inf. Comp. |arxiv=quant-ph/0504163|bibcode=2005quant.ph..4163P|last2=Virmani}}</ref> If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
<br />
在理论和实验中经常会出现几种典型的纠缠态。<br />
<br />
<br />
<br />
For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
<br />
For two qubits, the Bell states are<br />
<br />
对于两个量子比特,贝尔态是<br />
<br />
<br />
<br />
It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/''n'',...,1/''n''}. Therefore, a bipartite pure state {{math|''ρ'' ∈ ''H''<sub>A</sub> ⊗ ''H''<sub>B</sub>}} is said to be a '''maximally entangled state''' if the reduced state{{clarify|reason=To which system, A or B, or perhaps both?|date=May 2015}} of {{mvar|ρ}} is the diagonal matrix<br />
<br />
<math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
<br />
< math > | Phi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 0 rangle _ b | 1 rangle _ a o times | 1 rangle _ b) </math > <br />
<br />
<br />
<br />
<math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
<br />
< math > | Psi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 1 rangle _ b pm | 1 rangle _ a o times | 0 rangle _ b) </math > .<br />
<br />
: <math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
<br />
<br />
<br />
These four pure states are all maximally entangled (according to the entropy of entanglement) and form an orthonormal basis (linear algebra) of the Hilbert space of the two qubits. They play a fundamental role in Bell's theorem.<br />
<br />
这四个纯态都是最大纠缠态(根据纠缠熵) ,并且形成了两个量子位的希尔伯特空间的标准正交基(线性代数)。它们在贝尔定理中起着基本的作用。<br />
<br />
For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
<br />
<br />
<br />
For M>2 qubits, the GHZ state is<br />
<br />
对于 m > 2量子位,GHZ 态是<br />
<br />
As an aside, the information-theoretic definition is closely related to [[entropy (statistical views)|entropy]] in the sense of statistical mechanics{{Citation needed|date=January 2009}} (comparing the two definitions in the present context, it is customary to set the [[Boltzmann constant]] {{math|''k'' {{=}} 1}}). For example, by properties of the [[Borel functional calculus]], we see that for any [[unitary operator]] {{mvar|U}},<br />
<br />
<br />
<br />
<math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
<br />
< math > | mathrm { GHZ } rangle = frac { | 0 rangle ^ { otimes m } + | 1 rangle ^ { otimes m }{ sqrt {2} ,</math > <br />
<br />
: <math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
<br />
<br />
which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to qudits, i.e., systems of d rather than 2 dimensions.<br />
<br />
它缩小到贝尔状态。传统的 GHZ 状态定义为 < math > m = 3 </math > 。GHZ 状态偶尔会扩展到 qudit,即 d 而不是2维系统。<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
<br />
<br />
<br />
Also for M>2 qubits, there are spin squeezed states. Spin squeezed states are a class of squeezed coherent states satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled. Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<br />
<br />
对于 m > 2量子位,也存在自旋压缩态。自旋压缩态是一类对自旋测量不确定度满足一定限制的压缩相干态,它必然是纠缠态。自旋压缩态是利用量子纠缠增强精密测量的理想候选态。<br />
<br />
In particular, {{mvar|U}} could be the time evolution operator of the system, i.e.,<br />
<br />
<br />
<br />
For two bosonic modes, a NOON state is<br />
<br />
对于两个玻色模态,NOON 状态是<br />
<br />
: <math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
<br />
<br />
<br />
<math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
<br />
[数学] | psi _ text { NOON } rangle = frac { | n rangle _ a | 0 rangle _ b + | {0} rangle _ a | { n } rangle _ b }{ sqrt {2} ,,</math > <br />
<br />
where {{mvar|H}} is the [[Hamiltonian (quantum mechanics)|Hamiltonian]] of the system. Here the entropy is unchanged.<br />
<br />
<br />
<br />
This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the N photons are in one mode" and "the N photons are in the other mode".<br />
<br />
这就像贝尔态 < math > | Psi ^ + rangle </math > 除了基函数0和1已经被“ n 个光子处于一种模式”和“ n 个光子处于另一种模式”所取代。<br />
<br />
The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the [[arrow of time]] towards [[thermodynamic equilibrium]] is simply the growing spread of quantum entanglement.<ref>{{cite news |url=https://www.wired.com/2014/04/quantum-theory-flow-time/ |title=New Quantum Theory Could Explain the Flow of Time |last1=Wolchover |first1=Natalie |date=25 April 2014 |website=www.wired.com |publisher=Quanta Magazine |accessdate=27 April 2014}}</ref><br />
<br />
This provides a connection between [[quantum information theory]] and [[thermodynamics]].<br />
<br />
Finally, there also exist twin Fock states for bosonic modes, which can be created by feeding a Fock state into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<br />
<br />
最后,还存在玻色子模式的双 Fock 态,它可以通过将 Fock 态输入到两个导致分束器的臂来产生。它们是 NOON 态的倍数之和,可以用来实现海森堡极限。<br />
<br />
<br />
<br />
[[Rényi entropy]] also can be used as a measure of entanglement.<br />
<br />
For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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对于适当选择的纠缠度量,Bell、 GHZ 和 NOON 态是最大纠缠态,而自旋压缩态和双 Fock 态只是部分纠缠。部分纠缠态通常更容易在实验上准备。<br />
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<br />
<br />
=== Entanglement measures ===<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, [[entropy of entanglement|entanglement entropy]] is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<ref name="arxiv.org" /> and no single one is standard.<br />
<br />
Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is spontaneous parametric down-conversion to generate a pair of photons entangled in polarisation. Other methods include the use of a fiber coupler to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a quantum dot, the use of the Hong–Ou–Mandel effect, etc., In the earliest tests of Bell's theorem, the entangled particles were generated using atomic cascades.<br />
<br />
纠缠通常是由亚原子粒子间的直接相互作用产生的。这些相互作用可以有多种形式。最常用的方法之一是用自发参量下转换产生一对纠缠在偏振中的光子。其他方法包括使用光纤耦合器来限制和混合光子,量子点中双激子衰变级联发射的光子,Hong-Ou-Mandel 效应的使用等等。在贝尔定理最早的测试中,纠缠粒子是利用原子级联产生的。<br />
<br />
* Entanglement cost<br />
<br />
* [[entanglement distillation|Distillable entanglement]]<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of entanglement swapping. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<br />
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通过使用纠缠交换,也有可能在不直接相互作用的量子系统之间创造纠缠。如果它们的波函数在空间上仅仅重叠,至少是部分重叠,那么它们也可以相互纠缠全同粒子。<br />
<br />
* Entanglement of formation<br />
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* [[quantum relative entropy|Relative entropy of entanglement]]<br />
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* [[Squashed entanglement]]<br />
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* [[Logarithmic negativity]]<br />
<br />
A density matrix ρ is called separable if it can be written as a convex sum of product states, namely<br />
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密度矩阵 ρ 称为可分的,如果它可以写成乘积态的凸和,即<br />
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Most (but not all) of these entanglement measures reduce for pure states to entanglement entropy, and are difficult ([[NP-hard]]) to compute.<ref>{{cite journal|last1=Huang|first1=Yichen|title=Computing quantum discord is NP-complete|journal=New Journal of Physics|date=21 March 2014|volume=16|issue=3|pages=033027|doi=10.1088/1367-2630/16/3/033027|bibcode=2014NJPh...16c3027H|arxiv = 1305.5941 |s2cid=118556793}}</ref><br />
<br />
<br />
<br />
<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
<br />
显示方式{ rho = sum _ j p _ j rho _ j ^ {(a)}次 rho _ j ^ {(b)}} </math > <br />
<br />
=== Quantum field theory ===<br />
<br />
The [[Reeh-Schlieder theorem]] of [[quantum field theory]] is sometimes seen as an analogue of quantum entanglement.<br />
<br />
with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
<br />
概率为1 ge p _ j ge 0 </math > 。根据定义,如果一个态不可分离,它就是纠缠态。<br />
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<br />
<br />
== Applications ==<br />
<br />
For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple Peres–Horodecki criterion provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes NP-hard when generalized. Other separability criteria include (but not limited to) the range criterion, reduction criterion, and those based on uncertainty relations. See Ref. for a review of separability criteria in discrete variable systems.<br />
<br />
对于2量子比特和2 × 2量子比特-量子特里特系统(分别为2 × 2和2 × 3) ,简单的 Peres-horowitz 准则为分离提供了一个必要和充分的判据,从而无意识地提供了检测纠缠的判据。然而,对于一般情形,该判据仅仅是可分性的必要条件,因为问题一经推广就变成了 np 难问题。其他可分性标准包括(但不限于)范围标准、归约标准和基于不确定关系的标准。参见参考文献。回顾了离散变量系统的可分性准则。<br />
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<br />
Entanglement has many applications in [[quantum information theory]]. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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A numerical approach to the problem is suggested by Jon Magne Leinaas, Jan Myrheim and Eirik Ovrum in their paper "Geometrical aspects of entanglement". Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in Peres-Horodecki criterion testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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Jon Magne Leinaas,Jan Myrheim 和 Eirik Ovrum 在他们的论文“纠缠的几何方面”中提出了一个数值方法来解决这个问题。莱纳斯等。提供一个数值方法,迭代精炼一个估计的可分离状态朝向要测试的目标状态,并检查目标状态是否确实能够到达。该算法的一个实现(包括内置的 peres-horowitz 标准测试)是[ StateSeparator http://phweb.technion.ac.il/~StateSeparator/] web-app。<br />
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<br />
Among the best-known applications of entanglement are [[superdense coding]] and [[quantum teleportation]].<ref>{{cite journal |last1=Bouwmeester |first1=Dik |last2=Pan |first2=Jian-Wei|last3=Mattle |first3=Klaus|last4=Eibl |first4=Manfred |last5=Weinfurter |first5=Harald|last6=Zeilinger |first6=Anton|year=1997 |title=Experimental Quantum Teleportation |journal=Nature |volume=390 |issue=6660 |pages=575–579 |name-list-style=amp |url=http://qudev.ethz.ch/content/courses/QSIT06/pdfs/Bouwmeester97.pdf |doi=10.1038/37539|bibcode = 1997Natur.390..575B |arxiv=1901.11004 |s2cid=4422887 }}</ref><br />
<br />
In continuous variable systems, the Peres-Horodecki criterion also applies. Specifically, Simon formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref. for a seemingly different but essentially equivalent approach). It was later found that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators or by using entropic measures.<br />
<br />
在连续变量系统中,Peres-Horodecki 准则也适用。具体地说,Simon 根据正则算符的二阶矩,制定了 Peres-Horodecki 准则的一个特定版本,并表明它对于 < math > 1 oplus1 </math >-mode Gaussian 状态是必要的和充分的。看似不同,但本质上等价的方法)。后来发现,Simon 的条件对于 < math > 1 oplus n </math >-mode Gaussian 状态也是必要和充分的,但是对于 < math > 2 oplus2 </math >-mode Gaussian 状态不再是充分的。Simon 条件可以通过考虑正则算子的高阶矩或者用熵测度来推广。<br />
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<br />
Most researchers believe that entanglement is necessary to realize [[quantum computer|quantum computing]] (although this is disputed by some).<ref name="jozsa02">{{cite journal|author1=Richard Jozsa|author2=Noah Linden|doi=10.1098/rspa.2002.1097|title=On the role of entanglement in quantum computational speed-up|year=2002|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=459|issue=2036|pages=2011–2032|arxiv=quant-ph/0201143|bibcode = 2003RSPSA.459.2011J |citeseerx=10.1.1.251.7637|s2cid=15470259}}</ref><br />
<br />
In 2016 China launched the world’s first quantum communications satellite. The $100m Quantum Experiments at Space Scale (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
<br />
2016年,中国发射了世界上第一颗量子通信卫星。耗资1亿美元的空间量子实验任务于2016年8月16日当地时间01:40从中国北方的酒泉卫星发射中心空间站发射升空。<br />
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<br />
Entanglement is used in some protocols of [[quantum cryptography]].<ref name="ekert91">{{cite journal |doi=10.1103/PhysRevLett.67.661 |title=Quantum cryptography based on Bell's theorem |year=1991 |last1=Ekert |first1=Artur K. |journal=Physical Review Letters |volume=67 |issue=6 |pages=661–663 |pmid=10044956|bibcode = 1991PhRvL..67..661E |s2cid=27683254 |url=http://pdfs.semanticscholar.org/f8dc/c3047eef8da135bca13b926b1e6cf50e7f3a.pdf }}</ref><ref name="horodecki10">{{cite arXiv |eprint=1006.0468|last1=Yin|first1=Juan|title=Contextuality offers device-independent security|last2=Cao|first2=Yuan|last3=Yong|first3=Hai-Lin|last4=Ren|first4=Ji-Gang|last5=Liang|first5=Hao|last6=Liao|first6=Sheng-Kai|last7=Zhou|first7=Fei|last8=Liu|first8=Chang|last9=Wu|first9=Yu-Ping|last10=Pan|first10=Ge-Sheng|last11=Zhang|first11=Qiang|last12=Peng|first12=Cheng-Zhi|last13=Pan|first13=Jian-Wei|class=quant-ph|year=2010}}</ref> This is because the "shared noise" of entanglement makes for an excellent [[one-time pad]]. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.{{citation needed|date=January 2018}}<br />
<br />
For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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在接下来的两年里,这艘以中国古代哲学家墨子命名的飞船将展示量子化的可行性<br />
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<br />
<br />
communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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地球和太空之间的通信,并在前所未有的距离上测试量子纠缠。<br />
<br />
In [[interferometry]], entanglement is necessary for surpassing the [[standard quantum limit]] and achieving the [[Heisenberg limit]].<ref>{{cite journal |last1=Pezze |first1=Luca |last2=Smerzi |first2=Augusto|year=2009 |title=Entanglement, Nonlinear Dynamics, and the Heisenberg Limit |journal=Phys. Rev. Lett. |volume=102 |issue=10 |pages=100401 |name-list-style=amp |doi=10.1103/PhysRevLett.102.100401 |pmid=19392092 |bibcode=2009PhRvL.102j0401P|arxiv = 0711.4840 |s2cid=13095638 }}</ref><br />
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<br />
<br />
In the June 16, 2017, issue of Science, Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<br />
<br />
在2017年6月16日的《科学》杂志上。在严格的爱因斯坦定域条件下,从墨丘利卫星到 Lijian、云南和 Delingha、 Quinhai 的基地的 CHSH 估值为2.37 ± 0.09,证明了双光子对的存在和对 Bell 不等式的违反,从而提高了数量级通过光纤实验的传输效率。<br />
<br />
=== Entangled states ===<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
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For two [[qubits]], the [[Bell state]]s are<br />
<br />
The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be calculated only by consideration of electron entanglement.<br />
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多电子原子的电子壳层总是由纠缠电子组成。只有考虑到电子纠缠,才能计算出正确的电离能。<br />
<br />
<br />
<br />
: <math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
<br />
: <math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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<br />
<br />
It has been suggested that in the process of photosynthesis, entanglement is involved in the transfer of energy between light-harvesting complexes and photosynthetic reaction centers where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using femtosecond spectroscopy, the coherence of entanglement in the Fenna-Matthews-Olson complex was measured over hundreds of femtoseconds (a relatively long time in this regard) providing support to this theory.<br />
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研究表明,在光合作用过程中,纠缠参与了捕光复合物与光合反应中心之间的能量传递,而光(能)是以化学能的形式获得的。没有这样一个过程,光转化为化学能的有效性就无从解释。利用飞秒光谱技术,我们测量了 Fenna-Matthews-Olson 复合体中纠缠态的相干性,时间长达数百飞秒,为这一理论提供了支持。<br />
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These four pure states are all maximally entangled (according to the [[entropy of entanglement]]) and form an [[orthonormal]] [[basis (linear algebra)]] of the Hilbert space of the two qubits. They play a fundamental role in [[Bell's theorem]].<br />
<br />
However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<br />
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然而,关键的后续研究对这些结果的解释提出了质疑,并将报告的电子量子相干特征赋予了发色团中的核动力学。<br />
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<br />
For M>2 qubits, the [[Greenberger–Horne–Zeilinger state|GHZ state]] is<br />
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In 2020 researchers reported the quantum entanglement between the motion of a millimetre-sized mechanical oscillator and a disparate distant spin system of a cloud of atoms.<br />
<br />
2020年,研究人员报告了一个毫米大小的机械振荡器的运动和一个原子云的不同距离的自旋系统之间的量子纠缠。<br />
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: <math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
<br />
<br />
<br />
which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to [[qudit]]s, i.e., systems of ''d'' rather than 2 dimensions.<br />
<br />
In October 2018, physicists reported producing quantum entanglement using living organisms, particularly between photosynthetic molecules within living bacteria and quantized light.<br />
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2018年10月,物理学家报告说,他们利用活体生物制造量子纠缠,特别是利用活体细菌中的光合分子和量子化的光。<br />
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Also for M>2 qubits, there are [[Spin squeezing|spin squeezed states]].<ref>[http://qwiki.stanford.edu/index.php/Spin_Squeezed_State Database error – Qwiki] {{webarchive|url=https://web.archive.org/web/20120821011018/http://qwiki.stanford.edu/index.php/Spin_Squeezed_State |date=21 August 2012 }}</ref> Spin squeezed states are a class of [[squeezed coherent states]] satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled.<ref>{{cite journal | last1 = Kitagawa | first1 = Masahiro | last2 = Ueda | first2 = Masahito | year = 1993 | title = Squeezed Spin States | journal = Phys. Rev. A | volume = 47 | issue = 6| pages = 5138–5143 | doi=10.1103/physreva.47.5138| pmid = 9909547 |bibcode = 1993PhRvA..47.5138K }}</ref> Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<ref>{{cite journal | last1 = Wineland | first1 = D. J. | last2 = Bollinger | first2 = J. J. | last3 = Itano | first3 = W. M. | last4 = Moore | first4 = F. L. | last5 = Heinzen | first5 = D. J. | year = 1992| title = Spin squeezing and reduced quantum noise in spectroscopy | url = | journal = Phys. Rev. A | volume = 46| issue = 11| pages = R6797–R6800| doi = 10.1103/PhysRevA.46.R6797 | pmid = 9908086 |bibcode = 1992PhRvA..46.6797W }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<br />
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生物体(绿色硫细菌)已被研究作为介质,在非相互作用的光模式之间创造量子纠缠,表明光和细菌模式之间的高度纠缠,甚至在某种程度上纠缠在细菌内部。<br />
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<br />
For two [[boson]]ic modes, a [[NOON state]] is<br />
<br />
<br />
<br />
: <math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
<br />
<br />
<br />
This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the ''N'' photons are in one mode" and "the ''N'' photons are in the other mode".<br />
<br />
<br />
<br />
Finally, there also exist [[twin Fock states]] for bosonic modes, which can be created by feeding a [[Fock state]] into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.71.1355|pmid = 10055519|title = Interferometric detection of optical phase shifts at the Heisenberg limit|journal = Physical Review Letters|volume = 71|issue = 9|pages = 1355–1358|year = 1993|last1 = Holland|first1 = M. J|last2 = Burnett|first2 = K|bibcode = 1993PhRvL..71.1355H}}</ref><br />
<br />
<br />
<br />
For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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<br />
<br />
=== Methods of creating entanglement ===<br />
<br />
Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is [[spontaneous parametric down-conversion]] to generate a pair of photons entangled in polarisation.<ref name="horodecki2007">{{cite journal |author=Horodecki R, Horodecki P, Horodecki M, Horodecki K |title=Quantum entanglement |journal=Rev. Mod. Phys. |arxiv=quant-ph/0702225 |doi =10.1103/RevModPhys.81.865 |year=2009|pages=865–942 |bibcode=2009RvMP...81..865H |volume=81 |issue=2|last2=Horodecki |last3=Horodecki |last4=Horodecki |s2cid=59577352 }}</ref> Other methods include the use of a [[fiber coupler]] to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a [[quantum dot]],<ref>{{Cite journal|last=Akopian|first=N.|date=2006|title=Entangled Photon Pairs from Semiconductor Quantum Dots|journal=Phys. Rev. Lett.|volume=96|issue=2|pages=130501|arxiv=quant-ph/0509060|bibcode=2006PhRvL..96b0501D|doi=10.1103/PhysRevLett.96.020501|pmid=16486553|s2cid=22040546}}</ref> the use of the [[Hong–Ou–Mandel effect]], etc., In the earliest tests of Bell's theorem, the entangled particles were generated using [[atomic cascade]]s.<br />
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<br />
<br />
It is also possible to create entanglement between quantum systems that never directly interacted, through the use of [[Quantum teleportation#Entanglement swapping|entanglement swapping]]. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<ref>Rosario Lo Franco and Giuseppe Compagno, "Indistinguishability of Elementary Systems as a Resource for Quantum Information Processing", Phys. Rev. Lett. 120, 240403, 14 June 2018.</ref><br />
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<br />
<br />
=== Testing a system for entanglement ===<br />
<br />
<br />
<br />
A density matrix ρ is called [[Separable state|separable]] if it can be written as a convex sum of product states, namely<br />
<br />
<br />
<br />
<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
<br />
<br />
<br />
with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple [[Peres–Horodecki criterion]] provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes [[NP-hard]] when generalized.<ref name="NP-hard1">Gurvits, L., Classical deterministic complexity of Edmonds' problem and quantum entanglement, in Proceedings of the 35th ACM Symposium on Theory of Computing, ACM Press, New York, 2003.</ref><ref name="NP-hard2">Sevag Gharibian, Strong NP-Hardness of the [[Quantum Separability Problem]], [[Quantum Information]] and what's known as [[Quantum Computing]], Vol. 10, No. 3&4, pp. 343–360, 2010. {{arXiv|0810.4507}}.</ref> Other separability criteria include (but not limited to) the [[range criterion]], [[reduction criterion]], and those based on uncertainty relations.<ref>{{cite journal |last1=Hofmann |first1=Holger F. |last2=Takeuchi |first2=Shigeki |title=Violation of local uncertainty relations as a signature of entanglement |journal=Physical Review A |date=22 September 2003 |volume=68 |issue=3 |page=032103 |doi=10.1103/PhysRevA.68.032103|arxiv=quant-ph/0212090 |bibcode=2003PhRvA..68c2103H |s2cid=54893300 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |title=Characterizing Entanglement via Uncertainty Relations |journal=Physical Review Letters |date=18 March 2004 |volume=92 |issue=11 |page=117903 |doi=10.1103/PhysRevLett.92.117903|pmid=15089173 |arxiv=quant-ph/0306194 |bibcode=2004PhRvL..92k7903G |s2cid=5696147 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |last2=Lewenstein |first2=Maciej |title=Entropic uncertainty relations and entanglement |journal=Physical Review A |date=24 August 2004 |volume=70 |issue=2 |page=022316 |doi=10.1103/PhysRevA.70.022316|bibcode=2004PhRvA..70b2316G |arxiv=quant-ph/0403219 |s2cid=118952931 }}</ref><ref>{{cite journal |last1=Huang |first1=Yichen |title=Entanglement criteria via concave-function uncertainty relations |journal=Physical Review A |date=29 July 2010 |volume=82 |issue=1 |page=012335 |doi=10.1103/PhysRevA.82.012335|bibcode=2010PhRvA..82a2335H }}</ref> See Ref.<ref>{{cite journal|last1=Gühne|first1=Otfried|last2=Tóth|first2=Géza|title=Entanglement detection|journal=Physics Reports|volume=474|issue=1–6|pages=1–75|doi=10.1016/j.physrep.2009.02.004|arxiv = 0811.2803 |bibcode = 2009PhR...474....1G |year=2009|s2cid=119288569}}</ref> for a review of separability criteria in discrete variable systems.<br />
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A numerical approach to the problem is suggested by [[Jon Magne Leinaas]], [[Jan Myrheim]] and [[Eirik Ovrum]] in their paper "Geometrical aspects of entanglement".<ref name="geom approach">{{cite journal | last1 = Leinaas| first1 = Jon Magne| last2 = Myrheim| first2 = Jan| last3 = Ovrum| first3 = Eirik| year = 2006 | title = Geometrical aspects of entanglement | url = | journal = Physical Review A | volume = 74 | issue = | page = 012313 | doi = 10.1103/PhysRevA.74.012313| arxiv = quant-ph/0605079| s2cid = 119443360}}</ref> Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in [[Peres-Horodecki criterion]] testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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In continuous variable systems, the [[Peres-Horodecki criterion]] also applies. Specifically, Simon <ref>{{cite journal|last1=Simon|first1=R.|title=Peres-Horodecki Separability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2726–2729|doi=10.1103/PhysRevLett.84.2726|arxiv = quant-ph/9909044 |bibcode = 2000PhRvL..84.2726S|pmid=11017310|year=2000|s2cid=11664720}}</ref> formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref.<ref>{{cite journal|last1=Duan|first1=Lu-Ming|last2=Giedke|first2=G.|last3=Cirac|first3=J. I.|last4=Zoller|first4=P.|title=Inseparability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2722–2725|doi=10.1103/PhysRevLett.84.2722|pmid=11017309|arxiv = quant-ph/9908056 |bibcode = 2000PhRvL..84.2722D |year=2000|s2cid=9948874}}</ref> for a seemingly different but essentially equivalent approach). It was later found <ref>{{cite journal|last1=Werner|first1=R. F.|last2=Wolf|first2=M. M.|title=Bound Entangled Gaussian States|journal=Physical Review Letters|volume=86|issue=16|pages=3658–3661|doi=10.1103/PhysRevLett.86.3658|pmid=11328047|arxiv = quant-ph/0009118 |bibcode = 2001PhRvL..86.3658W |year=2001|s2cid=20897950}}</ref> that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators <ref>{{cite journal|last1=Shchukin|first1=E.|last2=Vogel|first2=W.|title=Inseparability Criteria for Continuous Bipartite Quantum States|journal=Physical Review Letters|volume=95|issue=23|pages=230502|doi=10.1103/PhysRevLett.95.230502|pmid=16384285|arxiv = quant-ph/0508132 |bibcode = 2005PhRvL..95w0502S |year=2005|s2cid=28595936}}</ref><ref>{{cite journal|last1=Hillery|first1=Mark|last2=Zubairy|first2=M.Suhail|title=Entanglement Conditions for Two-Mode States|journal=Physical Review Letters|volume=96|issue=5|doi=10.1103/PhysRevLett.96.050503|arxiv = quant-ph/0507168 |bibcode = 2006PhRvL..96e0503H|pmid=16486912|page=050503|year=2006|s2cid=43756465}}</ref> or by using entropic measures.<ref>{{cite journal|last1=Walborn|first1=S.|last2=Taketani|first2=B.|last3=Salles|first3=A.|last4=Toscano|first4=F.|last5=de Matos Filho|first5=R.|title=Entropic Entanglement Criteria for Continuous Variables|journal=Physical Review Letters|volume=103|issue=16|doi=10.1103/PhysRevLett.103.160505|arxiv = 0909.0147 |bibcode = 2009PhRvL.103p0505W|pmid=19905682|page=160505|year=2009|s2cid=10523704}}</ref><ref>{{cite journal |last1=Yichen Huang |title=Entanglement Detection: Complexity and Shannon Entropic Criteria |journal=IEEE Transactions on Information Theory |date=October 2013 |volume=59 |issue=10 |pages=6774–6778 |doi=10.1109/TIT.2013.2257936|s2cid=7149863 }}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite.<ref>http://physicsworld.com/cws/article/news/2016/aug/16/china-launches-world-s-first-quantum-science-satellite</ref> The $100m [[Quantum Experiments at Space Scale]] (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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In the June 16, 2017, issue of ''Science'', Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<ref>{{cite journal | doi = 10.1126/science.aan3211 | volume=356 | title=Satellite-based entanglement distribution over 1200 kilometers | year=2017 | journal=Science | pages=1140–1144 | last1 = Yin | first1 = Juan | last2 = Cao | first2 = Yuan | last3 = Li | first3 = Yu-Huai | last4 = Liao | first4 = Sheng-Kai | last5 = Zhang | first5 = Liang | last6 = Ren | first6 = Ji-Gang | last7 = Cai | first7 = Wen-Qi | last8 = Liu | first8 = Wei-Yue | last9 = Li | first9 = Bo | last10 = Dai | first10 = Hui | last11 = Li | first11 = Guang-Bing | last12 = Lu | first12 = Qi-Ming | last13 = Gong | first13 = Yun-Hong | last14 = Xu | first14 = Yu | last15 = Li | first15 = Shuang-Lin | last16 = Li | first16 = Feng-Zhi | last17 = Yin | first17 = Ya-Yun | last18 = Jiang | first18 = Zi-Qing | last19 = Li | first19 = Ming | last20 = Jia | first20 = Jian-Jun | last21 = Ren | first21 = Ge | last22 = He | first22 = Dong | last23 = Zhou | first23 = Yi-Lin | last24 = Zhang | first24 = Xiao-Xiang | last25 = Wang | first25 = Na | last26 = Chang | first26 = Xiang | last27 = Zhu | first27 = Zhen-Cai | last28 = Liu | first28 = Nai-Le | last29 = Chen | first29 = Yu-Ao | last30 = Lu | first30 = Chao-Yang | last31 = Shu | first31 = Rong | last32 = Peng | first32 = Cheng-Zhi | last33 = Wang | first33 = Jian-Yu | last34 = Pan | first34 = Jian-Wei | issue=6343 | pmid = 28619937| doi-access = free }}</ref><ref>{{cite web | url=http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance | title=China's quantum satellite achieves 'spooky action' at record distance| date=2017-06-14}}</ref><br />
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== Naturally entangled systems ==<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be [[Configuration interaction|calculated]] only by consideration of electron entanglement.<ref>Frank Jensen: ''Introduction to Computational Chemistry.'' Wiley, 2007, {{ISBN|978-0-470-01187-4}}.</ref><br />
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== Photosynthesis ==<br />
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It has been suggested that in the process of [[photosynthesis]], entanglement is involved in the transfer of energy between [[light-harvesting complex]]es and [[photosynthetic reaction center]]s where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using [[femtosecond spectroscopy]], the coherence of entanglement in the [[Fenna-Matthews-Olson complex]] was measured over hundreds of [[femtosecond]]s (a relatively long time in this regard) providing support to this theory.<ref>Berkeley Lab Press Release: ''[http://newscenter.lbl.gov/feature-stories/2010/05/10/untangling-quantum-entanglement/ Untangling the Quantum Entanglement Behind Photosynthesis: Berkeley scientists shine new light on green plant secrets.]''</ref><ref>Mohan Sarovar, Akihito Ishizaki, Graham R. Fleming, K. Birgitta Whaley: ''Quantum entanglement in photosynthetic light harvesting complexes.'' {{arxiv|0905.3787}}</ref><br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<ref>{{cite journal | author = R. Tempelaar | author2 = T. L. C. Jansen | author3 = J. Knoester | title = Vibrational Beatings Conceal Evidence of Electronic Coherence in the FMO Light-Harvesting Complex | journal = J. Phys. Chem. B | volume = 118 | issue = 45 | pages = 12865–12872 | date = 2014 | doi=10.1021/jp510074q| pmid = 25321492 }}</ref><ref>{{cite journal | author = N. Christenson | author2 = H. F. Kauffmann | author3 = T. Pullerits | author4 = T. Mancal | title = Origin of Long-Lived Coherences in Light-Harvesting Complexes| journal = J. Phys. Chem. B | volume = 116 | issue = 25 | pages = 7449–7454 | date = 2012 | doi = 10.1021/jp304649c | pmid = 22642682 | pmc = 3789255 | bibcode = 2012arXiv1201.6325C | arxiv = 1201.6325 }}</ref><ref>{{cite journal | author = A. Kolli | author2 = E. J. O’Reilly | author3= G. D. Scholes | author4= A. Olaya-Castro | title = The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae| journal = J. Chem. Phys. | volume = 137 | issue = 17 | pages = 174109 | date = 2012 | doi=10.1063/1.4764100| pmid = 23145719 | bibcode = 2012JChPh.137q4109K | arxiv = 1203.5056 | s2cid = 20156821 }}</ref><ref>{{cite journal | author = V. Butkus | author2 = D. Zigmantas | author3= L. Valkunas | author4= D. Abramavicius | title = Vibrational vs. electronic coherences in 2D spectrum of molecular systems| journal = Chem. Phys. Lett. | volume = 545 | issue = 30 | pages = 40–43 | date = 2012 | doi=10.1016/j.cplett.2012.07.014| arxiv = 1201.2753 | bibcode = 2012CPL...545...40B | s2cid = 96663719 }}</ref><ref>{{cite journal | author = V. Tiwari | author2 = W. K. Peters | author3= D. M. Jonas | title = Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework | journal = Proc. Natl. Acad. Sci. USA | volume = 110 | issue = 4 | pages = 1203–1208 | date = 2013 | doi=10.1073/pnas.1211157110| pmid = 23267114 | pmc = 3557059 }}</ref><ref>{{cite journal | author = E. Thyrhaug | author2 = K. Zidek | author3 = J. Dostal | author4 = D. Bina | author5 = D. Zigmantas | title = Exciton Structure and Energy Transfer in the Fenna−Matthews− Olson Complex| journal = J. Phys. Chem. Lett. | volume = 7 | issue = 9 | pages = 1653–1660 | date = 2016 | doi=10.1021/acs.jpclett.6b00534| pmid = 27082631 }}</ref><ref>{{cite journal | author = Y. Fujihashi | author2 = G. R. Fleming | author3= A. Ishizaki | title = Impact of environmentally induced fluctuations on quantum mechanically mixed electronic and vibrational pigment states in photosynthetic energy transfer and 2D electronic spectra| journal = J. Chem. Phys. | volume = 142 | issue = 21 | pages = 212403 | date = 2015 | doi=10.1063/1.4914302| pmid = 26049423 | arxiv = 1505.05281 | bibcode = 2015JChPh.142u2403F | s2cid = 1082742 }}</ref><br />
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== Entanglement of macroscopic objects ==<br />
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In 2020 researchers reported the quantum entanglement between the [[Vibrations of a circular membrane|motion of a millimetre-sized mechanical oscillator]] and a disparate distant [[Spin (physics)|spin]] system of a cloud of atoms.<ref>{{cite news |title=Quantum entanglement realized between distant large objects |url=https://phys.org/news/2020-09-quantum-entanglement-distant-large.html |accessdate=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Thomas |first1=Rodrigo A. |last2=Parniak |first2=Michał |last3=Østfeldt |first3=Christoffer |last4=Møller |first4=Christoffer B. |last5=Bærentsen |first5=Christian |last6=Tsaturyan |first6=Yeghishe |last7=Schliesser |first7=Albert |last8=Appel |first8=Jürgen |last9=Zeuthen |first9=Emil |last10=Polzik |first10=Eugene S. |title=Entanglement between distant macroscopic mechanical and spin systems |journal=Nature Physics |date=21 September 2020 |pages=1–6 |doi=10.1038/s41567-020-1031-5 |url=https://www.nature.com/articles/s41567-020-1031-5 |accessdate=9 October 2020 |language=en |issn=1745-2481}}</ref><br />
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=== Entanglement of elements of living systems ===<br />
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In October 2018, physicists reported producing quantum entanglement using [[living organism]]s, particularly between photosynthetic molecules within living [[bacteria]] and [[Photon|quantized light]].<ref name="JPC-20181010">{{cite journal |last1=Marletto |first1=C. |last2=Coles |first2=D.M. |last3=Farrow |first3=T. |last4=Vedral |first4=V. |title=Entanglement between living bacteria and quantized light witnessed by Rabi splitting |date=10 October 2018 |journal=Journal of Physics: Communications |volume=2 |pages=101001 |number=10 |doi=10.1088/2399-6528/aae224 |bibcode=2018JPhCo...2j1001M |arxiv=1702.08075 |s2cid=119236759 }} [[File:CC-BY icon.svg|50px]] Text and images are available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref><ref name="SA-20181029">{{cite web |last=O'Callaghan |first=Jonathan |title="Schrödinger's Bacterium" Could Be a Quantum Biology Milestone – A recent experiment may have placed living organisms in a state of quantum entanglement |url=https://www.scientificamerican.com/article/schroedingers-bacterium-could-be-a-quantum-biology-milestone/ |date=29 October 2018 |work=[[Scientific American]] |accessdate=29 October 2018 }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<ref>{{cite journal | last1 = Krisnanda | first1 = T. | last2 = Marletto | first2 = C. | last3 = Vedral | first3 = V. | last4 = Paternostro | first4 = M. | last5 = Paterek | first5 = T. | year = 2018 | title = Probing quantum features of photosynthetic organisms | url = https://www.nature.com/articles/s41534-018-0110-2 | journal = NPJ Quantum Information | volume = 4 | issue = | page = 60 | doi = 10.1038/s41534-018-0110-2 | doi-access = free }}</ref><br />
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== See also ==<br />
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{{Portal|Physics}}<br />
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{{cols|colwidth=21em}}<br />
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* [[Quantum gate#Controlled gates|CNOT gate]]<br />
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* [[Bound entanglement]]<br />
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* [[Concurrence (quantum computing)]]<br />
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* [[Einstein's thought experiments]]<br />
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* [[Entanglement distillation]]<br />
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* [[Entanglement witness]]<br />
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* [[Faster-than-light communication]]<br />
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* [[Ghirardi–Rimini–Weber theory]]<br />
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* [[Multipartite entanglement]]<br />
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* [[Normally distributed and uncorrelated does not imply independent]]<br />
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* [[Observer effect (physics)]]<br />
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* [[Quantum coherence]]<br />
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* [[Quantum discord]]<br />
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* [[Quantum phase transition]]<br />
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* [[Quantum computing]]<br />
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* [[Quantum network]]<br />
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Category:Quantum information science<br />
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类别: 量子信息科学<br />
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* [[Quantum pseudo-telepathy]]<br />
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Category:Quantum mechanics<br />
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类别: 量子力学<br />
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* [[Quantum teleportation]]<br />
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Category:Unsolved problems in physics<br />
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类别: 物理学中未解决的问题<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Quantum entanglement]]. Its edit history can be viewed at [[量子纠缠/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%87%8F%E5%AD%90%E7%BA%A0%E7%BC%A0&diff=21222量子纠缠2021-01-22T13:39:47Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Correlation between measurements of quantum subsystems, even when spatially separated}}<br />
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[[File:SPDC figure.png|right|thumb|275px|[[Spontaneous parametric down-conversion]] process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[[Spontaneous parametric down-conversion process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[自发参量下转换过程可以将光子分裂成具有相互垂直极化的 II 型光子对。]<br />
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{{Quantum mechanics|fundamentals}}<br />
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'''Quantum entanglement''' is a physical phenomenon that occurs when a pair or group of [[particle]]s are generated, interact, or share spatial proximity in a way such that the [[quantum state]] of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the [[principle of locality|disparity between classical and quantum physics]]: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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量子纠缠是一种物理现象,描述的是当一对或一组粒子被产生、相互作用或共享空间邻近性时(包括当粒子被大距离分离时),该对或该组粒子中的每个粒子的量子态都无法独立于其他粒子的态。量子纠缠是经典物理学和量子物理学之间差别悬殊的核心问题:纠缠是量子力学的一个主要特征,而经典力学却没有这种特征。<br />
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[[Measurement#Quantum mechanics|Measurements]] of [[physical properties]] such as [[position (vector)|position]], [[momentum]], [[spin (physics)|spin]], and [[polarization (waves)|polarization]] performed on entangled particles can, in some cases, be found to be perfectly [[correlated]]. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly [[paradox]]ical effects: any measurement of a property of a particle results in an irreversible [[wave function collapse]] of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a property of a particle results in an irreversible wave function collapse of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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在某些情况下,对纠缠粒子的位置、动量、自旋和偏振等物理性质的测量的结果可以是完全相关的。例如,如果一对纠缠粒子的产生使得它们的总自旋已知为零,并且我们发现一个粒子在第一个轴上具有顺时针自旋,那么在同一个轴上测量的另一个粒子的自旋将会是逆时针的。然而,这种行为产生了看似矛盾的效应:对粒子性质的任何测量都会导致该粒子的不可逆波函数崩溃,并将改变原来的量子态。在粒子纠缠的情况下,这样的测量将影响整个纠缠系统。<br />
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Such phenomena were the subject of a 1935 paper by [[Albert Einstein]], [[Boris Podolsky]], and [[Nathan Rosen]],<ref name="Einstein1935"><br />
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Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen, and several papers by Erwin Schrödinger shortly thereafter, describing what came to be known as the EPR paradox. Einstein and others considered such behavior to be impossible, as it violated the local realism view of causality (Einstein referring to it as "spooky action at a distance") and argued that the accepted formulation of quantum mechanics must therefore be incomplete.<br />
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这些现象是阿尔伯特·爱因斯坦、鲍里斯·波多尔斯基和纳森·罗森在1935年发表的一篇论文和埃尔文·薛定谔随后不久发表的几篇论文的主题,这些论文描述了后来的EPR悖论。爱因斯坦和其他人认为这样的行为是不可能的,因为它违反了因果关系的局部实在论观点(爱因斯坦称之为“远处的幽灵行为”),并认为量子力学的公认公式因此一定是不完整的。<br />
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{{cite journal|author=Einstein A, Podolsky B, Rosen N|last2=Podolsky|last3=Rosen|year=1935|title=Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?|journal=Phys. Rev.|volume=47|issue=10|pages=777–780|bibcode=1935PhRv...47..777E|doi=10.1103/PhysRev.47.777|doi-access=free}}<br />
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</ref> and several papers by [[Erwin Schrödinger]] shortly thereafter,<ref name="Schrödinger1935"><br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<br />
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然而,后来,量子力学的反直觉预测在实验上得到了验证。所谓的“无漏洞”钟试验已经进行,在这种试验中,粒子位置被分开,以光速进行的通信将花费更长的时间——在一次实验中比测量间隔长10000倍<br />
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According to some interpretations of quantum mechanics, the effect of one measurement occurs instantly. Other interpretations which don't recognize wavefunction collapse dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces correlation between the measurements and that the mutual information between the entangled particles can be exploited, but that any transmission of information at faster-than-light speeds is impossible.<br />
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根据量子力学的一些解释,一次测量的效果是瞬间发生的。其他不承认波函数崩塌的解释则认为不存在任何“效应”。然而,所有的解释都同意,纠缠产生了测量之间的相关性,纠缠粒子之间的互信息可以被利用,但任何信息的传输速度都不可能超过光速。<br />
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|title=Discussion of probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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Quantum entanglement has been demonstrated experimentally with photons, neutrinos, electrons, molecules as large as buckyballs, and even small diamonds. The utilization of entanglement in communication, computation and quantum radar is a very active area of research and development.<br />
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量子纠缠已经在光子、中微子、电子、巴基球大小的分子,甚至小钻石的实验中得到证实。纠缠在通信、计算和量子雷达中的应用是一个非常活跃的研究和发展领域。<br />
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|volume=31<br />
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|issue=4<br />
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|pages=555–563<br />
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Article headline regarding the [[Einstein–Podolsky–Rosen paradox (EPR paradox) paper, in the May 4, 1935 issue of The New York Times.]]<br />
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文章标题关于[爱因斯坦-波多尔斯基-罗森悖论(EPR paradox)论文,发表于1935年5月4日的《纽约时报》]<br />
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|year=1935<br />
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|doi=10.1017/S0305004100013554<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.<br />
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1935年,阿尔伯特·爱因斯坦与鲍里斯·波多尔斯基和纳森·罗森在一篇联合论文中首次讨论了量子力学关于强关联系统的反直觉预测。 <br />
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|bibcode = 1935PCPS...31..555S }}</ref><ref name="Schrödinger1936"><br />
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{{cite journal |author=Schrödinger E<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated: Einstein later famously derided entanglement as "spukhafte Fernwirkung" or "spooky action at a distance."<br />
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此后不久,薛定谔发表了一篇影响深远的论文,定义并讨论了“纠缠”的概念在论文中,他承认了这个概念的重要性,并指出了爱因斯坦后来众所周知的对纠缠的嘲弄“幽灵般的超距作用”<br />
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|title=Probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously Bohm's interpretation of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when John Stewart Bell proved that one of their key assumptions, the principle of locality, as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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EPR的论文引起了物理学家的极大兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是Bohm对量子力学的解释),但发表的其他工作相对较少。尽管如此,直到1964年,约翰·斯图尔特·贝尔(John Stewart Bell)证明了他们的一个关键假设,即应用于EPR所希望的隐变量解释的局部性原理,在数学上与量子理论的预测不一致,EPR的论点中的弱点至此才被发现。<br />
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|volume=32<br />
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|issue=3<br />
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Specifically, Bell demonstrated an upper limit, seen in Bell's inequality, regarding the strength of correlations that can be produced in any theory obeying local realism, and showed that quantum theory predicts violations of this limit for certain entangled systems. His inequality is experimentally testable, and there have been numerous relevant experiments, starting with the pioneering work of Stuart Freedman and John Clauser in 1972 and Alain Aspect's experiments in 1982. An early experimental breakthrough was due to Carl Kocher, Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles. Alain Aspect notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / superdeterminism loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<br />
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具体来说,贝尔证明了一个上限,可以在贝尔不等式中看到,关于遵循局部实在论的任何理论中可以产生的关联强度,并表明量子理论预测某些纠缠系统会违反这个极限。从1972年斯图亚特·弗里德曼和约翰·克劳瑟的开创性工作和1982年阿兰·阿斯佩的实验开始,他的不等式在实验上是可以检验的,并且存在许多相关的实验。早期的实验突破归功于卡尔·科彻,科彻的仪器配备了更好的偏振器,弗里德曼和克劳瑟使用了这种仪器,他们可以证实余弦平方依赖性,并用它来证明对一组固定角度的贝尔不等式的违反。阿兰·阿斯佩指出的则是“设置独立漏洞”——他称之为“牵强的”,然而,“不可忽视”的“剩余漏洞”——还没有被关闭,并且自由意志/超决定论的漏洞是无法弥补的;他说“没有任何实验,尽可能的理想情况,可以说是完全没有漏洞的。” <br />
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|pages=446–452<br />
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|year=1936<br />
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A minority opinion holds that although quantum mechanics is correct, there is no superluminal instantaneous action-at-a-distance between entangled particles once the particles are separated.<br />
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少数人认为,尽管量子力学是正确的,但是一旦粒子分离,纠缠的粒子之间并不存在超光速瞬时作用。<br />
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|doi=10.1017/S0305004100019137<br />
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|bibcode = 1936PCPS...32..446S }}<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of quantum key distribution protocols, most famously BB84 by Charles H. Bennett and Gilles Brassard and E91 by Artur Ekert. Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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贝尔的工作提出了利用这些超强相关性作为交流资源的可能性。它导致了1984年量子密钥分配协议的发现,其中最著名的是查尔斯·H·班纳特和吉尔斯 布拉萨德的BB84和艾特 艾克特的E91。虽然BB84不使用纠缠,但是艾克特的协议使用了对Bell不等式的违反作为安全性的证明。 <br />
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</ref> describing what came to be known as the [[EPR paradox]]. Einstein and others considered such behavior to be impossible, as it violated the [[local realism]] view of causality (Einstein referring to it as "spooky [[action at a distance]]")<ref>Physicist John Bell depicts the Einstein camp in this debate in his article entitled "Bertlmann's socks and the nature of reality", p. 143 of ''Speakable and unspeakable in quantum mechanics'': "For EPR that would be an unthinkable 'spooky action at a distance'. To avoid such action at a distance they have to attribute, to the space-time regions in question, real properties in advance of observation, correlated properties, which predetermine the outcomes of these particular observations. Since these real properties, fixed in advance of observation, are not contained in quantum formalism, that formalism for EPR is incomplete. It may be correct, as far as it goes, but the usual quantum formalism cannot be the whole story." And again on p. 144 Bell says: "Einstein had no difficulty accepting that affairs in different places could be correlated. What he could not accept was that an intervention at one place could influence, immediately, affairs at the other." Downloaded 5 July 2011 from {{cite book |year=1987 |accessdate=2014-06-14 |title=Speakable and Unspeakable in Quantum Mechanics |first=J. S. |last=Bell |publisher=[[CERN]] |isbn=0521334950 |url=http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20150412044550/http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |archivedate=12 April 2015 |df=dmy-all }}</ref> and argued that the accepted formulation of [[quantum mechanics]] must therefore be incomplete.<br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally<ref name=":0" /><ref name=":1" /><ref name=":2" /> in tests in which polarization or spin of entangled particles were measured at separate locations, statistically violating [[Bell's inequality]]. In earlier tests, it couldn't be absolutely ruled out that the test result at one point could have been [[Loopholes in Bell test experiments|subtly transmitted]] to the remote point, affecting the outcome at the second location.<ref name=":2">Francis, Matthew.<br />
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[https://arstechnica.com/science/2012/10/quantum-entanglement-shows-that-reality-cant-be-local/ Quantum entanglement shows that reality can't be local], ''Ars Technica'', 30 October 2012</ref> However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<ref name=":1">{{cite journal|last1=Matson|first1=John|title=Quantum teleportation achieved over record distances|journal=Nature News|date=13 August 2012|doi=10.1038/nature.2012.11163|s2cid=124852641}}</ref><ref name=":0">{{cite journal<br />
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| title =Bounding the speed of 'spooky action at a distance<br />
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An entangled system is defined to be one whose quantum state cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or superposition, of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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一个纠缠系统被定义为一个量子态不能被分解为其局部成分的态的乘积的系统,也就是说,它们不是单个粒子,而是一个不可分割的整体。在纠缠中,一个组分不能在不考虑其他组分的情况下被完全描述。复合系统的状态总是可以表示为局部组分状态积的和或叠加;如果这个和必然有多个项,它就被纠缠。<br />
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| journal =Physical Review Letters |volume=110 | issue =26 |page=260407<br />
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| year =2013<br />
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Quantum systems can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on methods. Entanglement is broken when the entangled particles decohere through interaction with the environment; for example, when a measurement is made.<br />
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量子系统可以通过各种类型的相互作用而纠缠在一起。为了实验的目的,纠缠可以通过一些方法实现,请参见下面的方法部分。当纠缠的粒子通过与环境的相互作用而退离时,例如在进行测量时,纠缠就被打破了。 <br />
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| arxiv =1303.0614<br />
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| bibcode =2013PhRvL.110z0407Y<br />
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As an example of entanglement: a subatomic particle decays into an entangled pair of other particles. The decay events obey the various conservation laws, and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a spin-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be spin up on some axis, the other, when measured on the same axis, is always found to be spin down. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the singlet state.)<br />
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作为纠缠的一个例子:一个亚原子粒子衰变为一对纠缠的其他粒子。衰变事件遵循各种守恒定律,因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(以便总动量、角动量、能量等在此过程前后保持大致相同)。例如,一个自旋为零的粒子可以衰变为一对自旋为½的粒子。由于衰变前后的总自旋必须为零(角动量守恒),每当第一个粒子在某个轴上被测量到自旋向上时,另一个粒子在同一个轴上被测量时,总是被发现是自旋向下。(这称为自旋反相关情况;如果测量每个自旋的先验概率相等,则称成对处于单线态)。<br />
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| doi = 10.1103/PhysRevLett.110.260407<br />
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| pmid =23848853 | last1 =Yin | first1 =Juan | last2 =Cao | first2 =Yuan | last3 =Yong | first3 =Hai-Lin | last4 =Ren | first4 =Ji-Gang | last5 =Liang | first5 =Hao | last6 =Liao | first6 =Sheng-Kai | last7 =Zhou | first7 =Fei | last8 =Liu | first8 =Chang | last9 =Wu | first9 =Yu-Ping | last10 =Pan | first10 =Ge-Sheng | last11 =Li | first11 =Li | last12 =Liu | first12 =Nai-Le | last13 =Zhang | first13 =Qiang | last14 =Peng | first14 =Cheng-Zhi | last15 =Pan | first15 =Jian-Wei | s2cid =119293698 }}</ref><br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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如果将这两种粒子分开,可以更好地观察到纠缠的特性。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫。现在,如果我们测量其中一个粒子的特性(比如自旋) ,得到一个结果,然后用同样的标准(沿着同样的轴自旋)测量另一个粒子,我们发现第二个粒子的测量结果将匹配(在补充意义上)第一个粒子的测量结果,因为它们的值将相反。<br />
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According to ''some'' [[interpretations of quantum mechanics]], the effect of one measurement occurs instantly. Other interpretations which don't recognize [[wavefunction collapse]] dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces ''[[correlation]]'' between the measurements and that the [[mutual information]] between the entangled particles can be exploited, but that any ''transmission'' of information at faster-than-light speeds is impossible.<ref>[[Roger Penrose]], ''The Road to Reality: A Complete Guide to the Laws of the Universe'', London, 2004, p. 603.</ref><ref name="Griffiths2004">{{citation | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |isbn= 978-0-13-111892-8}}</ref><br />
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根据“一些”[[量子力学的解释]],一次测量的效果瞬间发生。其他不承认[[波函数崩溃]]的解释则认为存在任何“效应”。然而,所有的解释都同意,纠缠在测量值之间产生了“[[相关]]”,并且纠缠粒子之间的[[互信息]]可以被利用,但是任何以高于光速的信息“传输”都是不可能的。 <br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a hidden variable theory (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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上述结果可能会或不会被认为是令人惊讶的。一个经典系统也会表现出同样的性质,而一个隐藏变量理论(见下文)肯定会被要求这样做,它建立在经典力学和量子力学的角动量守恒的基础上。不同的是,一个经典系统对所有的可观测值都有确定的值,而量子系统则没有。在下文将要讨论的意义上,这里所考虑的量子系统似乎在测量第一个粒子时获得了沿另一粒子的任何轴的自旋测量结果的概率分布。这个概率分布通常不同于不测量第一个粒子时的概率分布。对于空间分离的纠缠粒子来说,这无疑是令人惊讶的。<br />
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Quantum entanglement has been demonstrated experimentally with [[photon]]s,<ref name="Kocher1">{{cite journal | doi = 10.1103/PhysRevLett.18.575 | volume=18 | issue=15 | title=Polarization Correlation of Photons Emitted in an Atomic Cascade | journal=Physical Review Letters | pages=575–577 | last1 = Kocher | first1 = CA | last2 = Commins | first2 = ED | year=1967| url=http://www.escholarship.org/uc/item/1kb7660q | bibcode=1967PhRvL..18..575K }}</ref><ref name="Kocherphd">Carl A. Kocher, Ph.D. Thesis (University of California at Berkeley, 1967). ''[https://escholarship.org/uc/item/1kb7660q Polarization Correlation of Photons Emitted in an Atomic Cascade]''</ref> [[neutrino]]s,<ref>J. A. Formaggio, D. I. Kaiser, M. M. Murskyj, and T. E. Weiss (2016), "[https://journals.aps.org/prl/accepted/6f072Y00C3318d41f5739ec7f83a9acf1ad67b002 Violation of the Leggett-Garg inequality in neutrino oscillations]". ''Phys. Rev. Lett.'' Accepted 23 June 2016.</ref> [[electron]]s,<ref name="NTR-20151021">{{cite journal |author=Hensen, B. |title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres |date=21 October 2015 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature15759 |display-authors=etal |volume=526 |issue=7575 |pages=682–686|bibcode = 2015Natur.526..682H |pmid=26503041|arxiv=1508.05949 |hdl=2117/79298 |s2cid=205246446 }} See also [http://www.nature.com/articles/nature15759.epdf?referrer_access_token=1QB20mTNTZW60nEXil0D79RgN0jAjWel9jnR3ZoTv0Pfu6MWINxm4Io03p2jIRZ8qX_3I3N0Kr-AlItuikCZOJrG8QbdRRghlecFwmixlbQpWuw1dtaib4Le5DQOG3u_aXHU85x1JEhOcQTa1sHi0yvW23bblxmEQZAmHL4G0gIVusG_6JWorroY5BprgbTl4FiaE8WltEgMoUMZfZBkEfbMcFDp5iR112TFx_x3ZRj88Wa23E2moEvTfKjtlued0&tracking_referrer=www.nytimes.com free online access version].</ref><ref name="NYT-20151021">{{cite news |last=Markoff |first=Jack |title=Sorry, Einstein. Quantum Study Suggests 'Spooky Action' Is Real. |url=https://www.nytimes.com/2015/10/22/science/quantum-theory-experiment-said-to-prove-spooky-interactions.html |date=21 October 2015 |work=The New York Times |accessdate=21 October 2015 }}</ref> [[molecule]]s as large as [[buckyball]]s,<ref>{{cite journal | doi = 10.1038/44348 | title = Wave–particle duality of C<sub>60</sub> molecules | date= 14 October 1999 | volume=401 | issue = 6754 | journal=Nature | pages=680–682 | pmid=18494170|bibcode = 1999Natur.401..680A | last1 = Arndt | first1 = M | last2 = Nairz | first2 = O | last3 = Vos-Andreae | first3 = J | last4 = Keller | first4 = C | last5 = van der Zouw | first5 = G | last6 = Zeilinger | first6 = A| s2cid = 4424892 }} {{subscription}}</ref><ref>[[Olaf Nairz]], [[Markus Arndt]], and [[Anton Zeilinger]], "Quantum interference experiments with large molecules", American Journal of Physics, 71 (April 2003) 319–325.</ref> and even small diamonds.<ref>{{cite journal |journal=Science |date=2 December 2011 |volume=334 |issue=6060 |pages=1253–1256 |doi=10.1126/science.1211914 |pmid=22144620 |url=http://www.sciencemag.org/content/334/6060/1253.full |title=Entangling macroscopic diamonds at room temperature |lay-url=https://www.newscientist.com/article/dn21235-entangled-diamonds-blur-quantumclassical-divide.html|bibcode = 2011Sci...334.1253L |last1=Lee |first1=K. C. |last2=Sprague |first2=M. R. |last3=Sussman |first3=B. J. |last4=Nunn |first4=J. |last5=Langford |first5=N. K. |last6=Jin |first6=X.- M. |last7=Champion |first7=T. |last8=Michelberger |first8=P. |last9=Reim |first9=K. F. |last10=England |first10=D. |last11=Jaksch |first11=D. |last12=Walmsley |first12=I. A. |s2cid=206536690 }}</ref><ref>[http://www.sciencemag.org/content/334/6060/1253/suppl/DC1 sciencemag.org], supplementary materials</ref> The utilization of entanglement in [[quantum communication|communication]], [[quantum computing|computation]] and [[quantum radar]] is a very active area of research and development.<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<br />
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矛盾之处在于,对任一粒子的测量显然会使整个纠缠系统的状态崩溃,而且会瞬间崩溃,在关于测量结果的任何信息可以被传送到另一个粒子之前(假设信息不能比光传播得快),因此确保纠缠对的另一部分的测量结果是“正确的”。在哥本哈根解释中,对其中一个粒子的自旋测量的结果是坍缩成一种状态,其中每个粒子沿测量轴都有一个确定的自旋(向上或向下)。结果是随机的,每种可能性的概率为50%。然而,如果两个自旋沿同一轴测量,就会发现它们是反相关的。这意味着,对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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== History 历史==<br />
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[[File:NYT May 4, 1935.jpg|right|thumb| 250px|Article headline regarding the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox) paper, in the May 4, 1935 issue of ''[[The New York Times]]''.]]<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, hence, any causal effect connecting the events would have to travel faster than light. According to the principles of special relativity, it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events and there are inertial frames in which is first and others in which is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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可以选择测量的距离和时间,使两个测量之间的间隔类似于空间,因此,任何连接事件的因果效应都必须比光传播得更快。根据狭义相对论原理,任何信息都不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量结果是最先出现的。对于两个类空分离的事件,存在惯性系,其中一个是第一个,其他的是第一个。因此,两个测量值之间的相关性不能解释为一个测量值决定另一个测量值: 不同的观察者会对因果的作用有不同的看法。<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by [[Albert Einstein]] in 1935, in a joint paper with [[Boris Podolsky]] and [[Nathan Rosen]].<ref name="Einstein1935"/><br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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(事实上,即使没有纠缠也会出现类似的悖论: 单个粒子的位置分布在空间上,两个相距很远的探测器试图在两个不同的地方探测粒子,必须同时达到适当的相关性,以便它们不能同时探测粒子。)<br />
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In this study, the three formulated the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox), a [[thought experiment]] that attempted to show that [[quantum mechanics|quantum mechanical theory]] was [[Incompleteness of quantum physics|incomplete]]. They wrote: "We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete."<ref name="Einstein1935"/><br />
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However, the three scientists did not coin the word ''entanglement'', nor did they generalize the special properties of the state they considered. Following the EPR paper, [[Erwin Schrödinger]] wrote a letter to Einstein in [[German language|German]] in which he used the word ''Verschränkung'' (translated by himself as ''entanglement'') "to describe the correlations between two particles that interact and then separate, as in the EPR experiment."<ref name=MK>Kumar, M., ''Quantum'', Icon Books, 2009, p. 313.</ref><br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables". The state of the particles being measured contains some hidden variables, whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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这一悖论的一个可能的解决办法是假定量子理论是不完整的,测量结果取决于预先确定的“隐变量”。被测粒子的状态包含一些隐藏的变量,它们的值有效地决定了,从分离的那一刻起,自旋测量的结果将会是什么。这意味着每个粒子都携带着所需的所有信息,在测量时不需要从一个粒子传递到另一个粒子。爱因斯坦和其他人(见上一节)最初认为这是唯一的出路的悖论,和公认的量子力学描述(随机测量结果)必须是不完整的。<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated:<ref name="Schrödinger1935"/> "I would not call [entanglement] ''one'' but rather ''the'' characteristic trait of [[quantum mechanics]], the one that enforces its entire departure from [[Classical mechanics|classical]] lines of thought."<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the local realist or hidden variables view were correct, the results would always satisfy Bell's inequality. A number of experiments have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists. When measurements of the entangled particles are made in moving relativistic reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<br />
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然而,当考虑沿不同轴线的纠缠粒子的自旋时,局部隐变量理论就失败了。如果在大量的纠缠粒子对上进行了大量的这样的测量,那么从统计学上来说,如果局域实在论或隐变量观点是正确的,那么结果总是满足 Bell 不等式。许多实验表明,贝尔不等式在实践中并不能得到满足。然而,在2015年之前,所有这些都存在漏洞问题,这被物理学界认为是最重要的。当在移动的相对论参照系中测量纠缠粒子时,每个测量(在其自身的相对论时间框架内)先于另一个进行,测量结果仍然是相关的。<br />
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Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the [[theory of relativity]].<ref>Alisa Bokulich, Gregg Jaeger, ''Philosophy of Quantum Information and Entanglement'', Cambridge University Press, 2010, xv.</ref> Einstein later famously derided entanglement as "''spukhafte Fernwirkung''"<ref name="spukhafte">Letter from Einstein to Max Born, 3 March 1947; ''The Born-Einstein Letters; Correspondence between Albert Einstein and Max and Hedwig Born from 1916 to 1955'', Walker, New York, 1971. (cited in {{citation | title = Quantum Entanglement and Communication Complexity (1998) | journal = SIAM J. Comput. | volume = 30 | issue = 6 | citeseerx = 10.1.1.20.8324 | author = M. P. Hobson |pages=1829–1841 | display-authors = etal | year = 1998 }})</ref> or "spooky [[Action at a distance (physics)|action at a distance]]."<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are incompatible in the sense that these measurements' maximum simultaneous precision is constrained by the uncertainty principle. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations, and thus entanglement is a fundamentally non-classical phenomenon.<br />
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沿不同轴线测量自旋的基本问题是,这些测量不可能同时具有确定的值——它们是不相容的,因为这些测量的最大同时精度受到不确定性原理的限制。这与经典物理学中的发现相反,在经典物理学中,任何数量的性质都可以以任意精度同时测量。从数学上证明了相容测量不能显示违反贝尔不等式的关联,因此纠缠是一个基本的非经典现象。<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously [[De Broglie–Bohm theory|Bohm's interpretation]] of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when [[John Stewart Bell]] proved that one of their key assumptions, the [[principle of locality]], as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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Entanglement is required to preserve the Uncertainty principle, as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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纠缠是保持不确定性原理所必需的,如 EPR 悖论所示。例如,假设一个高能光子衰变成一个电子/正电子对,然后测量电子的位置和正电子的动量。如果我们在物理描述中不允许纠缠,那么每个粒子的位置和动量仍然可以通过参考动量守恒来推导,这违反了测不准原理。或者,如果我们要求不确定性原理保持真实,而仍然不允许在物理描述对的纠缠,不确定性原理将允许违反动量守恒定律,因为在位置和动量上强相关性是不可能的(也就是说,人们不能有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关)。--><br />
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Specifically, Bell demonstrated an upper limit, seen in [[Bell's inequality]], regarding the strength of correlations that can be produced in any theory obeying [[local realism]], and showed that quantum theory predicts violations of this limit for certain entangled systems.<ref>{{cite journal |author = J. S. Bell |title = On the Einstein-Poldolsky-Rosen paradox |journal = Physics Physique Физика |volume = 1 |issue = 3 |pages = 195–200 |year = 1964|doi = 10.1103/PhysicsPhysiqueFizika.1.195 |doi-access = free }}</ref> His inequality is experimentally testable, and there have been numerous [[Bell test experiments|relevant experiments]], starting with the pioneering work of [[Stuart Freedman]] and [[John Clauser]] in 1972<ref name="Clauser">{{cite journal|doi=10.1103/PhysRevLett.28.938|last1=Freedman|first1=Stuart J.|last2=Clauser|first2=John F.|title=Experimental Test of Local Hidden-Variable Theories|journal=Physical Review Letters |volume=28 |issue=14 |pages=938–941|year=1972 |bibcode=1972PhRvL..28..938F|url=https://escholarship.org/uc/item/2f18n5nk}}</ref> and [[Alain Aspect]]'s experiments in 1982.<ref>{{cite journal |author1=A. Aspect |author2=P. Grangier |author3=G. Roger |name-list-style=amp |title = Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell's Inequalities |journal = Physical Review Letters |volume = 49 |issue = 2 |pages = 91–94 |year = 1982 |doi = 10.1103/PhysRevLett.49.91 |bibcode=1982PhRvL..49...91A|doi-access = free }}</ref> An early experimental breakthrough was due to Carl Kocher,<ref name="Kocher1"/><ref name="Kocherphd"/> who already in 1967 presented an apparatus in which two photons successively emitted from a calcium atom were shown to be entangled – the first case of entangled visible light. The two photons passed diametrically positioned parallel polarizers with higher probability than classically predicted but with correlations in quantitative agreement with quantum mechanical calculations. He also showed that the correlation varied only upon (as cosine square of) the angle between the polarizer settings<ref name="Kocherphd"/> and decreased exponentially with time lag between emitted photons.<ref name="Kocher2">{{cite journal | doi = 10.1016/0003-4916(71)90159-X | volume=65 | issue=1 | title=Time correlations in the detection of successively emitted photons | journal=Annals of Physics | pages=1–18 | last1 = Kocher | first1 = CA | year=1971| bibcode=1971AnPhy..65....1K }}</ref> Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles.<ref name="Clauser"/> All these experiments have shown agreement with quantum mechanics rather than the principle of local realism.<br />
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For decades, each had left open at least one [[Loopholes in Bell test experiments|loophole]] by which it was possible to question the validity of the results. However, in 2015 an experiment was performed that simultaneously closed both the detection and locality loopholes, and was heralded as "loophole-free"; this experiment ruled out a large class of local realism theories with certainty.<ref name="hanson">{{cite journal|last1=Hanson|first1=Ronald|title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres|journal=Nature|volume=526|issue=7575|pages=682–686|doi=10.1038/nature15759|arxiv=1508.05949|bibcode = 2015Natur.526..682H|pmid=26503041|year=2015|s2cid=205246446}}</ref> [[Alain Aspect]] notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / ''[[superdeterminism]]'' loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<ref>{{Cite journal | title=Viewpoint: Closing the Door on Einstein and Bohr's Quantum Debate| journal=Physics| volume=8| date=2015-12-16| last1=Aspect| first1=Alain| page=123| doi=10.1103/physics.8.123| doi-access=free| bibcode=2015PhyOJ...8..123A}}</ref><br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time. The authors claimed that this result was achieved by entanglement swapping between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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在2012年和2013年的实验中,光子之间产生了偏振相关性,这种相关性从未在时间上共存过。作者认为,这一结果是通过测量早期纠缠光子对中一个光子的偏振态后,两对纠缠光子之间的纠缠交换实现的,并且证明了量子非局域性不仅适用于空间,也适用于时间。<br />
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A minority opinion holds that although quantum mechanics is correct, there is no [[faster-than-light|superluminal]] instantaneous action-at-a-distance between entangled particles once the particles are separated.<ref>{{Cite journal |doi = 10.1142/S0217979206034078|title = Correlations in Entangled States|journal = International Journal of Modern Physics B|volume = 20|issue = 11n13|pages = 1496–1503|year = 2006|last1 = Sanctuary|first1 = B. C|arxiv = quant-ph/0508238|bibcode = 2006IJMPB..20.1496S|s2cid = 119403050}}</ref><ref>{{Cite arxiv |eprint = quant-ph/0404011 |last1 = Yin |first1 = Juan |title = The Statistical Interpretation of Entangled States |last2 = Cao |first2 = Yuan |last3 = Yong |first3 = Hai-Lin |last4 = Ren |first4 = Ji-Gang |last5 = Liang |first5 = Hao |last6 = Liao |first6 = Sheng-Kai |last7 = Zhou |first7 = Fei |last8 = Liu |first8 = Chang |last9 = Wu |first9 = Yu-Ping |last10 = Pan |first10 = Ge-Sheng |last11 = Zhang |first11 = Qiang |last12 = Peng |first12 = Cheng-Zhi |last13 = Pan |first13 = Jian-Wei |year = 2004 }}</ref><ref>{{cite journal|doi=10.1002/prop.201600044 | volume=65 | issue=6–8 | title=After Bell | year=2016 | journal=Fortschritte der Physik | page=1600044 | last1 = Khrennikov | first1 = Andrei}}</ref><ref>{{Cite journal |arxiv = 1603.08674|last1 = Yin|first1 = Juan|title = After Bell|journal = Fortschritte der Physik (Progress in Physics)|date=2017|volume = 65|issue = 1600014|pages = 6–8|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|bibcode = 2016arXiv160308674K}}</ref><ref>{{Cite journal |arxiv = quant-ph/0703251|last1 = Yin|first1 = Juan|title = Classical statistical distributions can violate Bell-type inequalities|journal = Journal of Physics A: Mathematical and Theoretical|volume = 41|issue = 8|pages = 085303|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|year = 2007|doi = 10.1088/1751-8113/41/8/085303|s2cid = 46193162}}</ref><br />
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In three independent experiments in 2013 it was shown that classically communicated separable quantum states can be used to carry entangled states. The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<br />
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在2013年的三个独立实验中,我们发现经典通信的可分离量子态可以用来携带纠缠态。2015年,TU Delft 进行了第一次没有漏洞的贝尔测试,证实了贝尔不平等的违规性。<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of [[quantum key distribution]] protocols, most famously [[BB84]] by [[Charles H. Bennett (computer scientist)|Charles H. Bennett]] and [[Gilles Brassard]]<ref>C. H. Bennett and G. Brassard. "Quantum cryptography: Public key distribution and coin tossing". In ''Proceedings of IEEE International Conference on Computers, Systems and Signal Processing'', volume 175, p. 8. New York, 1984. http://researcher.watson.ibm.com/researcher/files/us-bennetc/BB84highest.pdf</ref> and [[E91 protocol|E91]] by [[Artur Ekert]].<ref>{{cite journal|last=Ekert|first=A.K.|authorlink=Artur Ekert|title=Quantum cryptography based on Bell's theorem|journal=Phys. Rev. Lett.|volume=67|issue=6|year=1991|doi=10.1103/PhysRevLett.67.661|issn=0031-9007|bibcode = 1991PhRvL..67..661E|pmid=10044956|pages=661–663}}</ref> Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<br />
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2014年8月,巴西研究人员加布里埃拉 · 巴雷托 · 莱莫斯和他的团队能够使用光子“拍摄”物体,这些光子并没有与实验对象发生相互作用,而是与这些物体发生了纠缠。来自维也纳大学的勒莫斯相信,这种新的量子成像技术可以在微光成像势在必行的领域找到应用,比如生物或医学成像。<br />
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== Concept ==<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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2015年,哈佛大学的 Markus Greiner 团队直接测量了超冷玻色子原子系统中的 Renyi 纠缠。<br />
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=== Meaning of entanglement ===<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<br />
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从2016年开始,各种各样的公司,如 IBM,微软等。已经成功地创造了量子计算机,并且允许开发者和技术爱好者公开地实验量子力学的概念,包括量子纠缠。<br />
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An entangled system is defined to be one whose [[quantum state]] cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or [[quantum superposition|superposition]], of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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Quantum [[physical system|systems]] can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on [[#Methods of creating entanglement|methods]]. Entanglement is broken when the entangled particles [[quantum decoherence|decohere]] through interaction with the environment; for example, when a measurement is made.<ref name="Peres1993">Asher Peres, ''[[Quantum Theory: Concepts and Methods]]'', Kluwer, 1993; {{ISBN|0-7923-2549-4}} p. 115.</ref><br />
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There have been suggestions to look at the concept of time as an emergent phenomenon that is a side effect of quantum entanglement.<br />
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有人建议把时间的概念看作是量子纠缠的副作用的一种自然现象。<br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by Don Page and William Wootters in 1983.<br />
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换句话说,时间是一种纠缠现象,它将所有相同的时钟读数(正确准备的时钟,或任何可用作时钟的物体)置于同一历史中。这是唐 · 佩奇和威廉 · 伍特斯在1983年首次提出的完整理论。<br />
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As an example of entanglement: a [[subatomic particle]] [[Particle decay|decays]] into an entangled pair of other particles. The decay events obey the various [[conservation laws]], and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a [[Spin (physics)|spin]]-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be [[Spin (physics)#Direction|spin up]] on some axis, the other, when measured on the same axis, is always found to be [[Spin (physics)#Direction|spin down]]. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the [[singlet state]].)<br />
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The Wheeler–DeWitt equation that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<br />
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20世纪60年代,惠勒-德威特方程引入了广义相对论和量子力学的概念,并于1983年再次引入,当时佩奇和伍特基于量子纠缠方程提出了一个解决方案。佩奇和伍特斯认为纠缠态可以用来测量时间。<br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts. The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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2013年,在意大利都灵的国家理查尔卡计量研究所(INRIM) ,研究人员对佩奇和伍特的想法进行了首次实验测试。他们的结果被解释为证实了对于内部观察者来说时间是一种涌现的现象,但正如惠勒-德威特方程所预测的那样,对于宇宙的外部观察者来说时间是不存在的。纠缠的方法是从因果时间箭头的角度出发,假设一个粒子被测量的原因决定了另一个粒子测量结果的影响。<br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a [[hidden variable theory]] (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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===Paradox===<br />
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Based on AdS/CFT correspondence, Mark Van Raamsdonk suggested that spacetime arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time. Induced gravity can emerge from the entanglement first law.<br />
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基于 AdS/CFT对偶的理论,Mark Van Raamsdonk 提出时空是作为量子自由度的一种涌现现象而产生的,这种量子自由度是纠缠在一起的,生活在时空的边界上。诱导引力可以产生于纠缠第一定律。<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel [[faster than light]]) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the [[Copenhagen interpretation]], the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<ref>{{cite book|last1=Rupert W.|first1=Anderson|title=The Cosmic Compendium: Interstellar Travel|date=28 March 2015|publisher=The Cosmic Compendium|isbn=9781329022027|page=100|edition=First|url=https://books.google.com/books?id=JxauCQAAQBAJ&pg=PA100&lpg=PA100&dq=The+outcome+is+taken+to+be+random,+with+each+possibility+having+a+probability+of+50%25.+However,+if+both+spins+are+measured+along+the+same+axis,+they+are+found+to+be+anti-correlated.+This+means+that+the+random+outcome+of+the+measurement+made+on+one+particle+seems+to+have+been+transmitted+to+the+other,+so+that+it+can+make+the+%22right+choice%22+when+it+too+is+measured#v=onepage}}</ref><br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements [[spacelike]], hence, any causal effect connecting the events would have to travel faster than light. According to the principles of [[special relativity]], it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events {{math|''x''<sub>1</sub>}} and {{math|''x''<sub>2</sub>}} there are [[inertial frame]]s in which {{math|''x''<sub>1</sub>}} is first and others in which {{math|''x''<sub>2</sub>}} is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations. A well-known example is the Werner states that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables. Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<br />
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在媒体和流行科学中,量子非定域性经常被描述为等价于纠缠。虽然这对于纯二体量子态来说是正确的,但是一般来说纠缠只对于非局域关联是必要的,但是存在混合纠缠态,不产生这样的关联。一个众所周知的例子是 Werner 状态,它纠缠于 < math > p _ { sym } </math > 的某些值,但总是可以使用局部隐变量来描述。此外,研究还表明,对于任意数目的当事人,存在真正纠缠但承认局部模型的状态。<br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all distillable states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<br />
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上述关于局域模型存在性的证明假设一次只有一个量子态的副本可用。如果允许各方对这些状态的许多副本进行局部测量,那么许多表面上的局部状态(例如,量子位维尔纳状态)就不能再用局部模型来描述。对于所有的可提取态来说,情况尤其如此。然而,如果给定足够多的副本,是否所有纠缠态都成为非局域态,这仍然是一个有待解决的问题。<br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to quantum teleportation and to superdense coding, whereas non-locality is defined according to experimental statistics and is much more involved with the foundations and interpretations of quantum mechanics.<br />
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简而言之,双方共享的态的纠缠是必要的,但不足以使该态成为非局域态。重要的是要认识到纠缠通常被看作是一个代数概念,因为它是非定域性以及量子遥传和超密编码的先决条件,而非定域性是根据实验统计数据定义的,更多地涉及到基础和量子力学诠释。<br />
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=== Hidden variables theory ===<br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables".<ref>{{Cite news|url=https://www.scientificamerican.com/article/cosmic-test-bolsters-einsteins-ldquo-spooky-action-at-a-distance-rdquo/?WT.mc_id=SA_FB_PHYS_NEWS|title=Cosmic Test Bolsters Einstein's "Spooky Action at a Distance"|last=magazine|first=Elizabeth Gibney, Nature|newspaper=Scientific American|language=en|access-date=2017-02-04}}</ref> The state of the particles being measured contains some [[hidden-variable theory|hidden variables]], whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of quantum mechanics, including familiarity with the formalism and theoretical framework developed in the articles: bra–ket notation and mathematical formulation of quantum mechanics.<br />
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下面的小节适合那些对量子力学的形式和数学描述有良好工作知识的人,包括对文章中开发的形式主义和理论框架的熟悉: bra-ket 符号和量子力学的数学表述。<br />
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=== Violations of Bell's inequality ===<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the [[local realism|local realist]] or hidden variables view were correct, the results would always satisfy [[Bell's inequality]]. A [[Bell test experiments|number of experiments]] have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists.<ref>{{citation |author1=I. Gerhardt |author2=Q. Liu |author3=A. Lamas-Linares |author4=J. Skaar |author5=V. Scarani |author6=V. Makarov |author7=C. Kurtsiefer |year=2011 |title=Experimentally faking the violation of Bell's inequalities |journal=Phys. Rev. Lett. |volume=107 |issue=17 |page=170404 |arxiv=1106.3224 |doi=10.1103/PhysRevLett.107.170404 |bibcode=2011PhRvL.107q0404G |pmid=22107491|s2cid=16306493 }}</ref><ref>{{cite journal | last1 = Santos | first1 = E | year = 2004 | title = The failure to perform a loophole-free test of Bell's Inequality supports local realism | url = | journal = Foundations of Physics | volume = 34 | issue = 11| pages = 1643–1673 | doi=10.1007/s10701-004-1308-z|bibcode = 2004FoPh...34.1643S | s2cid = 123642560 }}</ref> When measurements of the entangled particles are made in moving [[special relativity|relativistic]] reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<ref>{{cite journal |author = H. Zbinden |title = Experimental test of nonlocal quantum correlations in relativistic configurations |journal = Phys. Rev. A |volume = 63 |issue = 2 |pages = 22111 |doi = 10.1103/PhysRevA.63.022111|year = 2001|arxiv = quant-ph/0007009 |bibcode = 2001PhRvA..63b2111Z |display-authors = 1 |last2 = Gisin |last3 = Tittel |s2cid = 44611890 |url = http://archive-ouverte.unige.ch/unige:37034 }}</ref><ref name=LG>Some of the history of both referenced Zbinden, et al. experiments is provided in Gilder, L., ''The Age of Entanglement'', Vintage Books, 2008, pp. 321–324.</ref><br />
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Consider two arbitrary quantum systems and , with respective Hilbert spaces and . The Hilbert space of the composite system is the tensor product<br />
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考虑两个任意的量子系统和,分别具有希尔伯特空间和。复合系统的 Hilbert 空间是张量积<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are [[Incompatible observables|incompatible]] in the sense that these measurements' maximum simultaneous precision is constrained by the [[uncertainty principle]]. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations,<ref>{{cite journal|last1=Cirel'son|first1=B. S.|title=Quantum generalizations of Bell's inequality|journal=Letters in Mathematical Physics|volume=4|issue=2|pages=93–100| year=1980|doi=10.1007/BF00417500|bibcode=1980LMaPh...4...93C|s2cid=120680226}}</ref> and thus entanglement is a fundamentally non-classical phenomenon.<br />
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<math> H_A \otimes H_B.</math><br />
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Entanglement is required to preserve the [[Uncertainty principle]], as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态 < math > scriptstyle | psi rangle _ a </math > ,而第二个系统处于状态 < math > scriptstyle | phi rangle _ b </math > ,则复合系统的状态为<br />
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=== Other types of experiments ===<br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time.<ref name="Xiao-song2012">{{cite journal |author=Xiao-song Ma, Stefan Zotter, Johannes Kofler, Rupert Ursin, Thomas Jennewein, Časlav Brukner & Anton Zeilinger |title=Experimental delayed-choice entanglement swapping |journal=Nature Physics |volume=8 |issue=6 |pages=480–485 |date=26 April 2012 |doi=10.1038/nphys2294|arxiv = 1203.4834 |bibcode = 2012NatPh...8..480M |last2=Zotter |last3=Kofler |last4=Ursin |last5=Jennewein |last6=Brukner |last7=Zeilinger |s2cid=119208488 }}</ref><ref>{{cite journal | last1 = Megidish | first1 = E. | last2 = Halevy | first2 = A. | last3 = Shacham | first3 = T. | last4 = Dvir | first4 = T. | last5 = Dovrat | first5 = L. | last6 = Eisenberg | first6 = H. S. | year = 2013 | title = Entanglement Swapping between Photons that have Never Coexisted | url = | journal = Physical Review Letters | volume = 110 | issue = 21| page = 210403| doi=10.1103/physrevlett.110.210403|arxiv = 1209.4191 |bibcode = 2013PhRvL.110u0403M | pmid=23745845| s2cid = 30063749 }}</ref> The authors claimed that this result was achieved by [[Quantum teleportation#Entanglement swapping|entanglement swapping]] between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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<math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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In three independent experiments in 2013 it was shown that [[classical physics|classically communicated]] [[separable state|separable quantum states]] can be used to carry entangled states.<ref>{{cite web|url=http://physicsworld.com/cws/article/news/2013/dec/11/classical-carrier-could-create-entanglement |title=Classical carrier could create entanglement |publisher=physicsworld.com |accessdate=2014-06-14|date=2013-12-11 }}</ref> The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<ref>{{cite web | url=http://hansonlab.tudelft.nl/loophole-free-bell-test/ | title=Loophole-free Bell test &#124; Ronald Hanson | access-date=24 October 2015 | archive-url=https://web.archive.org/web/20180704082456/http://hansonlab.tudelft.nl/loophole-free-bell-test/ | archive-date=4 July 2018 | url-status=dead }}</ref><br />
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States of the composite system that can be represented in this form are called separable states, or product states.<br />
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可以用这种形式表示的复合系统状态称为可分状态或乘积状态。<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<ref>{{Cite journal|url=http://www.nature.com/news/entangled-photons-make-a-picture-from-a-paradox-1.15781|title=Entangled photons make a picture from a paradox|journal=Nature|accessdate=13 October 2014|doi=10.1038/nature.2014.15781|year=2014|last1=Gibney|first1=Elizabeth|s2cid=124976589}}</ref><br />
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Not all states are separable states (and thus product states). Fix a basis <math>\scriptstyle \{|i \rangle_A\}</math> for and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for . The most general state in is of the form<br />
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并非所有状态都是可分状态(因此也就是乘积状态)。修复一个基础 < math > scriptstyle { | i rangle _ a } </math > for 和一个基础 < math > scriptstyle { | j rangle _ b } </math > for。最普遍的状态是形式<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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<math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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[数学] | psi rangle { AB } = sum { i,j } c { ij } | i rangle _ a otimes | j rangle _ b </math > 。<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<ref>{{Cite journal|last=Rozatkar|first=Gaurav|date=2018-08-16|title=Demonstration of quantum entanglement|url=https://osf.io/g8bpj/|journal=OSF|language=en}}</ref><br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > ,那么这种状态是可分的,因此 < math scriptstyle c { ij } = c ^ a _ ic ^ b _ j,</math > 产生 < math scriptstyle | psi rangle _ a = sum { i } c ^ a _ { i } | i } | i _ a </math > 和 < math > phi scriptstyle | b = sum { j } | j } | j rangle b = sum { j }。如果对于任何向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > 至少对于一对坐标 < math > scriptstyle c ^ a _ i,c ^ b _ j </math > 我们有 < math > scriptstyle c _ { ij } neq c ^ a _ ic ^ b _ j。如果一种状态是不可分割的,那么它被称为“纠缠态”。<br />
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=== Mystery of time ===<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of , the following is an entangled state:<br />
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例如,给定两个基向量{ | 0 rangle _ a,| 1 rangle _ a } </math > 和两个基向量{ | 0 rangle _ b,| 1 rangle _ b } </math > ,下面是一个纠缠态:<br />
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There have been suggestions to look at the concept of time as an [[emergent phenomenon]] that is a side effect of quantum entanglement.<ref>{{Cite journal|title= Time from quantum entanglement: an experimental illustration|arxiv=1310.4691|bibcode = 2014PhRvA..89e2122M |doi = 10.1103/PhysRevA.89.052122|volume=89|issue= 5|pages=052122|journal=Physical Review A|year=2014 | last1 = Moreva | first1 = Ekaterina|s2cid=118638346}}</ref><ref>{{cite web|url=https://www.newscientist.com/article/dn24473-entangled-toy-universe-shows-time-may-be-an-illusion.html#.U8_-ApSSx2A|title=Entangled toy universe shows time may be an illusion|publisher=|accessdate=13 October 2014}}</ref><br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by [[Don Page (physicist)|Don Page]] and [[William Wootters]] in 1983.<ref>David Deutsch, The Beginning of infinity. Page 299</ref><br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right)<br />
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The [[Wheeler–DeWitt equation]] that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<ref name="medium.com">{{cite web|url=https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933|title=Quantum Experiment Shows How Time 'Emerges' from Entanglement|website=Medium|accessdate=13 October 2014|date=2013-10-23}}</ref><br />
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If the composite system is in this state, it is impossible to attribute to either system or system a definite pure state. Another way to say this is that while the von Neumann entropy of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry. The above example is one of four Bell states, which are (maximally) entangled pure states (pure states of the space, but which cannot be separated into pure states of each and ).<br />
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如果组合系统处于这种状态,就不可能给任何一个系统或系统一个确定的纯状态。另一种说法是,尽管整个状态的冯纽曼熵为零(对于任何纯状态都是如此) ,但子系统的熵大于零。从这个意义上说,这两个系统是“纠缠”的。这对干涉测量法有具体的经验影响。上面的例子是四个贝尔态之一,它们是(最大)纠缠纯态(空间的纯态,但不能分离成每个和的纯态)。<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted{{by whom|date=August 2020}} to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts.<ref name="medium.com"/><br />
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Now suppose Alice is an observer for system , and Bob is an observer for system . If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of , there are two possible outcomes, occurring with equal probability:<br />
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现在假设 Alice 是系统的观察者,而 Bob 是系统的观察者。如果在上面给出的纠缠态中,爱丽丝在[ | 0 rangle,| 1 rangle ] </math 本征基中进行测量,有两种可能的结果,发生的概率相等:<br />
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=== Source for the arrow of time ===<br />
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Physicist [[Seth Lloyd]] says that [[quantum uncertainty]] gives rise to entanglement, the putative source of the [[arrow of time]]. According to Lloyd; "The arrow of time is an arrow of increasing correlations."<ref>{{Cite journal|url=https://www.wired.com/2014/04/quantum-theory-flow-time/|title=New Quantum Theory Could Explain the Flow of Time|journal=Wired|accessdate=13 October 2014|date=2014-04-25|last1=Wolchover|first1=Natalie}}</ref> The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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Alice 测量0,系统的状态崩溃为 < math > scriptstyle | 0 rangle _ a | 1 rangle _ b </math > 。<br />
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Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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Alice 测量1,系统的状态崩溃为 < math > scriptstyle | 1 rangle _ a | 0 rangle _ b </math > 。<br />
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=== Emergent gravity ===<br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system has been altered by Alice performing a local measurement on system . This remains true even if the systems and are spatially separated. This is the foundation of the EPR paradox.<br />
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如果前者发生,那么 Bob 在相同基础上执行的任何后续测量都将返回1。如果出现后一种情况,(Alice 度量1) ,那么 Bob 的度量将确定返回0。因此,Alice 对系统进行了本地测量,从而对系统进行了更改。即使系统和空间上是分开的,这也是正确的。这就是 EPR 悖论的基础。<br />
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Based on [[AdS/CFT correspondence]], [[Mark Van Raamsdonk]] suggested that [[spacetime]] arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time.<ref>{{Cite journal|last=Van Raamsdonk|first=Mark|date=2010-06-19|title=Building up spacetime with quantum entanglement|journal=General Relativity and Gravitation|language=en|volume=42|issue=10|pages=2323–2329|doi=10.1007/s10714-010-1034-0|issn=0001-7701|arxiv=1005.3035|bibcode=2010GReGr..42.2323V}}</ref> [[Induced gravity]] can emerge from the entanglement first law.<ref>{{Cite journal|last1=Lee|first1=Jae-Weon|last2=Kim|first2=Hyeong-Chan|last3=Lee|first3=Jungjai|date=2013|title=Gravity from quantum information|journal=Journal of the Korean Physical Society|language=en|volume=63|issue=5|pages=1094–1098|doi=10.3938/jkps.63.1094|issn=0374-4884|arxiv=1001.5445|bibcode=2013JKPS...63.1094L|s2cid=118494859}}</ref><ref>{{cite arxiv|last1=Swingle|first1=Brian|last2=Van Raamsdonk|first2=Mark|date=2014-05-12|title=Universality of Gravity from Entanglement|eprint=1405.2933 |class=hep-th}}</ref><br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem.<br />
<br />
爱丽丝的测量结果是随机的。Alice 不能决定将组合系统折叠到哪个状态,因此不能通过作用于她的系统将信息传递给 Bob。因此,在这个特定的方案中,因果关系被保留了下来。关于一般的论点,请参阅不交流定理。<br />
<br />
== Non-locality and entanglement ==<br />
<br />
In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations.<ref name="Brunner-RMP2014">{{cite journal |title=Bell nonlocality |author1=Nicolas Brunner |author2=Daniel Cavalcanti |author3=Stefano Pironio |author4=Valerio Scarani |author5=Stephanie Wehner |journal=Rev. Mod. Phys. |volume=86 |issue=2 |pages=419–478 |date=2014 |doi=10.1103/RevModPhys.86.419 |arxiv=1303.2849|bibcode=2014RvMP...86..419B |s2cid=119194006 }}</ref> A well-known example is the [[Werner state]]s that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables.<ref name=werner1989>{{cite journal | last = Werner| first = R.F. | title = Quantum States with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model | journal = [[Physical Review A]] | volume = 40| pages = 4277–4281 | year = 1989 |doi=10.1103/PhysRevA.40.4277 | pmid=9902666 | issue=8|bibcode = 1989PhRvA..40.4277W }}</ref> Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<ref>{{cite journal|author=R. Augusiak, M. Demianowicz, J. Tura and A. Acín |title=Entanglement and Nonlocality are Inequivalent for Any Number of Parties |journal=Phys. Rev. Lett. |volume=115 |issue=3 |pages=030404 |year=2015 |arxiv=1407.3114 |doi=10.1103/PhysRevLett.115.030404|pmid=26230773 |hdl=2117/78836 |bibcode=2015PhRvL.115c0404A |s2cid=29758483 }}</ref><br />
<br />
The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all [[entanglement distillation|distillable]] states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<ref>{{cite journal |title=Disproving the Peres conjecture: Bell nonlocality from bipartite bound entanglement |authors=Tamas Vértesi, Nicolas Brunner|year=2014 |journal=Nature Communications |volume=5 |issue=5297|page=5297 |doi=10.1038/ncomms6297 |pmid=25370352|arxiv=1405.4502 |s2cid=5135148}}</ref><br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a density matrix, which is a positive-semidefinite matrix, or a trace class when the state space is infinite-dimensional, and has trace 1. Again, by the spectral theorem, such a matrix takes the general form:<br />
<br />
如上所述,量子系统的状态是由希尔伯特空间中的单位向量给出的。更一般地说,如果一个人对系统的了解较少,那么他就称之为“集合” ,并用密度矩阵来描述它,密度矩阵是正半定矩阵,或者当状态空间是无限维且迹1时,用迹类来描述它。同样的,在谱定理,这样的矩阵采取了一般的形式:<br />
<br />
<br />
<br />
In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to [[quantum teleportation]] and to [[superdense coding]], whereas non-locality is defined according to experimental statistics and is much more involved with the [[Quantum foundations|foundations]] and [[interpretations of quantum mechanics]].<ref>In the literature "non-locality" is sometimes used to characterize concepts that differ from the non-existence of a local hidden variable model, e.g., whether states can be distinguished by local measurements and which can occur also for non-entangled states (see, e.g., {{cite journal |authors=Charles H. Bennett, David P. DiVincenzo, Christopher A. Fuchs, Tal Mor, Eric Rains, Peter W. Shor, John A. Smolin, and William K. Wootters |title=Quantum nonlocality without entanglement |journal=Phys. Rev. A |volume=59 |issue=2 |pages=1070–1091 |year=1999 |doi=10.1103/PhysRevA.59.1070 |arxiv= quant-ph/9804053|bibcode=1999PhRvA..59.1070B |s2cid=15282650 }}). This non-standard use of the term is not discussed here.</ref><br />
<br />
<math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
我不知道,我不知道,我不知道<br />
<br />
<br />
<br />
== Quantum mechanical framework ==<br />
<br />
where the w<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret as representing an ensemble where is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need density matrices to represent the state.<br />
<br />
其中 w < sub > i </sub > 是正值概率(和为1) ,向量是单位向量,在无限维情况下,我们取这些状态的闭包为迹范数。我们可以解释为代表一个集合,其中集合的状态是 < math > | alpha _ i rangle </math > 。当一个混合状态的秩为1时,它就描述了一个纯系综。当量子系统的状态信息少于总量时,我们需要密度矩阵来表示状态。<br />
<br />
The following subsections are for those with a good working knowledge of the formal, mathematical description of [[quantum mechanics]], including familiarity with the formalism and theoretical framework developed in the articles: [[bra–ket notation]] and [[mathematical formulation of quantum mechanics]].<br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits electrons towards an observer. The electrons' Hilbert spaces are identical. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with spins aligned in the positive direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
在实验上,可以实现如下的混合集成。考虑一个“黑盒子”装置,它向观察者喷射电子。电子的希尔伯特空间是相同的。该装置可能产生全部处于相同状态的电子; 在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以在不同的状态下产生电子。例如,它可以产生两个电子群: 一个是状态 < math > | mathbf { z } + rangle </math > 的正方向自旋,另一个是状态 < math > | mathbf { y }-rangle </math > 的负方向自旋。通常,这是一个混合集合,因为可以有任意数量的总体,每个总体对应不同的状态。<br />
<br />
=== Pure states ===<br />
<br />
Consider two arbitrary quantum systems {{mvar|A}} and {{mvar|B}}, with respective [[Hilbert space]]s {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}. The Hilbert space of the composite system is the [[tensor product]]<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on . That is, it has the general form<br />
<br />
根据上面的定义,对于二部复合系统,混合态仅仅是上面的密度矩阵。也就是说,它有一般的形式<br />
<br />
<br />
<br />
: <math> H_A \otimes H_B.</math><br />
<br />
<math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
[数学] rho = sum { i } w _ i 左[ sum _ { j } bar { c }{ ij }(| alpha _ { ij } rangle otimes | beta _ { ij } rangle)右]左[ sum _ k c _ { ik }(langle alpha _ ik } | otimes langle beta _ { ik } | 右]<br />
<br />
<br />
<br />
</math><br />
<br />
数学<br />
<br />
If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
<br />
<br />
<br />
where the w<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
其中 w < sub > i </sub > 是正值概率,< math > sum _ j | c _ { ij } | ^ 2 = 1 </math > ,向量是单位向量。这是自伴和正的,并且有迹1。<br />
<br />
: <math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<br />
<br />
从纯粹情形扩展可分性的定义,我们说混合状态是可分的,如果它可以写成<br />
<br />
States of the composite system that can be represented in this form are called [[separable state]]s, or [[product state]]s.<br />
<br />
<br />
<br />
<math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
(数学) rho = sum i w i rho i ^ a times rho i ^ b,(数学)<br />
<br />
Not all states are separable states (and thus product states). Fix a [[basis (linear algebra)|basis]] <math>\scriptstyle \{|i \rangle_A\}</math> for {{mvar|H<sub>A</sub>}} and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for {{mvar|H<sub>B</sub>}}. The most general state in {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} is of the form<br />
<br />
<br />
<br />
where the are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems and respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
其中的正值概率和 rho _ i ^ a </math > 的和 rho _ i ^ b </math > 的本身是子系统和子系统上的混合状态(密度算符)。换句话说,如果一个状态是不相关状态或乘积状态上的概率分布,则该状态是可分的。通过将密度矩阵写成纯系综和并进行扩展,我们可以假定,不失一般性和数学本身就是纯系综。如果一个状态不可分离,则称其为纠缠态。<br />
<br />
: <math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be NP-hard. For the and cases, a necessary and sufficient criterion for separability is given by the famous Positive Partial Transpose (PPT) condition.<br />
<br />
一般来说,要判断一个混合态是否是纠缠态是很困难的。一般的二部格被证明是 np 困难的。对于和种情形,利用著名的正偏转子(PPT)条件给出了可分性的一个充要条件。<br />
<br />
This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
<br />
<br />
<br />
For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of {{mvar|H<sub>A</sub>}} and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of {{mvar|H<sub>B</sub>}}, the following is an entangled state:<br />
<br />
The idea of a reduced density matrix was introduced by Paul Dirac in 1930. Consider as above systems and each with a Hilbert space . Let the state of the composite system be<br />
<br />
约化密度矩阵的概念是由保罗 · 狄拉克在1930年提出的。考虑以上系统,每个系统都有一个希尔伯特空间。设复合系统的状态为<br />
<br />
<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
<br />
<math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
[数学] | Psi 在 h _ a 和 h _ b 之间。数学<br />
<br />
<br />
<br />
If the composite system is in this state, it is impossible to attribute to either system {{mvar|A}} or system {{mvar|B}} a definite [[pure state]]. Another way to say this is that while the [[von Neumann entropy]] of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry.<ref name="JaegerEtAl95">{{cite journal |author=Jaeger G, Shimony A, Vaidman L |title=Two Interferometric Complementarities |journal=Phys. Rev. |volume=51 |issue=1 |pages=54–67 |year=1995 |doi=10.1103/PhysRevA.51.54|pmid=9911555 |bibcode = 1995PhRvA..51...54J |last2=Shimony |last3=Vaidman }}</ref> The above example is one of four [[Bell states]], which are (maximally) entangled pure states (pure states of the {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} space, but which cannot be separated into pure states of each {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}).<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system . However, it still is possible to associate a density matrix. Let<br />
<br />
如上所述,通常没有办法将纯状态关联到组件系统。然而,仍然有可能将密度矩阵联系起来。让<br />
<br />
<br />
<br />
Now suppose Alice is an observer for system {{mvar|A}}, and Bob is an observer for system {{mvar|B}}. If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of {{mvar|A}}, there are two possible outcomes, occurring with equal probability:<ref name=nielchuang>{{cite book| last = Nielsen | first = Michael A. |author2=Chuang, Isaac L. | year = 2000 | title = Quantum Computation and Quantum Information | publisher = [[Cambridge University Press]] | pages = 112–113| isbn = 978-0-521-63503-5}}</ref><br />
<br />
<math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
我不知道,我不知道,我不知道。<br />
<br />
<br />
<br />
# Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
<br />
which is the projection operator onto this state. The state of is the partial trace of over the basis of system :<br />
<br />
也就是这个状态的投影操作符。状态是系统基础上的部分轨迹:<br />
<br />
# Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
<br />
<br />
<br />
<math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
(| Psi rangle langle Psi | right) | j rangle b = hbox { Tr } _ b; rho _ t. </math > <br />
<br />
If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system {{mvar|B}} has been altered by Alice performing a local measurement on system {{mvar|A}}. This remains true even if the systems {{mvar|A}} and {{mvar|B}} are spatially separated. This is the foundation of the [[EPR paradox]].<br />
<br />
<br />
<br />
is sometimes called the reduced density matrix of on subsystem . Colloquially, we "trace out" system to obtain the reduced density matrix on .<br />
<br />
有时被称为子系统的约化密度矩阵。通俗地说,我们“追踪”系统,以获得约化密度矩阵。<br />
<br />
The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see [[no-communication theorem]].<br />
<br />
<br />
<br />
For example, the reduced density matrix of for the entangled state<br />
<br />
例如,纠缠态的约化密度矩阵<br />
<br />
=== Ensembles ===<br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a [[density matrix]], which is a [[positive-semidefinite matrix]], or a [[trace class]] when the state space is infinite-dimensional, and has trace 1. Again, by the [[spectral theorem]], such a matrix takes the general form:<br />
<br />
<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right) ,</math > <br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
discussed above is<br />
<br />
以上所讨论的是<br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors {{mvar| α<sub>i</sub>}} are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret {{mvar|ρ}} as representing an ensemble where {{mvar|w<sub>i</sub>}} is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need [[#Reduced density matrices|density matrices]] to represent the state.<br />
<br />
<math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
左(| 0 rangle 0 | a + | 1 rangle 1 | a right) </math > <br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits [[electron]]s towards an observer. The electrons' Hilbert spaces are [[identical particles|identical]]. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with [[spin (physics)|spins]] aligned in the positive {{math|'''z'''}} direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative {{math|'''y'''}} direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
这表明,正如预期的那样,一个纠缠纯系综的约化密度矩阵是一个混合系综。同样不足为奇的是,上面讨论的纯乘积态的密度矩阵<br />
<br />
<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}}. That is, it has the general form<br />
<br />
<math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
我不知道,但是我知道,我知道。<br />
<br />
<br />
<br />
: <math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
一般情况下,二体纯态 ρ 纠缠当且仅当其约化态是混合态而不是纯态。<br />
<br />
</math><br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional AKLT spin chain: the ground state can be divided into a block and an environment. The reduced density matrix of the block is proportional to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
在不同的基态自旋链中显式计算了约化密度矩阵。一维 AKLT 自旋链就是一个例子: 基态可以分为一个区块和一个环境。块的约化密度矩阵与另一个哈密顿量的简并基态成正比。<br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<ref name=Laloe>{{citation|last=Laloe|first=Franck|year=2001|title=Do We Really Understand Quantum Mechanics|journal=American Journal of Physics |volume=69 |issue=6|pages=655–701 |arxiv=quant-ph/0209123 |bibcode=2001AmJPh..69..655L |doi=10.1119/1.1356698}}</ref>{{rp|131–132}}<br />
<br />
The reduced density matrix also was evaluated for XY spin chains, where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence in this case.<br />
<br />
并对 XY 自旋链的全秩约化密度矩阵进行了计算。证明了在热力学极限中,大块自旋的约化密度矩阵的谱在这种情况下是一个精确的几何序列。<br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary quantum operations can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called LOCC (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<br />
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在量子信息理论中,纠缠态被认为是一种“资源” ,即制造成本高昂的物质,并且可以实现有价值的转换。这种观点最为明显的背景是“遥远的实验室” ,即两个标记为“ a”和“ b”的量子系统,其中每个系统都可以执行任意的量子操作,但它们之间不存在量子力学相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为 LOCC 的操作(局部操作和经典通信)。这些操作不允许在系统 a 和系统 b 之间产生纠缠态。但是如果给 a 和 b 提供了纠缠态,那么这些纠缠态和 LOCC 操作一起可以产生更大类的变换。例如,a 的一个量子比特和 b 的一个量子比特之间的相互作用可以通过首先将 a 的量子比特传送到 b,然后让 b 的量子比特和 b 的量子比特相互作用(这现在是一个 LOCC 操作,因为两个量子比特都在 b 的实验室里) ,然后再传送量子比特回到 a。两个量子比特的最大纠缠态在这个过程中被用完。因此,纠缠态是一种资源,它能够在只有 LOCC 可用的情况下实现量子相互作用(或量子通道) ,但是在这个过程中会被消耗掉。在其他应用中,纠缠态可以被看作是一种资源,例如,私人通信或者区分量子态。<br />
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where the {{mvar|w<sub>i</sub>}} are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems {{mvar|A}} and {{mvar|B}} respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
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In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be [[NP-hard]].<ref>{{Cite book |author=Gurvits L |title=Proceedings of the thirty-fifth ACM symposium on Theory of computing - STOC '03 |chapter=Classical deterministic complexity of Edmonds' Problem and quantum entanglement |journal=Proceedings of the Thirty-fifth Annual ACM Symposium on Theory of Computing |year=2003 |doi=10.1145/780542.780545 |page=10 |isbn=978-1-58113-674-6|arxiv=quant-ph/0303055 |s2cid=5745067 }}</ref> For the {{math|2 × 2}} and {{math|2 × 3}} cases, a necessary and sufficient criterion for separability is given by the famous [[Peres-Horodecki criterion|Positive Partial Transpose (PPT)]] condition.<ref>{{cite journal |author=Horodecki M, Horodecki P, Horodecki R |title=Separability of mixed states: necessary and sufficient conditions |journal=Physics Letters A |volume=223 |issue=1 |page=210 |year=1996 |doi=10.1016/S0375-9601(96)00706-2 |bibcode=1996PhLA..223....1H|arxiv = quant-ph/9605038 |last2=Horodecki |last3=Horodecki |citeseerx=10.1.1.252.496 |s2cid=10580997 }}</ref><br />
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=== Reduced density matrices ===<br />
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In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
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在这一节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的度量。<br />
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The idea of a reduced density matrix was introduced by [[Paul Dirac]] in 1930.<ref>{{cite journal|doi=10.1017/S0305004100016108|title=Note on Exchange Phenomena in the Thomas Atom|year=2008|last1=Dirac|first1=P. A. M.|journal=Mathematical Proceedings of the Cambridge Philosophical Society| volume=26| issue=3|page=376|bibcode=1930PCPS...26..376D|url=https://www.cambridge.org/core/services/aop-cambridge-core/content/view/6C5FF7297CD96F49A8B8E9E3EA50E412/S0305004100016108a.pdf/div-class-title-note-on-exchange-phenomena-in-the-thomas-atom-div.pdf}}</ref> Consider as above systems {{mvar|A}} and {{mvar|B}} each with a Hilbert space {{mvar|H<sub>A</sub>, H<sub>B</sub>}}. Let the state of the composite system be<br />
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: <math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
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The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.<br />
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二分子2能级纯态的冯纽曼熵与本征值的图。当本征值为5时,冯纽曼熵处于最大值,相当于最大纠缠度。<br />
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In classical information theory , the Shannon entropy, is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<br />
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在经典的信息论中,香农熵,是与概率分布相关联的,如下:<br />
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As indicated above, in general there is no way to associate a pure state to the component system {{mvar|A}}. However, it still is possible to associate a density matrix. Let<br />
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<math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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[ math ] h (p _ 1,cdots,p _ n) =-sum _ i p _ i log _ 2 p _ i. [ math ]<br />
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: <math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
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Since a mixed state is a probability distribution over an ensemble, this leads naturally to the definition of the von Neumann entropy:<br />
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由于混合状态是一个概率分布超过一个总体,这自然导致了冯纽曼熵的定义:<br />
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which is the [[projection operator]] onto this state. The state of {{mvar|A}} is the [[partial trace]] of {{mvar|ρ<sub>T</sub>}} over the basis of system {{mvar|B}}:<br />
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<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
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(rho) =-hbox { Tr } left (rho log _ 2{ rho } right) <br />
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: <math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
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In general, one uses the Borel functional calculus to calculate a non-polynomial function such as . If the nonnegative operator acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
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一般来说,人们使用 Borel 函数演算来计算一个非多项式函数,如。如果非负算子作用于有限维希尔伯特空间,并且具有本征值 < math > lambda _ 1,那么 cdots,lambda _ n </math > ,结果只不过是具有相同本征向量的算子,但本征值 < math > log _ 2(lambda _ 1) ,点,log _ 2(lambda _ n) </math > 。那么香农熵就是:<br />
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{{mvar|ρ<sub>A</sub>}} is sometimes called the reduced density matrix of {{mvar|ρ}} on subsystem {{mvar|A}}. Colloquially, we "trace out" system {{mvar|B}} to obtain the reduced density matrix on {{mvar|A}}.<br />
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<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
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(rho) =-hbox { Tr } left (rho log 2{ rho } right) =-sum _ i lambda _ i log _ 2 lambda _ i </math > .<br />
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For example, the reduced density matrix of {{mvar|A}} for the entangled state<br />
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Since an event of probability 0 should not contribute to the entropy, and given that<br />
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因为一个概率为0的事件不应该对熵有贡献,并且假设<br />
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: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
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<math> \lim_{p \to 0} p \log p = 0,</math><br />
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[ math > lim _ { p to 0} p log p = 0,</math > <br />
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discussed above is<br />
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the convention 0}} is adopted. This extends to the infinite-dimensional case as well: if has spectral resolution<br />
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约定0}被采用。这也延伸到无限维情况: 如果有光谱分辨率<br />
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: <math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
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<math> \rho = \int \lambda d P_{\lambda},</math><br />
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数学,数学,数学<br />
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This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of {{mvar|A}} for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
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assume the same convention when calculating<br />
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在计算时采用相同的约定<br />
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: <math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
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<math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
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[数学] rho log 2 rho = int lambda log 2 lambda d { lambda }<br />
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In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
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As in statistical mechanics, the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is (which can be shown to be the maximum entropy for mixed states).<br />
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就像统计力学一样,系统的不确定性(微观状态的数量)越多,熵就越大。例如,任何纯态的熵都为零,这并不奇怪,因为处于纯态的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个的熵都是(混合态的最大熵)。<br />
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=== Two applications that use them ===<br />
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Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional [[AKLT Model|AKLT spin chain]]:<ref name="Fan2004">{{cite journal | doi = 10.1103/PhysRevLett.93.227203 | title = Entanglement in a Valence-Bond Solid State | journal = Physical Review Letters | year = 2004 | first = H | last = Fan | page = 227203 |author2=Korepin V |author3=Roychowdhury V | volume = 93 | issue = 22 | pmid = 15601113 |arxiv=quant-ph/0406067 | bibcode=2004PhRvL..93v7203F| s2cid = 28587190 }}</ref> the ground state can be divided into a block and an environment. The reduced density matrix of the block is [[Proportionality (mathematics)|proportional]] to a projector to a degenerate ground state of another Hamiltonian.<br />
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Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist. If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
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熵提供了一个可以用来量化纠缠的工具,尽管还存在其他的纠缠度量方法。如果整个系统是纯系统,则可以用一个子系统的熵来衡量其与其他子系统的纠缠程度。<br />
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The reduced density matrix also was evaluated for [[Heisenberg model (quantum)|XY spin chains]], where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence<ref>{{cite journal| doi=10.1007/s11128-010-0197-7|arxiv=1002.2931|title=Spectrum of the density matrix of a large ''block of'' spins of the XY model in one dimension| year=2010|last1=Franchini|first1=F.|last2=Its|first2=A. R.|last3=Korepin|first3=V. E.|last4=Takhtajan|first4=L. A.|journal=Quantum Information Processing|volume=10|issue=3|pages=325–341|s2cid=6683370}}</ref> in this case.<br />
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For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
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对于两体纯态,减少态的冯纽曼熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的特定公理的态家族中唯一的函数。<br />
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=== Entanglement as a resource ===<br />
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In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary [[quantum operation]]s can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called [[LOCC]] (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<ref name="horodecki2007" /><br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/n,...,1/n}. Therefore, a bipartite pure state is said to be a maximally entangled state if the reduced state of is the diagonal matrix<br />
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一个经典的结果是,香农熵在均匀概率分布{1/n,... ,1/n }处达到最大值。因此,如果二分纯态的约化态是对角矩阵,则称二分纯态为最大纠缠态<br />
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=== Classification of entanglement ===<br />
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<math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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< math > begin { bmatrix } frac {1}{ n } & & ddots & frac {1}{ n } end { bmatrix } . </math > <br />
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Not all quantum states are equally valuable as a resource. To quantify this value, different [[Quantum entanglement#Entanglement measures|entanglement measures]] (see below) can be used, that assign a numerical value to each quantum state. However, it is often interesting to settle for a coarser way to compare quantum states. This gives rise to different classification schemes. Most entanglement classes are defined based on whether states can be converted to other states using LOCC or a subclass of these operations. The smaller the set of allowed operations, the finer the classification. Important examples are:<br />
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* If two states can be transformed into each other by a local unitary operation, they are said to be in the same ''LU class''. This is the finest of the usually considered classes. Two states in the same LU class have the same value for entanglement measures and the same value as a resource in the distant-labs setting. There is an infinite number of different LU classes (even in the simplest case of two qubits in a pure state).<ref name="GRB1998">>{{cite journal |author1=Grassl, M. |author2=Rötteler, M. |author3=Beth, T. |title=Computing local invariants of quantum-bit systems |journal=Phys. Rev. A |volume=58 |issue=3 |pages=1833–1839 |year=1998 |doi=10.1103/PhysRevA.58.1833 |arxiv=quant-ph/9712040|bibcode=1998PhRvA..58.1833G |s2cid=15892529 }}</ref><ref name="Kraus2010">{{cite journal |author=B. Kraus |authorlink=Barbara Kraus|title=Local unitary equivalence of multipartite pure states |journal=Phys. Rev. Lett. |volume=104 |issue=2 |page=020504 |year=2010 |arxiv=0909.5152 |doi=10.1103/PhysRevLett.104.020504|pmid=20366579 |bibcode=2010PhRvL.104b0504K|s2cid=29984499}}</ref><br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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对于混合态,简化冯纽曼熵并不是唯一合理的纠缠度量。<br />
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* If two states can be transformed into each other by local operations including measurements with probability larger than 0, they are said to be in the same 'SLOCC class' ("stochastic LOCC"). Qualitatively, two states <math>\rho_1</math> and <math>\rho_2</math> in the same SLOCC class are equally powerful (since I can transform one into the other and then do whatever it allows me to do), but since the transformations <math>\rho_1\to\rho_2</math> and <math>\rho_2\to\rho_1</math> may succeed with different probability, they are no longer equally valuable. E.g., for two pure qubits there are only two SLOCC classes: the entangled states (which contains both the (maximally entangled) Bell states and weakly entangled states like <math>|00\rangle+0.01|11\rangle</math>) and the separable ones (i.e., product states like <math>|00\rangle</math>).<ref>{{cite journal |author=M. A. Nielsen |title=Conditions for a Class of Entanglement Transformations |journal=Phys. Rev. Lett. |volume=83 |issue=2 |page=436 |year=1999 |doi=10.1103/PhysRevLett.83.436 |arxiv=quant-ph/9811053|bibcode=1999PhRvL..83..436N |s2cid=17928003 }}</ref><ref name="GoWa2010">{{cite journal |authors=Gour, G. & Wallach, N. R. |title=Classification of Multipartite Entanglement of All Finite Dimensionality |journal=Phys. Rev. Lett. |volume=111 |issue=6 |page=060502 |year=2013 |doi=10.1103/PhysRevLett.111.060502 |pmid=23971544 |arxiv=1304.7259|bibcode=2013PhRvL.111f0502G |s2cid=1570745 }}</ref><br />
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* Instead of considering transformations of single copies of a state (like <math>\rho_1\to\rho_2</math>) one can define classes based on the possibility of multi-copy transformations. E.g., there are examples when <math>\rho_1\to\rho_2</math> is impossible by LOCC, but <math>\rho_1\otimes\rho_1\to\rho_2</math> is possible. A very important (and very coarse) classification is based on the property whether it is possible to transform an arbitrarily large number of copies of a state <math>\rho</math> into at least one pure entangled state. States that have this property are called [[Entanglement distillation|distillable]]. These states are the most useful quantum states since, given enough of them, they can be transformed (with local operations) into any entangled state and hence allow for all possible uses. It came initially as a surprise that not all entangled states are distillable, those that are not are called '[[Bound entanglement|bound entangled]]'.<ref name="HHH97">{{cite journal |author1=Horodecki, M. |author2=Horodecki, P. |author3=Horodecki, R. |title=Mixed-state entanglement and distillation: Is there a ''bound'' entanglement in nature? |journal=Phys. Rev. Lett. |volume=80 |issue=1998 |pages=5239–5242 |year=1998 |arxiv=quant-ph/9801069|doi=10.1103/PhysRevLett.80.5239 |bibcode=1998PhRvL..80.5239H |s2cid=111379972 }}</ref><ref name="horodecki2007" /><br />
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As an aside, the information-theoretic definition is closely related to entropy in the sense of statistical mechanics (comparing the two definitions in the present context, it is customary to set the Boltzmann constant 1}}). For example, by properties of the Borel functional calculus, we see that for any unitary operator ,<br />
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顺便说一句,信息论的定义与统计力学意义上的熵密切相关(比较在当前语境下的两个定义,通常设置波兹曼常数1})。例如,通过 Borel 泛函微积分的性质,我们可以看到,对于任何幺正算符,<br />
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A different entanglement classification is based on what the quantum correlations present in a state allow A and B to do: one distinguishes three subsets of entangled states: (1) the ''[[Quantum nonlocality|non-local]] states'', which produce correlations that cannot be explained by a local hidden variable model and thus violate a Bell inequality, (2) the ''[[Quantum steering|steerable]] states'' that contain sufficient correlations for A to modify ("steer") by local measurements the conditional reduced state of B in such a way, that A can prove to B that the state they possess is indeed entangled, and finally (3) those entangled states that are neither non-local nor steerable. All three sets are non-empty.<ref name="WJD2007">{{cite journal |title=Steering, Entanglement, Nonlocality, and the Einstein-Podolsky-Rosen Paradox |authors=H. M. Wiseman, S. J. Jones, and A. C. Doherty |journal=Phys. Rev. Lett. |volume=98 |issue=14 |page=140402 |year=2007 |doi=10.1103/PhysRevLett.98.140402 |pmid=17501251 |arxiv=quant-ph/0612147|bibcode=2007PhRvL..98n0402W |s2cid=30078867 }}</ref><br />
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<math>S(\rho) = S \left (U \rho U^* \right).</math><br />
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s (rho) = s left (u rho u ^ * right) . </math > <br />
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=== Entropy ===<br />
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Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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事实上,如果没有这个属性,冯纽曼熵就不会有明确的定义。<br />
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In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
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In particular, could be the time evolution operator of the system, i.e.,<br />
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特别是,可以是系统的时间演化算子,即,<br />
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==== Definition ====<br />
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[[File:Von Neumann entropy for bipartite system plot.svg|right|thumb|200px|The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.]]<br />
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<math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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[ math ] u (t) = exp left (frac {-i h t }{ hbar } right) ,[ math ]<br />
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In classical [[information theory]] {{mvar|H}}, the [[Shannon entropy]], is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<ref name="SE">{{cite web |url=http://authors.library.caltech.edu/5516/1/CERpra97b.pdf#page=10 |title=Information-theoretic interpretation of quantum error-correcting codes |first1=Nicolas J. |last1=Cerf |first2=Richard |last2=Cleve }}</ref><br />
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where is the Hamiltonian of the system. Here the entropy is unchanged.<br />
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这个系统的哈密顿量在哪里。这里熵不变。<br />
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: <math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the arrow of time towards thermodynamic equilibrium is simply the growing spread of quantum entanglement.<br />
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一个过程的可逆性与由此产生的熵变有关,也就是说,一个过程是可逆的,当且仅当它使系统的熵不变。因此,时间之箭向热力学平衡的前进只不过是量子纠缠的蔓延。<br />
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Since a mixed state {{mvar|ρ}} is a probability distribution over an ensemble, this leads naturally to the definition of the [[von Neumann entropy]]:<br />
<br />
This provides a connection between quantum information theory and thermodynamics.<br />
<br />
这提供了量子信息理论和热力学之间的联系。<br />
<br />
<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
<br />
Rényi entropy also can be used as a measure of entanglement.<br />
<br />
熵也可以用来度量纠缠。<br />
<br />
<br />
<br />
In general, one uses the [[Borel functional calculus]] to calculate a non-polynomial function such as {{math|log<sub>2</sub>(''ρ'')}}. If the nonnegative operator {{mvar|ρ}} acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, {{math|log<sub>2</sub>(''ρ'')}} turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
<br />
<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, entanglement entropy is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<br />
<br />
量子纠缠度量了量子态(通常被视为双体)中纠缠的数量。如前所述,纠缠熵是纯态的标准量度(但不再是混合态的量度)。对于混合态,文献中有一些纠缠度量<br />
<br />
: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
<br />
<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
<br />
The Reeh-Schlieder theorem of quantum field theory is sometimes seen as an analogue of quantum entanglement.<br />
<br />
量子场论的 Reeh-Schlieder 定理有时被看作是量子纠缠的类比。<br />
<br />
<br />
<br />
:<math> \lim_{p \to 0} p \log p = 0,</math><br />
<br />
<br />
<br />
the convention {{math|0 log(0) {{=}} 0}} is adopted. This extends to the infinite-dimensional case as well: if {{mvar|ρ}} has [[projection-valued measure|spectral resolution]]<br />
<br />
Entanglement has many applications in quantum information theory. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
<br />
纠缠态在量子信息理论中有许多应用。在纠缠的帮助下,否则不可能完成的任务就可能实现。<br />
<br />
<br />
<br />
: <math> \rho = \int \lambda d P_{\lambda},</math><br />
<br />
Among the best-known applications of entanglement are superdense coding and quantum teleportation.<br />
<br />
其中最著名的应用是超稠密编码和量子遥传纠缠。<br />
<br />
<br />
<br />
assume the same convention when calculating<br />
<br />
Most researchers believe that entanglement is necessary to realize quantum computing (although this is disputed by some).<br />
<br />
大多数研究人员认为量子纠缠对于实现量子计算是必要的(尽管有些人对此有争议)。<br />
<br />
<br />
<br />
: <math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
<br />
Entanglement is used in some protocols of quantum cryptography. This is because the "shared noise" of entanglement makes for an excellent one-time pad. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.<br />
<br />
纠缠被用于量子密码学的一些协议中。这是因为纠缠的“共享噪音”造就了绝佳的一次性衬垫。此外,由于测量纠缠对的任何一个成员都会破坏它们共享的纠缠,基于纠缠的量子密码学可以让发送方和接收方更容易地检测到拦截器的存在。<br />
<br />
<br />
<br />
As in [[entropy|statistical mechanics]], the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is {{math|log(2)}} (which can be shown to be the maximum entropy for {{math|2 × 2}} mixed states).<br />
<br />
In interferometry, entanglement is necessary for surpassing the standard quantum limit and achieving the Heisenberg limit.<br />
<br />
在干涉术中,纠缠态对于超越标准量子极限和达到海森堡极限是必要的。<br />
<br />
<br />
<br />
==== As a measure of entanglement ====<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist.<ref name="arxiv.org">{{cite journal|author1=Plenio|title=An introduction to entanglement measures|year=2007|pages=1–51|volume=1|journal=Quant. Inf. Comp. |arxiv=quant-ph/0504163|bibcode=2005quant.ph..4163P|last2=Virmani}}</ref> If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
<br />
在理论和实验中经常会出现几种典型的纠缠态。<br />
<br />
<br />
<br />
For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
<br />
For two qubits, the Bell states are<br />
<br />
对于两个量子比特,贝尔态是<br />
<br />
<br />
<br />
It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/''n'',...,1/''n''}. Therefore, a bipartite pure state {{math|''ρ'' ∈ ''H''<sub>A</sub> ⊗ ''H''<sub>B</sub>}} is said to be a '''maximally entangled state''' if the reduced state{{clarify|reason=To which system, A or B, or perhaps both?|date=May 2015}} of {{mvar|ρ}} is the diagonal matrix<br />
<br />
<math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
<br />
< math > | Phi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 0 rangle _ b | 1 rangle _ a o times | 1 rangle _ b) </math > <br />
<br />
<br />
<br />
<math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
<br />
< math > | Psi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 1 rangle _ b pm | 1 rangle _ a o times | 0 rangle _ b) </math > .<br />
<br />
: <math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
<br />
<br />
<br />
These four pure states are all maximally entangled (according to the entropy of entanglement) and form an orthonormal basis (linear algebra) of the Hilbert space of the two qubits. They play a fundamental role in Bell's theorem.<br />
<br />
这四个纯态都是最大纠缠态(根据纠缠熵) ,并且形成了两个量子位的希尔伯特空间的标准正交基(线性代数)。它们在贝尔定理中起着基本的作用。<br />
<br />
For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
<br />
<br />
<br />
For M>2 qubits, the GHZ state is<br />
<br />
对于 m > 2量子位,GHZ 态是<br />
<br />
As an aside, the information-theoretic definition is closely related to [[entropy (statistical views)|entropy]] in the sense of statistical mechanics{{Citation needed|date=January 2009}} (comparing the two definitions in the present context, it is customary to set the [[Boltzmann constant]] {{math|''k'' {{=}} 1}}). For example, by properties of the [[Borel functional calculus]], we see that for any [[unitary operator]] {{mvar|U}},<br />
<br />
<br />
<br />
<math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
<br />
< math > | mathrm { GHZ } rangle = frac { | 0 rangle ^ { otimes m } + | 1 rangle ^ { otimes m }{ sqrt {2} ,</math > <br />
<br />
: <math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
<br />
<br />
which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to qudits, i.e., systems of d rather than 2 dimensions.<br />
<br />
它缩小到贝尔状态。传统的 GHZ 状态定义为 < math > m = 3 </math > 。GHZ 状态偶尔会扩展到 qudit,即 d 而不是2维系统。<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
<br />
<br />
<br />
Also for M>2 qubits, there are spin squeezed states. Spin squeezed states are a class of squeezed coherent states satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled. Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<br />
<br />
对于 m > 2量子位,也存在自旋压缩态。自旋压缩态是一类对自旋测量不确定度满足一定限制的压缩相干态,它必然是纠缠态。自旋压缩态是利用量子纠缠增强精密测量的理想候选态。<br />
<br />
In particular, {{mvar|U}} could be the time evolution operator of the system, i.e.,<br />
<br />
<br />
<br />
For two bosonic modes, a NOON state is<br />
<br />
对于两个玻色模态,NOON 状态是<br />
<br />
: <math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
<br />
<br />
<br />
<math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
<br />
[数学] | psi _ text { NOON } rangle = frac { | n rangle _ a | 0 rangle _ b + | {0} rangle _ a | { n } rangle _ b }{ sqrt {2} ,,</math > <br />
<br />
where {{mvar|H}} is the [[Hamiltonian (quantum mechanics)|Hamiltonian]] of the system. Here the entropy is unchanged.<br />
<br />
<br />
<br />
This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the N photons are in one mode" and "the N photons are in the other mode".<br />
<br />
这就像贝尔态 < math > | Psi ^ + rangle </math > 除了基函数0和1已经被“ n 个光子处于一种模式”和“ n 个光子处于另一种模式”所取代。<br />
<br />
The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the [[arrow of time]] towards [[thermodynamic equilibrium]] is simply the growing spread of quantum entanglement.<ref>{{cite news |url=https://www.wired.com/2014/04/quantum-theory-flow-time/ |title=New Quantum Theory Could Explain the Flow of Time |last1=Wolchover |first1=Natalie |date=25 April 2014 |website=www.wired.com |publisher=Quanta Magazine |accessdate=27 April 2014}}</ref><br />
<br />
This provides a connection between [[quantum information theory]] and [[thermodynamics]].<br />
<br />
Finally, there also exist twin Fock states for bosonic modes, which can be created by feeding a Fock state into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<br />
<br />
最后,还存在玻色子模式的双 Fock 态,它可以通过将 Fock 态输入到两个导致分束器的臂来产生。它们是 NOON 态的倍数之和,可以用来实现海森堡极限。<br />
<br />
<br />
<br />
[[Rényi entropy]] also can be used as a measure of entanglement.<br />
<br />
For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
<br />
对于适当选择的纠缠度量,Bell、 GHZ 和 NOON 态是最大纠缠态,而自旋压缩态和双 Fock 态只是部分纠缠。部分纠缠态通常更容易在实验上准备。<br />
<br />
<br />
<br />
=== Entanglement measures ===<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, [[entropy of entanglement|entanglement entropy]] is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<ref name="arxiv.org" /> and no single one is standard.<br />
<br />
Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is spontaneous parametric down-conversion to generate a pair of photons entangled in polarisation. Other methods include the use of a fiber coupler to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a quantum dot, the use of the Hong–Ou–Mandel effect, etc., In the earliest tests of Bell's theorem, the entangled particles were generated using atomic cascades.<br />
<br />
纠缠通常是由亚原子粒子间的直接相互作用产生的。这些相互作用可以有多种形式。最常用的方法之一是用自发参量下转换产生一对纠缠在偏振中的光子。其他方法包括使用光纤耦合器来限制和混合光子,量子点中双激子衰变级联发射的光子,Hong-Ou-Mandel 效应的使用等等。在贝尔定理最早的测试中,纠缠粒子是利用原子级联产生的。<br />
<br />
* Entanglement cost<br />
<br />
* [[entanglement distillation|Distillable entanglement]]<br />
<br />
It is also possible to create entanglement between quantum systems that never directly interacted, through the use of entanglement swapping. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<br />
<br />
通过使用纠缠交换,也有可能在不直接相互作用的量子系统之间创造纠缠。如果它们的波函数在空间上仅仅重叠,至少是部分重叠,那么它们也可以相互纠缠全同粒子。<br />
<br />
* Entanglement of formation<br />
<br />
* [[quantum relative entropy|Relative entropy of entanglement]]<br />
<br />
* [[Squashed entanglement]]<br />
<br />
* [[Logarithmic negativity]]<br />
<br />
A density matrix ρ is called separable if it can be written as a convex sum of product states, namely<br />
<br />
密度矩阵 ρ 称为可分的,如果它可以写成乘积态的凸和,即<br />
<br />
Most (but not all) of these entanglement measures reduce for pure states to entanglement entropy, and are difficult ([[NP-hard]]) to compute.<ref>{{cite journal|last1=Huang|first1=Yichen|title=Computing quantum discord is NP-complete|journal=New Journal of Physics|date=21 March 2014|volume=16|issue=3|pages=033027|doi=10.1088/1367-2630/16/3/033027|bibcode=2014NJPh...16c3027H|arxiv = 1305.5941 |s2cid=118556793}}</ref><br />
<br />
<br />
<br />
<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
<br />
显示方式{ rho = sum _ j p _ j rho _ j ^ {(a)}次 rho _ j ^ {(b)}} </math > <br />
<br />
=== Quantum field theory ===<br />
<br />
The [[Reeh-Schlieder theorem]] of [[quantum field theory]] is sometimes seen as an analogue of quantum entanglement.<br />
<br />
with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
<br />
概率为1 ge p _ j ge 0 </math > 。根据定义,如果一个态不可分离,它就是纠缠态。<br />
<br />
<br />
<br />
== Applications ==<br />
<br />
For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple Peres–Horodecki criterion provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes NP-hard when generalized. Other separability criteria include (but not limited to) the range criterion, reduction criterion, and those based on uncertainty relations. See Ref. for a review of separability criteria in discrete variable systems.<br />
<br />
对于2量子比特和2 × 2量子比特-量子特里特系统(分别为2 × 2和2 × 3) ,简单的 Peres-horowitz 准则为分离提供了一个必要和充分的判据,从而无意识地提供了检测纠缠的判据。然而,对于一般情形,该判据仅仅是可分性的必要条件,因为问题一经推广就变成了 np 难问题。其他可分性标准包括(但不限于)范围标准、归约标准和基于不确定关系的标准。参见参考文献。回顾了离散变量系统的可分性准则。<br />
<br />
<br />
<br />
Entanglement has many applications in [[quantum information theory]]. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
<br />
A numerical approach to the problem is suggested by Jon Magne Leinaas, Jan Myrheim and Eirik Ovrum in their paper "Geometrical aspects of entanglement". Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in Peres-Horodecki criterion testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
<br />
Jon Magne Leinaas,Jan Myrheim 和 Eirik Ovrum 在他们的论文“纠缠的几何方面”中提出了一个数值方法来解决这个问题。莱纳斯等。提供一个数值方法,迭代精炼一个估计的可分离状态朝向要测试的目标状态,并检查目标状态是否确实能够到达。该算法的一个实现(包括内置的 peres-horowitz 标准测试)是[ StateSeparator http://phweb.technion.ac.il/~StateSeparator/] web-app。<br />
<br />
<br />
<br />
Among the best-known applications of entanglement are [[superdense coding]] and [[quantum teleportation]].<ref>{{cite journal |last1=Bouwmeester |first1=Dik |last2=Pan |first2=Jian-Wei|last3=Mattle |first3=Klaus|last4=Eibl |first4=Manfred |last5=Weinfurter |first5=Harald|last6=Zeilinger |first6=Anton|year=1997 |title=Experimental Quantum Teleportation |journal=Nature |volume=390 |issue=6660 |pages=575–579 |name-list-style=amp |url=http://qudev.ethz.ch/content/courses/QSIT06/pdfs/Bouwmeester97.pdf |doi=10.1038/37539|bibcode = 1997Natur.390..575B |arxiv=1901.11004 |s2cid=4422887 }}</ref><br />
<br />
In continuous variable systems, the Peres-Horodecki criterion also applies. Specifically, Simon formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref. for a seemingly different but essentially equivalent approach). It was later found that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators or by using entropic measures.<br />
<br />
在连续变量系统中,Peres-Horodecki 准则也适用。具体地说,Simon 根据正则算符的二阶矩,制定了 Peres-Horodecki 准则的一个特定版本,并表明它对于 < math > 1 oplus1 </math >-mode Gaussian 状态是必要的和充分的。看似不同,但本质上等价的方法)。后来发现,Simon 的条件对于 < math > 1 oplus n </math >-mode Gaussian 状态也是必要和充分的,但是对于 < math > 2 oplus2 </math >-mode Gaussian 状态不再是充分的。Simon 条件可以通过考虑正则算子的高阶矩或者用熵测度来推广。<br />
<br />
<br />
<br />
Most researchers believe that entanglement is necessary to realize [[quantum computer|quantum computing]] (although this is disputed by some).<ref name="jozsa02">{{cite journal|author1=Richard Jozsa|author2=Noah Linden|doi=10.1098/rspa.2002.1097|title=On the role of entanglement in quantum computational speed-up|year=2002|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=459|issue=2036|pages=2011–2032|arxiv=quant-ph/0201143|bibcode = 2003RSPSA.459.2011J |citeseerx=10.1.1.251.7637|s2cid=15470259}}</ref><br />
<br />
In 2016 China launched the world’s first quantum communications satellite. The $100m Quantum Experiments at Space Scale (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
<br />
2016年,中国发射了世界上第一颗量子通信卫星。耗资1亿美元的空间量子实验任务于2016年8月16日当地时间01:40从中国北方的酒泉卫星发射中心空间站发射升空。<br />
<br />
<br />
<br />
Entanglement is used in some protocols of [[quantum cryptography]].<ref name="ekert91">{{cite journal |doi=10.1103/PhysRevLett.67.661 |title=Quantum cryptography based on Bell's theorem |year=1991 |last1=Ekert |first1=Artur K. |journal=Physical Review Letters |volume=67 |issue=6 |pages=661–663 |pmid=10044956|bibcode = 1991PhRvL..67..661E |s2cid=27683254 |url=http://pdfs.semanticscholar.org/f8dc/c3047eef8da135bca13b926b1e6cf50e7f3a.pdf }}</ref><ref name="horodecki10">{{cite arXiv |eprint=1006.0468|last1=Yin|first1=Juan|title=Contextuality offers device-independent security|last2=Cao|first2=Yuan|last3=Yong|first3=Hai-Lin|last4=Ren|first4=Ji-Gang|last5=Liang|first5=Hao|last6=Liao|first6=Sheng-Kai|last7=Zhou|first7=Fei|last8=Liu|first8=Chang|last9=Wu|first9=Yu-Ping|last10=Pan|first10=Ge-Sheng|last11=Zhang|first11=Qiang|last12=Peng|first12=Cheng-Zhi|last13=Pan|first13=Jian-Wei|class=quant-ph|year=2010}}</ref> This is because the "shared noise" of entanglement makes for an excellent [[one-time pad]]. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.{{citation needed|date=January 2018}}<br />
<br />
For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
<br />
在接下来的两年里,这艘以中国古代哲学家墨子命名的飞船将展示量子化的可行性<br />
<br />
<br />
<br />
communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
<br />
地球和太空之间的通信,并在前所未有的距离上测试量子纠缠。<br />
<br />
In [[interferometry]], entanglement is necessary for surpassing the [[standard quantum limit]] and achieving the [[Heisenberg limit]].<ref>{{cite journal |last1=Pezze |first1=Luca |last2=Smerzi |first2=Augusto|year=2009 |title=Entanglement, Nonlinear Dynamics, and the Heisenberg Limit |journal=Phys. Rev. Lett. |volume=102 |issue=10 |pages=100401 |name-list-style=amp |doi=10.1103/PhysRevLett.102.100401 |pmid=19392092 |bibcode=2009PhRvL.102j0401P|arxiv = 0711.4840 |s2cid=13095638 }}</ref><br />
<br />
<br />
<br />
In the June 16, 2017, issue of Science, Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<br />
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在2017年6月16日的《科学》杂志上。在严格的爱因斯坦定域条件下,从墨丘利卫星到 Lijian、云南和 Delingha、 Quinhai 的基地的 CHSH 估值为2.37 ± 0.09,证明了双光子对的存在和对 Bell 不等式的违反,从而提高了数量级通过光纤实验的传输效率。<br />
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=== Entangled states ===<br />
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There are several canonical entangled states that appear often in theory and experiments.<br />
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For two [[qubits]], the [[Bell state]]s are<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be calculated only by consideration of electron entanglement.<br />
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多电子原子的电子壳层总是由纠缠电子组成。只有考虑到电子纠缠,才能计算出正确的电离能。<br />
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: <math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
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: <math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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It has been suggested that in the process of photosynthesis, entanglement is involved in the transfer of energy between light-harvesting complexes and photosynthetic reaction centers where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using femtosecond spectroscopy, the coherence of entanglement in the Fenna-Matthews-Olson complex was measured over hundreds of femtoseconds (a relatively long time in this regard) providing support to this theory.<br />
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研究表明,在光合作用过程中,纠缠参与了捕光复合物与光合反应中心之间的能量传递,而光(能)是以化学能的形式获得的。没有这样一个过程,光转化为化学能的有效性就无从解释。利用飞秒光谱技术,我们测量了 Fenna-Matthews-Olson 复合体中纠缠态的相干性,时间长达数百飞秒,为这一理论提供了支持。<br />
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These four pure states are all maximally entangled (according to the [[entropy of entanglement]]) and form an [[orthonormal]] [[basis (linear algebra)]] of the Hilbert space of the two qubits. They play a fundamental role in [[Bell's theorem]].<br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<br />
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然而,关键的后续研究对这些结果的解释提出了质疑,并将报告的电子量子相干特征赋予了发色团中的核动力学。<br />
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For M>2 qubits, the [[Greenberger–Horne–Zeilinger state|GHZ state]] is<br />
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In 2020 researchers reported the quantum entanglement between the motion of a millimetre-sized mechanical oscillator and a disparate distant spin system of a cloud of atoms.<br />
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2020年,研究人员报告了一个毫米大小的机械振荡器的运动和一个原子云的不同距离的自旋系统之间的量子纠缠。<br />
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: <math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
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which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to [[qudit]]s, i.e., systems of ''d'' rather than 2 dimensions.<br />
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In October 2018, physicists reported producing quantum entanglement using living organisms, particularly between photosynthetic molecules within living bacteria and quantized light.<br />
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2018年10月,物理学家报告说,他们利用活体生物制造量子纠缠,特别是利用活体细菌中的光合分子和量子化的光。<br />
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Also for M>2 qubits, there are [[Spin squeezing|spin squeezed states]].<ref>[http://qwiki.stanford.edu/index.php/Spin_Squeezed_State Database error – Qwiki] {{webarchive|url=https://web.archive.org/web/20120821011018/http://qwiki.stanford.edu/index.php/Spin_Squeezed_State |date=21 August 2012 }}</ref> Spin squeezed states are a class of [[squeezed coherent states]] satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled.<ref>{{cite journal | last1 = Kitagawa | first1 = Masahiro | last2 = Ueda | first2 = Masahito | year = 1993 | title = Squeezed Spin States | journal = Phys. Rev. A | volume = 47 | issue = 6| pages = 5138–5143 | doi=10.1103/physreva.47.5138| pmid = 9909547 |bibcode = 1993PhRvA..47.5138K }}</ref> Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<ref>{{cite journal | last1 = Wineland | first1 = D. J. | last2 = Bollinger | first2 = J. J. | last3 = Itano | first3 = W. M. | last4 = Moore | first4 = F. L. | last5 = Heinzen | first5 = D. J. | year = 1992| title = Spin squeezing and reduced quantum noise in spectroscopy | url = | journal = Phys. Rev. A | volume = 46| issue = 11| pages = R6797–R6800| doi = 10.1103/PhysRevA.46.R6797 | pmid = 9908086 |bibcode = 1992PhRvA..46.6797W }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<br />
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生物体(绿色硫细菌)已被研究作为介质,在非相互作用的光模式之间创造量子纠缠,表明光和细菌模式之间的高度纠缠,甚至在某种程度上纠缠在细菌内部。<br />
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For two [[boson]]ic modes, a [[NOON state]] is<br />
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: <math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the ''N'' photons are in one mode" and "the ''N'' photons are in the other mode".<br />
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Finally, there also exist [[twin Fock states]] for bosonic modes, which can be created by feeding a [[Fock state]] into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.71.1355|pmid = 10055519|title = Interferometric detection of optical phase shifts at the Heisenberg limit|journal = Physical Review Letters|volume = 71|issue = 9|pages = 1355–1358|year = 1993|last1 = Holland|first1 = M. J|last2 = Burnett|first2 = K|bibcode = 1993PhRvL..71.1355H}}</ref><br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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=== Methods of creating entanglement ===<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is [[spontaneous parametric down-conversion]] to generate a pair of photons entangled in polarisation.<ref name="horodecki2007">{{cite journal |author=Horodecki R, Horodecki P, Horodecki M, Horodecki K |title=Quantum entanglement |journal=Rev. Mod. Phys. |arxiv=quant-ph/0702225 |doi =10.1103/RevModPhys.81.865 |year=2009|pages=865–942 |bibcode=2009RvMP...81..865H |volume=81 |issue=2|last2=Horodecki |last3=Horodecki |last4=Horodecki |s2cid=59577352 }}</ref> Other methods include the use of a [[fiber coupler]] to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a [[quantum dot]],<ref>{{Cite journal|last=Akopian|first=N.|date=2006|title=Entangled Photon Pairs from Semiconductor Quantum Dots|journal=Phys. Rev. Lett.|volume=96|issue=2|pages=130501|arxiv=quant-ph/0509060|bibcode=2006PhRvL..96b0501D|doi=10.1103/PhysRevLett.96.020501|pmid=16486553|s2cid=22040546}}</ref> the use of the [[Hong–Ou–Mandel effect]], etc., In the earliest tests of Bell's theorem, the entangled particles were generated using [[atomic cascade]]s.<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of [[Quantum teleportation#Entanglement swapping|entanglement swapping]]. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<ref>Rosario Lo Franco and Giuseppe Compagno, "Indistinguishability of Elementary Systems as a Resource for Quantum Information Processing", Phys. Rev. Lett. 120, 240403, 14 June 2018.</ref><br />
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=== Testing a system for entanglement ===<br />
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A density matrix ρ is called [[Separable state|separable]] if it can be written as a convex sum of product states, namely<br />
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<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple [[Peres–Horodecki criterion]] provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes [[NP-hard]] when generalized.<ref name="NP-hard1">Gurvits, L., Classical deterministic complexity of Edmonds' problem and quantum entanglement, in Proceedings of the 35th ACM Symposium on Theory of Computing, ACM Press, New York, 2003.</ref><ref name="NP-hard2">Sevag Gharibian, Strong NP-Hardness of the [[Quantum Separability Problem]], [[Quantum Information]] and what's known as [[Quantum Computing]], Vol. 10, No. 3&4, pp. 343–360, 2010. {{arXiv|0810.4507}}.</ref> Other separability criteria include (but not limited to) the [[range criterion]], [[reduction criterion]], and those based on uncertainty relations.<ref>{{cite journal |last1=Hofmann |first1=Holger F. |last2=Takeuchi |first2=Shigeki |title=Violation of local uncertainty relations as a signature of entanglement |journal=Physical Review A |date=22 September 2003 |volume=68 |issue=3 |page=032103 |doi=10.1103/PhysRevA.68.032103|arxiv=quant-ph/0212090 |bibcode=2003PhRvA..68c2103H |s2cid=54893300 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |title=Characterizing Entanglement via Uncertainty Relations |journal=Physical Review Letters |date=18 March 2004 |volume=92 |issue=11 |page=117903 |doi=10.1103/PhysRevLett.92.117903|pmid=15089173 |arxiv=quant-ph/0306194 |bibcode=2004PhRvL..92k7903G |s2cid=5696147 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |last2=Lewenstein |first2=Maciej |title=Entropic uncertainty relations and entanglement |journal=Physical Review A |date=24 August 2004 |volume=70 |issue=2 |page=022316 |doi=10.1103/PhysRevA.70.022316|bibcode=2004PhRvA..70b2316G |arxiv=quant-ph/0403219 |s2cid=118952931 }}</ref><ref>{{cite journal |last1=Huang |first1=Yichen |title=Entanglement criteria via concave-function uncertainty relations |journal=Physical Review A |date=29 July 2010 |volume=82 |issue=1 |page=012335 |doi=10.1103/PhysRevA.82.012335|bibcode=2010PhRvA..82a2335H }}</ref> See Ref.<ref>{{cite journal|last1=Gühne|first1=Otfried|last2=Tóth|first2=Géza|title=Entanglement detection|journal=Physics Reports|volume=474|issue=1–6|pages=1–75|doi=10.1016/j.physrep.2009.02.004|arxiv = 0811.2803 |bibcode = 2009PhR...474....1G |year=2009|s2cid=119288569}}</ref> for a review of separability criteria in discrete variable systems.<br />
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A numerical approach to the problem is suggested by [[Jon Magne Leinaas]], [[Jan Myrheim]] and [[Eirik Ovrum]] in their paper "Geometrical aspects of entanglement".<ref name="geom approach">{{cite journal | last1 = Leinaas| first1 = Jon Magne| last2 = Myrheim| first2 = Jan| last3 = Ovrum| first3 = Eirik| year = 2006 | title = Geometrical aspects of entanglement | url = | journal = Physical Review A | volume = 74 | issue = | page = 012313 | doi = 10.1103/PhysRevA.74.012313| arxiv = quant-ph/0605079| s2cid = 119443360}}</ref> Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in [[Peres-Horodecki criterion]] testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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In continuous variable systems, the [[Peres-Horodecki criterion]] also applies. Specifically, Simon <ref>{{cite journal|last1=Simon|first1=R.|title=Peres-Horodecki Separability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2726–2729|doi=10.1103/PhysRevLett.84.2726|arxiv = quant-ph/9909044 |bibcode = 2000PhRvL..84.2726S|pmid=11017310|year=2000|s2cid=11664720}}</ref> formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref.<ref>{{cite journal|last1=Duan|first1=Lu-Ming|last2=Giedke|first2=G.|last3=Cirac|first3=J. I.|last4=Zoller|first4=P.|title=Inseparability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2722–2725|doi=10.1103/PhysRevLett.84.2722|pmid=11017309|arxiv = quant-ph/9908056 |bibcode = 2000PhRvL..84.2722D |year=2000|s2cid=9948874}}</ref> for a seemingly different but essentially equivalent approach). It was later found <ref>{{cite journal|last1=Werner|first1=R. F.|last2=Wolf|first2=M. M.|title=Bound Entangled Gaussian States|journal=Physical Review Letters|volume=86|issue=16|pages=3658–3661|doi=10.1103/PhysRevLett.86.3658|pmid=11328047|arxiv = quant-ph/0009118 |bibcode = 2001PhRvL..86.3658W |year=2001|s2cid=20897950}}</ref> that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators <ref>{{cite journal|last1=Shchukin|first1=E.|last2=Vogel|first2=W.|title=Inseparability Criteria for Continuous Bipartite Quantum States|journal=Physical Review Letters|volume=95|issue=23|pages=230502|doi=10.1103/PhysRevLett.95.230502|pmid=16384285|arxiv = quant-ph/0508132 |bibcode = 2005PhRvL..95w0502S |year=2005|s2cid=28595936}}</ref><ref>{{cite journal|last1=Hillery|first1=Mark|last2=Zubairy|first2=M.Suhail|title=Entanglement Conditions for Two-Mode States|journal=Physical Review Letters|volume=96|issue=5|doi=10.1103/PhysRevLett.96.050503|arxiv = quant-ph/0507168 |bibcode = 2006PhRvL..96e0503H|pmid=16486912|page=050503|year=2006|s2cid=43756465}}</ref> or by using entropic measures.<ref>{{cite journal|last1=Walborn|first1=S.|last2=Taketani|first2=B.|last3=Salles|first3=A.|last4=Toscano|first4=F.|last5=de Matos Filho|first5=R.|title=Entropic Entanglement Criteria for Continuous Variables|journal=Physical Review Letters|volume=103|issue=16|doi=10.1103/PhysRevLett.103.160505|arxiv = 0909.0147 |bibcode = 2009PhRvL.103p0505W|pmid=19905682|page=160505|year=2009|s2cid=10523704}}</ref><ref>{{cite journal |last1=Yichen Huang |title=Entanglement Detection: Complexity and Shannon Entropic Criteria |journal=IEEE Transactions on Information Theory |date=October 2013 |volume=59 |issue=10 |pages=6774–6778 |doi=10.1109/TIT.2013.2257936|s2cid=7149863 }}</ref><br />
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<br />
In 2016 China launched the world’s first quantum communications satellite.<ref>http://physicsworld.com/cws/article/news/2016/aug/16/china-launches-world-s-first-quantum-science-satellite</ref> The $100m [[Quantum Experiments at Space Scale]] (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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<br />
In the June 16, 2017, issue of ''Science'', Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<ref>{{cite journal | doi = 10.1126/science.aan3211 | volume=356 | title=Satellite-based entanglement distribution over 1200 kilometers | year=2017 | journal=Science | pages=1140–1144 | last1 = Yin | first1 = Juan | last2 = Cao | first2 = Yuan | last3 = Li | first3 = Yu-Huai | last4 = Liao | first4 = Sheng-Kai | last5 = Zhang | first5 = Liang | last6 = Ren | first6 = Ji-Gang | last7 = Cai | first7 = Wen-Qi | last8 = Liu | first8 = Wei-Yue | last9 = Li | first9 = Bo | last10 = Dai | first10 = Hui | last11 = Li | first11 = Guang-Bing | last12 = Lu | first12 = Qi-Ming | last13 = Gong | first13 = Yun-Hong | last14 = Xu | first14 = Yu | last15 = Li | first15 = Shuang-Lin | last16 = Li | first16 = Feng-Zhi | last17 = Yin | first17 = Ya-Yun | last18 = Jiang | first18 = Zi-Qing | last19 = Li | first19 = Ming | last20 = Jia | first20 = Jian-Jun | last21 = Ren | first21 = Ge | last22 = He | first22 = Dong | last23 = Zhou | first23 = Yi-Lin | last24 = Zhang | first24 = Xiao-Xiang | last25 = Wang | first25 = Na | last26 = Chang | first26 = Xiang | last27 = Zhu | first27 = Zhen-Cai | last28 = Liu | first28 = Nai-Le | last29 = Chen | first29 = Yu-Ao | last30 = Lu | first30 = Chao-Yang | last31 = Shu | first31 = Rong | last32 = Peng | first32 = Cheng-Zhi | last33 = Wang | first33 = Jian-Yu | last34 = Pan | first34 = Jian-Wei | issue=6343 | pmid = 28619937| doi-access = free }}</ref><ref>{{cite web | url=http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance | title=China's quantum satellite achieves 'spooky action' at record distance| date=2017-06-14}}</ref><br />
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== Naturally entangled systems ==<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be [[Configuration interaction|calculated]] only by consideration of electron entanglement.<ref>Frank Jensen: ''Introduction to Computational Chemistry.'' Wiley, 2007, {{ISBN|978-0-470-01187-4}}.</ref><br />
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== Photosynthesis ==<br />
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It has been suggested that in the process of [[photosynthesis]], entanglement is involved in the transfer of energy between [[light-harvesting complex]]es and [[photosynthetic reaction center]]s where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using [[femtosecond spectroscopy]], the coherence of entanglement in the [[Fenna-Matthews-Olson complex]] was measured over hundreds of [[femtosecond]]s (a relatively long time in this regard) providing support to this theory.<ref>Berkeley Lab Press Release: ''[http://newscenter.lbl.gov/feature-stories/2010/05/10/untangling-quantum-entanglement/ Untangling the Quantum Entanglement Behind Photosynthesis: Berkeley scientists shine new light on green plant secrets.]''</ref><ref>Mohan Sarovar, Akihito Ishizaki, Graham R. Fleming, K. Birgitta Whaley: ''Quantum entanglement in photosynthetic light harvesting complexes.'' {{arxiv|0905.3787}}</ref><br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<ref>{{cite journal | author = R. Tempelaar | author2 = T. L. C. Jansen | author3 = J. Knoester | title = Vibrational Beatings Conceal Evidence of Electronic Coherence in the FMO Light-Harvesting Complex | journal = J. Phys. Chem. B | volume = 118 | issue = 45 | pages = 12865–12872 | date = 2014 | doi=10.1021/jp510074q| pmid = 25321492 }}</ref><ref>{{cite journal | author = N. Christenson | author2 = H. F. Kauffmann | author3 = T. Pullerits | author4 = T. Mancal | title = Origin of Long-Lived Coherences in Light-Harvesting Complexes| journal = J. Phys. Chem. B | volume = 116 | issue = 25 | pages = 7449–7454 | date = 2012 | doi = 10.1021/jp304649c | pmid = 22642682 | pmc = 3789255 | bibcode = 2012arXiv1201.6325C | arxiv = 1201.6325 }}</ref><ref>{{cite journal | author = A. Kolli | author2 = E. J. O’Reilly | author3= G. D. Scholes | author4= A. Olaya-Castro | title = The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae| journal = J. Chem. Phys. | volume = 137 | issue = 17 | pages = 174109 | date = 2012 | doi=10.1063/1.4764100| pmid = 23145719 | bibcode = 2012JChPh.137q4109K | arxiv = 1203.5056 | s2cid = 20156821 }}</ref><ref>{{cite journal | author = V. Butkus | author2 = D. Zigmantas | author3= L. Valkunas | author4= D. Abramavicius | title = Vibrational vs. electronic coherences in 2D spectrum of molecular systems| journal = Chem. Phys. Lett. | volume = 545 | issue = 30 | pages = 40–43 | date = 2012 | doi=10.1016/j.cplett.2012.07.014| arxiv = 1201.2753 | bibcode = 2012CPL...545...40B | s2cid = 96663719 }}</ref><ref>{{cite journal | author = V. Tiwari | author2 = W. K. Peters | author3= D. M. Jonas | title = Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework | journal = Proc. Natl. Acad. Sci. USA | volume = 110 | issue = 4 | pages = 1203–1208 | date = 2013 | doi=10.1073/pnas.1211157110| pmid = 23267114 | pmc = 3557059 }}</ref><ref>{{cite journal | author = E. Thyrhaug | author2 = K. Zidek | author3 = J. Dostal | author4 = D. Bina | author5 = D. Zigmantas | title = Exciton Structure and Energy Transfer in the Fenna−Matthews− Olson Complex| journal = J. Phys. Chem. Lett. | volume = 7 | issue = 9 | pages = 1653–1660 | date = 2016 | doi=10.1021/acs.jpclett.6b00534| pmid = 27082631 }}</ref><ref>{{cite journal | author = Y. Fujihashi | author2 = G. R. Fleming | author3= A. Ishizaki | title = Impact of environmentally induced fluctuations on quantum mechanically mixed electronic and vibrational pigment states in photosynthetic energy transfer and 2D electronic spectra| journal = J. Chem. Phys. | volume = 142 | issue = 21 | pages = 212403 | date = 2015 | doi=10.1063/1.4914302| pmid = 26049423 | arxiv = 1505.05281 | bibcode = 2015JChPh.142u2403F | s2cid = 1082742 }}</ref><br />
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== Entanglement of macroscopic objects ==<br />
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In 2020 researchers reported the quantum entanglement between the [[Vibrations of a circular membrane|motion of a millimetre-sized mechanical oscillator]] and a disparate distant [[Spin (physics)|spin]] system of a cloud of atoms.<ref>{{cite news |title=Quantum entanglement realized between distant large objects |url=https://phys.org/news/2020-09-quantum-entanglement-distant-large.html |accessdate=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Thomas |first1=Rodrigo A. |last2=Parniak |first2=Michał |last3=Østfeldt |first3=Christoffer |last4=Møller |first4=Christoffer B. |last5=Bærentsen |first5=Christian |last6=Tsaturyan |first6=Yeghishe |last7=Schliesser |first7=Albert |last8=Appel |first8=Jürgen |last9=Zeuthen |first9=Emil |last10=Polzik |first10=Eugene S. |title=Entanglement between distant macroscopic mechanical and spin systems |journal=Nature Physics |date=21 September 2020 |pages=1–6 |doi=10.1038/s41567-020-1031-5 |url=https://www.nature.com/articles/s41567-020-1031-5 |accessdate=9 October 2020 |language=en |issn=1745-2481}}</ref><br />
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=== Entanglement of elements of living systems ===<br />
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In October 2018, physicists reported producing quantum entanglement using [[living organism]]s, particularly between photosynthetic molecules within living [[bacteria]] and [[Photon|quantized light]].<ref name="JPC-20181010">{{cite journal |last1=Marletto |first1=C. |last2=Coles |first2=D.M. |last3=Farrow |first3=T. |last4=Vedral |first4=V. |title=Entanglement between living bacteria and quantized light witnessed by Rabi splitting |date=10 October 2018 |journal=Journal of Physics: Communications |volume=2 |pages=101001 |number=10 |doi=10.1088/2399-6528/aae224 |bibcode=2018JPhCo...2j1001M |arxiv=1702.08075 |s2cid=119236759 }} [[File:CC-BY icon.svg|50px]] Text and images are available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref><ref name="SA-20181029">{{cite web |last=O'Callaghan |first=Jonathan |title="Schrödinger's Bacterium" Could Be a Quantum Biology Milestone – A recent experiment may have placed living organisms in a state of quantum entanglement |url=https://www.scientificamerican.com/article/schroedingers-bacterium-could-be-a-quantum-biology-milestone/ |date=29 October 2018 |work=[[Scientific American]] |accessdate=29 October 2018 }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<ref>{{cite journal | last1 = Krisnanda | first1 = T. | last2 = Marletto | first2 = C. | last3 = Vedral | first3 = V. | last4 = Paternostro | first4 = M. | last5 = Paterek | first5 = T. | year = 2018 | title = Probing quantum features of photosynthetic organisms | url = https://www.nature.com/articles/s41534-018-0110-2 | journal = NPJ Quantum Information | volume = 4 | issue = | page = 60 | doi = 10.1038/s41534-018-0110-2 | doi-access = free }}</ref><br />
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== See also ==<br />
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{{Portal|Physics}}<br />
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* [[Quantum gate#Controlled gates|CNOT gate]]<br />
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* [[Bound entanglement]]<br />
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* [[Concurrence (quantum computing)]]<br />
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* [[Einstein's thought experiments]]<br />
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* [[Entanglement distillation]]<br />
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* [[Entanglement witness]]<br />
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* [[Faster-than-light communication]]<br />
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* [[Ghirardi–Rimini–Weber theory]]<br />
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* [[Multipartite entanglement]]<br />
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* [[Normally distributed and uncorrelated does not imply independent]]<br />
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* [[Observer effect (physics)]]<br />
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* [[Quantum coherence]]<br />
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* [[Quantum discord]]<br />
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* [[Quantum phase transition]]<br />
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* [[Quantum computing]]<br />
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* [[Quantum network]]<br />
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Category:Quantum information science<br />
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类别: 量子信息科学<br />
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* [[Quantum pseudo-telepathy]]<br />
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Category:Quantum mechanics<br />
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类别: 量子力学<br />
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* [[Quantum teleportation]]<br />
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Category:Unsolved problems in physics<br />
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类别: 物理学中未解决的问题<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Quantum entanglement]]. Its edit history can be viewed at [[量子纠缠/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%87%8F%E5%AD%90%E7%BA%A0%E7%BC%A0&diff=21122量子纠缠2021-01-22T06:12:10Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Correlation between measurements of quantum subsystems, even when spatially separated}}<br />
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[[File:SPDC figure.png|right|thumb|275px|[[Spontaneous parametric down-conversion]] process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[[Spontaneous parametric down-conversion process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[自发参量下转换过程可以将光子分裂成具有相互垂直极化的 II 型光子对。]<br />
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{{Quantum mechanics|fundamentals}}<br />
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'''Quantum entanglement''' is a physical phenomenon that occurs when a pair or group of [[particle]]s are generated, interact, or share spatial proximity in a way such that the [[quantum state]] of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the [[principle of locality|disparity between classical and quantum physics]]: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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量子纠缠是一种物理现象,描述的是当一对或一组粒子被产生、相互作用或共享空间邻近性时(包括当粒子被大距离分离时),该对或该组粒子中的每个粒子的量子态都无法独立于其他粒子的态。量子纠缠是经典物理学和量子物理学之间差别悬殊的核心问题:纠缠是量子力学的一个主要特征,而经典力学却没有这种特征。<br />
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[[Measurement#Quantum mechanics|Measurements]] of [[physical properties]] such as [[position (vector)|position]], [[momentum]], [[spin (physics)|spin]], and [[polarization (waves)|polarization]] performed on entangled particles can, in some cases, be found to be perfectly [[correlated]]. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly [[paradox]]ical effects: any measurement of a property of a particle results in an irreversible [[wave function collapse]] of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a property of a particle results in an irreversible wave function collapse of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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在某些情况下,对纠缠粒子的位置、动量、自旋和偏振等物理性质的测量可以被发现是完全相关的。例如,如果一对纠缠粒子的产生使得它们的总自旋已知为零,并且发现一个粒子在第一个轴上具有顺时针自旋,那么在同一个轴上测量的另一个粒子的自旋将被发现是逆时针的。然而,这种行为产生了看似矛盾的效应:对粒子性质的任何测量都会导致该粒子的不可逆波函数崩溃,并将改变原来的量子态。在粒子纠缠的情况下,这样的测量将影响整个纠缠系统。<br />
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Such phenomena were the subject of a 1935 paper by [[Albert Einstein]], [[Boris Podolsky]], and [[Nathan Rosen]],<ref name="Einstein1935"><br />
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Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen, and several papers by Erwin Schrödinger shortly thereafter, describing what came to be known as the EPR paradox. Einstein and others considered such behavior to be impossible, as it violated the local realism view of causality (Einstein referring to it as "spooky action at a distance") and argued that the accepted formulation of quantum mechanics must therefore be incomplete.<br />
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1935年,Albert Einstein,Boris Podolsky 和 Nathan Rosen 发表了一篇论文,此后不久,埃尔温·薛定谔也发表了几篇论文,描述了 EPR 悖论。爱因斯坦和其他人认为这种行为是不可能的,因为它违反了因果关系的局部实在论观点(爱因斯坦称之为“鬼魅般的超距作用”) ,并认为公认的量子力学公式因此是不完整的。<br />
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{{cite journal|author=Einstein A, Podolsky B, Rosen N|last2=Podolsky|last3=Rosen|year=1935|title=Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?|journal=Phys. Rev.|volume=47|issue=10|pages=777–780|bibcode=1935PhRv...47..777E|doi=10.1103/PhysRev.47.777|doi-access=free}}<br />
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</ref> and several papers by [[Erwin Schrödinger]] shortly thereafter,<ref name="Schrödinger1935"><br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<br />
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然而,后来,量子力学的违反直觉的预测被实验证实了。然而,所谓的“无漏洞”贝尔测试已经进行,在这个测试中,位置被分开,以光速进行通信所需的时间将会更长——在一个实验中,比测量间隔时间长10000倍。<br />
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{{cite journal<br />
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According to some interpretations of quantum mechanics, the effect of one measurement occurs instantly. Other interpretations which don't recognize wavefunction collapse dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces correlation between the measurements and that the mutual information between the entangled particles can be exploited, but that any transmission of information at faster-than-light speeds is impossible.<br />
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根据一些量子力学诠释的研究,一次测量的效果会立即出现。其他不承认波函数塌缩的解释则质疑其中是否存在任何“效果”。然而,所有的解释都一致认为纠缠态产生了测量之间的相关性,纠缠态粒子之间的相互信息可以利用,但是任何信息的传输都不可能达到超光速。<br />
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|title=Discussion of probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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Quantum entanglement has been demonstrated experimentally with photons, neutrinos, electrons, molecules as large as buckyballs, and even small diamonds. The utilization of entanglement in communication, computation and quantum radar is a very active area of research and development.<br />
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量子纠缠已经通过光子、中微子、电子、巴基球大小的分子甚至是小钻石的实验得到了证实。纠缠在通信、计算和量子雷达中的应用是一个非常活跃的研究领域。<br />
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Article headline regarding the [[Einstein–Podolsky–Rosen paradox (EPR paradox) paper, in the May 4, 1935 issue of The New York Times.]]<br />
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文章标题关于[爱因斯坦-波多尔斯基-罗森悖论(EPR paradox)论文,发表于1935年5月4日的《纽约时报》]<br />
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|year=1935<br />
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|doi=10.1017/S0305004100013554<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.<br />
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1935年,Albert Einstein 在与 Boris Podolsky 和 Nathan Rosen 的联合论文中首次讨论了量子力学关于强相关系统的违反直觉的预测。<br />
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|bibcode = 1935PCPS...31..555S }}</ref><ref name="Schrödinger1936"><br />
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{{cite journal |author=Schrödinger E<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated: Einstein later famously derided entanglement as "spukhafte Fernwirkung" or "spooky action at a distance."<br />
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此后不久,薛定谔发表了一篇影响深远的论文,定义并讨论了“纠缠”的概念在论文中,他承认了这个概念的重要性,并指出: 爱因斯坦后来著名地嘲笑纠缠为“ spukhafte Fernwirkung”或“幽灵般的超距作用”<br />
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|title=Probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously Bohm's interpretation of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when John Stewart Bell proved that one of their key assumptions, the principle of locality, as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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这篇 EPR 论文在物理学家中引起了极大的兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是 Bohm 对量子力学的解释) ,但是其他发表的工作相对较少。尽管如此,EPR 论证中的弱点直到1964年才被发现,当时约翰·斯图尔特·贝尔证明了他们的一个关键假设---- 应用于 EPR 所希望的那种隐变量解释的定域性原理,在数学上与量子理论的预测不一致。<br />
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Specifically, Bell demonstrated an upper limit, seen in Bell's inequality, regarding the strength of correlations that can be produced in any theory obeying local realism, and showed that quantum theory predicts violations of this limit for certain entangled systems. His inequality is experimentally testable, and there have been numerous relevant experiments, starting with the pioneering work of Stuart Freedman and John Clauser in 1972 and Alain Aspect's experiments in 1982. An early experimental breakthrough was due to Carl Kocher, Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles. Alain Aspect notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / superdeterminism loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<br />
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具体来说,贝尔证明了一个上限,可以在贝尔不等式中看到,关于在任何服从局部实在论的理论中都可以产生的相关性的强度,并且显示了量子理论预测了某些纠缠系统违反这个上限。他的不等式在实验上是可以检验的,并且已经有了大量的相关实验,从1972年斯图尔特 · 弗里德曼和约翰 · 克劳泽的开创性工作和1982年阿兰 · 阿斯派克特的实验开始。一个早期的实验突破是由于 Carl Kocher 的仪器,Kocher 的仪器配备了更好的偏振器,被 Freedman 和 Clauser 使用,他们可以证实余弦平方相关性,并用它来证明对一组固定角度的 Bell 不等式的违反。阿兰 · 阿斯派克特指出,“设置独立性漏洞”——他称之为“牵强附会” ,然而,一个“不可忽视”的“残余漏洞”——尚未被关闭,自由意志/超决定论是不可忽视的; 他说,“没有任何实验,尽管理想,可以说是完全没有漏洞的。”<br />
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|pages=446–452<br />
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A minority opinion holds that although quantum mechanics is correct, there is no superluminal instantaneous action-at-a-distance between entangled particles once the particles are separated.<br />
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少数人认为,尽管量子力学是正确的,但是一旦粒子分离,纠缠的粒子之间并不存在超光速瞬时作用。<br />
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|doi=10.1017/S0305004100019137<br />
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|bibcode = 1936PCPS...32..446S }}<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of quantum key distribution protocols, most famously BB84 by Charles H. Bennett and Gilles Brassard and E91 by Artur Ekert. Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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贝尔的工作提高了利用这些超强相关性作为沟通资源的可能性。它导致了1984年量子密钥分配协议的发现,其中最著名的是由 Charles h. Bennett 和 Gilles Brassard 提出的 BB84,以及由 Artur Ekert 提出的 E91。虽然 BB84不使用纠缠,但是 Ekert 的协议使用违反 Bell 不等式作为安全性的证据。<br />
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</ref> describing what came to be known as the [[EPR paradox]]. Einstein and others considered such behavior to be impossible, as it violated the [[local realism]] view of causality (Einstein referring to it as "spooky [[action at a distance]]")<ref>Physicist John Bell depicts the Einstein camp in this debate in his article entitled "Bertlmann's socks and the nature of reality", p. 143 of ''Speakable and unspeakable in quantum mechanics'': "For EPR that would be an unthinkable 'spooky action at a distance'. To avoid such action at a distance they have to attribute, to the space-time regions in question, real properties in advance of observation, correlated properties, which predetermine the outcomes of these particular observations. Since these real properties, fixed in advance of observation, are not contained in quantum formalism, that formalism for EPR is incomplete. It may be correct, as far as it goes, but the usual quantum formalism cannot be the whole story." And again on p. 144 Bell says: "Einstein had no difficulty accepting that affairs in different places could be correlated. What he could not accept was that an intervention at one place could influence, immediately, affairs at the other." Downloaded 5 July 2011 from {{cite book |year=1987 |accessdate=2014-06-14 |title=Speakable and Unspeakable in Quantum Mechanics |first=J. S. |last=Bell |publisher=[[CERN]] |isbn=0521334950 |url=http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20150412044550/http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |archivedate=12 April 2015 |df=dmy-all }}</ref> and argued that the accepted formulation of [[quantum mechanics]] must therefore be incomplete.<br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally<ref name=":0" /><ref name=":1" /><ref name=":2" /> in tests in which polarization or spin of entangled particles were measured at separate locations, statistically violating [[Bell's inequality]]. In earlier tests, it couldn't be absolutely ruled out that the test result at one point could have been [[Loopholes in Bell test experiments|subtly transmitted]] to the remote point, affecting the outcome at the second location.<ref name=":2">Francis, Matthew.<br />
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[https://arstechnica.com/science/2012/10/quantum-entanglement-shows-that-reality-cant-be-local/ Quantum entanglement shows that reality can't be local], ''Ars Technica'', 30 October 2012</ref> However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<ref name=":1">{{cite journal|last1=Matson|first1=John|title=Quantum teleportation achieved over record distances|journal=Nature News|date=13 August 2012|doi=10.1038/nature.2012.11163|s2cid=124852641}}</ref><ref name=":0">{{cite journal<br />
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| title =Bounding the speed of 'spooky action at a distance<br />
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An entangled system is defined to be one whose quantum state cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or superposition, of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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量子纠缠系统的定义是: 量子态不能被分解为其局部成分的状态的产物; 也就是说,它们不是单个的粒子,而是一个不可分割的整体。在纠缠中,一个成分不能不考虑其他成分而被完全描述。复合系统的状态总是可以表示为局部组分状态的产物的和或叠加; 如果这个和必然有多个项,则它是纠缠的。<br />
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| journal =Physical Review Letters |volume=110 | issue =26 |page=260407<br />
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| year =2013<br />
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Quantum systems can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on methods. Entanglement is broken when the entangled particles decohere through interaction with the environment; for example, when a measurement is made.<br />
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量子系统可以通过各种类型的相互作用而纠缠在一起。关于一些可以用于实验目的的纠缠方法,请参阅下面的方法一节。当纠缠的粒子通过与环境的相互作用退相干时,纠缠就被打破了; 例如,当进行测量时。<br />
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| arxiv =1303.0614<br />
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| bibcode =2013PhRvL.110z0407Y<br />
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As an example of entanglement: a subatomic particle decays into an entangled pair of other particles. The decay events obey the various conservation laws, and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a spin-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be spin up on some axis, the other, when measured on the same axis, is always found to be spin down. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the singlet state.)<br />
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作为纠缠的一个例子: 一个次原子粒子衰变成一对纠缠的其他粒子。衰变事件遵循不同的守恒定律,因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(因此总动量、角动量、能量等在此过程前后大致相同)。例如,一个自旋为零的粒子可以衰变成一对自旋为1的粒子。由于衰变前后的总自旋必须为零(角动量守恒定律) ,每当第一个粒子在某一轴上被测量为自旋向上时,另一个粒子在同一轴上被测量时,总是被发现自旋向下。(这就是所谓的自旋反关联情况,如果测量每个自旋的先验概率是相等的,那么这对自旋就处于单线态。)<br />
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| doi = 10.1103/PhysRevLett.110.260407<br />
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| pmid =23848853 | last1 =Yin | first1 =Juan | last2 =Cao | first2 =Yuan | last3 =Yong | first3 =Hai-Lin | last4 =Ren | first4 =Ji-Gang | last5 =Liang | first5 =Hao | last6 =Liao | first6 =Sheng-Kai | last7 =Zhou | first7 =Fei | last8 =Liu | first8 =Chang | last9 =Wu | first9 =Yu-Ping | last10 =Pan | first10 =Ge-Sheng | last11 =Li | first11 =Li | last12 =Liu | first12 =Nai-Le | last13 =Zhang | first13 =Qiang | last14 =Peng | first14 =Cheng-Zhi | last15 =Pan | first15 =Jian-Wei | s2cid =119293698 }}</ref><br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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如果将这两种粒子分开,可以更好地观察到纠缠的特性。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫。现在,如果我们测量其中一个粒子的特性(比如自旋) ,得到一个结果,然后用同样的标准(沿着同样的轴自旋)测量另一个粒子,我们发现第二个粒子的测量结果将匹配(在补充意义上)第一个粒子的测量结果,因为它们的值将相反。<br />
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According to ''some'' [[interpretations of quantum mechanics]], the effect of one measurement occurs instantly. Other interpretations which don't recognize [[wavefunction collapse]] dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces ''[[correlation]]'' between the measurements and that the [[mutual information]] between the entangled particles can be exploited, but that any ''transmission'' of information at faster-than-light speeds is impossible.<ref>[[Roger Penrose]], ''The Road to Reality: A Complete Guide to the Laws of the Universe'', London, 2004, p. 603.</ref><ref name="Griffiths2004">{{citation | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |isbn= 978-0-13-111892-8}}</ref><br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a hidden variable theory (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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上述结果可能会也可能不会让人感到惊讶。一个经典的系统将显示相同的属性,并且一个隐变量理论系统(见下文)当然会被要求这样做,基于古典的和类似的角动量守恒定律量子力学系统。不同之处在于,一个经典系统对所有的可观测量一直都有确定的值,而量子系统则没有。在下面将要讨论的某种意义上,这里所考虑的量子系统似乎获得了一个概率分布,用于在测量第一个粒子时,测量沿着其他粒子的任何轴线的自旋。这个概率分布粒子通常不同于没有第一个粒子测量的情况。在空间分离的纠缠粒子的情况下,这当然可能被认为是令人惊讶的。<br />
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Quantum entanglement has been demonstrated experimentally with [[photon]]s,<ref name="Kocher1">{{cite journal | doi = 10.1103/PhysRevLett.18.575 | volume=18 | issue=15 | title=Polarization Correlation of Photons Emitted in an Atomic Cascade | journal=Physical Review Letters | pages=575–577 | last1 = Kocher | first1 = CA | last2 = Commins | first2 = ED | year=1967| url=http://www.escholarship.org/uc/item/1kb7660q | bibcode=1967PhRvL..18..575K }}</ref><ref name="Kocherphd">Carl A. Kocher, Ph.D. Thesis (University of California at Berkeley, 1967). ''[https://escholarship.org/uc/item/1kb7660q Polarization Correlation of Photons Emitted in an Atomic Cascade]''</ref> [[neutrino]]s,<ref>J. A. Formaggio, D. I. Kaiser, M. M. Murskyj, and T. E. Weiss (2016), "[https://journals.aps.org/prl/accepted/6f072Y00C3318d41f5739ec7f83a9acf1ad67b002 Violation of the Leggett-Garg inequality in neutrino oscillations]". ''Phys. Rev. Lett.'' Accepted 23 June 2016.</ref> [[electron]]s,<ref name="NTR-20151021">{{cite journal |author=Hensen, B. |title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres |date=21 October 2015 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature15759 |display-authors=etal |volume=526 |issue=7575 |pages=682–686|bibcode = 2015Natur.526..682H |pmid=26503041|arxiv=1508.05949 |hdl=2117/79298 |s2cid=205246446 }} See also [http://www.nature.com/articles/nature15759.epdf?referrer_access_token=1QB20mTNTZW60nEXil0D79RgN0jAjWel9jnR3ZoTv0Pfu6MWINxm4Io03p2jIRZ8qX_3I3N0Kr-AlItuikCZOJrG8QbdRRghlecFwmixlbQpWuw1dtaib4Le5DQOG3u_aXHU85x1JEhOcQTa1sHi0yvW23bblxmEQZAmHL4G0gIVusG_6JWorroY5BprgbTl4FiaE8WltEgMoUMZfZBkEfbMcFDp5iR112TFx_x3ZRj88Wa23E2moEvTfKjtlued0&tracking_referrer=www.nytimes.com free online access version].</ref><ref name="NYT-20151021">{{cite news |last=Markoff |first=Jack |title=Sorry, Einstein. Quantum Study Suggests 'Spooky Action' Is Real. |url=https://www.nytimes.com/2015/10/22/science/quantum-theory-experiment-said-to-prove-spooky-interactions.html |date=21 October 2015 |work=The New York Times |accessdate=21 October 2015 }}</ref> [[molecule]]s as large as [[buckyball]]s,<ref>{{cite journal | doi = 10.1038/44348 | title = Wave–particle duality of C<sub>60</sub> molecules | date= 14 October 1999 | volume=401 | issue = 6754 | journal=Nature | pages=680–682 | pmid=18494170|bibcode = 1999Natur.401..680A | last1 = Arndt | first1 = M | last2 = Nairz | first2 = O | last3 = Vos-Andreae | first3 = J | last4 = Keller | first4 = C | last5 = van der Zouw | first5 = G | last6 = Zeilinger | first6 = A| s2cid = 4424892 }} {{subscription}}</ref><ref>[[Olaf Nairz]], [[Markus Arndt]], and [[Anton Zeilinger]], "Quantum interference experiments with large molecules", American Journal of Physics, 71 (April 2003) 319–325.</ref> and even small diamonds.<ref>{{cite journal |journal=Science |date=2 December 2011 |volume=334 |issue=6060 |pages=1253–1256 |doi=10.1126/science.1211914 |pmid=22144620 |url=http://www.sciencemag.org/content/334/6060/1253.full |title=Entangling macroscopic diamonds at room temperature |lay-url=https://www.newscientist.com/article/dn21235-entangled-diamonds-blur-quantumclassical-divide.html|bibcode = 2011Sci...334.1253L |last1=Lee |first1=K. C. |last2=Sprague |first2=M. R. |last3=Sussman |first3=B. J. |last4=Nunn |first4=J. |last5=Langford |first5=N. K. |last6=Jin |first6=X.- M. |last7=Champion |first7=T. |last8=Michelberger |first8=P. |last9=Reim |first9=K. F. |last10=England |first10=D. |last11=Jaksch |first11=D. |last12=Walmsley |first12=I. A. |s2cid=206536690 }}</ref><ref>[http://www.sciencemag.org/content/334/6060/1253/suppl/DC1 sciencemag.org], supplementary materials</ref> The utilization of entanglement in [[quantum communication|communication]], [[quantum computing|computation]] and [[quantum radar]] is a very active area of research and development.<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<br />
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矛盾的是,对任何一个粒子的测量显然会破坏整个纠缠系统的状态,而且是在测量结果的任何信息可以传递给另一个粒子之前(假设信息不能比光传播得更快) ,从而确保对纠缠对的另一部分的测量结果是“适当的”。在哥本哈根诠释中,对其中一个粒子进行自旋测量的结果是一个崩塌状态,在这个状态中,每个粒子沿测量轴都有一个确定的自旋(上或下)。结果是随机的,每种可能性的概率都是50% 。然而,如果两个自旋都沿着同一个轴测量,就会发现它们是反相关的。这意味着对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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== History ==<br />
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[[File:NYT May 4, 1935.jpg|right|thumb| 250px|Article headline regarding the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox) paper, in the May 4, 1935 issue of ''[[The New York Times]]''.]]<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, hence, any causal effect connecting the events would have to travel faster than light. According to the principles of special relativity, it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events and there are inertial frames in which is first and others in which is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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可以选择测量的距离和时间,使两个测量之间的间隔类似于空间,因此,任何连接事件的因果效应都必须比光传播得更快。根据狭义相对论原理,任何信息都不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量结果是最先出现的。对于两个类空分离的事件,存在惯性系,其中一个是第一个,其他的是第一个。因此,两个测量值之间的相关性不能解释为一个测量值决定另一个测量值: 不同的观察者会对因果的作用有不同的看法。<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by [[Albert Einstein]] in 1935, in a joint paper with [[Boris Podolsky]] and [[Nathan Rosen]].<ref name="Einstein1935"/><br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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(事实上,即使没有纠缠也会出现类似的悖论: 单个粒子的位置分布在空间上,两个相距很远的探测器试图在两个不同的地方探测粒子,必须同时达到适当的相关性,以便它们不能同时探测粒子。)<br />
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In this study, the three formulated the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox), a [[thought experiment]] that attempted to show that [[quantum mechanics|quantum mechanical theory]] was [[Incompleteness of quantum physics|incomplete]]. They wrote: "We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete."<ref name="Einstein1935"/><br />
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However, the three scientists did not coin the word ''entanglement'', nor did they generalize the special properties of the state they considered. Following the EPR paper, [[Erwin Schrödinger]] wrote a letter to Einstein in [[German language|German]] in which he used the word ''Verschränkung'' (translated by himself as ''entanglement'') "to describe the correlations between two particles that interact and then separate, as in the EPR experiment."<ref name=MK>Kumar, M., ''Quantum'', Icon Books, 2009, p. 313.</ref><br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables". The state of the particles being measured contains some hidden variables, whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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这一悖论的一个可能的解决办法是假定量子理论是不完整的,测量结果取决于预先确定的“隐变量”。被测粒子的状态包含一些隐藏的变量,它们的值有效地决定了,从分离的那一刻起,自旋测量的结果将会是什么。这意味着每个粒子都携带着所需的所有信息,在测量时不需要从一个粒子传递到另一个粒子。爱因斯坦和其他人(见上一节)最初认为这是唯一的出路的悖论,和公认的量子力学描述(随机测量结果)必须是不完整的。<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated:<ref name="Schrödinger1935"/> "I would not call [entanglement] ''one'' but rather ''the'' characteristic trait of [[quantum mechanics]], the one that enforces its entire departure from [[Classical mechanics|classical]] lines of thought."<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the local realist or hidden variables view were correct, the results would always satisfy Bell's inequality. A number of experiments have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists. When measurements of the entangled particles are made in moving relativistic reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<br />
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然而,当考虑沿不同轴线的纠缠粒子的自旋时,局部隐变量理论就失败了。如果在大量的纠缠粒子对上进行了大量的这样的测量,那么从统计学上来说,如果局域实在论或隐变量观点是正确的,那么结果总是满足 Bell 不等式。许多实验表明,贝尔不等式在实践中并不能得到满足。然而,在2015年之前,所有这些都存在漏洞问题,这被物理学界认为是最重要的。当在移动的相对论参照系中测量纠缠粒子时,每个测量(在其自身的相对论时间框架内)先于另一个进行,测量结果仍然是相关的。<br />
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Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the [[theory of relativity]].<ref>Alisa Bokulich, Gregg Jaeger, ''Philosophy of Quantum Information and Entanglement'', Cambridge University Press, 2010, xv.</ref> Einstein later famously derided entanglement as "''spukhafte Fernwirkung''"<ref name="spukhafte">Letter from Einstein to Max Born, 3 March 1947; ''The Born-Einstein Letters; Correspondence between Albert Einstein and Max and Hedwig Born from 1916 to 1955'', Walker, New York, 1971. (cited in {{citation | title = Quantum Entanglement and Communication Complexity (1998) | journal = SIAM J. Comput. | volume = 30 | issue = 6 | citeseerx = 10.1.1.20.8324 | author = M. P. Hobson |pages=1829–1841 | display-authors = etal | year = 1998 }})</ref> or "spooky [[Action at a distance (physics)|action at a distance]]."<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are incompatible in the sense that these measurements' maximum simultaneous precision is constrained by the uncertainty principle. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations, and thus entanglement is a fundamentally non-classical phenomenon.<br />
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沿不同轴线测量自旋的基本问题是,这些测量不可能同时具有确定的值——它们是不相容的,因为这些测量的最大同时精度受到不确定性原理的限制。这与经典物理学中的发现相反,在经典物理学中,任何数量的性质都可以以任意精度同时测量。从数学上证明了相容测量不能显示违反贝尔不等式的关联,因此纠缠是一个基本的非经典现象。<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously [[De Broglie–Bohm theory|Bohm's interpretation]] of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when [[John Stewart Bell]] proved that one of their key assumptions, the [[principle of locality]], as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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Entanglement is required to preserve the Uncertainty principle, as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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纠缠是保持不确定性原理所必需的,如 EPR 悖论所示。例如,假设一个高能光子衰变成一个电子/正电子对,然后测量电子的位置和正电子的动量。如果我们在物理描述中不允许纠缠,那么每个粒子的位置和动量仍然可以通过参考动量守恒来推导,这违反了测不准原理。或者,如果我们要求不确定性原理保持真实,而仍然不允许在物理描述对的纠缠,不确定性原理将允许违反动量守恒定律,因为在位置和动量上强相关性是不可能的(也就是说,人们不能有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关)。--><br />
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Specifically, Bell demonstrated an upper limit, seen in [[Bell's inequality]], regarding the strength of correlations that can be produced in any theory obeying [[local realism]], and showed that quantum theory predicts violations of this limit for certain entangled systems.<ref>{{cite journal |author = J. S. Bell |title = On the Einstein-Poldolsky-Rosen paradox |journal = Physics Physique Физика |volume = 1 |issue = 3 |pages = 195–200 |year = 1964|doi = 10.1103/PhysicsPhysiqueFizika.1.195 |doi-access = free }}</ref> His inequality is experimentally testable, and there have been numerous [[Bell test experiments|relevant experiments]], starting with the pioneering work of [[Stuart Freedman]] and [[John Clauser]] in 1972<ref name="Clauser">{{cite journal|doi=10.1103/PhysRevLett.28.938|last1=Freedman|first1=Stuart J.|last2=Clauser|first2=John F.|title=Experimental Test of Local Hidden-Variable Theories|journal=Physical Review Letters |volume=28 |issue=14 |pages=938–941|year=1972 |bibcode=1972PhRvL..28..938F|url=https://escholarship.org/uc/item/2f18n5nk}}</ref> and [[Alain Aspect]]'s experiments in 1982.<ref>{{cite journal |author1=A. Aspect |author2=P. Grangier |author3=G. Roger |name-list-style=amp |title = Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell's Inequalities |journal = Physical Review Letters |volume = 49 |issue = 2 |pages = 91–94 |year = 1982 |doi = 10.1103/PhysRevLett.49.91 |bibcode=1982PhRvL..49...91A|doi-access = free }}</ref> An early experimental breakthrough was due to Carl Kocher,<ref name="Kocher1"/><ref name="Kocherphd"/> who already in 1967 presented an apparatus in which two photons successively emitted from a calcium atom were shown to be entangled – the first case of entangled visible light. The two photons passed diametrically positioned parallel polarizers with higher probability than classically predicted but with correlations in quantitative agreement with quantum mechanical calculations. He also showed that the correlation varied only upon (as cosine square of) the angle between the polarizer settings<ref name="Kocherphd"/> and decreased exponentially with time lag between emitted photons.<ref name="Kocher2">{{cite journal | doi = 10.1016/0003-4916(71)90159-X | volume=65 | issue=1 | title=Time correlations in the detection of successively emitted photons | journal=Annals of Physics | pages=1–18 | last1 = Kocher | first1 = CA | year=1971| bibcode=1971AnPhy..65....1K }}</ref> Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles.<ref name="Clauser"/> All these experiments have shown agreement with quantum mechanics rather than the principle of local realism.<br />
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For decades, each had left open at least one [[Loopholes in Bell test experiments|loophole]] by which it was possible to question the validity of the results. However, in 2015 an experiment was performed that simultaneously closed both the detection and locality loopholes, and was heralded as "loophole-free"; this experiment ruled out a large class of local realism theories with certainty.<ref name="hanson">{{cite journal|last1=Hanson|first1=Ronald|title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres|journal=Nature|volume=526|issue=7575|pages=682–686|doi=10.1038/nature15759|arxiv=1508.05949|bibcode = 2015Natur.526..682H|pmid=26503041|year=2015|s2cid=205246446}}</ref> [[Alain Aspect]] notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / ''[[superdeterminism]]'' loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<ref>{{Cite journal | title=Viewpoint: Closing the Door on Einstein and Bohr's Quantum Debate| journal=Physics| volume=8| date=2015-12-16| last1=Aspect| first1=Alain| page=123| doi=10.1103/physics.8.123| doi-access=free| bibcode=2015PhyOJ...8..123A}}</ref><br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time. The authors claimed that this result was achieved by entanglement swapping between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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在2012年和2013年的实验中,光子之间产生了偏振相关性,这种相关性从未在时间上共存过。作者认为,这一结果是通过测量早期纠缠光子对中一个光子的偏振态后,两对纠缠光子之间的纠缠交换实现的,并且证明了量子非局域性不仅适用于空间,也适用于时间。<br />
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A minority opinion holds that although quantum mechanics is correct, there is no [[faster-than-light|superluminal]] instantaneous action-at-a-distance between entangled particles once the particles are separated.<ref>{{Cite journal |doi = 10.1142/S0217979206034078|title = Correlations in Entangled States|journal = International Journal of Modern Physics B|volume = 20|issue = 11n13|pages = 1496–1503|year = 2006|last1 = Sanctuary|first1 = B. C|arxiv = quant-ph/0508238|bibcode = 2006IJMPB..20.1496S|s2cid = 119403050}}</ref><ref>{{Cite arxiv |eprint = quant-ph/0404011 |last1 = Yin |first1 = Juan |title = The Statistical Interpretation of Entangled States |last2 = Cao |first2 = Yuan |last3 = Yong |first3 = Hai-Lin |last4 = Ren |first4 = Ji-Gang |last5 = Liang |first5 = Hao |last6 = Liao |first6 = Sheng-Kai |last7 = Zhou |first7 = Fei |last8 = Liu |first8 = Chang |last9 = Wu |first9 = Yu-Ping |last10 = Pan |first10 = Ge-Sheng |last11 = Zhang |first11 = Qiang |last12 = Peng |first12 = Cheng-Zhi |last13 = Pan |first13 = Jian-Wei |year = 2004 }}</ref><ref>{{cite journal|doi=10.1002/prop.201600044 | volume=65 | issue=6–8 | title=After Bell | year=2016 | journal=Fortschritte der Physik | page=1600044 | last1 = Khrennikov | first1 = Andrei}}</ref><ref>{{Cite journal |arxiv = 1603.08674|last1 = Yin|first1 = Juan|title = After Bell|journal = Fortschritte der Physik (Progress in Physics)|date=2017|volume = 65|issue = 1600014|pages = 6–8|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|bibcode = 2016arXiv160308674K}}</ref><ref>{{Cite journal |arxiv = quant-ph/0703251|last1 = Yin|first1 = Juan|title = Classical statistical distributions can violate Bell-type inequalities|journal = Journal of Physics A: Mathematical and Theoretical|volume = 41|issue = 8|pages = 085303|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|year = 2007|doi = 10.1088/1751-8113/41/8/085303|s2cid = 46193162}}</ref><br />
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In three independent experiments in 2013 it was shown that classically communicated separable quantum states can be used to carry entangled states. The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<br />
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在2013年的三个独立实验中,我们发现经典通信的可分离量子态可以用来携带纠缠态。2015年,TU Delft 进行了第一次没有漏洞的贝尔测试,证实了贝尔不平等的违规性。<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of [[quantum key distribution]] protocols, most famously [[BB84]] by [[Charles H. Bennett (computer scientist)|Charles H. Bennett]] and [[Gilles Brassard]]<ref>C. H. Bennett and G. Brassard. "Quantum cryptography: Public key distribution and coin tossing". In ''Proceedings of IEEE International Conference on Computers, Systems and Signal Processing'', volume 175, p. 8. New York, 1984. http://researcher.watson.ibm.com/researcher/files/us-bennetc/BB84highest.pdf</ref> and [[E91 protocol|E91]] by [[Artur Ekert]].<ref>{{cite journal|last=Ekert|first=A.K.|authorlink=Artur Ekert|title=Quantum cryptography based on Bell's theorem|journal=Phys. Rev. Lett.|volume=67|issue=6|year=1991|doi=10.1103/PhysRevLett.67.661|issn=0031-9007|bibcode = 1991PhRvL..67..661E|pmid=10044956|pages=661–663}}</ref> Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<br />
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2014年8月,巴西研究人员加布里埃拉 · 巴雷托 · 莱莫斯和他的团队能够使用光子“拍摄”物体,这些光子并没有与实验对象发生相互作用,而是与这些物体发生了纠缠。来自维也纳大学的勒莫斯相信,这种新的量子成像技术可以在微光成像势在必行的领域找到应用,比如生物或医学成像。<br />
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== Concept ==<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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2015年,哈佛大学的 Markus Greiner 团队直接测量了超冷玻色子原子系统中的 Renyi 纠缠。<br />
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=== Meaning of entanglement ===<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<br />
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从2016年开始,各种各样的公司,如 IBM,微软等。已经成功地创造了量子计算机,并且允许开发者和技术爱好者公开地实验量子力学的概念,包括量子纠缠。<br />
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An entangled system is defined to be one whose [[quantum state]] cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or [[quantum superposition|superposition]], of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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Quantum [[physical system|systems]] can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on [[#Methods of creating entanglement|methods]]. Entanglement is broken when the entangled particles [[quantum decoherence|decohere]] through interaction with the environment; for example, when a measurement is made.<ref name="Peres1993">Asher Peres, ''[[Quantum Theory: Concepts and Methods]]'', Kluwer, 1993; {{ISBN|0-7923-2549-4}} p. 115.</ref><br />
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There have been suggestions to look at the concept of time as an emergent phenomenon that is a side effect of quantum entanglement.<br />
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有人建议把时间的概念看作是量子纠缠的副作用的一种自然现象。<br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by Don Page and William Wootters in 1983.<br />
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换句话说,时间是一种纠缠现象,它将所有相同的时钟读数(正确准备的时钟,或任何可用作时钟的物体)置于同一历史中。这是唐 · 佩奇和威廉 · 伍特斯在1983年首次提出的完整理论。<br />
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As an example of entanglement: a [[subatomic particle]] [[Particle decay|decays]] into an entangled pair of other particles. The decay events obey the various [[conservation laws]], and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a [[Spin (physics)|spin]]-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be [[Spin (physics)#Direction|spin up]] on some axis, the other, when measured on the same axis, is always found to be [[Spin (physics)#Direction|spin down]]. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the [[singlet state]].)<br />
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The Wheeler–DeWitt equation that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<br />
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20世纪60年代,惠勒-德威特方程引入了广义相对论和量子力学的概念,并于1983年再次引入,当时佩奇和伍特基于量子纠缠方程提出了一个解决方案。佩奇和伍特斯认为纠缠态可以用来测量时间。<br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts. The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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2013年,在意大利都灵的国家理查尔卡计量研究所(INRIM) ,研究人员对佩奇和伍特的想法进行了首次实验测试。他们的结果被解释为证实了对于内部观察者来说时间是一种涌现的现象,但正如惠勒-德威特方程所预测的那样,对于宇宙的外部观察者来说时间是不存在的。纠缠的方法是从因果时间箭头的角度出发,假设一个粒子被测量的原因决定了另一个粒子测量结果的影响。<br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a [[hidden variable theory]] (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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===Paradox===<br />
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Based on AdS/CFT correspondence, Mark Van Raamsdonk suggested that spacetime arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time. Induced gravity can emerge from the entanglement first law.<br />
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基于 AdS/CFT对偶的理论,Mark Van Raamsdonk 提出时空是作为量子自由度的一种涌现现象而产生的,这种量子自由度是纠缠在一起的,生活在时空的边界上。诱导引力可以产生于纠缠第一定律。<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel [[faster than light]]) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the [[Copenhagen interpretation]], the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<ref>{{cite book|last1=Rupert W.|first1=Anderson|title=The Cosmic Compendium: Interstellar Travel|date=28 March 2015|publisher=The Cosmic Compendium|isbn=9781329022027|page=100|edition=First|url=https://books.google.com/books?id=JxauCQAAQBAJ&pg=PA100&lpg=PA100&dq=The+outcome+is+taken+to+be+random,+with+each+possibility+having+a+probability+of+50%25.+However,+if+both+spins+are+measured+along+the+same+axis,+they+are+found+to+be+anti-correlated.+This+means+that+the+random+outcome+of+the+measurement+made+on+one+particle+seems+to+have+been+transmitted+to+the+other,+so+that+it+can+make+the+%22right+choice%22+when+it+too+is+measured#v=onepage}}</ref><br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements [[spacelike]], hence, any causal effect connecting the events would have to travel faster than light. According to the principles of [[special relativity]], it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events {{math|''x''<sub>1</sub>}} and {{math|''x''<sub>2</sub>}} there are [[inertial frame]]s in which {{math|''x''<sub>1</sub>}} is first and others in which {{math|''x''<sub>2</sub>}} is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations. A well-known example is the Werner states that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables. Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<br />
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在媒体和流行科学中,量子非定域性经常被描述为等价于纠缠。虽然这对于纯二体量子态来说是正确的,但是一般来说纠缠只对于非局域关联是必要的,但是存在混合纠缠态,不产生这样的关联。一个众所周知的例子是 Werner 状态,它纠缠于 < math > p _ { sym } </math > 的某些值,但总是可以使用局部隐变量来描述。此外,研究还表明,对于任意数目的当事人,存在真正纠缠但承认局部模型的状态。<br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all distillable states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<br />
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上述关于局域模型存在性的证明假设一次只有一个量子态的副本可用。如果允许各方对这些状态的许多副本进行局部测量,那么许多表面上的局部状态(例如,量子位维尔纳状态)就不能再用局部模型来描述。对于所有的可提取态来说,情况尤其如此。然而,如果给定足够多的副本,是否所有纠缠态都成为非局域态,这仍然是一个有待解决的问题。<br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to quantum teleportation and to superdense coding, whereas non-locality is defined according to experimental statistics and is much more involved with the foundations and interpretations of quantum mechanics.<br />
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简而言之,双方共享的态的纠缠是必要的,但不足以使该态成为非局域态。重要的是要认识到纠缠通常被看作是一个代数概念,因为它是非定域性以及量子遥传和超密编码的先决条件,而非定域性是根据实验统计数据定义的,更多地涉及到基础和量子力学诠释。<br />
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=== Hidden variables theory ===<br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables".<ref>{{Cite news|url=https://www.scientificamerican.com/article/cosmic-test-bolsters-einsteins-ldquo-spooky-action-at-a-distance-rdquo/?WT.mc_id=SA_FB_PHYS_NEWS|title=Cosmic Test Bolsters Einstein's "Spooky Action at a Distance"|last=magazine|first=Elizabeth Gibney, Nature|newspaper=Scientific American|language=en|access-date=2017-02-04}}</ref> The state of the particles being measured contains some [[hidden-variable theory|hidden variables]], whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of quantum mechanics, including familiarity with the formalism and theoretical framework developed in the articles: bra–ket notation and mathematical formulation of quantum mechanics.<br />
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下面的小节适合那些对量子力学的形式和数学描述有良好工作知识的人,包括对文章中开发的形式主义和理论框架的熟悉: bra-ket 符号和量子力学的数学表述。<br />
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=== Violations of Bell's inequality ===<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the [[local realism|local realist]] or hidden variables view were correct, the results would always satisfy [[Bell's inequality]]. A [[Bell test experiments|number of experiments]] have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists.<ref>{{citation |author1=I. Gerhardt |author2=Q. Liu |author3=A. Lamas-Linares |author4=J. Skaar |author5=V. Scarani |author6=V. Makarov |author7=C. Kurtsiefer |year=2011 |title=Experimentally faking the violation of Bell's inequalities |journal=Phys. Rev. Lett. |volume=107 |issue=17 |page=170404 |arxiv=1106.3224 |doi=10.1103/PhysRevLett.107.170404 |bibcode=2011PhRvL.107q0404G |pmid=22107491|s2cid=16306493 }}</ref><ref>{{cite journal | last1 = Santos | first1 = E | year = 2004 | title = The failure to perform a loophole-free test of Bell's Inequality supports local realism | url = | journal = Foundations of Physics | volume = 34 | issue = 11| pages = 1643–1673 | doi=10.1007/s10701-004-1308-z|bibcode = 2004FoPh...34.1643S | s2cid = 123642560 }}</ref> When measurements of the entangled particles are made in moving [[special relativity|relativistic]] reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<ref>{{cite journal |author = H. Zbinden |title = Experimental test of nonlocal quantum correlations in relativistic configurations |journal = Phys. Rev. A |volume = 63 |issue = 2 |pages = 22111 |doi = 10.1103/PhysRevA.63.022111|year = 2001|arxiv = quant-ph/0007009 |bibcode = 2001PhRvA..63b2111Z |display-authors = 1 |last2 = Gisin |last3 = Tittel |s2cid = 44611890 |url = http://archive-ouverte.unige.ch/unige:37034 }}</ref><ref name=LG>Some of the history of both referenced Zbinden, et al. experiments is provided in Gilder, L., ''The Age of Entanglement'', Vintage Books, 2008, pp. 321–324.</ref><br />
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Consider two arbitrary quantum systems and , with respective Hilbert spaces and . The Hilbert space of the composite system is the tensor product<br />
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考虑两个任意的量子系统和,分别具有希尔伯特空间和。复合系统的 Hilbert 空间是张量积<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are [[Incompatible observables|incompatible]] in the sense that these measurements' maximum simultaneous precision is constrained by the [[uncertainty principle]]. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations,<ref>{{cite journal|last1=Cirel'son|first1=B. S.|title=Quantum generalizations of Bell's inequality|journal=Letters in Mathematical Physics|volume=4|issue=2|pages=93–100| year=1980|doi=10.1007/BF00417500|bibcode=1980LMaPh...4...93C|s2cid=120680226}}</ref> and thus entanglement is a fundamentally non-classical phenomenon.<br />
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<math> H_A \otimes H_B.</math><br />
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Entanglement is required to preserve the [[Uncertainty principle]], as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态 < math > scriptstyle | psi rangle _ a </math > ,而第二个系统处于状态 < math > scriptstyle | phi rangle _ b </math > ,则复合系统的状态为<br />
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=== Other types of experiments ===<br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time.<ref name="Xiao-song2012">{{cite journal |author=Xiao-song Ma, Stefan Zotter, Johannes Kofler, Rupert Ursin, Thomas Jennewein, Časlav Brukner & Anton Zeilinger |title=Experimental delayed-choice entanglement swapping |journal=Nature Physics |volume=8 |issue=6 |pages=480–485 |date=26 April 2012 |doi=10.1038/nphys2294|arxiv = 1203.4834 |bibcode = 2012NatPh...8..480M |last2=Zotter |last3=Kofler |last4=Ursin |last5=Jennewein |last6=Brukner |last7=Zeilinger |s2cid=119208488 }}</ref><ref>{{cite journal | last1 = Megidish | first1 = E. | last2 = Halevy | first2 = A. | last3 = Shacham | first3 = T. | last4 = Dvir | first4 = T. | last5 = Dovrat | first5 = L. | last6 = Eisenberg | first6 = H. S. | year = 2013 | title = Entanglement Swapping between Photons that have Never Coexisted | url = | journal = Physical Review Letters | volume = 110 | issue = 21| page = 210403| doi=10.1103/physrevlett.110.210403|arxiv = 1209.4191 |bibcode = 2013PhRvL.110u0403M | pmid=23745845| s2cid = 30063749 }}</ref> The authors claimed that this result was achieved by [[Quantum teleportation#Entanglement swapping|entanglement swapping]] between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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<math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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In three independent experiments in 2013 it was shown that [[classical physics|classically communicated]] [[separable state|separable quantum states]] can be used to carry entangled states.<ref>{{cite web|url=http://physicsworld.com/cws/article/news/2013/dec/11/classical-carrier-could-create-entanglement |title=Classical carrier could create entanglement |publisher=physicsworld.com |accessdate=2014-06-14|date=2013-12-11 }}</ref> The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<ref>{{cite web | url=http://hansonlab.tudelft.nl/loophole-free-bell-test/ | title=Loophole-free Bell test &#124; Ronald Hanson | access-date=24 October 2015 | archive-url=https://web.archive.org/web/20180704082456/http://hansonlab.tudelft.nl/loophole-free-bell-test/ | archive-date=4 July 2018 | url-status=dead }}</ref><br />
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States of the composite system that can be represented in this form are called separable states, or product states.<br />
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可以用这种形式表示的复合系统状态称为可分状态或乘积状态。<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<ref>{{Cite journal|url=http://www.nature.com/news/entangled-photons-make-a-picture-from-a-paradox-1.15781|title=Entangled photons make a picture from a paradox|journal=Nature|accessdate=13 October 2014|doi=10.1038/nature.2014.15781|year=2014|last1=Gibney|first1=Elizabeth|s2cid=124976589}}</ref><br />
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Not all states are separable states (and thus product states). Fix a basis <math>\scriptstyle \{|i \rangle_A\}</math> for and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for . The most general state in is of the form<br />
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并非所有状态都是可分状态(因此也就是乘积状态)。修复一个基础 < math > scriptstyle { | i rangle _ a } </math > for 和一个基础 < math > scriptstyle { | j rangle _ b } </math > for。最普遍的状态是形式<br />
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<br />
In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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<math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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[数学] | psi rangle { AB } = sum { i,j } c { ij } | i rangle _ a otimes | j rangle _ b </math > 。<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<ref>{{Cite journal|last=Rozatkar|first=Gaurav|date=2018-08-16|title=Demonstration of quantum entanglement|url=https://osf.io/g8bpj/|journal=OSF|language=en}}</ref><br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > ,那么这种状态是可分的,因此 < math scriptstyle c { ij } = c ^ a _ ic ^ b _ j,</math > 产生 < math scriptstyle | psi rangle _ a = sum { i } c ^ a _ { i } | i } | i _ a </math > 和 < math > phi scriptstyle | b = sum { j } | j } | j rangle b = sum { j }。如果对于任何向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > 至少对于一对坐标 < math > scriptstyle c ^ a _ i,c ^ b _ j </math > 我们有 < math > scriptstyle c _ { ij } neq c ^ a _ ic ^ b _ j。如果一种状态是不可分割的,那么它被称为“纠缠态”。<br />
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=== Mystery of time ===<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of , the following is an entangled state:<br />
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例如,给定两个基向量{ | 0 rangle _ a,| 1 rangle _ a } </math > 和两个基向量{ | 0 rangle _ b,| 1 rangle _ b } </math > ,下面是一个纠缠态:<br />
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There have been suggestions to look at the concept of time as an [[emergent phenomenon]] that is a side effect of quantum entanglement.<ref>{{Cite journal|title= Time from quantum entanglement: an experimental illustration|arxiv=1310.4691|bibcode = 2014PhRvA..89e2122M |doi = 10.1103/PhysRevA.89.052122|volume=89|issue= 5|pages=052122|journal=Physical Review A|year=2014 | last1 = Moreva | first1 = Ekaterina|s2cid=118638346}}</ref><ref>{{cite web|url=https://www.newscientist.com/article/dn24473-entangled-toy-universe-shows-time-may-be-an-illusion.html#.U8_-ApSSx2A|title=Entangled toy universe shows time may be an illusion|publisher=|accessdate=13 October 2014}}</ref><br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by [[Don Page (physicist)|Don Page]] and [[William Wootters]] in 1983.<ref>David Deutsch, The Beginning of infinity. Page 299</ref><br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right)<br />
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The [[Wheeler–DeWitt equation]] that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<ref name="medium.com">{{cite web|url=https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933|title=Quantum Experiment Shows How Time 'Emerges' from Entanglement|website=Medium|accessdate=13 October 2014|date=2013-10-23}}</ref><br />
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If the composite system is in this state, it is impossible to attribute to either system or system a definite pure state. Another way to say this is that while the von Neumann entropy of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry. The above example is one of four Bell states, which are (maximally) entangled pure states (pure states of the space, but which cannot be separated into pure states of each and ).<br />
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如果组合系统处于这种状态,就不可能给任何一个系统或系统一个确定的纯状态。另一种说法是,尽管整个状态的冯纽曼熵为零(对于任何纯状态都是如此) ,但子系统的熵大于零。从这个意义上说,这两个系统是“纠缠”的。这对干涉测量法有具体的经验影响。上面的例子是四个贝尔态之一,它们是(最大)纠缠纯态(空间的纯态,但不能分离成每个和的纯态)。<br />
<br />
In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted{{by whom|date=August 2020}} to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts.<ref name="medium.com"/><br />
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Now suppose Alice is an observer for system , and Bob is an observer for system . If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of , there are two possible outcomes, occurring with equal probability:<br />
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现在假设 Alice 是系统的观察者,而 Bob 是系统的观察者。如果在上面给出的纠缠态中,爱丽丝在[ | 0 rangle,| 1 rangle ] </math 本征基中进行测量,有两种可能的结果,发生的概率相等:<br />
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=== Source for the arrow of time ===<br />
<br />
Physicist [[Seth Lloyd]] says that [[quantum uncertainty]] gives rise to entanglement, the putative source of the [[arrow of time]]. According to Lloyd; "The arrow of time is an arrow of increasing correlations."<ref>{{Cite journal|url=https://www.wired.com/2014/04/quantum-theory-flow-time/|title=New Quantum Theory Could Explain the Flow of Time|journal=Wired|accessdate=13 October 2014|date=2014-04-25|last1=Wolchover|first1=Natalie}}</ref> The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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Alice 测量0,系统的状态崩溃为 < math > scriptstyle | 0 rangle _ a | 1 rangle _ b </math > 。<br />
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Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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Alice 测量1,系统的状态崩溃为 < math > scriptstyle | 1 rangle _ a | 0 rangle _ b </math > 。<br />
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=== Emergent gravity ===<br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system has been altered by Alice performing a local measurement on system . This remains true even if the systems and are spatially separated. This is the foundation of the EPR paradox.<br />
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如果前者发生,那么 Bob 在相同基础上执行的任何后续测量都将返回1。如果出现后一种情况,(Alice 度量1) ,那么 Bob 的度量将确定返回0。因此,Alice 对系统进行了本地测量,从而对系统进行了更改。即使系统和空间上是分开的,这也是正确的。这就是 EPR 悖论的基础。<br />
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Based on [[AdS/CFT correspondence]], [[Mark Van Raamsdonk]] suggested that [[spacetime]] arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time.<ref>{{Cite journal|last=Van Raamsdonk|first=Mark|date=2010-06-19|title=Building up spacetime with quantum entanglement|journal=General Relativity and Gravitation|language=en|volume=42|issue=10|pages=2323–2329|doi=10.1007/s10714-010-1034-0|issn=0001-7701|arxiv=1005.3035|bibcode=2010GReGr..42.2323V}}</ref> [[Induced gravity]] can emerge from the entanglement first law.<ref>{{Cite journal|last1=Lee|first1=Jae-Weon|last2=Kim|first2=Hyeong-Chan|last3=Lee|first3=Jungjai|date=2013|title=Gravity from quantum information|journal=Journal of the Korean Physical Society|language=en|volume=63|issue=5|pages=1094–1098|doi=10.3938/jkps.63.1094|issn=0374-4884|arxiv=1001.5445|bibcode=2013JKPS...63.1094L|s2cid=118494859}}</ref><ref>{{cite arxiv|last1=Swingle|first1=Brian|last2=Van Raamsdonk|first2=Mark|date=2014-05-12|title=Universality of Gravity from Entanglement|eprint=1405.2933 |class=hep-th}}</ref><br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem.<br />
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爱丽丝的测量结果是随机的。Alice 不能决定将组合系统折叠到哪个状态,因此不能通过作用于她的系统将信息传递给 Bob。因此,在这个特定的方案中,因果关系被保留了下来。关于一般的论点,请参阅不交流定理。<br />
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== Non-locality and entanglement ==<br />
<br />
In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations.<ref name="Brunner-RMP2014">{{cite journal |title=Bell nonlocality |author1=Nicolas Brunner |author2=Daniel Cavalcanti |author3=Stefano Pironio |author4=Valerio Scarani |author5=Stephanie Wehner |journal=Rev. Mod. Phys. |volume=86 |issue=2 |pages=419–478 |date=2014 |doi=10.1103/RevModPhys.86.419 |arxiv=1303.2849|bibcode=2014RvMP...86..419B |s2cid=119194006 }}</ref> A well-known example is the [[Werner state]]s that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables.<ref name=werner1989>{{cite journal | last = Werner| first = R.F. | title = Quantum States with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model | journal = [[Physical Review A]] | volume = 40| pages = 4277–4281 | year = 1989 |doi=10.1103/PhysRevA.40.4277 | pmid=9902666 | issue=8|bibcode = 1989PhRvA..40.4277W }}</ref> Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<ref>{{cite journal|author=R. Augusiak, M. Demianowicz, J. Tura and A. Acín |title=Entanglement and Nonlocality are Inequivalent for Any Number of Parties |journal=Phys. Rev. Lett. |volume=115 |issue=3 |pages=030404 |year=2015 |arxiv=1407.3114 |doi=10.1103/PhysRevLett.115.030404|pmid=26230773 |hdl=2117/78836 |bibcode=2015PhRvL.115c0404A |s2cid=29758483 }}</ref><br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all [[entanglement distillation|distillable]] states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<ref>{{cite journal |title=Disproving the Peres conjecture: Bell nonlocality from bipartite bound entanglement |authors=Tamas Vértesi, Nicolas Brunner|year=2014 |journal=Nature Communications |volume=5 |issue=5297|page=5297 |doi=10.1038/ncomms6297 |pmid=25370352|arxiv=1405.4502 |s2cid=5135148}}</ref><br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a density matrix, which is a positive-semidefinite matrix, or a trace class when the state space is infinite-dimensional, and has trace 1. Again, by the spectral theorem, such a matrix takes the general form:<br />
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如上所述,量子系统的状态是由希尔伯特空间中的单位向量给出的。更一般地说,如果一个人对系统的了解较少,那么他就称之为“集合” ,并用密度矩阵来描述它,密度矩阵是正半定矩阵,或者当状态空间是无限维且迹1时,用迹类来描述它。同样的,在谱定理,这样的矩阵采取了一般的形式:<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to [[quantum teleportation]] and to [[superdense coding]], whereas non-locality is defined according to experimental statistics and is much more involved with the [[Quantum foundations|foundations]] and [[interpretations of quantum mechanics]].<ref>In the literature "non-locality" is sometimes used to characterize concepts that differ from the non-existence of a local hidden variable model, e.g., whether states can be distinguished by local measurements and which can occur also for non-entangled states (see, e.g., {{cite journal |authors=Charles H. Bennett, David P. DiVincenzo, Christopher A. Fuchs, Tal Mor, Eric Rains, Peter W. Shor, John A. Smolin, and William K. Wootters |title=Quantum nonlocality without entanglement |journal=Phys. Rev. A |volume=59 |issue=2 |pages=1070–1091 |year=1999 |doi=10.1103/PhysRevA.59.1070 |arxiv= quant-ph/9804053|bibcode=1999PhRvA..59.1070B |s2cid=15282650 }}). This non-standard use of the term is not discussed here.</ref><br />
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<math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
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我不知道,我不知道,我不知道<br />
<br />
<br />
<br />
== Quantum mechanical framework ==<br />
<br />
where the w<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret as representing an ensemble where is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need density matrices to represent the state.<br />
<br />
其中 w < sub > i </sub > 是正值概率(和为1) ,向量是单位向量,在无限维情况下,我们取这些状态的闭包为迹范数。我们可以解释为代表一个集合,其中集合的状态是 < math > | alpha _ i rangle </math > 。当一个混合状态的秩为1时,它就描述了一个纯系综。当量子系统的状态信息少于总量时,我们需要密度矩阵来表示状态。<br />
<br />
The following subsections are for those with a good working knowledge of the formal, mathematical description of [[quantum mechanics]], including familiarity with the formalism and theoretical framework developed in the articles: [[bra–ket notation]] and [[mathematical formulation of quantum mechanics]].<br />
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<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits electrons towards an observer. The electrons' Hilbert spaces are identical. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with spins aligned in the positive direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
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在实验上,可以实现如下的混合集成。考虑一个“黑盒子”装置,它向观察者喷射电子。电子的希尔伯特空间是相同的。该装置可能产生全部处于相同状态的电子; 在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以在不同的状态下产生电子。例如,它可以产生两个电子群: 一个是状态 < math > | mathbf { z } + rangle </math > 的正方向自旋,另一个是状态 < math > | mathbf { y }-rangle </math > 的负方向自旋。通常,这是一个混合集合,因为可以有任意数量的总体,每个总体对应不同的状态。<br />
<br />
=== Pure states ===<br />
<br />
Consider two arbitrary quantum systems {{mvar|A}} and {{mvar|B}}, with respective [[Hilbert space]]s {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}. The Hilbert space of the composite system is the [[tensor product]]<br />
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Following the definition above, for a bipartite composite system, mixed states are just density matrices on . That is, it has the general form<br />
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根据上面的定义,对于二部复合系统,混合态仅仅是上面的密度矩阵。也就是说,它有一般的形式<br />
<br />
<br />
<br />
: <math> H_A \otimes H_B.</math><br />
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<math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
[数学] rho = sum { i } w _ i 左[ sum _ { j } bar { c }{ ij }(| alpha _ { ij } rangle otimes | beta _ { ij } rangle)右]左[ sum _ k c _ { ik }(langle alpha _ ik } | otimes langle beta _ { ik } | 右]<br />
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</math><br />
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数学<br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
<br />
<br />
<br />
where the w<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
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其中 w < sub > i </sub > 是正值概率,< math > sum _ j | c _ { ij } | ^ 2 = 1 </math > ,向量是单位向量。这是自伴和正的,并且有迹1。<br />
<br />
: <math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<br />
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从纯粹情形扩展可分性的定义,我们说混合状态是可分的,如果它可以写成<br />
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States of the composite system that can be represented in this form are called [[separable state]]s, or [[product state]]s.<br />
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<br />
<br />
<math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
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(数学) rho = sum i w i rho i ^ a times rho i ^ b,(数学)<br />
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Not all states are separable states (and thus product states). Fix a [[basis (linear algebra)|basis]] <math>\scriptstyle \{|i \rangle_A\}</math> for {{mvar|H<sub>A</sub>}} and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for {{mvar|H<sub>B</sub>}}. The most general state in {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} is of the form<br />
<br />
<br />
<br />
where the are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems and respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
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其中的正值概率和 rho _ i ^ a </math > 的和 rho _ i ^ b </math > 的本身是子系统和子系统上的混合状态(密度算符)。换句话说,如果一个状态是不相关状态或乘积状态上的概率分布,则该状态是可分的。通过将密度矩阵写成纯系综和并进行扩展,我们可以假定,不失一般性和数学本身就是纯系综。如果一个状态不可分离,则称其为纠缠态。<br />
<br />
: <math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be NP-hard. For the and cases, a necessary and sufficient criterion for separability is given by the famous Positive Partial Transpose (PPT) condition.<br />
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一般来说,要判断一个混合态是否是纠缠态是很困难的。一般的二部格被证明是 np 困难的。对于和种情形,利用著名的正偏转子(PPT)条件给出了可分性的一个充要条件。<br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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<br />
<br />
For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of {{mvar|H<sub>A</sub>}} and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of {{mvar|H<sub>B</sub>}}, the following is an entangled state:<br />
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The idea of a reduced density matrix was introduced by Paul Dirac in 1930. Consider as above systems and each with a Hilbert space . Let the state of the composite system be<br />
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约化密度矩阵的概念是由保罗 · 狄拉克在1930年提出的。考虑以上系统,每个系统都有一个希尔伯特空间。设复合系统的状态为<br />
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<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
<br />
<math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
[数学] | Psi 在 h _ a 和 h _ b 之间。数学<br />
<br />
<br />
<br />
If the composite system is in this state, it is impossible to attribute to either system {{mvar|A}} or system {{mvar|B}} a definite [[pure state]]. Another way to say this is that while the [[von Neumann entropy]] of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry.<ref name="JaegerEtAl95">{{cite journal |author=Jaeger G, Shimony A, Vaidman L |title=Two Interferometric Complementarities |journal=Phys. Rev. |volume=51 |issue=1 |pages=54–67 |year=1995 |doi=10.1103/PhysRevA.51.54|pmid=9911555 |bibcode = 1995PhRvA..51...54J |last2=Shimony |last3=Vaidman }}</ref> The above example is one of four [[Bell states]], which are (maximally) entangled pure states (pure states of the {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} space, but which cannot be separated into pure states of each {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}).<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system . However, it still is possible to associate a density matrix. Let<br />
<br />
如上所述,通常没有办法将纯状态关联到组件系统。然而,仍然有可能将密度矩阵联系起来。让<br />
<br />
<br />
<br />
Now suppose Alice is an observer for system {{mvar|A}}, and Bob is an observer for system {{mvar|B}}. If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of {{mvar|A}}, there are two possible outcomes, occurring with equal probability:<ref name=nielchuang>{{cite book| last = Nielsen | first = Michael A. |author2=Chuang, Isaac L. | year = 2000 | title = Quantum Computation and Quantum Information | publisher = [[Cambridge University Press]] | pages = 112–113| isbn = 978-0-521-63503-5}}</ref><br />
<br />
<math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
我不知道,我不知道,我不知道。<br />
<br />
<br />
<br />
# Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
<br />
which is the projection operator onto this state. The state of is the partial trace of over the basis of system :<br />
<br />
也就是这个状态的投影操作符。状态是系统基础上的部分轨迹:<br />
<br />
# Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
<br />
<br />
<br />
<math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
(| Psi rangle langle Psi | right) | j rangle b = hbox { Tr } _ b; rho _ t. </math > <br />
<br />
If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system {{mvar|B}} has been altered by Alice performing a local measurement on system {{mvar|A}}. This remains true even if the systems {{mvar|A}} and {{mvar|B}} are spatially separated. This is the foundation of the [[EPR paradox]].<br />
<br />
<br />
<br />
is sometimes called the reduced density matrix of on subsystem . Colloquially, we "trace out" system to obtain the reduced density matrix on .<br />
<br />
有时被称为子系统的约化密度矩阵。通俗地说,我们“追踪”系统,以获得约化密度矩阵。<br />
<br />
The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see [[no-communication theorem]].<br />
<br />
<br />
<br />
For example, the reduced density matrix of for the entangled state<br />
<br />
例如,纠缠态的约化密度矩阵<br />
<br />
=== Ensembles ===<br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a [[density matrix]], which is a [[positive-semidefinite matrix]], or a [[trace class]] when the state space is infinite-dimensional, and has trace 1. Again, by the [[spectral theorem]], such a matrix takes the general form:<br />
<br />
<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right) ,</math > <br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
discussed above is<br />
<br />
以上所讨论的是<br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors {{mvar| α<sub>i</sub>}} are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret {{mvar|ρ}} as representing an ensemble where {{mvar|w<sub>i</sub>}} is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need [[#Reduced density matrices|density matrices]] to represent the state.<br />
<br />
<math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
左(| 0 rangle 0 | a + | 1 rangle 1 | a right) </math > <br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits [[electron]]s towards an observer. The electrons' Hilbert spaces are [[identical particles|identical]]. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with [[spin (physics)|spins]] aligned in the positive {{math|'''z'''}} direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative {{math|'''y'''}} direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
这表明,正如预期的那样,一个纠缠纯系综的约化密度矩阵是一个混合系综。同样不足为奇的是,上面讨论的纯乘积态的密度矩阵<br />
<br />
<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}}. That is, it has the general form<br />
<br />
<math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
我不知道,但是我知道,我知道。<br />
<br />
<br />
<br />
: <math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
一般情况下,二体纯态 ρ 纠缠当且仅当其约化态是混合态而不是纯态。<br />
<br />
</math><br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional AKLT spin chain: the ground state can be divided into a block and an environment. The reduced density matrix of the block is proportional to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
在不同的基态自旋链中显式计算了约化密度矩阵。一维 AKLT 自旋链就是一个例子: 基态可以分为一个区块和一个环境。块的约化密度矩阵与另一个哈密顿量的简并基态成正比。<br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<ref name=Laloe>{{citation|last=Laloe|first=Franck|year=2001|title=Do We Really Understand Quantum Mechanics|journal=American Journal of Physics |volume=69 |issue=6|pages=655–701 |arxiv=quant-ph/0209123 |bibcode=2001AmJPh..69..655L |doi=10.1119/1.1356698}}</ref>{{rp|131–132}}<br />
<br />
The reduced density matrix also was evaluated for XY spin chains, where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence in this case.<br />
<br />
并对 XY 自旋链的全秩约化密度矩阵进行了计算。证明了在热力学极限中,大块自旋的约化密度矩阵的谱在这种情况下是一个精确的几何序列。<br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary quantum operations can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called LOCC (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<br />
<br />
在量子信息理论中,纠缠态被认为是一种“资源” ,即制造成本高昂的物质,并且可以实现有价值的转换。这种观点最为明显的背景是“遥远的实验室” ,即两个标记为“ a”和“ b”的量子系统,其中每个系统都可以执行任意的量子操作,但它们之间不存在量子力学相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为 LOCC 的操作(局部操作和经典通信)。这些操作不允许在系统 a 和系统 b 之间产生纠缠态。但是如果给 a 和 b 提供了纠缠态,那么这些纠缠态和 LOCC 操作一起可以产生更大类的变换。例如,a 的一个量子比特和 b 的一个量子比特之间的相互作用可以通过首先将 a 的量子比特传送到 b,然后让 b 的量子比特和 b 的量子比特相互作用(这现在是一个 LOCC 操作,因为两个量子比特都在 b 的实验室里) ,然后再传送量子比特回到 a。两个量子比特的最大纠缠态在这个过程中被用完。因此,纠缠态是一种资源,它能够在只有 LOCC 可用的情况下实现量子相互作用(或量子通道) ,但是在这个过程中会被消耗掉。在其他应用中,纠缠态可以被看作是一种资源,例如,私人通信或者区分量子态。<br />
<br />
where the {{mvar|w<sub>i</sub>}} are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems {{mvar|A}} and {{mvar|B}} respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be [[NP-hard]].<ref>{{Cite book |author=Gurvits L |title=Proceedings of the thirty-fifth ACM symposium on Theory of computing - STOC '03 |chapter=Classical deterministic complexity of Edmonds' Problem and quantum entanglement |journal=Proceedings of the Thirty-fifth Annual ACM Symposium on Theory of Computing |year=2003 |doi=10.1145/780542.780545 |page=10 |isbn=978-1-58113-674-6|arxiv=quant-ph/0303055 |s2cid=5745067 }}</ref> For the {{math|2 × 2}} and {{math|2 × 3}} cases, a necessary and sufficient criterion for separability is given by the famous [[Peres-Horodecki criterion|Positive Partial Transpose (PPT)]] condition.<ref>{{cite journal |author=Horodecki M, Horodecki P, Horodecki R |title=Separability of mixed states: necessary and sufficient conditions |journal=Physics Letters A |volume=223 |issue=1 |page=210 |year=1996 |doi=10.1016/S0375-9601(96)00706-2 |bibcode=1996PhLA..223....1H|arxiv = quant-ph/9605038 |last2=Horodecki |last3=Horodecki |citeseerx=10.1.1.252.496 |s2cid=10580997 }}</ref><br />
<br />
<br />
<br />
=== Reduced density matrices ===<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
<br />
在这一节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的度量。<br />
<br />
The idea of a reduced density matrix was introduced by [[Paul Dirac]] in 1930.<ref>{{cite journal|doi=10.1017/S0305004100016108|title=Note on Exchange Phenomena in the Thomas Atom|year=2008|last1=Dirac|first1=P. A. M.|journal=Mathematical Proceedings of the Cambridge Philosophical Society| volume=26| issue=3|page=376|bibcode=1930PCPS...26..376D|url=https://www.cambridge.org/core/services/aop-cambridge-core/content/view/6C5FF7297CD96F49A8B8E9E3EA50E412/S0305004100016108a.pdf/div-class-title-note-on-exchange-phenomena-in-the-thomas-atom-div.pdf}}</ref> Consider as above systems {{mvar|A}} and {{mvar|B}} each with a Hilbert space {{mvar|H<sub>A</sub>, H<sub>B</sub>}}. Let the state of the composite system be<br />
<br />
<br />
<br />
: <math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.<br />
<br />
二分子2能级纯态的冯纽曼熵与本征值的图。当本征值为5时,冯纽曼熵处于最大值,相当于最大纠缠度。<br />
<br />
<br />
<br />
In classical information theory , the Shannon entropy, is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<br />
<br />
在经典的信息论中,香农熵,是与概率分布相关联的,如下:<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system {{mvar|A}}. However, it still is possible to associate a density matrix. Let<br />
<br />
<br />
<br />
<math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
<br />
[ math ] h (p _ 1,cdots,p _ n) =-sum _ i p _ i log _ 2 p _ i. [ math ]<br />
<br />
: <math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
<br />
<br />
Since a mixed state is a probability distribution over an ensemble, this leads naturally to the definition of the von Neumann entropy:<br />
<br />
由于混合状态是一个概率分布超过一个总体,这自然导致了冯纽曼熵的定义:<br />
<br />
which is the [[projection operator]] onto this state. The state of {{mvar|A}} is the [[partial trace]] of {{mvar|ρ<sub>T</sub>}} over the basis of system {{mvar|B}}:<br />
<br />
<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
<br />
(rho) =-hbox { Tr } left (rho log _ 2{ rho } right) <br />
<br />
: <math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
<br />
<br />
In general, one uses the Borel functional calculus to calculate a non-polynomial function such as . If the nonnegative operator acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
<br />
一般来说,人们使用 Borel 函数演算来计算一个非多项式函数,如。如果非负算子作用于有限维希尔伯特空间,并且具有本征值 < math > lambda _ 1,那么 cdots,lambda _ n </math > ,结果只不过是具有相同本征向量的算子,但本征值 < math > log _ 2(lambda _ 1) ,点,log _ 2(lambda _ n) </math > 。那么香农熵就是:<br />
<br />
{{mvar|ρ<sub>A</sub>}} is sometimes called the reduced density matrix of {{mvar|ρ}} on subsystem {{mvar|A}}. Colloquially, we "trace out" system {{mvar|B}} to obtain the reduced density matrix on {{mvar|A}}.<br />
<br />
<br />
<br />
<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
<br />
(rho) =-hbox { Tr } left (rho log 2{ rho } right) =-sum _ i lambda _ i log _ 2 lambda _ i </math > .<br />
<br />
For example, the reduced density matrix of {{mvar|A}} for the entangled state<br />
<br />
<br />
<br />
Since an event of probability 0 should not contribute to the entropy, and given that<br />
<br />
因为一个概率为0的事件不应该对熵有贡献,并且假设<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
<br />
<br />
<math> \lim_{p \to 0} p \log p = 0,</math><br />
<br />
[ math > lim _ { p to 0} p log p = 0,</math > <br />
<br />
discussed above is<br />
<br />
<br />
<br />
the convention 0}} is adopted. This extends to the infinite-dimensional case as well: if has spectral resolution<br />
<br />
约定0}被采用。这也延伸到无限维情况: 如果有光谱分辨率<br />
<br />
: <math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
<br />
<br />
<math> \rho = \int \lambda d P_{\lambda},</math><br />
<br />
数学,数学,数学<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of {{mvar|A}} for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
<br />
<br />
assume the same convention when calculating<br />
<br />
在计算时采用相同的约定<br />
<br />
: <math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
<br />
<br />
<math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
<br />
[数学] rho log 2 rho = int lambda log 2 lambda d { lambda }<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
<br />
<br />
As in statistical mechanics, the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is (which can be shown to be the maximum entropy for mixed states).<br />
<br />
就像统计力学一样,系统的不确定性(微观状态的数量)越多,熵就越大。例如,任何纯态的熵都为零,这并不奇怪,因为处于纯态的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个的熵都是(混合态的最大熵)。<br />
<br />
=== Two applications that use them ===<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional [[AKLT Model|AKLT spin chain]]:<ref name="Fan2004">{{cite journal | doi = 10.1103/PhysRevLett.93.227203 | title = Entanglement in a Valence-Bond Solid State | journal = Physical Review Letters | year = 2004 | first = H | last = Fan | page = 227203 |author2=Korepin V |author3=Roychowdhury V | volume = 93 | issue = 22 | pmid = 15601113 |arxiv=quant-ph/0406067 | bibcode=2004PhRvL..93v7203F| s2cid = 28587190 }}</ref> the ground state can be divided into a block and an environment. The reduced density matrix of the block is [[Proportionality (mathematics)|proportional]] to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist. If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
<br />
熵提供了一个可以用来量化纠缠的工具,尽管还存在其他的纠缠度量方法。如果整个系统是纯系统,则可以用一个子系统的熵来衡量其与其他子系统的纠缠程度。<br />
<br />
The reduced density matrix also was evaluated for [[Heisenberg model (quantum)|XY spin chains]], where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence<ref>{{cite journal| doi=10.1007/s11128-010-0197-7|arxiv=1002.2931|title=Spectrum of the density matrix of a large ''block of'' spins of the XY model in one dimension| year=2010|last1=Franchini|first1=F.|last2=Its|first2=A. R.|last3=Korepin|first3=V. E.|last4=Takhtajan|first4=L. A.|journal=Quantum Information Processing|volume=10|issue=3|pages=325–341|s2cid=6683370}}</ref> in this case.<br />
<br />
<br />
<br />
For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
<br />
对于两体纯态,减少态的冯纽曼熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的特定公理的态家族中唯一的函数。<br />
<br />
=== Entanglement as a resource ===<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary [[quantum operation]]s can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called [[LOCC]] (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<ref name="horodecki2007" /><br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/n,...,1/n}. Therefore, a bipartite pure state is said to be a maximally entangled state if the reduced state of is the diagonal matrix<br />
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一个经典的结果是,香农熵在均匀概率分布{1/n,... ,1/n }处达到最大值。因此,如果二分纯态的约化态是对角矩阵,则称二分纯态为最大纠缠态<br />
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=== Classification of entanglement ===<br />
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<math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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< math > begin { bmatrix } frac {1}{ n } & & ddots & frac {1}{ n } end { bmatrix } . </math > <br />
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Not all quantum states are equally valuable as a resource. To quantify this value, different [[Quantum entanglement#Entanglement measures|entanglement measures]] (see below) can be used, that assign a numerical value to each quantum state. However, it is often interesting to settle for a coarser way to compare quantum states. This gives rise to different classification schemes. Most entanglement classes are defined based on whether states can be converted to other states using LOCC or a subclass of these operations. The smaller the set of allowed operations, the finer the classification. Important examples are:<br />
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* If two states can be transformed into each other by a local unitary operation, they are said to be in the same ''LU class''. This is the finest of the usually considered classes. Two states in the same LU class have the same value for entanglement measures and the same value as a resource in the distant-labs setting. There is an infinite number of different LU classes (even in the simplest case of two qubits in a pure state).<ref name="GRB1998">>{{cite journal |author1=Grassl, M. |author2=Rötteler, M. |author3=Beth, T. |title=Computing local invariants of quantum-bit systems |journal=Phys. Rev. A |volume=58 |issue=3 |pages=1833–1839 |year=1998 |doi=10.1103/PhysRevA.58.1833 |arxiv=quant-ph/9712040|bibcode=1998PhRvA..58.1833G |s2cid=15892529 }}</ref><ref name="Kraus2010">{{cite journal |author=B. Kraus |authorlink=Barbara Kraus|title=Local unitary equivalence of multipartite pure states |journal=Phys. Rev. Lett. |volume=104 |issue=2 |page=020504 |year=2010 |arxiv=0909.5152 |doi=10.1103/PhysRevLett.104.020504|pmid=20366579 |bibcode=2010PhRvL.104b0504K|s2cid=29984499}}</ref><br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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对于混合态,简化冯纽曼熵并不是唯一合理的纠缠度量。<br />
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* If two states can be transformed into each other by local operations including measurements with probability larger than 0, they are said to be in the same 'SLOCC class' ("stochastic LOCC"). Qualitatively, two states <math>\rho_1</math> and <math>\rho_2</math> in the same SLOCC class are equally powerful (since I can transform one into the other and then do whatever it allows me to do), but since the transformations <math>\rho_1\to\rho_2</math> and <math>\rho_2\to\rho_1</math> may succeed with different probability, they are no longer equally valuable. E.g., for two pure qubits there are only two SLOCC classes: the entangled states (which contains both the (maximally entangled) Bell states and weakly entangled states like <math>|00\rangle+0.01|11\rangle</math>) and the separable ones (i.e., product states like <math>|00\rangle</math>).<ref>{{cite journal |author=M. A. Nielsen |title=Conditions for a Class of Entanglement Transformations |journal=Phys. Rev. Lett. |volume=83 |issue=2 |page=436 |year=1999 |doi=10.1103/PhysRevLett.83.436 |arxiv=quant-ph/9811053|bibcode=1999PhRvL..83..436N |s2cid=17928003 }}</ref><ref name="GoWa2010">{{cite journal |authors=Gour, G. & Wallach, N. R. |title=Classification of Multipartite Entanglement of All Finite Dimensionality |journal=Phys. Rev. Lett. |volume=111 |issue=6 |page=060502 |year=2013 |doi=10.1103/PhysRevLett.111.060502 |pmid=23971544 |arxiv=1304.7259|bibcode=2013PhRvL.111f0502G |s2cid=1570745 }}</ref><br />
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* Instead of considering transformations of single copies of a state (like <math>\rho_1\to\rho_2</math>) one can define classes based on the possibility of multi-copy transformations. E.g., there are examples when <math>\rho_1\to\rho_2</math> is impossible by LOCC, but <math>\rho_1\otimes\rho_1\to\rho_2</math> is possible. A very important (and very coarse) classification is based on the property whether it is possible to transform an arbitrarily large number of copies of a state <math>\rho</math> into at least one pure entangled state. States that have this property are called [[Entanglement distillation|distillable]]. These states are the most useful quantum states since, given enough of them, they can be transformed (with local operations) into any entangled state and hence allow for all possible uses. It came initially as a surprise that not all entangled states are distillable, those that are not are called '[[Bound entanglement|bound entangled]]'.<ref name="HHH97">{{cite journal |author1=Horodecki, M. |author2=Horodecki, P. |author3=Horodecki, R. |title=Mixed-state entanglement and distillation: Is there a ''bound'' entanglement in nature? |journal=Phys. Rev. Lett. |volume=80 |issue=1998 |pages=5239–5242 |year=1998 |arxiv=quant-ph/9801069|doi=10.1103/PhysRevLett.80.5239 |bibcode=1998PhRvL..80.5239H |s2cid=111379972 }}</ref><ref name="horodecki2007" /><br />
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As an aside, the information-theoretic definition is closely related to entropy in the sense of statistical mechanics (comparing the two definitions in the present context, it is customary to set the Boltzmann constant 1}}). For example, by properties of the Borel functional calculus, we see that for any unitary operator ,<br />
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顺便说一句,信息论的定义与统计力学意义上的熵密切相关(比较在当前语境下的两个定义,通常设置波兹曼常数1})。例如,通过 Borel 泛函微积分的性质,我们可以看到,对于任何幺正算符,<br />
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A different entanglement classification is based on what the quantum correlations present in a state allow A and B to do: one distinguishes three subsets of entangled states: (1) the ''[[Quantum nonlocality|non-local]] states'', which produce correlations that cannot be explained by a local hidden variable model and thus violate a Bell inequality, (2) the ''[[Quantum steering|steerable]] states'' that contain sufficient correlations for A to modify ("steer") by local measurements the conditional reduced state of B in such a way, that A can prove to B that the state they possess is indeed entangled, and finally (3) those entangled states that are neither non-local nor steerable. All three sets are non-empty.<ref name="WJD2007">{{cite journal |title=Steering, Entanglement, Nonlocality, and the Einstein-Podolsky-Rosen Paradox |authors=H. M. Wiseman, S. J. Jones, and A. C. Doherty |journal=Phys. Rev. Lett. |volume=98 |issue=14 |page=140402 |year=2007 |doi=10.1103/PhysRevLett.98.140402 |pmid=17501251 |arxiv=quant-ph/0612147|bibcode=2007PhRvL..98n0402W |s2cid=30078867 }}</ref><br />
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<math>S(\rho) = S \left (U \rho U^* \right).</math><br />
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s (rho) = s left (u rho u ^ * right) . </math > <br />
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=== Entropy ===<br />
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Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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事实上,如果没有这个属性,冯纽曼熵就不会有明确的定义。<br />
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In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
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In particular, could be the time evolution operator of the system, i.e.,<br />
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特别是,可以是系统的时间演化算子,即,<br />
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==== Definition ====<br />
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[[File:Von Neumann entropy for bipartite system plot.svg|right|thumb|200px|The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.]]<br />
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<math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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[ math ] u (t) = exp left (frac {-i h t }{ hbar } right) ,[ math ]<br />
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In classical [[information theory]] {{mvar|H}}, the [[Shannon entropy]], is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<ref name="SE">{{cite web |url=http://authors.library.caltech.edu/5516/1/CERpra97b.pdf#page=10 |title=Information-theoretic interpretation of quantum error-correcting codes |first1=Nicolas J. |last1=Cerf |first2=Richard |last2=Cleve }}</ref><br />
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where is the Hamiltonian of the system. Here the entropy is unchanged.<br />
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这个系统的哈密顿量在哪里。这里熵不变。<br />
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: <math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the arrow of time towards thermodynamic equilibrium is simply the growing spread of quantum entanglement.<br />
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一个过程的可逆性与由此产生的熵变有关,也就是说,一个过程是可逆的,当且仅当它使系统的熵不变。因此,时间之箭向热力学平衡的前进只不过是量子纠缠的蔓延。<br />
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Since a mixed state {{mvar|ρ}} is a probability distribution over an ensemble, this leads naturally to the definition of the [[von Neumann entropy]]:<br />
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This provides a connection between quantum information theory and thermodynamics.<br />
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这提供了量子信息理论和热力学之间的联系。<br />
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: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
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Rényi entropy also can be used as a measure of entanglement.<br />
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熵也可以用来度量纠缠。<br />
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In general, one uses the [[Borel functional calculus]] to calculate a non-polynomial function such as {{math|log<sub>2</sub>(''ρ'')}}. If the nonnegative operator {{mvar|ρ}} acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, {{math|log<sub>2</sub>(''ρ'')}} turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
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Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, entanglement entropy is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<br />
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量子纠缠度量了量子态(通常被视为双体)中纠缠的数量。如前所述,纠缠熵是纯态的标准量度(但不再是混合态的量度)。对于混合态,文献中有一些纠缠度量<br />
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: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
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Since an event of probability 0 should not contribute to the entropy, and given that<br />
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The Reeh-Schlieder theorem of quantum field theory is sometimes seen as an analogue of quantum entanglement.<br />
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量子场论的 Reeh-Schlieder 定理有时被看作是量子纠缠的类比。<br />
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:<math> \lim_{p \to 0} p \log p = 0,</math><br />
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the convention {{math|0 log(0) {{=}} 0}} is adopted. This extends to the infinite-dimensional case as well: if {{mvar|ρ}} has [[projection-valued measure|spectral resolution]]<br />
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Entanglement has many applications in quantum information theory. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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纠缠态在量子信息理论中有许多应用。在纠缠的帮助下,否则不可能完成的任务就可能实现。<br />
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: <math> \rho = \int \lambda d P_{\lambda},</math><br />
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Among the best-known applications of entanglement are superdense coding and quantum teleportation.<br />
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其中最著名的应用是超稠密编码和量子遥传纠缠。<br />
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assume the same convention when calculating<br />
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Most researchers believe that entanglement is necessary to realize quantum computing (although this is disputed by some).<br />
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大多数研究人员认为量子纠缠对于实现量子计算是必要的(尽管有些人对此有争议)。<br />
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: <math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
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Entanglement is used in some protocols of quantum cryptography. This is because the "shared noise" of entanglement makes for an excellent one-time pad. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.<br />
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纠缠被用于量子密码学的一些协议中。这是因为纠缠的“共享噪音”造就了绝佳的一次性衬垫。此外,由于测量纠缠对的任何一个成员都会破坏它们共享的纠缠,基于纠缠的量子密码学可以让发送方和接收方更容易地检测到拦截器的存在。<br />
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As in [[entropy|statistical mechanics]], the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is {{math|log(2)}} (which can be shown to be the maximum entropy for {{math|2 × 2}} mixed states).<br />
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In interferometry, entanglement is necessary for surpassing the standard quantum limit and achieving the Heisenberg limit.<br />
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在干涉术中,纠缠态对于超越标准量子极限和达到海森堡极限是必要的。<br />
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==== As a measure of entanglement ====<br />
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Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist.<ref name="arxiv.org">{{cite journal|author1=Plenio|title=An introduction to entanglement measures|year=2007|pages=1–51|volume=1|journal=Quant. Inf. Comp. |arxiv=quant-ph/0504163|bibcode=2005quant.ph..4163P|last2=Virmani}}</ref> If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
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There are several canonical entangled states that appear often in theory and experiments.<br />
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在理论和实验中经常会出现几种典型的纠缠态。<br />
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For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
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For two qubits, the Bell states are<br />
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对于两个量子比特,贝尔态是<br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/''n'',...,1/''n''}. Therefore, a bipartite pure state {{math|''ρ'' ∈ ''H''<sub>A</sub> ⊗ ''H''<sub>B</sub>}} is said to be a '''maximally entangled state''' if the reduced state{{clarify|reason=To which system, A or B, or perhaps both?|date=May 2015}} of {{mvar|ρ}} is the diagonal matrix<br />
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<math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
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< math > | Phi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 0 rangle _ b | 1 rangle _ a o times | 1 rangle _ b) </math > <br />
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<math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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< math > | Psi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 1 rangle _ b pm | 1 rangle _ a o times | 0 rangle _ b) </math > .<br />
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: <math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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These four pure states are all maximally entangled (according to the entropy of entanglement) and form an orthonormal basis (linear algebra) of the Hilbert space of the two qubits. They play a fundamental role in Bell's theorem.<br />
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这四个纯态都是最大纠缠态(根据纠缠熵) ,并且形成了两个量子位的希尔伯特空间的标准正交基(线性代数)。它们在贝尔定理中起着基本的作用。<br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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For M>2 qubits, the GHZ state is<br />
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对于 m > 2量子位,GHZ 态是<br />
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As an aside, the information-theoretic definition is closely related to [[entropy (statistical views)|entropy]] in the sense of statistical mechanics{{Citation needed|date=January 2009}} (comparing the two definitions in the present context, it is customary to set the [[Boltzmann constant]] {{math|''k'' {{=}} 1}}). For example, by properties of the [[Borel functional calculus]], we see that for any [[unitary operator]] {{mvar|U}},<br />
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<math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
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< math > | mathrm { GHZ } rangle = frac { | 0 rangle ^ { otimes m } + | 1 rangle ^ { otimes m }{ sqrt {2} ,</math > <br />
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: <math>S(\rho) = S \left (U \rho U^* \right).</math><br />
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which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to qudits, i.e., systems of d rather than 2 dimensions.<br />
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它缩小到贝尔状态。传统的 GHZ 状态定义为 < math > m = 3 </math > 。GHZ 状态偶尔会扩展到 qudit,即 d 而不是2维系统。<br />
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Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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Also for M>2 qubits, there are spin squeezed states. Spin squeezed states are a class of squeezed coherent states satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled. Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<br />
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对于 m > 2量子位,也存在自旋压缩态。自旋压缩态是一类对自旋测量不确定度满足一定限制的压缩相干态,它必然是纠缠态。自旋压缩态是利用量子纠缠增强精密测量的理想候选态。<br />
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In particular, {{mvar|U}} could be the time evolution operator of the system, i.e.,<br />
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For two bosonic modes, a NOON state is<br />
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对于两个玻色模态,NOON 状态是<br />
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: <math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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<math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
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[数学] | psi _ text { NOON } rangle = frac { | n rangle _ a | 0 rangle _ b + | {0} rangle _ a | { n } rangle _ b }{ sqrt {2} ,,</math > <br />
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where {{mvar|H}} is the [[Hamiltonian (quantum mechanics)|Hamiltonian]] of the system. Here the entropy is unchanged.<br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the N photons are in one mode" and "the N photons are in the other mode".<br />
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这就像贝尔态 < math > | Psi ^ + rangle </math > 除了基函数0和1已经被“ n 个光子处于一种模式”和“ n 个光子处于另一种模式”所取代。<br />
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The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the [[arrow of time]] towards [[thermodynamic equilibrium]] is simply the growing spread of quantum entanglement.<ref>{{cite news |url=https://www.wired.com/2014/04/quantum-theory-flow-time/ |title=New Quantum Theory Could Explain the Flow of Time |last1=Wolchover |first1=Natalie |date=25 April 2014 |website=www.wired.com |publisher=Quanta Magazine |accessdate=27 April 2014}}</ref><br />
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This provides a connection between [[quantum information theory]] and [[thermodynamics]].<br />
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Finally, there also exist twin Fock states for bosonic modes, which can be created by feeding a Fock state into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<br />
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最后,还存在玻色子模式的双 Fock 态,它可以通过将 Fock 态输入到两个导致分束器的臂来产生。它们是 NOON 态的倍数之和,可以用来实现海森堡极限。<br />
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[[Rényi entropy]] also can be used as a measure of entanglement.<br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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对于适当选择的纠缠度量,Bell、 GHZ 和 NOON 态是最大纠缠态,而自旋压缩态和双 Fock 态只是部分纠缠。部分纠缠态通常更容易在实验上准备。<br />
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=== Entanglement measures ===<br />
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Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, [[entropy of entanglement|entanglement entropy]] is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<ref name="arxiv.org" /> and no single one is standard.<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is spontaneous parametric down-conversion to generate a pair of photons entangled in polarisation. Other methods include the use of a fiber coupler to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a quantum dot, the use of the Hong–Ou–Mandel effect, etc., In the earliest tests of Bell's theorem, the entangled particles were generated using atomic cascades.<br />
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纠缠通常是由亚原子粒子间的直接相互作用产生的。这些相互作用可以有多种形式。最常用的方法之一是用自发参量下转换产生一对纠缠在偏振中的光子。其他方法包括使用光纤耦合器来限制和混合光子,量子点中双激子衰变级联发射的光子,Hong-Ou-Mandel 效应的使用等等。在贝尔定理最早的测试中,纠缠粒子是利用原子级联产生的。<br />
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* Entanglement cost<br />
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* [[entanglement distillation|Distillable entanglement]]<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of entanglement swapping. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<br />
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通过使用纠缠交换,也有可能在不直接相互作用的量子系统之间创造纠缠。如果它们的波函数在空间上仅仅重叠,至少是部分重叠,那么它们也可以相互纠缠全同粒子。<br />
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* Entanglement of formation<br />
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* [[quantum relative entropy|Relative entropy of entanglement]]<br />
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* [[Squashed entanglement]]<br />
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* [[Logarithmic negativity]]<br />
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A density matrix ρ is called separable if it can be written as a convex sum of product states, namely<br />
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密度矩阵 ρ 称为可分的,如果它可以写成乘积态的凸和,即<br />
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Most (but not all) of these entanglement measures reduce for pure states to entanglement entropy, and are difficult ([[NP-hard]]) to compute.<ref>{{cite journal|last1=Huang|first1=Yichen|title=Computing quantum discord is NP-complete|journal=New Journal of Physics|date=21 March 2014|volume=16|issue=3|pages=033027|doi=10.1088/1367-2630/16/3/033027|bibcode=2014NJPh...16c3027H|arxiv = 1305.5941 |s2cid=118556793}}</ref><br />
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<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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显示方式{ rho = sum _ j p _ j rho _ j ^ {(a)}次 rho _ j ^ {(b)}} </math > <br />
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=== Quantum field theory ===<br />
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The [[Reeh-Schlieder theorem]] of [[quantum field theory]] is sometimes seen as an analogue of quantum entanglement.<br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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概率为1 ge p _ j ge 0 </math > 。根据定义,如果一个态不可分离,它就是纠缠态。<br />
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<br />
== Applications ==<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple Peres–Horodecki criterion provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes NP-hard when generalized. Other separability criteria include (but not limited to) the range criterion, reduction criterion, and those based on uncertainty relations. See Ref. for a review of separability criteria in discrete variable systems.<br />
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对于2量子比特和2 × 2量子比特-量子特里特系统(分别为2 × 2和2 × 3) ,简单的 Peres-horowitz 准则为分离提供了一个必要和充分的判据,从而无意识地提供了检测纠缠的判据。然而,对于一般情形,该判据仅仅是可分性的必要条件,因为问题一经推广就变成了 np 难问题。其他可分性标准包括(但不限于)范围标准、归约标准和基于不确定关系的标准。参见参考文献。回顾了离散变量系统的可分性准则。<br />
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Entanglement has many applications in [[quantum information theory]]. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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A numerical approach to the problem is suggested by Jon Magne Leinaas, Jan Myrheim and Eirik Ovrum in their paper "Geometrical aspects of entanglement". Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in Peres-Horodecki criterion testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
<br />
Jon Magne Leinaas,Jan Myrheim 和 Eirik Ovrum 在他们的论文“纠缠的几何方面”中提出了一个数值方法来解决这个问题。莱纳斯等。提供一个数值方法,迭代精炼一个估计的可分离状态朝向要测试的目标状态,并检查目标状态是否确实能够到达。该算法的一个实现(包括内置的 peres-horowitz 标准测试)是[ StateSeparator http://phweb.technion.ac.il/~StateSeparator/] web-app。<br />
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Among the best-known applications of entanglement are [[superdense coding]] and [[quantum teleportation]].<ref>{{cite journal |last1=Bouwmeester |first1=Dik |last2=Pan |first2=Jian-Wei|last3=Mattle |first3=Klaus|last4=Eibl |first4=Manfred |last5=Weinfurter |first5=Harald|last6=Zeilinger |first6=Anton|year=1997 |title=Experimental Quantum Teleportation |journal=Nature |volume=390 |issue=6660 |pages=575–579 |name-list-style=amp |url=http://qudev.ethz.ch/content/courses/QSIT06/pdfs/Bouwmeester97.pdf |doi=10.1038/37539|bibcode = 1997Natur.390..575B |arxiv=1901.11004 |s2cid=4422887 }}</ref><br />
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In continuous variable systems, the Peres-Horodecki criterion also applies. Specifically, Simon formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref. for a seemingly different but essentially equivalent approach). It was later found that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators or by using entropic measures.<br />
<br />
在连续变量系统中,Peres-Horodecki 准则也适用。具体地说,Simon 根据正则算符的二阶矩,制定了 Peres-Horodecki 准则的一个特定版本,并表明它对于 < math > 1 oplus1 </math >-mode Gaussian 状态是必要的和充分的。看似不同,但本质上等价的方法)。后来发现,Simon 的条件对于 < math > 1 oplus n </math >-mode Gaussian 状态也是必要和充分的,但是对于 < math > 2 oplus2 </math >-mode Gaussian 状态不再是充分的。Simon 条件可以通过考虑正则算子的高阶矩或者用熵测度来推广。<br />
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Most researchers believe that entanglement is necessary to realize [[quantum computer|quantum computing]] (although this is disputed by some).<ref name="jozsa02">{{cite journal|author1=Richard Jozsa|author2=Noah Linden|doi=10.1098/rspa.2002.1097|title=On the role of entanglement in quantum computational speed-up|year=2002|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=459|issue=2036|pages=2011–2032|arxiv=quant-ph/0201143|bibcode = 2003RSPSA.459.2011J |citeseerx=10.1.1.251.7637|s2cid=15470259}}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite. The $100m Quantum Experiments at Space Scale (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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2016年,中国发射了世界上第一颗量子通信卫星。耗资1亿美元的空间量子实验任务于2016年8月16日当地时间01:40从中国北方的酒泉卫星发射中心空间站发射升空。<br />
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Entanglement is used in some protocols of [[quantum cryptography]].<ref name="ekert91">{{cite journal |doi=10.1103/PhysRevLett.67.661 |title=Quantum cryptography based on Bell's theorem |year=1991 |last1=Ekert |first1=Artur K. |journal=Physical Review Letters |volume=67 |issue=6 |pages=661–663 |pmid=10044956|bibcode = 1991PhRvL..67..661E |s2cid=27683254 |url=http://pdfs.semanticscholar.org/f8dc/c3047eef8da135bca13b926b1e6cf50e7f3a.pdf }}</ref><ref name="horodecki10">{{cite arXiv |eprint=1006.0468|last1=Yin|first1=Juan|title=Contextuality offers device-independent security|last2=Cao|first2=Yuan|last3=Yong|first3=Hai-Lin|last4=Ren|first4=Ji-Gang|last5=Liang|first5=Hao|last6=Liao|first6=Sheng-Kai|last7=Zhou|first7=Fei|last8=Liu|first8=Chang|last9=Wu|first9=Yu-Ping|last10=Pan|first10=Ge-Sheng|last11=Zhang|first11=Qiang|last12=Peng|first12=Cheng-Zhi|last13=Pan|first13=Jian-Wei|class=quant-ph|year=2010}}</ref> This is because the "shared noise" of entanglement makes for an excellent [[one-time pad]]. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.{{citation needed|date=January 2018}}<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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在接下来的两年里,这艘以中国古代哲学家墨子命名的飞船将展示量子化的可行性<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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地球和太空之间的通信,并在前所未有的距离上测试量子纠缠。<br />
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In [[interferometry]], entanglement is necessary for surpassing the [[standard quantum limit]] and achieving the [[Heisenberg limit]].<ref>{{cite journal |last1=Pezze |first1=Luca |last2=Smerzi |first2=Augusto|year=2009 |title=Entanglement, Nonlinear Dynamics, and the Heisenberg Limit |journal=Phys. Rev. Lett. |volume=102 |issue=10 |pages=100401 |name-list-style=amp |doi=10.1103/PhysRevLett.102.100401 |pmid=19392092 |bibcode=2009PhRvL.102j0401P|arxiv = 0711.4840 |s2cid=13095638 }}</ref><br />
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In the June 16, 2017, issue of Science, Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<br />
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在2017年6月16日的《科学》杂志上。在严格的爱因斯坦定域条件下,从墨丘利卫星到 Lijian、云南和 Delingha、 Quinhai 的基地的 CHSH 估值为2.37 ± 0.09,证明了双光子对的存在和对 Bell 不等式的违反,从而提高了数量级通过光纤实验的传输效率。<br />
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=== Entangled states ===<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
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For two [[qubits]], the [[Bell state]]s are<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be calculated only by consideration of electron entanglement.<br />
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多电子原子的电子壳层总是由纠缠电子组成。只有考虑到电子纠缠,才能计算出正确的电离能。<br />
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: <math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
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: <math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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It has been suggested that in the process of photosynthesis, entanglement is involved in the transfer of energy between light-harvesting complexes and photosynthetic reaction centers where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using femtosecond spectroscopy, the coherence of entanglement in the Fenna-Matthews-Olson complex was measured over hundreds of femtoseconds (a relatively long time in this regard) providing support to this theory.<br />
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研究表明,在光合作用过程中,纠缠参与了捕光复合物与光合反应中心之间的能量传递,而光(能)是以化学能的形式获得的。没有这样一个过程,光转化为化学能的有效性就无从解释。利用飞秒光谱技术,我们测量了 Fenna-Matthews-Olson 复合体中纠缠态的相干性,时间长达数百飞秒,为这一理论提供了支持。<br />
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These four pure states are all maximally entangled (according to the [[entropy of entanglement]]) and form an [[orthonormal]] [[basis (linear algebra)]] of the Hilbert space of the two qubits. They play a fundamental role in [[Bell's theorem]].<br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<br />
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然而,关键的后续研究对这些结果的解释提出了质疑,并将报告的电子量子相干特征赋予了发色团中的核动力学。<br />
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For M>2 qubits, the [[Greenberger–Horne–Zeilinger state|GHZ state]] is<br />
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In 2020 researchers reported the quantum entanglement between the motion of a millimetre-sized mechanical oscillator and a disparate distant spin system of a cloud of atoms.<br />
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2020年,研究人员报告了一个毫米大小的机械振荡器的运动和一个原子云的不同距离的自旋系统之间的量子纠缠。<br />
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: <math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
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which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to [[qudit]]s, i.e., systems of ''d'' rather than 2 dimensions.<br />
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In October 2018, physicists reported producing quantum entanglement using living organisms, particularly between photosynthetic molecules within living bacteria and quantized light.<br />
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2018年10月,物理学家报告说,他们利用活体生物制造量子纠缠,特别是利用活体细菌中的光合分子和量子化的光。<br />
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Also for M>2 qubits, there are [[Spin squeezing|spin squeezed states]].<ref>[http://qwiki.stanford.edu/index.php/Spin_Squeezed_State Database error – Qwiki] {{webarchive|url=https://web.archive.org/web/20120821011018/http://qwiki.stanford.edu/index.php/Spin_Squeezed_State |date=21 August 2012 }}</ref> Spin squeezed states are a class of [[squeezed coherent states]] satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled.<ref>{{cite journal | last1 = Kitagawa | first1 = Masahiro | last2 = Ueda | first2 = Masahito | year = 1993 | title = Squeezed Spin States | journal = Phys. Rev. A | volume = 47 | issue = 6| pages = 5138–5143 | doi=10.1103/physreva.47.5138| pmid = 9909547 |bibcode = 1993PhRvA..47.5138K }}</ref> Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<ref>{{cite journal | last1 = Wineland | first1 = D. J. | last2 = Bollinger | first2 = J. J. | last3 = Itano | first3 = W. M. | last4 = Moore | first4 = F. L. | last5 = Heinzen | first5 = D. J. | year = 1992| title = Spin squeezing and reduced quantum noise in spectroscopy | url = | journal = Phys. Rev. A | volume = 46| issue = 11| pages = R6797–R6800| doi = 10.1103/PhysRevA.46.R6797 | pmid = 9908086 |bibcode = 1992PhRvA..46.6797W }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<br />
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生物体(绿色硫细菌)已被研究作为介质,在非相互作用的光模式之间创造量子纠缠,表明光和细菌模式之间的高度纠缠,甚至在某种程度上纠缠在细菌内部。<br />
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For two [[boson]]ic modes, a [[NOON state]] is<br />
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: <math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the ''N'' photons are in one mode" and "the ''N'' photons are in the other mode".<br />
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Finally, there also exist [[twin Fock states]] for bosonic modes, which can be created by feeding a [[Fock state]] into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.71.1355|pmid = 10055519|title = Interferometric detection of optical phase shifts at the Heisenberg limit|journal = Physical Review Letters|volume = 71|issue = 9|pages = 1355–1358|year = 1993|last1 = Holland|first1 = M. J|last2 = Burnett|first2 = K|bibcode = 1993PhRvL..71.1355H}}</ref><br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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=== Methods of creating entanglement ===<br />
<br />
Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is [[spontaneous parametric down-conversion]] to generate a pair of photons entangled in polarisation.<ref name="horodecki2007">{{cite journal |author=Horodecki R, Horodecki P, Horodecki M, Horodecki K |title=Quantum entanglement |journal=Rev. Mod. Phys. |arxiv=quant-ph/0702225 |doi =10.1103/RevModPhys.81.865 |year=2009|pages=865–942 |bibcode=2009RvMP...81..865H |volume=81 |issue=2|last2=Horodecki |last3=Horodecki |last4=Horodecki |s2cid=59577352 }}</ref> Other methods include the use of a [[fiber coupler]] to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a [[quantum dot]],<ref>{{Cite journal|last=Akopian|first=N.|date=2006|title=Entangled Photon Pairs from Semiconductor Quantum Dots|journal=Phys. Rev. Lett.|volume=96|issue=2|pages=130501|arxiv=quant-ph/0509060|bibcode=2006PhRvL..96b0501D|doi=10.1103/PhysRevLett.96.020501|pmid=16486553|s2cid=22040546}}</ref> the use of the [[Hong–Ou–Mandel effect]], etc., In the earliest tests of Bell's theorem, the entangled particles were generated using [[atomic cascade]]s.<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of [[Quantum teleportation#Entanglement swapping|entanglement swapping]]. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<ref>Rosario Lo Franco and Giuseppe Compagno, "Indistinguishability of Elementary Systems as a Resource for Quantum Information Processing", Phys. Rev. Lett. 120, 240403, 14 June 2018.</ref><br />
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=== Testing a system for entanglement ===<br />
<br />
<br />
<br />
A density matrix ρ is called [[Separable state|separable]] if it can be written as a convex sum of product states, namely<br />
<br />
<br />
<br />
<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
<br />
<br />
<br />
with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
<br />
<br />
<br />
For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple [[Peres–Horodecki criterion]] provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes [[NP-hard]] when generalized.<ref name="NP-hard1">Gurvits, L., Classical deterministic complexity of Edmonds' problem and quantum entanglement, in Proceedings of the 35th ACM Symposium on Theory of Computing, ACM Press, New York, 2003.</ref><ref name="NP-hard2">Sevag Gharibian, Strong NP-Hardness of the [[Quantum Separability Problem]], [[Quantum Information]] and what's known as [[Quantum Computing]], Vol. 10, No. 3&4, pp. 343–360, 2010. {{arXiv|0810.4507}}.</ref> Other separability criteria include (but not limited to) the [[range criterion]], [[reduction criterion]], and those based on uncertainty relations.<ref>{{cite journal |last1=Hofmann |first1=Holger F. |last2=Takeuchi |first2=Shigeki |title=Violation of local uncertainty relations as a signature of entanglement |journal=Physical Review A |date=22 September 2003 |volume=68 |issue=3 |page=032103 |doi=10.1103/PhysRevA.68.032103|arxiv=quant-ph/0212090 |bibcode=2003PhRvA..68c2103H |s2cid=54893300 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |title=Characterizing Entanglement via Uncertainty Relations |journal=Physical Review Letters |date=18 March 2004 |volume=92 |issue=11 |page=117903 |doi=10.1103/PhysRevLett.92.117903|pmid=15089173 |arxiv=quant-ph/0306194 |bibcode=2004PhRvL..92k7903G |s2cid=5696147 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |last2=Lewenstein |first2=Maciej |title=Entropic uncertainty relations and entanglement |journal=Physical Review A |date=24 August 2004 |volume=70 |issue=2 |page=022316 |doi=10.1103/PhysRevA.70.022316|bibcode=2004PhRvA..70b2316G |arxiv=quant-ph/0403219 |s2cid=118952931 }}</ref><ref>{{cite journal |last1=Huang |first1=Yichen |title=Entanglement criteria via concave-function uncertainty relations |journal=Physical Review A |date=29 July 2010 |volume=82 |issue=1 |page=012335 |doi=10.1103/PhysRevA.82.012335|bibcode=2010PhRvA..82a2335H }}</ref> See Ref.<ref>{{cite journal|last1=Gühne|first1=Otfried|last2=Tóth|first2=Géza|title=Entanglement detection|journal=Physics Reports|volume=474|issue=1–6|pages=1–75|doi=10.1016/j.physrep.2009.02.004|arxiv = 0811.2803 |bibcode = 2009PhR...474....1G |year=2009|s2cid=119288569}}</ref> for a review of separability criteria in discrete variable systems.<br />
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<br />
<br />
A numerical approach to the problem is suggested by [[Jon Magne Leinaas]], [[Jan Myrheim]] and [[Eirik Ovrum]] in their paper "Geometrical aspects of entanglement".<ref name="geom approach">{{cite journal | last1 = Leinaas| first1 = Jon Magne| last2 = Myrheim| first2 = Jan| last3 = Ovrum| first3 = Eirik| year = 2006 | title = Geometrical aspects of entanglement | url = | journal = Physical Review A | volume = 74 | issue = | page = 012313 | doi = 10.1103/PhysRevA.74.012313| arxiv = quant-ph/0605079| s2cid = 119443360}}</ref> Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in [[Peres-Horodecki criterion]] testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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In continuous variable systems, the [[Peres-Horodecki criterion]] also applies. Specifically, Simon <ref>{{cite journal|last1=Simon|first1=R.|title=Peres-Horodecki Separability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2726–2729|doi=10.1103/PhysRevLett.84.2726|arxiv = quant-ph/9909044 |bibcode = 2000PhRvL..84.2726S|pmid=11017310|year=2000|s2cid=11664720}}</ref> formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref.<ref>{{cite journal|last1=Duan|first1=Lu-Ming|last2=Giedke|first2=G.|last3=Cirac|first3=J. I.|last4=Zoller|first4=P.|title=Inseparability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2722–2725|doi=10.1103/PhysRevLett.84.2722|pmid=11017309|arxiv = quant-ph/9908056 |bibcode = 2000PhRvL..84.2722D |year=2000|s2cid=9948874}}</ref> for a seemingly different but essentially equivalent approach). It was later found <ref>{{cite journal|last1=Werner|first1=R. F.|last2=Wolf|first2=M. M.|title=Bound Entangled Gaussian States|journal=Physical Review Letters|volume=86|issue=16|pages=3658–3661|doi=10.1103/PhysRevLett.86.3658|pmid=11328047|arxiv = quant-ph/0009118 |bibcode = 2001PhRvL..86.3658W |year=2001|s2cid=20897950}}</ref> that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators <ref>{{cite journal|last1=Shchukin|first1=E.|last2=Vogel|first2=W.|title=Inseparability Criteria for Continuous Bipartite Quantum States|journal=Physical Review Letters|volume=95|issue=23|pages=230502|doi=10.1103/PhysRevLett.95.230502|pmid=16384285|arxiv = quant-ph/0508132 |bibcode = 2005PhRvL..95w0502S |year=2005|s2cid=28595936}}</ref><ref>{{cite journal|last1=Hillery|first1=Mark|last2=Zubairy|first2=M.Suhail|title=Entanglement Conditions for Two-Mode States|journal=Physical Review Letters|volume=96|issue=5|doi=10.1103/PhysRevLett.96.050503|arxiv = quant-ph/0507168 |bibcode = 2006PhRvL..96e0503H|pmid=16486912|page=050503|year=2006|s2cid=43756465}}</ref> or by using entropic measures.<ref>{{cite journal|last1=Walborn|first1=S.|last2=Taketani|first2=B.|last3=Salles|first3=A.|last4=Toscano|first4=F.|last5=de Matos Filho|first5=R.|title=Entropic Entanglement Criteria for Continuous Variables|journal=Physical Review Letters|volume=103|issue=16|doi=10.1103/PhysRevLett.103.160505|arxiv = 0909.0147 |bibcode = 2009PhRvL.103p0505W|pmid=19905682|page=160505|year=2009|s2cid=10523704}}</ref><ref>{{cite journal |last1=Yichen Huang |title=Entanglement Detection: Complexity and Shannon Entropic Criteria |journal=IEEE Transactions on Information Theory |date=October 2013 |volume=59 |issue=10 |pages=6774–6778 |doi=10.1109/TIT.2013.2257936|s2cid=7149863 }}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite.<ref>http://physicsworld.com/cws/article/news/2016/aug/16/china-launches-world-s-first-quantum-science-satellite</ref> The $100m [[Quantum Experiments at Space Scale]] (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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In the June 16, 2017, issue of ''Science'', Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<ref>{{cite journal | doi = 10.1126/science.aan3211 | volume=356 | title=Satellite-based entanglement distribution over 1200 kilometers | year=2017 | journal=Science | pages=1140–1144 | last1 = Yin | first1 = Juan | last2 = Cao | first2 = Yuan | last3 = Li | first3 = Yu-Huai | last4 = Liao | first4 = Sheng-Kai | last5 = Zhang | first5 = Liang | last6 = Ren | first6 = Ji-Gang | last7 = Cai | first7 = Wen-Qi | last8 = Liu | first8 = Wei-Yue | last9 = Li | first9 = Bo | last10 = Dai | first10 = Hui | last11 = Li | first11 = Guang-Bing | last12 = Lu | first12 = Qi-Ming | last13 = Gong | first13 = Yun-Hong | last14 = Xu | first14 = Yu | last15 = Li | first15 = Shuang-Lin | last16 = Li | first16 = Feng-Zhi | last17 = Yin | first17 = Ya-Yun | last18 = Jiang | first18 = Zi-Qing | last19 = Li | first19 = Ming | last20 = Jia | first20 = Jian-Jun | last21 = Ren | first21 = Ge | last22 = He | first22 = Dong | last23 = Zhou | first23 = Yi-Lin | last24 = Zhang | first24 = Xiao-Xiang | last25 = Wang | first25 = Na | last26 = Chang | first26 = Xiang | last27 = Zhu | first27 = Zhen-Cai | last28 = Liu | first28 = Nai-Le | last29 = Chen | first29 = Yu-Ao | last30 = Lu | first30 = Chao-Yang | last31 = Shu | first31 = Rong | last32 = Peng | first32 = Cheng-Zhi | last33 = Wang | first33 = Jian-Yu | last34 = Pan | first34 = Jian-Wei | issue=6343 | pmid = 28619937| doi-access = free }}</ref><ref>{{cite web | url=http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance | title=China's quantum satellite achieves 'spooky action' at record distance| date=2017-06-14}}</ref><br />
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== Naturally entangled systems ==<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be [[Configuration interaction|calculated]] only by consideration of electron entanglement.<ref>Frank Jensen: ''Introduction to Computational Chemistry.'' Wiley, 2007, {{ISBN|978-0-470-01187-4}}.</ref><br />
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== Photosynthesis ==<br />
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It has been suggested that in the process of [[photosynthesis]], entanglement is involved in the transfer of energy between [[light-harvesting complex]]es and [[photosynthetic reaction center]]s where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using [[femtosecond spectroscopy]], the coherence of entanglement in the [[Fenna-Matthews-Olson complex]] was measured over hundreds of [[femtosecond]]s (a relatively long time in this regard) providing support to this theory.<ref>Berkeley Lab Press Release: ''[http://newscenter.lbl.gov/feature-stories/2010/05/10/untangling-quantum-entanglement/ Untangling the Quantum Entanglement Behind Photosynthesis: Berkeley scientists shine new light on green plant secrets.]''</ref><ref>Mohan Sarovar, Akihito Ishizaki, Graham R. Fleming, K. Birgitta Whaley: ''Quantum entanglement in photosynthetic light harvesting complexes.'' {{arxiv|0905.3787}}</ref><br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<ref>{{cite journal | author = R. Tempelaar | author2 = T. L. C. Jansen | author3 = J. Knoester | title = Vibrational Beatings Conceal Evidence of Electronic Coherence in the FMO Light-Harvesting Complex | journal = J. Phys. Chem. B | volume = 118 | issue = 45 | pages = 12865–12872 | date = 2014 | doi=10.1021/jp510074q| pmid = 25321492 }}</ref><ref>{{cite journal | author = N. Christenson | author2 = H. F. Kauffmann | author3 = T. Pullerits | author4 = T. Mancal | title = Origin of Long-Lived Coherences in Light-Harvesting Complexes| journal = J. Phys. Chem. B | volume = 116 | issue = 25 | pages = 7449–7454 | date = 2012 | doi = 10.1021/jp304649c | pmid = 22642682 | pmc = 3789255 | bibcode = 2012arXiv1201.6325C | arxiv = 1201.6325 }}</ref><ref>{{cite journal | author = A. Kolli | author2 = E. J. O’Reilly | author3= G. D. Scholes | author4= A. Olaya-Castro | title = The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae| journal = J. Chem. Phys. | volume = 137 | issue = 17 | pages = 174109 | date = 2012 | doi=10.1063/1.4764100| pmid = 23145719 | bibcode = 2012JChPh.137q4109K | arxiv = 1203.5056 | s2cid = 20156821 }}</ref><ref>{{cite journal | author = V. Butkus | author2 = D. Zigmantas | author3= L. Valkunas | author4= D. Abramavicius | title = Vibrational vs. electronic coherences in 2D spectrum of molecular systems| journal = Chem. Phys. Lett. | volume = 545 | issue = 30 | pages = 40–43 | date = 2012 | doi=10.1016/j.cplett.2012.07.014| arxiv = 1201.2753 | bibcode = 2012CPL...545...40B | s2cid = 96663719 }}</ref><ref>{{cite journal | author = V. Tiwari | author2 = W. K. Peters | author3= D. M. Jonas | title = Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework | journal = Proc. Natl. Acad. Sci. USA | volume = 110 | issue = 4 | pages = 1203–1208 | date = 2013 | doi=10.1073/pnas.1211157110| pmid = 23267114 | pmc = 3557059 }}</ref><ref>{{cite journal | author = E. Thyrhaug | author2 = K. Zidek | author3 = J. Dostal | author4 = D. Bina | author5 = D. Zigmantas | title = Exciton Structure and Energy Transfer in the Fenna−Matthews− Olson Complex| journal = J. Phys. Chem. Lett. | volume = 7 | issue = 9 | pages = 1653–1660 | date = 2016 | doi=10.1021/acs.jpclett.6b00534| pmid = 27082631 }}</ref><ref>{{cite journal | author = Y. Fujihashi | author2 = G. R. Fleming | author3= A. Ishizaki | title = Impact of environmentally induced fluctuations on quantum mechanically mixed electronic and vibrational pigment states in photosynthetic energy transfer and 2D electronic spectra| journal = J. Chem. Phys. | volume = 142 | issue = 21 | pages = 212403 | date = 2015 | doi=10.1063/1.4914302| pmid = 26049423 | arxiv = 1505.05281 | bibcode = 2015JChPh.142u2403F | s2cid = 1082742 }}</ref><br />
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== Entanglement of macroscopic objects ==<br />
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In 2020 researchers reported the quantum entanglement between the [[Vibrations of a circular membrane|motion of a millimetre-sized mechanical oscillator]] and a disparate distant [[Spin (physics)|spin]] system of a cloud of atoms.<ref>{{cite news |title=Quantum entanglement realized between distant large objects |url=https://phys.org/news/2020-09-quantum-entanglement-distant-large.html |accessdate=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Thomas |first1=Rodrigo A. |last2=Parniak |first2=Michał |last3=Østfeldt |first3=Christoffer |last4=Møller |first4=Christoffer B. |last5=Bærentsen |first5=Christian |last6=Tsaturyan |first6=Yeghishe |last7=Schliesser |first7=Albert |last8=Appel |first8=Jürgen |last9=Zeuthen |first9=Emil |last10=Polzik |first10=Eugene S. |title=Entanglement between distant macroscopic mechanical and spin systems |journal=Nature Physics |date=21 September 2020 |pages=1–6 |doi=10.1038/s41567-020-1031-5 |url=https://www.nature.com/articles/s41567-020-1031-5 |accessdate=9 October 2020 |language=en |issn=1745-2481}}</ref><br />
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=== Entanglement of elements of living systems ===<br />
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In October 2018, physicists reported producing quantum entanglement using [[living organism]]s, particularly between photosynthetic molecules within living [[bacteria]] and [[Photon|quantized light]].<ref name="JPC-20181010">{{cite journal |last1=Marletto |first1=C. |last2=Coles |first2=D.M. |last3=Farrow |first3=T. |last4=Vedral |first4=V. |title=Entanglement between living bacteria and quantized light witnessed by Rabi splitting |date=10 October 2018 |journal=Journal of Physics: Communications |volume=2 |pages=101001 |number=10 |doi=10.1088/2399-6528/aae224 |bibcode=2018JPhCo...2j1001M |arxiv=1702.08075 |s2cid=119236759 }} [[File:CC-BY icon.svg|50px]] Text and images are available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref><ref name="SA-20181029">{{cite web |last=O'Callaghan |first=Jonathan |title="Schrödinger's Bacterium" Could Be a Quantum Biology Milestone – A recent experiment may have placed living organisms in a state of quantum entanglement |url=https://www.scientificamerican.com/article/schroedingers-bacterium-could-be-a-quantum-biology-milestone/ |date=29 October 2018 |work=[[Scientific American]] |accessdate=29 October 2018 }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<ref>{{cite journal | last1 = Krisnanda | first1 = T. | last2 = Marletto | first2 = C. | last3 = Vedral | first3 = V. | last4 = Paternostro | first4 = M. | last5 = Paterek | first5 = T. | year = 2018 | title = Probing quantum features of photosynthetic organisms | url = https://www.nature.com/articles/s41534-018-0110-2 | journal = NPJ Quantum Information | volume = 4 | issue = | page = 60 | doi = 10.1038/s41534-018-0110-2 | doi-access = free }}</ref><br />
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== See also ==<br />
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{{Portal|Physics}}<br />
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{{cols|colwidth=21em}}<br />
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* [[Quantum gate#Controlled gates|CNOT gate]]<br />
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* [[Bound entanglement]]<br />
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* [[Concurrence (quantum computing)]]<br />
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* [[Einstein's thought experiments]]<br />
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* [[Entanglement distillation]]<br />
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* [[Entanglement witness]]<br />
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* [[Faster-than-light communication]]<br />
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* [[Ghirardi–Rimini–Weber theory]]<br />
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* [[Multipartite entanglement]]<br />
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* [[Normally distributed and uncorrelated does not imply independent]]<br />
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* [[Observer effect (physics)]]<br />
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* [[Quantum coherence]]<br />
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* [[Quantum discord]]<br />
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* [[Quantum phase transition]]<br />
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* [[Quantum computing]]<br />
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* [[Quantum network]]<br />
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Category:Quantum information science<br />
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类别: 量子信息科学<br />
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* [[Quantum pseudo-telepathy]]<br />
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Category:Quantum mechanics<br />
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类别: 量子力学<br />
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* [[Quantum teleportation]]<br />
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Category:Unsolved problems in physics<br />
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类别: 物理学中未解决的问题<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Quantum entanglement]]. Its edit history can be viewed at [[量子纠缠/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%87%8F%E5%AD%90%E7%BA%A0%E7%BC%A0&diff=21118量子纠缠2021-01-22T05:42:55Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Correlation between measurements of quantum subsystems, even when spatially separated}}<br />
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[[File:SPDC figure.png|right|thumb|275px|[[Spontaneous parametric down-conversion]] process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[[Spontaneous parametric down-conversion process can split photons into type II photon pairs with mutually perpendicular polarization.]]<br />
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[自发参量下转换过程可以将光子分裂成具有相互垂直极化的 II 型光子对。]<br />
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{{Quantum mechanics|fundamentals}}<br />
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'''Quantum entanglement''' is a physical phenomenon that occurs when a pair or group of [[particle]]s are generated, interact, or share spatial proximity in a way such that the [[quantum state]] of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the [[principle of locality|disparity between classical and quantum physics]]: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles are generated, interact, or share spatial proximity in a way such that the quantum state of each particle of the pair or group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics lacking in classical mechanics.<br />
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量子纠缠是一种物理现象,当一对或一组粒子产生、相互作用或共享空间邻近时,这对或一组粒子的量子态不能独立于其他粒子的状态来描述,包括粒子被很大距离分开时。量子纠缠的主题是经典物理学和量子物理学之间差距的核心: 纠缠是量子力学缺乏的经典力学的一个主要特征。<br />
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[[Measurement#Quantum mechanics|Measurements]] of [[physical properties]] such as [[position (vector)|position]], [[momentum]], [[spin (physics)|spin]], and [[polarization (waves)|polarization]] performed on entangled particles can, in some cases, be found to be perfectly [[correlated]]. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly [[paradox]]ical effects: any measurement of a property of a particle results in an irreversible [[wave function collapse]] of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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Measurements of physical properties such as position, momentum, spin, and polarization performed on entangled particles can, in some cases, be found to be perfectly correlated. For example, if a pair of entangled particles is generated such that their total spin is known to be zero, and one particle is found to have clockwise spin on a first axis, then the spin of the other particle, measured on the same axis, will be found to be counterclockwise. However, this behavior gives rise to seemingly paradoxical effects: any measurement of a property of a particle results in an irreversible wave function collapse of that particle and will change the original quantum state. In the case of entangled particles, such a measurement will affect the entangled system as a whole.<br />
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在某些情况下,对纠缠态粒子的物理性质如位置、动量、自旋和极化的测量可以被发现是完全相关的。例如,如果产生一对纠缠的粒子,它们的总自旋已知为零,并且其中一个粒子被发现在第一个轴上有顺时针的自旋,那么在同一个轴上测量的另一个粒子的自旋将被发现为逆时针方向。然而,这种行为产生了看似矛盾的效应: 任何对粒子性质的测量都会导致该粒子的不可逆波函数崩溃,并将改变原来的量子态。在纠缠粒子的情况下,这种测量会影响整个纠缠系统。<br />
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Such phenomena were the subject of a 1935 paper by [[Albert Einstein]], [[Boris Podolsky]], and [[Nathan Rosen]],<ref name="Einstein1935"><br />
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Such phenomena were the subject of a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen, and several papers by Erwin Schrödinger shortly thereafter, describing what came to be known as the EPR paradox. Einstein and others considered such behavior to be impossible, as it violated the local realism view of causality (Einstein referring to it as "spooky action at a distance") and argued that the accepted formulation of quantum mechanics must therefore be incomplete.<br />
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1935年,Albert Einstein,Boris Podolsky 和 Nathan Rosen 发表了一篇论文,此后不久,埃尔温·薛定谔也发表了几篇论文,描述了 EPR 悖论。爱因斯坦和其他人认为这种行为是不可能的,因为它违反了因果关系的局部实在论观点(爱因斯坦称之为“鬼魅般的超距作用”) ,并认为公认的量子力学公式因此是不完整的。<br />
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{{cite journal|author=Einstein A, Podolsky B, Rosen N|last2=Podolsky|last3=Rosen|year=1935|title=Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?|journal=Phys. Rev.|volume=47|issue=10|pages=777–780|bibcode=1935PhRv...47..777E|doi=10.1103/PhysRev.47.777|doi-access=free}}<br />
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</ref> and several papers by [[Erwin Schrödinger]] shortly thereafter,<ref name="Schrödinger1935"><br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<br />
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然而,后来,量子力学的违反直觉的预测被实验证实了。然而,所谓的“无漏洞”贝尔测试已经进行,在这个测试中,位置被分开,以光速进行通信所需的时间将会更长——在一个实验中,比测量间隔时间长10000倍。<br />
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According to some interpretations of quantum mechanics, the effect of one measurement occurs instantly. Other interpretations which don't recognize wavefunction collapse dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces correlation between the measurements and that the mutual information between the entangled particles can be exploited, but that any transmission of information at faster-than-light speeds is impossible.<br />
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根据一些量子力学诠释的研究,一次测量的效果会立即出现。其他不承认波函数塌缩的解释则质疑其中是否存在任何“效果”。然而,所有的解释都一致认为纠缠态产生了测量之间的相关性,纠缠态粒子之间的相互信息可以利用,但是任何信息的传输都不可能达到超光速。<br />
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Quantum entanglement has been demonstrated experimentally with photons, neutrinos, electrons, molecules as large as buckyballs, and even small diamonds. The utilization of entanglement in communication, computation and quantum radar is a very active area of research and development.<br />
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量子纠缠已经通过光子、中微子、电子、巴基球大小的分子甚至是小钻石的实验得到了证实。纠缠在通信、计算和量子雷达中的应用是一个非常活跃的研究领域。<br />
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Article headline regarding the [[Einstein–Podolsky–Rosen paradox (EPR paradox) paper, in the May 4, 1935 issue of The New York Times.]]<br />
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文章标题关于[爱因斯坦-波多尔斯基-罗森悖论(EPR paradox)论文,发表于1935年5月4日的《纽约时报》]<br />
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|doi=10.1017/S0305004100013554<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.<br />
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1935年,Albert Einstein 在与 Boris Podolsky 和 Nathan Rosen 的联合论文中首次讨论了量子力学关于强相关系统的违反直觉的预测。<br />
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|bibcode = 1935PCPS...31..555S }}</ref><ref name="Schrödinger1936"><br />
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{{cite journal |author=Schrödinger E<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated: Einstein later famously derided entanglement as "spukhafte Fernwirkung" or "spooky action at a distance."<br />
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此后不久,薛定谔发表了一篇影响深远的论文,定义并讨论了“纠缠”的概念在论文中,他承认了这个概念的重要性,并指出: 爱因斯坦后来著名地嘲笑纠缠为“ spukhafte Fernwirkung”或“幽灵般的超距作用”<br />
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|title=Probability relations between separated systems<br />
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|journal=Mathematical Proceedings of the Cambridge Philosophical Society<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously Bohm's interpretation of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when John Stewart Bell proved that one of their key assumptions, the principle of locality, as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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这篇 EPR 论文在物理学家中引起了极大的兴趣,激发了许多关于量子力学基础的讨论(也许最著名的是 Bohm 对量子力学的解释) ,但是其他发表的工作相对较少。尽管如此,EPR 论证中的弱点直到1964年才被发现,当时约翰·斯图尔特·贝尔证明了他们的一个关键假设---- 应用于 EPR 所希望的那种隐变量解释的定域性原理,在数学上与量子理论的预测不一致。<br />
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Specifically, Bell demonstrated an upper limit, seen in Bell's inequality, regarding the strength of correlations that can be produced in any theory obeying local realism, and showed that quantum theory predicts violations of this limit for certain entangled systems. His inequality is experimentally testable, and there have been numerous relevant experiments, starting with the pioneering work of Stuart Freedman and John Clauser in 1972 and Alain Aspect's experiments in 1982. An early experimental breakthrough was due to Carl Kocher, Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles. Alain Aspect notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / superdeterminism loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<br />
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具体来说,贝尔证明了一个上限,可以在贝尔不等式中看到,关于在任何服从局部实在论的理论中都可以产生的相关性的强度,并且显示了量子理论预测了某些纠缠系统违反这个上限。他的不等式在实验上是可以检验的,并且已经有了大量的相关实验,从1972年斯图尔特 · 弗里德曼和约翰 · 克劳泽的开创性工作和1982年阿兰 · 阿斯派克特的实验开始。一个早期的实验突破是由于 Carl Kocher 的仪器,Kocher 的仪器配备了更好的偏振器,被 Freedman 和 Clauser 使用,他们可以证实余弦平方相关性,并用它来证明对一组固定角度的 Bell 不等式的违反。阿兰 · 阿斯派克特指出,“设置独立性漏洞”——他称之为“牵强附会” ,然而,一个“不可忽视”的“残余漏洞”——尚未被关闭,自由意志/超决定论是不可忽视的; 他说,“没有任何实验,尽管理想,可以说是完全没有漏洞的。”<br />
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|pages=446–452<br />
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A minority opinion holds that although quantum mechanics is correct, there is no superluminal instantaneous action-at-a-distance between entangled particles once the particles are separated.<br />
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少数人认为,尽管量子力学是正确的,但是一旦粒子分离,纠缠的粒子之间并不存在超光速瞬时作用。<br />
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|doi=10.1017/S0305004100019137<br />
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|bibcode = 1936PCPS...32..446S }}<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of quantum key distribution protocols, most famously BB84 by Charles H. Bennett and Gilles Brassard and E91 by Artur Ekert. Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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贝尔的工作提高了利用这些超强相关性作为沟通资源的可能性。它导致了1984年量子密钥分配协议的发现,其中最著名的是由 Charles h. Bennett 和 Gilles Brassard 提出的 BB84,以及由 Artur Ekert 提出的 E91。虽然 BB84不使用纠缠,但是 Ekert 的协议使用违反 Bell 不等式作为安全性的证据。<br />
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</ref> describing what came to be known as the [[EPR paradox]]. Einstein and others considered such behavior to be impossible, as it violated the [[local realism]] view of causality (Einstein referring to it as "spooky [[action at a distance]]")<ref>Physicist John Bell depicts the Einstein camp in this debate in his article entitled "Bertlmann's socks and the nature of reality", p. 143 of ''Speakable and unspeakable in quantum mechanics'': "For EPR that would be an unthinkable 'spooky action at a distance'. To avoid such action at a distance they have to attribute, to the space-time regions in question, real properties in advance of observation, correlated properties, which predetermine the outcomes of these particular observations. Since these real properties, fixed in advance of observation, are not contained in quantum formalism, that formalism for EPR is incomplete. It may be correct, as far as it goes, but the usual quantum formalism cannot be the whole story." And again on p. 144 Bell says: "Einstein had no difficulty accepting that affairs in different places could be correlated. What he could not accept was that an intervention at one place could influence, immediately, affairs at the other." Downloaded 5 July 2011 from {{cite book |year=1987 |accessdate=2014-06-14 |title=Speakable and Unspeakable in Quantum Mechanics |first=J. S. |last=Bell |publisher=[[CERN]] |isbn=0521334950 |url=http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |url-status=dead |archiveurl=https://web.archive.org/web/20150412044550/http://philosophyfaculty.ucsd.edu/faculty/wuthrich/GSSPP09/Files/BellJohnS1981Speakable_BertlmannsSocks.pdf |archivedate=12 April 2015 |df=dmy-all }}</ref> and argued that the accepted formulation of [[quantum mechanics]] must therefore be incomplete.<br />
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Later, however, the counterintuitive predictions of quantum mechanics were verified experimentally<ref name=":0" /><ref name=":1" /><ref name=":2" /> in tests in which polarization or spin of entangled particles were measured at separate locations, statistically violating [[Bell's inequality]]. In earlier tests, it couldn't be absolutely ruled out that the test result at one point could have been [[Loopholes in Bell test experiments|subtly transmitted]] to the remote point, affecting the outcome at the second location.<ref name=":2">Francis, Matthew.<br />
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[https://arstechnica.com/science/2012/10/quantum-entanglement-shows-that-reality-cant-be-local/ Quantum entanglement shows that reality can't be local], ''Ars Technica'', 30 October 2012</ref> However, so-called "loophole-free" Bell tests have been performed in which the locations were separated such that communications at the speed of light would have taken longer--in one case 10,000 times longer—than the interval between the measurements.<ref name=":1">{{cite journal|last1=Matson|first1=John|title=Quantum teleportation achieved over record distances|journal=Nature News|date=13 August 2012|doi=10.1038/nature.2012.11163|s2cid=124852641}}</ref><ref name=":0">{{cite journal<br />
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| title =Bounding the speed of 'spooky action at a distance<br />
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An entangled system is defined to be one whose quantum state cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or superposition, of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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量子纠缠系统的定义是: 量子态不能被分解为其局部成分的状态的产物; 也就是说,它们不是单个的粒子,而是一个不可分割的整体。在纠缠中,一个成分不能不考虑其他成分而被完全描述。复合系统的状态总是可以表示为局部组分状态的产物的和或叠加; 如果这个和必然有多个项,则它是纠缠的。<br />
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| journal =Physical Review Letters |volume=110 | issue =26 |page=260407<br />
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| year =2013<br />
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Quantum systems can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on methods. Entanglement is broken when the entangled particles decohere through interaction with the environment; for example, when a measurement is made.<br />
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量子系统可以通过各种类型的相互作用而纠缠在一起。关于一些可以用于实验目的的纠缠方法,请参阅下面的方法一节。当纠缠的粒子通过与环境的相互作用退相干时,纠缠就被打破了; 例如,当进行测量时。<br />
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As an example of entanglement: a subatomic particle decays into an entangled pair of other particles. The decay events obey the various conservation laws, and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a spin-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be spin up on some axis, the other, when measured on the same axis, is always found to be spin down. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the singlet state.)<br />
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作为纠缠的一个例子: 一个次原子粒子衰变成一对纠缠的其他粒子。衰变事件遵循不同的守恒定律,因此,一个子粒子的测量结果必须与另一个子粒子的测量结果高度相关(因此总动量、角动量、能量等在此过程前后大致相同)。例如,一个自旋为零的粒子可以衰变成一对自旋为1的粒子。由于衰变前后的总自旋必须为零(角动量守恒定律) ,每当第一个粒子在某一轴上被测量为自旋向上时,另一个粒子在同一轴上被测量时,总是被发现自旋向下。(这就是所谓的自旋反关联情况,如果测量每个自旋的先验概率是相等的,那么这对自旋就处于单线态。)<br />
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| doi = 10.1103/PhysRevLett.110.260407<br />
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| pmid =23848853 | last1 =Yin | first1 =Juan | last2 =Cao | first2 =Yuan | last3 =Yong | first3 =Hai-Lin | last4 =Ren | first4 =Ji-Gang | last5 =Liang | first5 =Hao | last6 =Liao | first6 =Sheng-Kai | last7 =Zhou | first7 =Fei | last8 =Liu | first8 =Chang | last9 =Wu | first9 =Yu-Ping | last10 =Pan | first10 =Ge-Sheng | last11 =Li | first11 =Li | last12 =Liu | first12 =Nai-Le | last13 =Zhang | first13 =Qiang | last14 =Peng | first14 =Cheng-Zhi | last15 =Pan | first15 =Jian-Wei | s2cid =119293698 }}</ref><br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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如果将这两种粒子分开,可以更好地观察到纠缠的特性。让我们把其中一个放在华盛顿的白宫,另一个放在白金汉宫。现在,如果我们测量其中一个粒子的特性(比如自旋) ,得到一个结果,然后用同样的标准(沿着同样的轴自旋)测量另一个粒子,我们发现第二个粒子的测量结果将匹配(在补充意义上)第一个粒子的测量结果,因为它们的值将相反。<br />
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According to ''some'' [[interpretations of quantum mechanics]], the effect of one measurement occurs instantly. Other interpretations which don't recognize [[wavefunction collapse]] dispute that there is any "effect" at all. However, all interpretations agree that entanglement produces ''[[correlation]]'' between the measurements and that the [[mutual information]] between the entangled particles can be exploited, but that any ''transmission'' of information at faster-than-light speeds is impossible.<ref>[[Roger Penrose]], ''The Road to Reality: A Complete Guide to the Laws of the Universe'', London, 2004, p. 603.</ref><ref name="Griffiths2004">{{citation | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |isbn= 978-0-13-111892-8}}</ref><br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a hidden variable theory (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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上述结果可能会也可能不会让人感到惊讶。一个经典的系统将显示相同的属性,并且一个隐变量理论系统(见下文)当然会被要求这样做,基于古典的和类似的角动量守恒定律量子力学系统。不同之处在于,一个经典系统对所有的可观测量一直都有确定的值,而量子系统则没有。在下面将要讨论的某种意义上,这里所考虑的量子系统似乎获得了一个概率分布,用于在测量第一个粒子时,测量沿着其他粒子的任何轴线的自旋。这个概率分布粒子通常不同于没有第一个粒子测量的情况。在空间分离的纠缠粒子的情况下,这当然可能被认为是令人惊讶的。<br />
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Quantum entanglement has been demonstrated experimentally with [[photon]]s,<ref name="Kocher1">{{cite journal | doi = 10.1103/PhysRevLett.18.575 | volume=18 | issue=15 | title=Polarization Correlation of Photons Emitted in an Atomic Cascade | journal=Physical Review Letters | pages=575–577 | last1 = Kocher | first1 = CA | last2 = Commins | first2 = ED | year=1967| url=http://www.escholarship.org/uc/item/1kb7660q | bibcode=1967PhRvL..18..575K }}</ref><ref name="Kocherphd">Carl A. Kocher, Ph.D. Thesis (University of California at Berkeley, 1967). ''[https://escholarship.org/uc/item/1kb7660q Polarization Correlation of Photons Emitted in an Atomic Cascade]''</ref> [[neutrino]]s,<ref>J. A. Formaggio, D. I. Kaiser, M. M. Murskyj, and T. E. Weiss (2016), "[https://journals.aps.org/prl/accepted/6f072Y00C3318d41f5739ec7f83a9acf1ad67b002 Violation of the Leggett-Garg inequality in neutrino oscillations]". ''Phys. Rev. Lett.'' Accepted 23 June 2016.</ref> [[electron]]s,<ref name="NTR-20151021">{{cite journal |author=Hensen, B. |title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres |date=21 October 2015 |journal=[[Nature (journal)|Nature]] |doi=10.1038/nature15759 |display-authors=etal |volume=526 |issue=7575 |pages=682–686|bibcode = 2015Natur.526..682H |pmid=26503041|arxiv=1508.05949 |hdl=2117/79298 |s2cid=205246446 }} See also [http://www.nature.com/articles/nature15759.epdf?referrer_access_token=1QB20mTNTZW60nEXil0D79RgN0jAjWel9jnR3ZoTv0Pfu6MWINxm4Io03p2jIRZ8qX_3I3N0Kr-AlItuikCZOJrG8QbdRRghlecFwmixlbQpWuw1dtaib4Le5DQOG3u_aXHU85x1JEhOcQTa1sHi0yvW23bblxmEQZAmHL4G0gIVusG_6JWorroY5BprgbTl4FiaE8WltEgMoUMZfZBkEfbMcFDp5iR112TFx_x3ZRj88Wa23E2moEvTfKjtlued0&tracking_referrer=www.nytimes.com free online access version].</ref><ref name="NYT-20151021">{{cite news |last=Markoff |first=Jack |title=Sorry, Einstein. Quantum Study Suggests 'Spooky Action' Is Real. |url=https://www.nytimes.com/2015/10/22/science/quantum-theory-experiment-said-to-prove-spooky-interactions.html |date=21 October 2015 |work=The New York Times |accessdate=21 October 2015 }}</ref> [[molecule]]s as large as [[buckyball]]s,<ref>{{cite journal | doi = 10.1038/44348 | title = Wave–particle duality of C<sub>60</sub> molecules | date= 14 October 1999 | volume=401 | issue = 6754 | journal=Nature | pages=680–682 | pmid=18494170|bibcode = 1999Natur.401..680A | last1 = Arndt | first1 = M | last2 = Nairz | first2 = O | last3 = Vos-Andreae | first3 = J | last4 = Keller | first4 = C | last5 = van der Zouw | first5 = G | last6 = Zeilinger | first6 = A| s2cid = 4424892 }} {{subscription}}</ref><ref>[[Olaf Nairz]], [[Markus Arndt]], and [[Anton Zeilinger]], "Quantum interference experiments with large molecules", American Journal of Physics, 71 (April 2003) 319–325.</ref> and even small diamonds.<ref>{{cite journal |journal=Science |date=2 December 2011 |volume=334 |issue=6060 |pages=1253–1256 |doi=10.1126/science.1211914 |pmid=22144620 |url=http://www.sciencemag.org/content/334/6060/1253.full |title=Entangling macroscopic diamonds at room temperature |lay-url=https://www.newscientist.com/article/dn21235-entangled-diamonds-blur-quantumclassical-divide.html|bibcode = 2011Sci...334.1253L |last1=Lee |first1=K. C. |last2=Sprague |first2=M. R. |last3=Sussman |first3=B. J. |last4=Nunn |first4=J. |last5=Langford |first5=N. K. |last6=Jin |first6=X.- M. |last7=Champion |first7=T. |last8=Michelberger |first8=P. |last9=Reim |first9=K. F. |last10=England |first10=D. |last11=Jaksch |first11=D. |last12=Walmsley |first12=I. A. |s2cid=206536690 }}</ref><ref>[http://www.sciencemag.org/content/334/6060/1253/suppl/DC1 sciencemag.org], supplementary materials</ref> The utilization of entanglement in [[quantum communication|communication]], [[quantum computing|computation]] and [[quantum radar]] is a very active area of research and development.<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<br />
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矛盾的是,对任何一个粒子的测量显然会破坏整个纠缠系统的状态,而且是在测量结果的任何信息可以传递给另一个粒子之前(假设信息不能比光传播得更快) ,从而确保对纠缠对的另一部分的测量结果是“适当的”。在哥本哈根诠释中,对其中一个粒子进行自旋测量的结果是一个崩塌状态,在这个状态中,每个粒子沿测量轴都有一个确定的自旋(上或下)。结果是随机的,每种可能性的概率都是50% 。然而,如果两个自旋都沿着同一个轴测量,就会发现它们是反相关的。这意味着对一个粒子进行测量的随机结果似乎已经传递给了另一个粒子,因此当它也被测量时,它可以做出“正确的选择”。<br />
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== History ==<br />
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[[File:NYT May 4, 1935.jpg|right|thumb| 250px|Article headline regarding the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox) paper, in the May 4, 1935 issue of ''[[The New York Times]]''.]]<br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, hence, any causal effect connecting the events would have to travel faster than light. According to the principles of special relativity, it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events and there are inertial frames in which is first and others in which is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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可以选择测量的距离和时间,使两个测量之间的间隔类似于空间,因此,任何连接事件的因果效应都必须比光传播得更快。根据狭义相对论原理,任何信息都不可能在两个这样的测量事件之间传递。甚至不可能说哪个测量结果是最先出现的。对于两个类空分离的事件,存在惯性系,其中一个是第一个,其他的是第一个。因此,两个测量值之间的相关性不能解释为一个测量值决定另一个测量值: 不同的观察者会对因果的作用有不同的看法。<br />
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The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by [[Albert Einstein]] in 1935, in a joint paper with [[Boris Podolsky]] and [[Nathan Rosen]].<ref name="Einstein1935"/><br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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(事实上,即使没有纠缠也会出现类似的悖论: 单个粒子的位置分布在空间上,两个相距很远的探测器试图在两个不同的地方探测粒子,必须同时达到适当的相关性,以便它们不能同时探测粒子。)<br />
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In this study, the three formulated the [[Einstein–Podolsky–Rosen paradox]] (EPR paradox), a [[thought experiment]] that attempted to show that [[quantum mechanics|quantum mechanical theory]] was [[Incompleteness of quantum physics|incomplete]]. They wrote: "We are thus forced to conclude that the quantum-mechanical description of physical reality given by wave functions is not complete."<ref name="Einstein1935"/><br />
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However, the three scientists did not coin the word ''entanglement'', nor did they generalize the special properties of the state they considered. Following the EPR paper, [[Erwin Schrödinger]] wrote a letter to Einstein in [[German language|German]] in which he used the word ''Verschränkung'' (translated by himself as ''entanglement'') "to describe the correlations between two particles that interact and then separate, as in the EPR experiment."<ref name=MK>Kumar, M., ''Quantum'', Icon Books, 2009, p. 313.</ref><br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables". The state of the particles being measured contains some hidden variables, whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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这一悖论的一个可能的解决办法是假定量子理论是不完整的,测量结果取决于预先确定的“隐变量”。被测粒子的状态包含一些隐藏的变量,它们的值有效地决定了,从分离的那一刻起,自旋测量的结果将会是什么。这意味着每个粒子都携带着所需的所有信息,在测量时不需要从一个粒子传递到另一个粒子。爱因斯坦和其他人(见上一节)最初认为这是唯一的出路的悖论,和公认的量子力学描述(随机测量结果)必须是不完整的。<br />
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Schrödinger shortly thereafter published a seminal paper defining and discussing the notion of "entanglement." In the paper, he recognized the importance of the concept, and stated:<ref name="Schrödinger1935"/> "I would not call [entanglement] ''one'' but rather ''the'' characteristic trait of [[quantum mechanics]], the one that enforces its entire departure from [[Classical mechanics|classical]] lines of thought."<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the local realist or hidden variables view were correct, the results would always satisfy Bell's inequality. A number of experiments have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists. When measurements of the entangled particles are made in moving relativistic reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<br />
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然而,当考虑沿不同轴线的纠缠粒子的自旋时,局部隐变量理论就失败了。如果在大量的纠缠粒子对上进行了大量的这样的测量,那么从统计学上来说,如果局域实在论或隐变量观点是正确的,那么结果总是满足 Bell 不等式。许多实验表明,贝尔不等式在实践中并不能得到满足。然而,在2015年之前,所有这些都存在漏洞问题,这被物理学界认为是最重要的。当在移动的相对论参照系中测量纠缠粒子时,每个测量(在其自身的相对论时间框架内)先于另一个进行,测量结果仍然是相关的。<br />
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Like Einstein, Schrödinger was dissatisfied with the concept of entanglement, because it seemed to violate the speed limit on the transmission of information implicit in the [[theory of relativity]].<ref>Alisa Bokulich, Gregg Jaeger, ''Philosophy of Quantum Information and Entanglement'', Cambridge University Press, 2010, xv.</ref> Einstein later famously derided entanglement as "''spukhafte Fernwirkung''"<ref name="spukhafte">Letter from Einstein to Max Born, 3 March 1947; ''The Born-Einstein Letters; Correspondence between Albert Einstein and Max and Hedwig Born from 1916 to 1955'', Walker, New York, 1971. (cited in {{citation | title = Quantum Entanglement and Communication Complexity (1998) | journal = SIAM J. Comput. | volume = 30 | issue = 6 | citeseerx = 10.1.1.20.8324 | author = M. P. Hobson |pages=1829–1841 | display-authors = etal | year = 1998 }})</ref> or "spooky [[Action at a distance (physics)|action at a distance]]."<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are incompatible in the sense that these measurements' maximum simultaneous precision is constrained by the uncertainty principle. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations, and thus entanglement is a fundamentally non-classical phenomenon.<br />
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沿不同轴线测量自旋的基本问题是,这些测量不可能同时具有确定的值——它们是不相容的,因为这些测量的最大同时精度受到不确定性原理的限制。这与经典物理学中的发现相反,在经典物理学中,任何数量的性质都可以以任意精度同时测量。从数学上证明了相容测量不能显示违反贝尔不等式的关联,因此纠缠是一个基本的非经典现象。<br />
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The EPR paper generated significant interest among physicists, which inspired much discussion about the foundations of quantum mechanics (perhaps most famously [[De Broglie–Bohm theory|Bohm's interpretation]] of quantum mechanics), but produced relatively little other published work. Despite the interest, the weak point in EPR's argument was not discovered until 1964, when [[John Stewart Bell]] proved that one of their key assumptions, the [[principle of locality]], as applied to the kind of hidden variables interpretation hoped for by EPR, was mathematically inconsistent with the predictions of quantum theory.<br />
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Entanglement is required to preserve the Uncertainty principle, as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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纠缠是保持不确定性原理所必需的,如 EPR 悖论所示。例如,假设一个高能光子衰变成一个电子/正电子对,然后测量电子的位置和正电子的动量。如果我们在物理描述中不允许纠缠,那么每个粒子的位置和动量仍然可以通过参考动量守恒来推导,这违反了测不准原理。或者,如果我们要求不确定性原理保持真实,而仍然不允许在物理描述对的纠缠,不确定性原理将允许违反动量守恒定律,因为在位置和动量上强相关性是不可能的(也就是说,人们不能有效地推断电子的位置和动量,因为它们不能与正电子的位置和动量高度相关)。--><br />
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Specifically, Bell demonstrated an upper limit, seen in [[Bell's inequality]], regarding the strength of correlations that can be produced in any theory obeying [[local realism]], and showed that quantum theory predicts violations of this limit for certain entangled systems.<ref>{{cite journal |author = J. S. Bell |title = On the Einstein-Poldolsky-Rosen paradox |journal = Physics Physique Физика |volume = 1 |issue = 3 |pages = 195–200 |year = 1964|doi = 10.1103/PhysicsPhysiqueFizika.1.195 |doi-access = free }}</ref> His inequality is experimentally testable, and there have been numerous [[Bell test experiments|relevant experiments]], starting with the pioneering work of [[Stuart Freedman]] and [[John Clauser]] in 1972<ref name="Clauser">{{cite journal|doi=10.1103/PhysRevLett.28.938|last1=Freedman|first1=Stuart J.|last2=Clauser|first2=John F.|title=Experimental Test of Local Hidden-Variable Theories|journal=Physical Review Letters |volume=28 |issue=14 |pages=938–941|year=1972 |bibcode=1972PhRvL..28..938F|url=https://escholarship.org/uc/item/2f18n5nk}}</ref> and [[Alain Aspect]]'s experiments in 1982.<ref>{{cite journal |author1=A. Aspect |author2=P. Grangier |author3=G. Roger |name-list-style=amp |title = Experimental Realization of Einstein-Podolsky-Rosen-Bohm Gedankenexperiment: A New Violation of Bell's Inequalities |journal = Physical Review Letters |volume = 49 |issue = 2 |pages = 91–94 |year = 1982 |doi = 10.1103/PhysRevLett.49.91 |bibcode=1982PhRvL..49...91A|doi-access = free }}</ref> An early experimental breakthrough was due to Carl Kocher,<ref name="Kocher1"/><ref name="Kocherphd"/> who already in 1967 presented an apparatus in which two photons successively emitted from a calcium atom were shown to be entangled – the first case of entangled visible light. The two photons passed diametrically positioned parallel polarizers with higher probability than classically predicted but with correlations in quantitative agreement with quantum mechanical calculations. He also showed that the correlation varied only upon (as cosine square of) the angle between the polarizer settings<ref name="Kocherphd"/> and decreased exponentially with time lag between emitted photons.<ref name="Kocher2">{{cite journal | doi = 10.1016/0003-4916(71)90159-X | volume=65 | issue=1 | title=Time correlations in the detection of successively emitted photons | journal=Annals of Physics | pages=1–18 | last1 = Kocher | first1 = CA | year=1971| bibcode=1971AnPhy..65....1K }}</ref> Kocher’s apparatus, equipped with better polarizers, was used by Freedman and Clauser who could confirm the cosine square dependence and use it to demonstrate a violation of Bell’s inequality for a set of fixed angles.<ref name="Clauser"/> All these experiments have shown agreement with quantum mechanics rather than the principle of local realism.<br />
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For decades, each had left open at least one [[Loopholes in Bell test experiments|loophole]] by which it was possible to question the validity of the results. However, in 2015 an experiment was performed that simultaneously closed both the detection and locality loopholes, and was heralded as "loophole-free"; this experiment ruled out a large class of local realism theories with certainty.<ref name="hanson">{{cite journal|last1=Hanson|first1=Ronald|title=Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres|journal=Nature|volume=526|issue=7575|pages=682–686|doi=10.1038/nature15759|arxiv=1508.05949|bibcode = 2015Natur.526..682H|pmid=26503041|year=2015|s2cid=205246446}}</ref> [[Alain Aspect]] notes that the "setting-independence loophole" – which he refers to as "far-fetched", yet, a "residual loophole" that "cannot be ignored" – has yet to be closed, and the free-will / ''[[superdeterminism]]'' loophole is unclosable; saying "no experiment, as ideal as it is, can be said to be totally loophole-free."<ref>{{Cite journal | title=Viewpoint: Closing the Door on Einstein and Bohr's Quantum Debate| journal=Physics| volume=8| date=2015-12-16| last1=Aspect| first1=Alain| page=123| doi=10.1103/physics.8.123| doi-access=free| bibcode=2015PhyOJ...8..123A}}</ref><br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time. The authors claimed that this result was achieved by entanglement swapping between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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在2012年和2013年的实验中,光子之间产生了偏振相关性,这种相关性从未在时间上共存过。作者认为,这一结果是通过测量早期纠缠光子对中一个光子的偏振态后,两对纠缠光子之间的纠缠交换实现的,并且证明了量子非局域性不仅适用于空间,也适用于时间。<br />
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A minority opinion holds that although quantum mechanics is correct, there is no [[faster-than-light|superluminal]] instantaneous action-at-a-distance between entangled particles once the particles are separated.<ref>{{Cite journal |doi = 10.1142/S0217979206034078|title = Correlations in Entangled States|journal = International Journal of Modern Physics B|volume = 20|issue = 11n13|pages = 1496–1503|year = 2006|last1 = Sanctuary|first1 = B. C|arxiv = quant-ph/0508238|bibcode = 2006IJMPB..20.1496S|s2cid = 119403050}}</ref><ref>{{Cite arxiv |eprint = quant-ph/0404011 |last1 = Yin |first1 = Juan |title = The Statistical Interpretation of Entangled States |last2 = Cao |first2 = Yuan |last3 = Yong |first3 = Hai-Lin |last4 = Ren |first4 = Ji-Gang |last5 = Liang |first5 = Hao |last6 = Liao |first6 = Sheng-Kai |last7 = Zhou |first7 = Fei |last8 = Liu |first8 = Chang |last9 = Wu |first9 = Yu-Ping |last10 = Pan |first10 = Ge-Sheng |last11 = Zhang |first11 = Qiang |last12 = Peng |first12 = Cheng-Zhi |last13 = Pan |first13 = Jian-Wei |year = 2004 }}</ref><ref>{{cite journal|doi=10.1002/prop.201600044 | volume=65 | issue=6–8 | title=After Bell | year=2016 | journal=Fortschritte der Physik | page=1600044 | last1 = Khrennikov | first1 = Andrei}}</ref><ref>{{Cite journal |arxiv = 1603.08674|last1 = Yin|first1 = Juan|title = After Bell|journal = Fortschritte der Physik (Progress in Physics)|date=2017|volume = 65|issue = 1600014|pages = 6–8|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|bibcode = 2016arXiv160308674K}}</ref><ref>{{Cite journal |arxiv = quant-ph/0703251|last1 = Yin|first1 = Juan|title = Classical statistical distributions can violate Bell-type inequalities|journal = Journal of Physics A: Mathematical and Theoretical|volume = 41|issue = 8|pages = 085303|last2 = Cao|first2 = Yuan|last3 = Yong|first3 = Hai-Lin|last4 = Ren|first4 = Ji-Gang|last5 = Liang|first5 = Hao|last6 = Liao|first6 = Sheng-Kai|last7 = Zhou|first7 = Fei|last8 = Liu|first8 = Chang|last9 = Wu|first9 = Yu-Ping|last10 = Pan|first10 = Ge-Sheng|last11 = Zhang|first11 = Qiang|last12 = Peng|first12 = Cheng-Zhi|last13 = Pan|first13 = Jian-Wei|year = 2007|doi = 10.1088/1751-8113/41/8/085303|s2cid = 46193162}}</ref><br />
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In three independent experiments in 2013 it was shown that classically communicated separable quantum states can be used to carry entangled states. The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<br />
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在2013年的三个独立实验中,我们发现经典通信的可分离量子态可以用来携带纠缠态。2015年,TU Delft 进行了第一次没有漏洞的贝尔测试,证实了贝尔不平等的违规性。<br />
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Bell's work raised the possibility of using these super-strong correlations as a resource for communication. It led to the 1984 discovery of [[quantum key distribution]] protocols, most famously [[BB84]] by [[Charles H. Bennett (computer scientist)|Charles H. Bennett]] and [[Gilles Brassard]]<ref>C. H. Bennett and G. Brassard. "Quantum cryptography: Public key distribution and coin tossing". In ''Proceedings of IEEE International Conference on Computers, Systems and Signal Processing'', volume 175, p. 8. New York, 1984. http://researcher.watson.ibm.com/researcher/files/us-bennetc/BB84highest.pdf</ref> and [[E91 protocol|E91]] by [[Artur Ekert]].<ref>{{cite journal|last=Ekert|first=A.K.|authorlink=Artur Ekert|title=Quantum cryptography based on Bell's theorem|journal=Phys. Rev. Lett.|volume=67|issue=6|year=1991|doi=10.1103/PhysRevLett.67.661|issn=0031-9007|bibcode = 1991PhRvL..67..661E|pmid=10044956|pages=661–663}}</ref> Although BB84 does not use entanglement, Ekert's protocol uses the violation of a Bell's inequality as a proof of security.<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<br />
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2014年8月,巴西研究人员加布里埃拉 · 巴雷托 · 莱莫斯和他的团队能够使用光子“拍摄”物体,这些光子并没有与实验对象发生相互作用,而是与这些物体发生了纠缠。来自维也纳大学的勒莫斯相信,这种新的量子成像技术可以在微光成像势在必行的领域找到应用,比如生物或医学成像。<br />
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== Concept ==<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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2015年,哈佛大学的 Markus Greiner 团队直接测量了超冷玻色子原子系统中的 Renyi 纠缠。<br />
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=== Meaning of entanglement ===<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<br />
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从2016年开始,各种各样的公司,如 IBM,微软等。已经成功地创造了量子计算机,并且允许开发者和技术爱好者公开地实验量子力学的概念,包括量子纠缠。<br />
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An entangled system is defined to be one whose [[quantum state]] cannot be factored as a product of states of its local constituents; that is to say, they are not individual particles but are an inseparable whole. In entanglement, one constituent cannot be fully described without considering the other(s). The state of a composite system is always expressible as a sum, or [[quantum superposition|superposition]], of products of states of local constituents; it is entangled if this sum necessarily has more than one term.<br />
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Quantum [[physical system|systems]] can become entangled through various types of interactions. For some ways in which entanglement may be achieved for experimental purposes, see the section below on [[#Methods of creating entanglement|methods]]. Entanglement is broken when the entangled particles [[quantum decoherence|decohere]] through interaction with the environment; for example, when a measurement is made.<ref name="Peres1993">Asher Peres, ''[[Quantum Theory: Concepts and Methods]]'', Kluwer, 1993; {{ISBN|0-7923-2549-4}} p. 115.</ref><br />
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There have been suggestions to look at the concept of time as an emergent phenomenon that is a side effect of quantum entanglement.<br />
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有人建议把时间的概念看作是量子纠缠的副作用的一种自然现象。<br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by Don Page and William Wootters in 1983.<br />
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换句话说,时间是一种纠缠现象,它将所有相同的时钟读数(正确准备的时钟,或任何可用作时钟的物体)置于同一历史中。这是唐 · 佩奇和威廉 · 伍特斯在1983年首次提出的完整理论。<br />
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As an example of entanglement: a [[subatomic particle]] [[Particle decay|decays]] into an entangled pair of other particles. The decay events obey the various [[conservation laws]], and as a result, the measurement outcomes of one daughter particle must be highly correlated with the measurement outcomes of the other daughter particle (so that the total momenta, angular momenta, energy, and so forth remains roughly the same before and after this process). For instance, a [[Spin (physics)|spin]]-zero particle could decay into a pair of spin-½ particles. Since the total spin before and after this decay must be zero (conservation of angular momentum), whenever the first particle is measured to be [[Spin (physics)#Direction|spin up]] on some axis, the other, when measured on the same axis, is always found to be [[Spin (physics)#Direction|spin down]]. (This is called the spin anti-correlated case; and if the prior probabilities for measuring each spin are equal, the pair is said to be in the [[singlet state]].)<br />
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The Wheeler–DeWitt equation that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<br />
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20世纪60年代,惠勒-德威特方程引入了广义相对论和量子力学的概念,并于1983年再次引入,当时佩奇和伍特基于量子纠缠方程提出了一个解决方案。佩奇和伍特斯认为纠缠态可以用来测量时间。<br />
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The special property of entanglement can be better observed if we separate the said two particles. Let's put one of them in the White House in Washington and the other in Buckingham Palace (think about this as a thought experiment, not an actual one). Now, if we measure a particular characteristic of one of these particles (say, for example, spin), get a result, and then measure the other particle using the same criterion (spin along the same axis), we find that the result of the measurement of the second particle will match (in a complementary sense) the result of the measurement of the first particle, in that they will be opposite in their values.<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts. The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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2013年,在意大利都灵的国家理查尔卡计量研究所(INRIM) ,研究人员对佩奇和伍特的想法进行了首次实验测试。他们的结果被解释为证实了对于内部观察者来说时间是一种涌现的现象,但正如惠勒-德威特方程所预测的那样,对于宇宙的外部观察者来说时间是不存在的。纠缠的方法是从因果时间箭头的角度出发,假设一个粒子被测量的原因决定了另一个粒子测量结果的影响。<br />
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The above result may or may not be perceived as surprising. A classical system would display the same property, and a [[hidden variable theory]] (see below) would certainly be required to do so, based on conservation of angular momentum in classical and quantum mechanics alike. The difference is that a classical system has definite values for all the observables all along, while the quantum system does not. In a sense to be discussed below, the quantum system considered here seems to acquire a probability distribution for the outcome of a measurement of the spin along any axis of the other particle upon measurement of the first particle. This probability distribution is in general different from what it would be without measurement of the first particle. This may certainly be perceived as surprising in the case of spatially separated entangled particles.<br />
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===Paradox===<br />
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Based on AdS/CFT correspondence, Mark Van Raamsdonk suggested that spacetime arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time. Induced gravity can emerge from the entanglement first law.<br />
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基于 AdS/CFT对偶的理论,Mark Van Raamsdonk 提出时空是作为量子自由度的一种涌现现象而产生的,这种量子自由度是纠缠在一起的,生活在时空的边界上。诱导引力可以产生于纠缠第一定律。<br />
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The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel [[faster than light]]) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the [[Copenhagen interpretation]], the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.<ref>{{cite book|last1=Rupert W.|first1=Anderson|title=The Cosmic Compendium: Interstellar Travel|date=28 March 2015|publisher=The Cosmic Compendium|isbn=9781329022027|page=100|edition=First|url=https://books.google.com/books?id=JxauCQAAQBAJ&pg=PA100&lpg=PA100&dq=The+outcome+is+taken+to+be+random,+with+each+possibility+having+a+probability+of+50%25.+However,+if+both+spins+are+measured+along+the+same+axis,+they+are+found+to+be+anti-correlated.+This+means+that+the+random+outcome+of+the+measurement+made+on+one+particle+seems+to+have+been+transmitted+to+the+other,+so+that+it+can+make+the+%22right+choice%22+when+it+too+is+measured#v=onepage}}</ref><br />
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The distance and timing of the measurements can be chosen so as to make the interval between the two measurements [[spacelike]], hence, any causal effect connecting the events would have to travel faster than light. According to the principles of [[special relativity]], it is not possible for any information to travel between two such measuring events. It is not even possible to say which of the measurements came first. For two spacelike separated events {{math|''x''<sub>1</sub>}} and {{math|''x''<sub>2</sub>}} there are [[inertial frame]]s in which {{math|''x''<sub>1</sub>}} is first and others in which {{math|''x''<sub>2</sub>}} is first. Therefore, the correlation between the two measurements cannot be explained as one measurement determining the other: different observers would disagree about the role of cause and effect.<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations. A well-known example is the Werner states that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables. Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<br />
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在媒体和流行科学中,量子非定域性经常被描述为等价于纠缠。虽然这对于纯二体量子态来说是正确的,但是一般来说纠缠只对于非局域关联是必要的,但是存在混合纠缠态,不产生这样的关联。一个众所周知的例子是 Werner 状态,它纠缠于 < math > p _ { sym } </math > 的某些值,但总是可以使用局部隐变量来描述。此外,研究还表明,对于任意数目的当事人,存在真正纠缠但承认局部模型的状态。<br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all distillable states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<br />
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上述关于局域模型存在性的证明假设一次只有一个量子态的副本可用。如果允许各方对这些状态的许多副本进行局部测量,那么许多表面上的局部状态(例如,量子位维尔纳状态)就不能再用局部模型来描述。对于所有的可提取态来说,情况尤其如此。然而,如果给定足够多的副本,是否所有纠缠态都成为非局域态,这仍然是一个有待解决的问题。<br />
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(In fact similar paradoxes can arise even without entanglement: the position of a single particle is spread out over space, and two widely separated detectors attempting to detect the particle in two different places must instantaneously attain appropriate correlation, so that they do not both detect the particle.)<br />
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In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to quantum teleportation and to superdense coding, whereas non-locality is defined according to experimental statistics and is much more involved with the foundations and interpretations of quantum mechanics.<br />
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简而言之,双方共享的态的纠缠是必要的,但不足以使该态成为非局域态。重要的是要认识到纠缠通常被看作是一个代数概念,因为它是非定域性以及量子遥传和超密编码的先决条件,而非定域性是根据实验统计数据定义的,更多地涉及到基础和量子力学诠释。<br />
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=== Hidden variables theory ===<br />
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A possible resolution to the paradox is to assume that quantum theory is incomplete, and the result of measurements depends on predetermined "hidden variables".<ref>{{Cite news|url=https://www.scientificamerican.com/article/cosmic-test-bolsters-einsteins-ldquo-spooky-action-at-a-distance-rdquo/?WT.mc_id=SA_FB_PHYS_NEWS|title=Cosmic Test Bolsters Einstein's "Spooky Action at a Distance"|last=magazine|first=Elizabeth Gibney, Nature|newspaper=Scientific American|language=en|access-date=2017-02-04}}</ref> The state of the particles being measured contains some [[hidden-variable theory|hidden variables]], whose values effectively determine, right from the moment of separation, what the outcomes of the spin measurements are going to be. This would mean that each particle carries all the required information with it, and nothing needs to be transmitted from one particle to the other at the time of measurement. Einstein and others (see the previous section) originally believed this was the only way out of the paradox, and the accepted quantum mechanical description (with a random measurement outcome) must be incomplete.<br />
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The following subsections are for those with a good working knowledge of the formal, mathematical description of quantum mechanics, including familiarity with the formalism and theoretical framework developed in the articles: bra–ket notation and mathematical formulation of quantum mechanics.<br />
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下面的小节适合那些对量子力学的形式和数学描述有良好工作知识的人,包括对文章中开发的形式主义和理论框架的熟悉: bra-ket 符号和量子力学的数学表述。<br />
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=== Violations of Bell's inequality ===<br />
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Local hidden variable theories fail, however, when measurements of the spin of entangled particles along different axes are considered. If a large number of pairs of such measurements are made (on a large number of pairs of entangled particles), then statistically, if the [[local realism|local realist]] or hidden variables view were correct, the results would always satisfy [[Bell's inequality]]. A [[Bell test experiments|number of experiments]] have shown in practice that Bell's inequality is not satisfied. However, prior to 2015, all of these had loophole problems that were considered the most important by the community of physicists.<ref>{{citation |author1=I. Gerhardt |author2=Q. Liu |author3=A. Lamas-Linares |author4=J. Skaar |author5=V. Scarani |author6=V. Makarov |author7=C. Kurtsiefer |year=2011 |title=Experimentally faking the violation of Bell's inequalities |journal=Phys. Rev. Lett. |volume=107 |issue=17 |page=170404 |arxiv=1106.3224 |doi=10.1103/PhysRevLett.107.170404 |bibcode=2011PhRvL.107q0404G |pmid=22107491|s2cid=16306493 }}</ref><ref>{{cite journal | last1 = Santos | first1 = E | year = 2004 | title = The failure to perform a loophole-free test of Bell's Inequality supports local realism | url = | journal = Foundations of Physics | volume = 34 | issue = 11| pages = 1643–1673 | doi=10.1007/s10701-004-1308-z|bibcode = 2004FoPh...34.1643S | s2cid = 123642560 }}</ref> When measurements of the entangled particles are made in moving [[special relativity|relativistic]] reference frames, in which each measurement (in its own relativistic time frame) occurs before the other, the measurement results remain correlated.<ref>{{cite journal |author = H. Zbinden |title = Experimental test of nonlocal quantum correlations in relativistic configurations |journal = Phys. Rev. A |volume = 63 |issue = 2 |pages = 22111 |doi = 10.1103/PhysRevA.63.022111|year = 2001|arxiv = quant-ph/0007009 |bibcode = 2001PhRvA..63b2111Z |display-authors = 1 |last2 = Gisin |last3 = Tittel |s2cid = 44611890 |url = http://archive-ouverte.unige.ch/unige:37034 }}</ref><ref name=LG>Some of the history of both referenced Zbinden, et al. experiments is provided in Gilder, L., ''The Age of Entanglement'', Vintage Books, 2008, pp. 321–324.</ref><br />
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Consider two arbitrary quantum systems and , with respective Hilbert spaces and . The Hilbert space of the composite system is the tensor product<br />
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考虑两个任意的量子系统和,分别具有希尔伯特空间和。复合系统的 Hilbert 空间是张量积<br />
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The fundamental issue about measuring spin along different axes is that these measurements cannot have definite values at the same time―they are [[Incompatible observables|incompatible]] in the sense that these measurements' maximum simultaneous precision is constrained by the [[uncertainty principle]]. This is contrary to what is found in classical physics, where any number of properties can be measured simultaneously with arbitrary accuracy. It has been proven mathematically that compatible measurements cannot show Bell-inequality-violating correlations,<ref>{{cite journal|last1=Cirel'son|first1=B. S.|title=Quantum generalizations of Bell's inequality|journal=Letters in Mathematical Physics|volume=4|issue=2|pages=93–100| year=1980|doi=10.1007/BF00417500|bibcode=1980LMaPh...4...93C|s2cid=120680226}}</ref> and thus entanglement is a fundamentally non-classical phenomenon.<br />
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<!--This paragraph is just confusing to me:<br />
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<math> H_A \otimes H_B.</math><br />
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[数学][数学]<br />
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Entanglement is required to preserve the [[Uncertainty principle]], as seen in the EPR paradox. For example, say that a high energy photon decays into an electron / positron pair, and the position of the electron and the momentum of the positron are then measured. If we don't allow entanglement in the physical description of the pair, the position and momentum of each particle can still be deduced by reference to the conservation of momentum, violating the Uncertainty principle. Alternatively, if we require the uncertainty principle to hold true, and still disallow entanglement in the physical description of the pair, the uncertainty principle would allow violations in the law of conservation of momentum, because strong correlation in both position and momentum would be impossible (i.e., one would not be able to effectively deduce the position and momentum of the electron because they could not be highly correlated with both the position and momentum of the positron).--><br />
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If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
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如果第一个系统处于状态 < math > scriptstyle | psi rangle _ a </math > ,而第二个系统处于状态 < math > scriptstyle | phi rangle _ b </math > ,则复合系统的状态为<br />
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=== Other types of experiments ===<br />
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In experiments in 2012 and 2013, polarization correlation was created between photons that never coexisted in time.<ref name="Xiao-song2012">{{cite journal |author=Xiao-song Ma, Stefan Zotter, Johannes Kofler, Rupert Ursin, Thomas Jennewein, Časlav Brukner & Anton Zeilinger |title=Experimental delayed-choice entanglement swapping |journal=Nature Physics |volume=8 |issue=6 |pages=480–485 |date=26 April 2012 |doi=10.1038/nphys2294|arxiv = 1203.4834 |bibcode = 2012NatPh...8..480M |last2=Zotter |last3=Kofler |last4=Ursin |last5=Jennewein |last6=Brukner |last7=Zeilinger |s2cid=119208488 }}</ref><ref>{{cite journal | last1 = Megidish | first1 = E. | last2 = Halevy | first2 = A. | last3 = Shacham | first3 = T. | last4 = Dvir | first4 = T. | last5 = Dovrat | first5 = L. | last6 = Eisenberg | first6 = H. S. | year = 2013 | title = Entanglement Swapping between Photons that have Never Coexisted | url = | journal = Physical Review Letters | volume = 110 | issue = 21| page = 210403| doi=10.1103/physrevlett.110.210403|arxiv = 1209.4191 |bibcode = 2013PhRvL.110u0403M | pmid=23745845| s2cid = 30063749 }}</ref> The authors claimed that this result was achieved by [[Quantum teleportation#Entanglement swapping|entanglement swapping]] between two pairs of entangled photons after measuring the polarization of one photon of the early pair, and that it proves that quantum non-locality applies not only to space but also to time.<br />
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<math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
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[数学][数学][数学]<br />
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In three independent experiments in 2013 it was shown that [[classical physics|classically communicated]] [[separable state|separable quantum states]] can be used to carry entangled states.<ref>{{cite web|url=http://physicsworld.com/cws/article/news/2013/dec/11/classical-carrier-could-create-entanglement |title=Classical carrier could create entanglement |publisher=physicsworld.com |accessdate=2014-06-14|date=2013-12-11 }}</ref> The first loophole-free Bell test was held in TU Delft in 2015 confirming the violation of Bell inequality.<ref>{{cite web | url=http://hansonlab.tudelft.nl/loophole-free-bell-test/ | title=Loophole-free Bell test &#124; Ronald Hanson | access-date=24 October 2015 | archive-url=https://web.archive.org/web/20180704082456/http://hansonlab.tudelft.nl/loophole-free-bell-test/ | archive-date=4 July 2018 | url-status=dead }}</ref><br />
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States of the composite system that can be represented in this form are called separable states, or product states.<br />
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可以用这种形式表示的复合系统状态称为可分状态或乘积状态。<br />
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In August 2014, Brazilian researcher Gabriela Barreto Lemos and team were able to "take pictures" of objects using photons that had not interacted with the subjects, but were entangled with photons that did interact with such objects. Lemos, from the University of Vienna, is confident that this new quantum imaging technique could find application where low light imaging is imperative, in fields like biological or medical imaging.<ref>{{Cite journal|url=http://www.nature.com/news/entangled-photons-make-a-picture-from-a-paradox-1.15781|title=Entangled photons make a picture from a paradox|journal=Nature|accessdate=13 October 2014|doi=10.1038/nature.2014.15781|year=2014|last1=Gibney|first1=Elizabeth|s2cid=124976589}}</ref><br />
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Not all states are separable states (and thus product states). Fix a basis <math>\scriptstyle \{|i \rangle_A\}</math> for and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for . The most general state in is of the form<br />
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并非所有状态都是可分状态(因此也就是乘积状态)。修复一个基础 < math > scriptstyle { | i rangle _ a } </math > for 和一个基础 < math > scriptstyle { | j rangle _ b } </math > for。最普遍的状态是形式<br />
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In 2015, Markus Greiner's group at Harvard performed a direct measurement of Renyi entanglement in a system of ultracold bosonic atoms.<br />
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<math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
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[数学] | psi rangle { AB } = sum { i,j } c { ij } | i rangle _ a otimes | j rangle _ b </math > 。<br />
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From 2016 various companies like IBM, Microsoft etc. have successfully created quantum computers and allowed developers and tech enthusiasts to openly experiment with concepts of quantum mechanics including quantum entanglement.<ref>{{Cite journal|last=Rozatkar|first=Gaurav|date=2018-08-16|title=Demonstration of quantum entanglement|url=https://osf.io/g8bpj/|journal=OSF|language=en}}</ref><br />
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This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
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如果存在向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > ,那么这种状态是可分的,因此 < math scriptstyle c { ij } = c ^ a _ ic ^ b _ j,</math > 产生 < math scriptstyle | psi rangle _ a = sum { i } c ^ a _ { i } | i } | i _ a </math > 和 < math > phi scriptstyle | b = sum { j } | j } | j rangle b = sum { j }。如果对于任何向量 < math > scriptstyle [ c ^ a _ i ] ,[ c ^ b _ j ] </math > 至少对于一对坐标 < math > scriptstyle c ^ a _ i,c ^ b _ j </math > 我们有 < math > scriptstyle c _ { ij } neq c ^ a _ ic ^ b _ j。如果一种状态是不可分割的,那么它被称为“纠缠态”。<br />
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=== Mystery of time ===<br />
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For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of , the following is an entangled state:<br />
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例如,给定两个基向量{ | 0 rangle _ a,| 1 rangle _ a } </math > 和两个基向量{ | 0 rangle _ b,| 1 rangle _ b } </math > ,下面是一个纠缠态:<br />
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There have been suggestions to look at the concept of time as an [[emergent phenomenon]] that is a side effect of quantum entanglement.<ref>{{Cite journal|title= Time from quantum entanglement: an experimental illustration|arxiv=1310.4691|bibcode = 2014PhRvA..89e2122M |doi = 10.1103/PhysRevA.89.052122|volume=89|issue= 5|pages=052122|journal=Physical Review A|year=2014 | last1 = Moreva | first1 = Ekaterina|s2cid=118638346}}</ref><ref>{{cite web|url=https://www.newscientist.com/article/dn24473-entangled-toy-universe-shows-time-may-be-an-illusion.html#.U8_-ApSSx2A|title=Entangled toy universe shows time may be an illusion|publisher=|accessdate=13 October 2014}}</ref><br />
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In other words, time is an entanglement phenomenon, which places all equal clock readings (of correctly prepared clocks, or of any objects usable as clocks) into the same history. This was first fully theorized by [[Don Page (physicist)|Don Page]] and [[William Wootters]] in 1983.<ref>David Deutsch, The Beginning of infinity. Page 299</ref><br />
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<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
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左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right)<br />
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The [[Wheeler–DeWitt equation]] that combines general relativity and quantum mechanics – by leaving out time altogether – was introduced in the 1960s and it was taken up again in 1983, when Page and Wootters made a solution based on quantum entanglement. Page and Wootters argued that entanglement can be used to measure time.<ref name="medium.com">{{cite web|url=https://medium.com/the-physics-arxiv-blog/quantum-experiment-shows-how-time-emerges-from-entanglement-d5d3dc850933|title=Quantum Experiment Shows How Time 'Emerges' from Entanglement|website=Medium|accessdate=13 October 2014|date=2013-10-23}}</ref><br />
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If the composite system is in this state, it is impossible to attribute to either system or system a definite pure state. Another way to say this is that while the von Neumann entropy of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry. The above example is one of four Bell states, which are (maximally) entangled pure states (pure states of the space, but which cannot be separated into pure states of each and ).<br />
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如果组合系统处于这种状态,就不可能给任何一个系统或系统一个确定的纯状态。另一种说法是,尽管整个状态的冯纽曼熵为零(对于任何纯状态都是如此) ,但子系统的熵大于零。从这个意义上说,这两个系统是“纠缠”的。这对干涉测量法有具体的经验影响。上面的例子是四个贝尔态之一,它们是(最大)纠缠纯态(空间的纯态,但不能分离成每个和的纯态)。<br />
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In 2013, at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, researchers performed the first experimental test of Page and Wootters' ideas. Their result has been interpreted{{by whom|date=August 2020}} to confirm that time is an emergent phenomenon for internal observers but absent for external observers of the universe just as the Wheeler-DeWitt equation predicts.<ref name="medium.com"/><br />
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Now suppose Alice is an observer for system , and Bob is an observer for system . If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of , there are two possible outcomes, occurring with equal probability:<br />
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现在假设 Alice 是系统的观察者,而 Bob 是系统的观察者。如果在上面给出的纠缠态中,爱丽丝在[ | 0 rangle,| 1 rangle ] </math 本征基中进行测量,有两种可能的结果,发生的概率相等:<br />
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=== Source for the arrow of time ===<br />
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Physicist [[Seth Lloyd]] says that [[quantum uncertainty]] gives rise to entanglement, the putative source of the [[arrow of time]]. According to Lloyd; "The arrow of time is an arrow of increasing correlations."<ref>{{Cite journal|url=https://www.wired.com/2014/04/quantum-theory-flow-time/|title=New Quantum Theory Could Explain the Flow of Time|journal=Wired|accessdate=13 October 2014|date=2014-04-25|last1=Wolchover|first1=Natalie}}</ref> The approach to entanglement would be from the perspective of the causal arrow of time, with the assumption that the cause of the measurement of one particle determines the effect of the result of the other particle's measurement.<br />
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Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
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Alice 测量0,系统的状态崩溃为 < math > scriptstyle | 0 rangle _ a | 1 rangle _ b </math > 。<br />
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Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
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Alice 测量1,系统的状态崩溃为 < math > scriptstyle | 1 rangle _ a | 0 rangle _ b </math > 。<br />
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=== Emergent gravity ===<br />
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If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system has been altered by Alice performing a local measurement on system . This remains true even if the systems and are spatially separated. This is the foundation of the EPR paradox.<br />
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如果前者发生,那么 Bob 在相同基础上执行的任何后续测量都将返回1。如果出现后一种情况,(Alice 度量1) ,那么 Bob 的度量将确定返回0。因此,Alice 对系统进行了本地测量,从而对系统进行了更改。即使系统和空间上是分开的,这也是正确的。这就是 EPR 悖论的基础。<br />
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Based on [[AdS/CFT correspondence]], [[Mark Van Raamsdonk]] suggested that [[spacetime]] arises as an emergent phenomenon of the quantum degrees of freedom that are entangled and live in the boundary of the space-time.<ref>{{Cite journal|last=Van Raamsdonk|first=Mark|date=2010-06-19|title=Building up spacetime with quantum entanglement|journal=General Relativity and Gravitation|language=en|volume=42|issue=10|pages=2323–2329|doi=10.1007/s10714-010-1034-0|issn=0001-7701|arxiv=1005.3035|bibcode=2010GReGr..42.2323V}}</ref> [[Induced gravity]] can emerge from the entanglement first law.<ref>{{Cite journal|last1=Lee|first1=Jae-Weon|last2=Kim|first2=Hyeong-Chan|last3=Lee|first3=Jungjai|date=2013|title=Gravity from quantum information|journal=Journal of the Korean Physical Society|language=en|volume=63|issue=5|pages=1094–1098|doi=10.3938/jkps.63.1094|issn=0374-4884|arxiv=1001.5445|bibcode=2013JKPS...63.1094L|s2cid=118494859}}</ref><ref>{{cite arxiv|last1=Swingle|first1=Brian|last2=Van Raamsdonk|first2=Mark|date=2014-05-12|title=Universality of Gravity from Entanglement|eprint=1405.2933 |class=hep-th}}</ref><br />
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The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see no-communication theorem.<br />
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爱丽丝的测量结果是随机的。Alice 不能决定将组合系统折叠到哪个状态,因此不能通过作用于她的系统将信息传递给 Bob。因此,在这个特定的方案中,因果关系被保留了下来。关于一般的论点,请参阅不交流定理。<br />
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== Non-locality and entanglement ==<br />
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In the media and popular science, quantum non-locality is often portrayed as being equivalent to entanglement. While this is true for pure bipartite quantum states, in general entanglement is only necessary for non-local correlations, but there exist mixed entangled states that do not produce such correlations.<ref name="Brunner-RMP2014">{{cite journal |title=Bell nonlocality |author1=Nicolas Brunner |author2=Daniel Cavalcanti |author3=Stefano Pironio |author4=Valerio Scarani |author5=Stephanie Wehner |journal=Rev. Mod. Phys. |volume=86 |issue=2 |pages=419–478 |date=2014 |doi=10.1103/RevModPhys.86.419 |arxiv=1303.2849|bibcode=2014RvMP...86..419B |s2cid=119194006 }}</ref> A well-known example is the [[Werner state]]s that are entangled for certain values of <math>p_{sym}</math>, but can always be described using local hidden variables.<ref name=werner1989>{{cite journal | last = Werner| first = R.F. | title = Quantum States with Einstein-Podolsky-Rosen correlations admitting a hidden-variable model | journal = [[Physical Review A]] | volume = 40| pages = 4277–4281 | year = 1989 |doi=10.1103/PhysRevA.40.4277 | pmid=9902666 | issue=8|bibcode = 1989PhRvA..40.4277W }}</ref> Moreover, it was shown that, for arbitrary numbers of parties, there exist states that are genuinely entangled but admit a local model.<ref>{{cite journal|author=R. Augusiak, M. Demianowicz, J. Tura and A. Acín |title=Entanglement and Nonlocality are Inequivalent for Any Number of Parties |journal=Phys. Rev. Lett. |volume=115 |issue=3 |pages=030404 |year=2015 |arxiv=1407.3114 |doi=10.1103/PhysRevLett.115.030404|pmid=26230773 |hdl=2117/78836 |bibcode=2015PhRvL.115c0404A |s2cid=29758483 }}</ref><br />
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The mentioned proofs about the existence of local models assume that there is only one copy of the quantum state available at a time. If the parties are allowed to perform local measurements on many copies of such states, then many apparently local states (e.g., the qubit Werner states) can no longer be described by a local model. This is, in particular, true for all [[entanglement distillation|distillable]] states. However, it remains an open question whether all entangled states become non-local given sufficiently many copies.<ref>{{cite journal |title=Disproving the Peres conjecture: Bell nonlocality from bipartite bound entanglement |authors=Tamas Vértesi, Nicolas Brunner|year=2014 |journal=Nature Communications |volume=5 |issue=5297|page=5297 |doi=10.1038/ncomms6297 |pmid=25370352|arxiv=1405.4502 |s2cid=5135148}}</ref><br />
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As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a density matrix, which is a positive-semidefinite matrix, or a trace class when the state space is infinite-dimensional, and has trace 1. Again, by the spectral theorem, such a matrix takes the general form:<br />
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如上所述,量子系统的状态是由希尔伯特空间中的单位向量给出的。更一般地说,如果一个人对系统的了解较少,那么他就称之为“集合” ,并用密度矩阵来描述它,密度矩阵是正半定矩阵,或者当状态空间是无限维且迹1时,用迹类来描述它。同样的,在谱定理,这样的矩阵采取了一般的形式:<br />
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<br />
<br />
In short, entanglement of a state shared by two parties is necessary but not sufficient for that state to be non-local. It is important to recognize that entanglement is more commonly viewed as an algebraic concept, noted for being a prerequisite to non-locality as well as to [[quantum teleportation]] and to [[superdense coding]], whereas non-locality is defined according to experimental statistics and is much more involved with the [[Quantum foundations|foundations]] and [[interpretations of quantum mechanics]].<ref>In the literature "non-locality" is sometimes used to characterize concepts that differ from the non-existence of a local hidden variable model, e.g., whether states can be distinguished by local measurements and which can occur also for non-entangled states (see, e.g., {{cite journal |authors=Charles H. Bennett, David P. DiVincenzo, Christopher A. Fuchs, Tal Mor, Eric Rains, Peter W. Shor, John A. Smolin, and William K. Wootters |title=Quantum nonlocality without entanglement |journal=Phys. Rev. A |volume=59 |issue=2 |pages=1070–1091 |year=1999 |doi=10.1103/PhysRevA.59.1070 |arxiv= quant-ph/9804053|bibcode=1999PhRvA..59.1070B |s2cid=15282650 }}). This non-standard use of the term is not discussed here.</ref><br />
<br />
<math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
我不知道,我不知道,我不知道<br />
<br />
<br />
<br />
== Quantum mechanical framework ==<br />
<br />
where the w<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret as representing an ensemble where is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need density matrices to represent the state.<br />
<br />
其中 w < sub > i </sub > 是正值概率(和为1) ,向量是单位向量,在无限维情况下,我们取这些状态的闭包为迹范数。我们可以解释为代表一个集合,其中集合的状态是 < math > | alpha _ i rangle </math > 。当一个混合状态的秩为1时,它就描述了一个纯系综。当量子系统的状态信息少于总量时,我们需要密度矩阵来表示状态。<br />
<br />
The following subsections are for those with a good working knowledge of the formal, mathematical description of [[quantum mechanics]], including familiarity with the formalism and theoretical framework developed in the articles: [[bra–ket notation]] and [[mathematical formulation of quantum mechanics]].<br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits electrons towards an observer. The electrons' Hilbert spaces are identical. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with spins aligned in the positive direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
在实验上,可以实现如下的混合集成。考虑一个“黑盒子”装置,它向观察者喷射电子。电子的希尔伯特空间是相同的。该装置可能产生全部处于相同状态的电子; 在这种情况下,观察者接收到的电子就是一个纯系综。然而,这种装置可以在不同的状态下产生电子。例如,它可以产生两个电子群: 一个是状态 < math > | mathbf { z } + rangle </math > 的正方向自旋,另一个是状态 < math > | mathbf { y }-rangle </math > 的负方向自旋。通常,这是一个混合集合,因为可以有任意数量的总体,每个总体对应不同的状态。<br />
<br />
=== Pure states ===<br />
<br />
Consider two arbitrary quantum systems {{mvar|A}} and {{mvar|B}}, with respective [[Hilbert space]]s {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}. The Hilbert space of the composite system is the [[tensor product]]<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on . That is, it has the general form<br />
<br />
根据上面的定义,对于二部复合系统,混合态仅仅是上面的密度矩阵。也就是说,它有一般的形式<br />
<br />
<br />
<br />
: <math> H_A \otimes H_B.</math><br />
<br />
<math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
[数学] rho = sum { i } w _ i 左[ sum _ { j } bar { c }{ ij }(| alpha _ { ij } rangle otimes | beta _ { ij } rangle)右]左[ sum _ k c _ { ik }(langle alpha _ ik } | otimes langle beta _ { ik } | 右]<br />
<br />
<br />
<br />
</math><br />
<br />
数学<br />
<br />
If the first system is in state <math>\scriptstyle| \psi \rangle_A</math> and the second in state <math>\scriptstyle| \phi \rangle_B</math>, the state of the composite system is<br />
<br />
<br />
<br />
where the w<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
其中 w < sub > i </sub > 是正值概率,< math > sum _ j | c _ { ij } | ^ 2 = 1 </math > ,向量是单位向量。这是自伴和正的,并且有迹1。<br />
<br />
: <math>|\psi\rangle_A \otimes |\phi\rangle_B.</math><br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<br />
<br />
从纯粹情形扩展可分性的定义,我们说混合状态是可分的,如果它可以写成<br />
<br />
States of the composite system that can be represented in this form are called [[separable state]]s, or [[product state]]s.<br />
<br />
<br />
<br />
<math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
(数学) rho = sum i w i rho i ^ a times rho i ^ b,(数学)<br />
<br />
Not all states are separable states (and thus product states). Fix a [[basis (linear algebra)|basis]] <math>\scriptstyle \{|i \rangle_A\}</math> for {{mvar|H<sub>A</sub>}} and a basis <math>\scriptstyle \{|j \rangle_B\}</math> for {{mvar|H<sub>B</sub>}}. The most general state in {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} is of the form<br />
<br />
<br />
<br />
where the are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems and respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
其中的正值概率和 rho _ i ^ a </math > 的和 rho _ i ^ b </math > 的本身是子系统和子系统上的混合状态(密度算符)。换句话说,如果一个状态是不相关状态或乘积状态上的概率分布,则该状态是可分的。通过将密度矩阵写成纯系综和并进行扩展,我们可以假定,不失一般性和数学本身就是纯系综。如果一个状态不可分离,则称其为纠缠态。<br />
<br />
: <math>|\psi\rangle_{AB} = \sum_{i,j} c_{ij} |i\rangle_A \otimes |j\rangle_B</math>.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be NP-hard. For the and cases, a necessary and sufficient criterion for separability is given by the famous Positive Partial Transpose (PPT) condition.<br />
<br />
一般来说,要判断一个混合态是否是纠缠态是很困难的。一般的二部格被证明是 np 困难的。对于和种情形,利用著名的正偏转子(PPT)条件给出了可分性的一个充要条件。<br />
<br />
This state is separable if there exist vectors <math>\scriptstyle [c^A_i], [c^B_j]</math> so that <math>\scriptstyle c_{ij}= c^A_ic^B_j,</math> yielding <math>\scriptstyle |\psi\rangle_A = \sum_{i} c^A_{i} |i\rangle_A</math> and <math>\scriptstyle |\phi\rangle_B = \sum_{j} c^B_{j} |j\rangle_B.</math> It is inseparable if for any vectors <math>\scriptstyle [c^A_i],[c^B_j]</math> at least for one pair of coordinates <math>\scriptstyle c^A_i,c^B_j</math> we have <math>\scriptstyle c_{ij} \neq c^A_ic^B_j.</math> If a state is inseparable, it is called an 'entangled state'.<br />
<br />
<br />
<br />
For example, given two basis vectors <math>\scriptstyle \{|0\rangle_A, |1\rangle_A\}</math> of {{mvar|H<sub>A</sub>}} and two basis vectors <math>\scriptstyle \{|0\rangle_B, |1\rangle_B\}</math> of {{mvar|H<sub>B</sub>}}, the following is an entangled state:<br />
<br />
The idea of a reduced density matrix was introduced by Paul Dirac in 1930. Consider as above systems and each with a Hilbert space . Let the state of the composite system be<br />
<br />
约化密度矩阵的概念是由保罗 · 狄拉克在1930年提出的。考虑以上系统,每个系统都有一个希尔伯特空间。设复合系统的状态为<br />
<br />
<br />
<br />
: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right ).</math><br />
<br />
<math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
<br />
[数学] | Psi 在 h _ a 和 h _ b 之间。数学<br />
<br />
<br />
<br />
If the composite system is in this state, it is impossible to attribute to either system {{mvar|A}} or system {{mvar|B}} a definite [[pure state]]. Another way to say this is that while the [[von Neumann entropy]] of the whole state is zero (as it is for any pure state), the entropy of the subsystems is greater than zero. In this sense, the systems are "entangled". This has specific empirical ramifications for interferometry.<ref name="JaegerEtAl95">{{cite journal |author=Jaeger G, Shimony A, Vaidman L |title=Two Interferometric Complementarities |journal=Phys. Rev. |volume=51 |issue=1 |pages=54–67 |year=1995 |doi=10.1103/PhysRevA.51.54|pmid=9911555 |bibcode = 1995PhRvA..51...54J |last2=Shimony |last3=Vaidman }}</ref> The above example is one of four [[Bell states]], which are (maximally) entangled pure states (pure states of the {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}} space, but which cannot be separated into pure states of each {{mvar|H<sub>A</sub>}} and {{mvar|H<sub>B</sub>}}).<br />
<br />
As indicated above, in general there is no way to associate a pure state to the component system . However, it still is possible to associate a density matrix. Let<br />
<br />
如上所述,通常没有办法将纯状态关联到组件系统。然而,仍然有可能将密度矩阵联系起来。让<br />
<br />
<br />
<br />
Now suppose Alice is an observer for system {{mvar|A}}, and Bob is an observer for system {{mvar|B}}. If in the entangled state given above Alice makes a measurement in the <math>\scriptstyle \{|0\rangle, |1\rangle\}</math> eigenbasis of {{mvar|A}}, there are two possible outcomes, occurring with equal probability:<ref name=nielchuang>{{cite book| last = Nielsen | first = Michael A. |author2=Chuang, Isaac L. | year = 2000 | title = Quantum Computation and Quantum Information | publisher = [[Cambridge University Press]] | pages = 112–113| isbn = 978-0-521-63503-5}}</ref><br />
<br />
<math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
<br />
我不知道,我不知道,我不知道。<br />
<br />
<br />
<br />
# Alice measures 0, and the state of the system collapses to <math>\scriptstyle |0\rangle_A |1\rangle_B</math>.<br />
<br />
which is the projection operator onto this state. The state of is the partial trace of over the basis of system :<br />
<br />
也就是这个状态的投影操作符。状态是系统基础上的部分轨迹:<br />
<br />
# Alice measures 1, and the state of the system collapses to <math>\scriptstyle |1\rangle_A |0\rangle_B</math>.<br />
<br />
<br />
<br />
<math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
<br />
(| Psi rangle langle Psi | right) | j rangle b = hbox { Tr } _ b; rho _ t. </math > <br />
<br />
If the former occurs, then any subsequent measurement performed by Bob, in the same basis, will always return 1. If the latter occurs, (Alice measures 1) then Bob's measurement will return 0 with certainty. Thus, system {{mvar|B}} has been altered by Alice performing a local measurement on system {{mvar|A}}. This remains true even if the systems {{mvar|A}} and {{mvar|B}} are spatially separated. This is the foundation of the [[EPR paradox]].<br />
<br />
<br />
<br />
is sometimes called the reduced density matrix of on subsystem . Colloquially, we "trace out" system to obtain the reduced density matrix on .<br />
<br />
有时被称为子系统的约化密度矩阵。通俗地说,我们“追踪”系统,以获得约化密度矩阵。<br />
<br />
The outcome of Alice's measurement is random. Alice cannot decide which state to collapse the composite system into, and therefore cannot transmit information to Bob by acting on her system. Causality is thus preserved, in this particular scheme. For the general argument, see [[no-communication theorem]].<br />
<br />
<br />
<br />
For example, the reduced density matrix of for the entangled state<br />
<br />
例如,纠缠态的约化密度矩阵<br />
<br />
=== Ensembles ===<br />
<br />
As mentioned above, a state of a quantum system is given by a unit vector in a Hilbert space. More generally, if one has less information about the system, then one calls it an 'ensemble' and describes it by a [[density matrix]], which is a [[positive-semidefinite matrix]], or a [[trace class]] when the state space is infinite-dimensional, and has trace 1. Again, by the [[spectral theorem]], such a matrix takes the general form:<br />
<br />
<math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
<br />
左(| 0 rangle _ a otimes | 1 rangle _ b-| 1 rangle _ a otimes | 0 rangle _ b right) ,</math > <br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i |\alpha_i\rangle \langle\alpha_i|,</math><br />
<br />
discussed above is<br />
<br />
以上所讨论的是<br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positive-valued probabilities (they sum up to 1), the vectors {{mvar| α<sub>i</sub>}} are unit vectors, and in the infinite-dimensional case, we would take the closure of such states in the trace norm. We can interpret {{mvar|ρ}} as representing an ensemble where {{mvar|w<sub>i</sub>}} is the proportion of the ensemble whose states are <math>|\alpha_i\rangle</math>. When a mixed state has rank 1, it therefore describes a 'pure ensemble'. When there is less than total information about the state of a quantum system we need [[#Reduced density matrices|density matrices]] to represent the state.<br />
<br />
<math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
<br />
左(| 0 rangle 0 | a + | 1 rangle 1 | a right) </math > <br />
<br />
<br />
<br />
Experimentally, a mixed ensemble might be realized as follows. Consider a "black box" apparatus that spits [[electron]]s towards an observer. The electrons' Hilbert spaces are [[identical particles|identical]]. The apparatus might produce electrons that are all in the same state; in this case, the electrons received by the observer are then a pure ensemble. However, the apparatus could produce electrons in different states. For example, it could produce two populations of electrons: one with state <math>|\mathbf{z}+\rangle</math> with [[spin (physics)|spins]] aligned in the positive {{math|'''z'''}} direction, and the other with state <math>|\mathbf{y}-\rangle</math> with spins aligned in the negative {{math|'''y'''}} direction. Generally, this is a mixed ensemble, as there can be any number of populations, each corresponding to a different state.<br />
<br />
This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
<br />
这表明,正如预期的那样,一个纠缠纯系综的约化密度矩阵是一个混合系综。同样不足为奇的是,上面讨论的纯乘积态的密度矩阵<br />
<br />
<br />
<br />
Following the definition above, for a bipartite composite system, mixed states are just density matrices on {{math|''H<sub>A</sub>'' ⊗ ''H<sub>B</sub>''}}. That is, it has the general form<br />
<br />
<math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
<br />
我不知道,但是我知道,我知道。<br />
<br />
<br />
<br />
: <math>\rho =\sum_{i} w_i\left[\sum_{j} \bar{c}_{ij} (|\alpha_{ij}\rangle\otimes|\beta_{ij}\rangle)\right]\left[\sum_k c_{ik} (\langle\alpha_{ik}|\otimes\langle\beta_{ik}|)\right]<br />
<br />
In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
<br />
一般情况下,二体纯态 ρ 纠缠当且仅当其约化态是混合态而不是纯态。<br />
<br />
</math><br />
<br />
<br />
<br />
where the ''w''<sub>i</sub> are positively valued probabilities, <math>\sum_j |c_{ij}|^2=1</math>, and the vectors are unit vectors. This is self-adjoint and positive and has trace 1.<br />
<br />
Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional AKLT spin chain: the ground state can be divided into a block and an environment. The reduced density matrix of the block is proportional to a projector to a degenerate ground state of another Hamiltonian.<br />
<br />
在不同的基态自旋链中显式计算了约化密度矩阵。一维 AKLT 自旋链就是一个例子: 基态可以分为一个区块和一个环境。块的约化密度矩阵与另一个哈密顿量的简并基态成正比。<br />
<br />
<br />
<br />
Extending the definition of separability from the pure case, we say that a mixed state is separable if it can be written as<ref name=Laloe>{{citation|last=Laloe|first=Franck|year=2001|title=Do We Really Understand Quantum Mechanics|journal=American Journal of Physics |volume=69 |issue=6|pages=655–701 |arxiv=quant-ph/0209123 |bibcode=2001AmJPh..69..655L |doi=10.1119/1.1356698}}</ref>{{rp|131–132}}<br />
<br />
The reduced density matrix also was evaluated for XY spin chains, where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence in this case.<br />
<br />
并对 XY 自旋链的全秩约化密度矩阵进行了计算。证明了在热力学极限中,大块自旋的约化密度矩阵的谱在这种情况下是一个精确的几何序列。<br />
<br />
<br />
<br />
: <math>\rho = \sum_i w_i \rho_i^A \otimes \rho_i^B, </math><br />
<br />
<br />
<br />
In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary quantum operations can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called LOCC (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<br />
<br />
在量子信息理论中,纠缠态被认为是一种“资源” ,即制造成本高昂的物质,并且可以实现有价值的转换。这种观点最为明显的背景是“遥远的实验室” ,即两个标记为“ a”和“ b”的量子系统,其中每个系统都可以执行任意的量子操作,但它们之间不存在量子力学相互作用。唯一允许的相互作用是经典信息的交换,它与最一般的局部量子操作相结合,产生了一类称为 LOCC 的操作(局部操作和经典通信)。这些操作不允许在系统 a 和系统 b 之间产生纠缠态。但是如果给 a 和 b 提供了纠缠态,那么这些纠缠态和 LOCC 操作一起可以产生更大类的变换。例如,a 的一个量子比特和 b 的一个量子比特之间的相互作用可以通过首先将 a 的量子比特传送到 b,然后让 b 的量子比特和 b 的量子比特相互作用(这现在是一个 LOCC 操作,因为两个量子比特都在 b 的实验室里) ,然后再传送量子比特回到 a。两个量子比特的最大纠缠态在这个过程中被用完。因此,纠缠态是一种资源,它能够在只有 LOCC 可用的情况下实现量子相互作用(或量子通道) ,但是在这个过程中会被消耗掉。在其他应用中,纠缠态可以被看作是一种资源,例如,私人通信或者区分量子态。<br />
<br />
where the {{mvar|w<sub>i</sub>}} are positively valued probabilities and the <math>\rho_i^A</math>'s and <math>\rho_i^B</math>'s are themselves mixed states (density operators) on the subsystems {{mvar|A}} and {{mvar|B}} respectively. In other words, a state is separable if it is a probability distribution over uncorrelated states, or product states. By writing the density matrices as sums of pure ensembles and expanding, we may assume without loss of generality that <math>\rho_i^A</math> and <math>\rho_i^B</math> are themselves pure ensembles. A state is then said to be entangled if it is not separable.<br />
<br />
<br />
<br />
In general, finding out whether or not a mixed state is entangled is considered difficult. The general bipartite case has been shown to be [[NP-hard]].<ref>{{Cite book |author=Gurvits L |title=Proceedings of the thirty-fifth ACM symposium on Theory of computing - STOC '03 |chapter=Classical deterministic complexity of Edmonds' Problem and quantum entanglement |journal=Proceedings of the Thirty-fifth Annual ACM Symposium on Theory of Computing |year=2003 |doi=10.1145/780542.780545 |page=10 |isbn=978-1-58113-674-6|arxiv=quant-ph/0303055 |s2cid=5745067 }}</ref> For the {{math|2 × 2}} and {{math|2 × 3}} cases, a necessary and sufficient criterion for separability is given by the famous [[Peres-Horodecki criterion|Positive Partial Transpose (PPT)]] condition.<ref>{{cite journal |author=Horodecki M, Horodecki P, Horodecki R |title=Separability of mixed states: necessary and sufficient conditions |journal=Physics Letters A |volume=223 |issue=1 |page=210 |year=1996 |doi=10.1016/S0375-9601(96)00706-2 |bibcode=1996PhLA..223....1H|arxiv = quant-ph/9605038 |last2=Horodecki |last3=Horodecki |citeseerx=10.1.1.252.496 |s2cid=10580997 }}</ref><br />
<br />
<br />
<br />
=== Reduced density matrices ===<br />
<br />
In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
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在这一节中,我们将讨论混合态的熵,以及如何将其视为量子纠缠的度量。<br />
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The idea of a reduced density matrix was introduced by [[Paul Dirac]] in 1930.<ref>{{cite journal|doi=10.1017/S0305004100016108|title=Note on Exchange Phenomena in the Thomas Atom|year=2008|last1=Dirac|first1=P. A. M.|journal=Mathematical Proceedings of the Cambridge Philosophical Society| volume=26| issue=3|page=376|bibcode=1930PCPS...26..376D|url=https://www.cambridge.org/core/services/aop-cambridge-core/content/view/6C5FF7297CD96F49A8B8E9E3EA50E412/S0305004100016108a.pdf/div-class-title-note-on-exchange-phenomena-in-the-thomas-atom-div.pdf}}</ref> Consider as above systems {{mvar|A}} and {{mvar|B}} each with a Hilbert space {{mvar|H<sub>A</sub>, H<sub>B</sub>}}. Let the state of the composite system be<br />
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: <math> |\Psi \rangle \in H_A \otimes H_B. </math><br />
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The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.<br />
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二分子2能级纯态的冯纽曼熵与本征值的图。当本征值为5时,冯纽曼熵处于最大值,相当于最大纠缠度。<br />
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In classical information theory , the Shannon entropy, is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<br />
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在经典的信息论中,香农熵,是与概率分布相关联的,如下:<br />
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As indicated above, in general there is no way to associate a pure state to the component system {{mvar|A}}. However, it still is possible to associate a density matrix. Let<br />
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<math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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[ math ] h (p _ 1,cdots,p _ n) =-sum _ i p _ i log _ 2 p _ i. [ math ]<br />
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: <math>\rho_T = |\Psi\rangle \; \langle\Psi|</math>.<br />
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Since a mixed state is a probability distribution over an ensemble, this leads naturally to the definition of the von Neumann entropy:<br />
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由于混合状态是一个概率分布超过一个总体,这自然导致了冯纽曼熵的定义:<br />
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which is the [[projection operator]] onto this state. The state of {{mvar|A}} is the [[partial trace]] of {{mvar|ρ<sub>T</sub>}} over the basis of system {{mvar|B}}:<br />
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<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
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(rho) =-hbox { Tr } left (rho log _ 2{ rho } right) <br />
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: <math>\rho_A \ \stackrel{\mathrm{def}}{=}\ \sum_j \langle j|_B \left( |\Psi\rangle \langle\Psi| \right) |j\rangle_B = \hbox{Tr}_B \; \rho_T.</math><br />
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In general, one uses the Borel functional calculus to calculate a non-polynomial function such as . If the nonnegative operator acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
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一般来说,人们使用 Borel 函数演算来计算一个非多项式函数,如。如果非负算子作用于有限维希尔伯特空间,并且具有本征值 < math > lambda _ 1,那么 cdots,lambda _ n </math > ,结果只不过是具有相同本征向量的算子,但本征值 < math > log _ 2(lambda _ 1) ,点,log _ 2(lambda _ n) </math > 。那么香农熵就是:<br />
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{{mvar|ρ<sub>A</sub>}} is sometimes called the reduced density matrix of {{mvar|ρ}} on subsystem {{mvar|A}}. Colloquially, we "trace out" system {{mvar|B}} to obtain the reduced density matrix on {{mvar|A}}.<br />
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<math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
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(rho) =-hbox { Tr } left (rho log 2{ rho } right) =-sum _ i lambda _ i log _ 2 lambda _ i </math > .<br />
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For example, the reduced density matrix of {{mvar|A}} for the entangled state<br />
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Since an event of probability 0 should not contribute to the entropy, and given that<br />
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因为一个概率为0的事件不应该对熵有贡献,并且假设<br />
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: <math>\tfrac{1}{\sqrt{2}} \left ( |0\rangle_A \otimes |1\rangle_B - |1\rangle_A \otimes |0\rangle_B \right),</math><br />
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<math> \lim_{p \to 0} p \log p = 0,</math><br />
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[ math > lim _ { p to 0} p log p = 0,</math > <br />
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discussed above is<br />
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the convention 0}} is adopted. This extends to the infinite-dimensional case as well: if has spectral resolution<br />
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约定0}被采用。这也延伸到无限维情况: 如果有光谱分辨率<br />
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: <math>\rho_A = \tfrac{1}{2} \left ( |0\rangle_A \langle 0|_A + |1\rangle_A \langle 1|_A \right )</math><br />
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<math> \rho = \int \lambda d P_{\lambda},</math><br />
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数学,数学,数学<br />
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This demonstrates that, as expected, the reduced density matrix for an entangled pure ensemble is a mixed ensemble. Also not surprisingly, the density matrix of {{mvar|A}} for the pure product state <math>|\psi\rangle_A \otimes |\phi\rangle_B</math> discussed above is<br />
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assume the same convention when calculating<br />
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在计算时采用相同的约定<br />
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: <math>\rho_A = |\psi\rangle_A \langle\psi|_A</math>.<br />
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<math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
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[数学] rho log 2 rho = int lambda log 2 lambda d { lambda }<br />
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In general, a bipartite pure state ρ is entangled if and only if its reduced states are mixed rather than pure.<br />
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As in statistical mechanics, the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is (which can be shown to be the maximum entropy for mixed states).<br />
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就像统计力学一样,系统的不确定性(微观状态的数量)越多,熵就越大。例如,任何纯态的熵都为零,这并不奇怪,因为处于纯态的系统没有不确定性。上面讨论的纠缠态的两个子系统中的任何一个的熵都是(混合态的最大熵)。<br />
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=== Two applications that use them ===<br />
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Reduced density matrices were explicitly calculated in different spin chains with unique ground state. An example is the one-dimensional [[AKLT Model|AKLT spin chain]]:<ref name="Fan2004">{{cite journal | doi = 10.1103/PhysRevLett.93.227203 | title = Entanglement in a Valence-Bond Solid State | journal = Physical Review Letters | year = 2004 | first = H | last = Fan | page = 227203 |author2=Korepin V |author3=Roychowdhury V | volume = 93 | issue = 22 | pmid = 15601113 |arxiv=quant-ph/0406067 | bibcode=2004PhRvL..93v7203F| s2cid = 28587190 }}</ref> the ground state can be divided into a block and an environment. The reduced density matrix of the block is [[Proportionality (mathematics)|proportional]] to a projector to a degenerate ground state of another Hamiltonian.<br />
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Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist. If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
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熵提供了一个可以用来量化纠缠的工具,尽管还存在其他的纠缠度量方法。如果整个系统是纯系统,则可以用一个子系统的熵来衡量其与其他子系统的纠缠程度。<br />
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The reduced density matrix also was evaluated for [[Heisenberg model (quantum)|XY spin chains]], where it has full rank. It was proved that in the thermodynamic limit, the spectrum of the reduced density matrix of a large block of spins is an exact geometric sequence<ref>{{cite journal| doi=10.1007/s11128-010-0197-7|arxiv=1002.2931|title=Spectrum of the density matrix of a large ''block of'' spins of the XY model in one dimension| year=2010|last1=Franchini|first1=F.|last2=Its|first2=A. R.|last3=Korepin|first3=V. E.|last4=Takhtajan|first4=L. A.|journal=Quantum Information Processing|volume=10|issue=3|pages=325–341|s2cid=6683370}}</ref> in this case.<br />
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For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
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对于两体纯态,减少态的冯纽曼熵是唯一的纠缠度量,因为它是满足纠缠度量所要求的特定公理的态家族中唯一的函数。<br />
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=== Entanglement as a resource ===<br />
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In quantum information theory, entangled states are considered a 'resource', i.e., something costly to produce and that allows to implement valuable transformations. The setting in which this perspective is most evident is that of "distant labs", i.e., two quantum systems labeled "A" and "B" on each of which arbitrary [[quantum operation]]s can be performed, but which do not interact with each other quantum mechanically. The only interaction allowed is the exchange of classical information, which combined with the most general local quantum operations gives rise to the class of operations called [[LOCC]] (local operations and classical communication). These operations do not allow the production of entangled states between the systems A and B. But if A and B are provided with a supply of entangled states, then these, together with LOCC operations can enable a larger class of transformations. For example, an interaction between a qubit of A and a qubit of B can be realized by first teleporting A's qubit to B, then letting it interact with B's qubit (which is now a LOCC operation, since both qubits are in B's lab) and then teleporting the qubit back to A. Two maximally entangled states of two qubits are used up in this process. Thus entangled states are a resource that enables the realization of quantum interactions (or of quantum channels) in a setting where only LOCC are available, but they are consumed in the process. There are other applications where entanglement can be seen as a resource, e.g., private communication or distinguishing quantum states.<ref name="horodecki2007" /><br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/n,...,1/n}. Therefore, a bipartite pure state is said to be a maximally entangled state if the reduced state of is the diagonal matrix<br />
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一个经典的结果是,香农熵在均匀概率分布{1/n,... ,1/n }处达到最大值。因此,如果二分纯态的约化态是对角矩阵,则称二分纯态为最大纠缠态<br />
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=== Classification of entanglement ===<br />
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<math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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< math > begin { bmatrix } frac {1}{ n } & & ddots & frac {1}{ n } end { bmatrix } . </math > <br />
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Not all quantum states are equally valuable as a resource. To quantify this value, different [[Quantum entanglement#Entanglement measures|entanglement measures]] (see below) can be used, that assign a numerical value to each quantum state. However, it is often interesting to settle for a coarser way to compare quantum states. This gives rise to different classification schemes. Most entanglement classes are defined based on whether states can be converted to other states using LOCC or a subclass of these operations. The smaller the set of allowed operations, the finer the classification. Important examples are:<br />
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* If two states can be transformed into each other by a local unitary operation, they are said to be in the same ''LU class''. This is the finest of the usually considered classes. Two states in the same LU class have the same value for entanglement measures and the same value as a resource in the distant-labs setting. There is an infinite number of different LU classes (even in the simplest case of two qubits in a pure state).<ref name="GRB1998">>{{cite journal |author1=Grassl, M. |author2=Rötteler, M. |author3=Beth, T. |title=Computing local invariants of quantum-bit systems |journal=Phys. Rev. A |volume=58 |issue=3 |pages=1833–1839 |year=1998 |doi=10.1103/PhysRevA.58.1833 |arxiv=quant-ph/9712040|bibcode=1998PhRvA..58.1833G |s2cid=15892529 }}</ref><ref name="Kraus2010">{{cite journal |author=B. Kraus |authorlink=Barbara Kraus|title=Local unitary equivalence of multipartite pure states |journal=Phys. Rev. Lett. |volume=104 |issue=2 |page=020504 |year=2010 |arxiv=0909.5152 |doi=10.1103/PhysRevLett.104.020504|pmid=20366579 |bibcode=2010PhRvL.104b0504K|s2cid=29984499}}</ref><br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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对于混合态,简化冯纽曼熵并不是唯一合理的纠缠度量。<br />
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* If two states can be transformed into each other by local operations including measurements with probability larger than 0, they are said to be in the same 'SLOCC class' ("stochastic LOCC"). Qualitatively, two states <math>\rho_1</math> and <math>\rho_2</math> in the same SLOCC class are equally powerful (since I can transform one into the other and then do whatever it allows me to do), but since the transformations <math>\rho_1\to\rho_2</math> and <math>\rho_2\to\rho_1</math> may succeed with different probability, they are no longer equally valuable. E.g., for two pure qubits there are only two SLOCC classes: the entangled states (which contains both the (maximally entangled) Bell states and weakly entangled states like <math>|00\rangle+0.01|11\rangle</math>) and the separable ones (i.e., product states like <math>|00\rangle</math>).<ref>{{cite journal |author=M. A. Nielsen |title=Conditions for a Class of Entanglement Transformations |journal=Phys. Rev. Lett. |volume=83 |issue=2 |page=436 |year=1999 |doi=10.1103/PhysRevLett.83.436 |arxiv=quant-ph/9811053|bibcode=1999PhRvL..83..436N |s2cid=17928003 }}</ref><ref name="GoWa2010">{{cite journal |authors=Gour, G. & Wallach, N. R. |title=Classification of Multipartite Entanglement of All Finite Dimensionality |journal=Phys. Rev. Lett. |volume=111 |issue=6 |page=060502 |year=2013 |doi=10.1103/PhysRevLett.111.060502 |pmid=23971544 |arxiv=1304.7259|bibcode=2013PhRvL.111f0502G |s2cid=1570745 }}</ref><br />
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* Instead of considering transformations of single copies of a state (like <math>\rho_1\to\rho_2</math>) one can define classes based on the possibility of multi-copy transformations. E.g., there are examples when <math>\rho_1\to\rho_2</math> is impossible by LOCC, but <math>\rho_1\otimes\rho_1\to\rho_2</math> is possible. A very important (and very coarse) classification is based on the property whether it is possible to transform an arbitrarily large number of copies of a state <math>\rho</math> into at least one pure entangled state. States that have this property are called [[Entanglement distillation|distillable]]. These states are the most useful quantum states since, given enough of them, they can be transformed (with local operations) into any entangled state and hence allow for all possible uses. It came initially as a surprise that not all entangled states are distillable, those that are not are called '[[Bound entanglement|bound entangled]]'.<ref name="HHH97">{{cite journal |author1=Horodecki, M. |author2=Horodecki, P. |author3=Horodecki, R. |title=Mixed-state entanglement and distillation: Is there a ''bound'' entanglement in nature? |journal=Phys. Rev. Lett. |volume=80 |issue=1998 |pages=5239–5242 |year=1998 |arxiv=quant-ph/9801069|doi=10.1103/PhysRevLett.80.5239 |bibcode=1998PhRvL..80.5239H |s2cid=111379972 }}</ref><ref name="horodecki2007" /><br />
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As an aside, the information-theoretic definition is closely related to entropy in the sense of statistical mechanics (comparing the two definitions in the present context, it is customary to set the Boltzmann constant 1}}). For example, by properties of the Borel functional calculus, we see that for any unitary operator ,<br />
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顺便说一句,信息论的定义与统计力学意义上的熵密切相关(比较在当前语境下的两个定义,通常设置波兹曼常数1})。例如,通过 Borel 泛函微积分的性质,我们可以看到,对于任何幺正算符,<br />
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A different entanglement classification is based on what the quantum correlations present in a state allow A and B to do: one distinguishes three subsets of entangled states: (1) the ''[[Quantum nonlocality|non-local]] states'', which produce correlations that cannot be explained by a local hidden variable model and thus violate a Bell inequality, (2) the ''[[Quantum steering|steerable]] states'' that contain sufficient correlations for A to modify ("steer") by local measurements the conditional reduced state of B in such a way, that A can prove to B that the state they possess is indeed entangled, and finally (3) those entangled states that are neither non-local nor steerable. All three sets are non-empty.<ref name="WJD2007">{{cite journal |title=Steering, Entanglement, Nonlocality, and the Einstein-Podolsky-Rosen Paradox |authors=H. M. Wiseman, S. J. Jones, and A. C. Doherty |journal=Phys. Rev. Lett. |volume=98 |issue=14 |page=140402 |year=2007 |doi=10.1103/PhysRevLett.98.140402 |pmid=17501251 |arxiv=quant-ph/0612147|bibcode=2007PhRvL..98n0402W |s2cid=30078867 }}</ref><br />
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<math>S(\rho) = S \left (U \rho U^* \right).</math><br />
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s (rho) = s left (u rho u ^ * right) . </math > <br />
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=== Entropy ===<br />
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Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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事实上,如果没有这个属性,冯纽曼熵就不会有明确的定义。<br />
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In this section, the entropy of a mixed state is discussed as well as how it can be viewed as a measure of quantum entanglement.<br />
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In particular, could be the time evolution operator of the system, i.e.,<br />
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特别是,可以是系统的时间演化算子,即,<br />
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==== Definition ====<br />
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[[File:Von Neumann entropy for bipartite system plot.svg|right|thumb|200px|The plot of von Neumann entropy Vs Eigenvalue for a bipartite 2-level pure state. When the eigenvalue has value .5, von Neumann entropy is at a maximum, corresponding to maximum entanglement.]]<br />
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<math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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[ math ] u (t) = exp left (frac {-i h t }{ hbar } right) ,[ math ]<br />
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In classical [[information theory]] {{mvar|H}}, the [[Shannon entropy]], is associated to a probability distribution,<math>p_1, \cdots, p_n</math>, in the following way:<ref name="SE">{{cite web |url=http://authors.library.caltech.edu/5516/1/CERpra97b.pdf#page=10 |title=Information-theoretic interpretation of quantum error-correcting codes |first1=Nicolas J. |last1=Cerf |first2=Richard |last2=Cleve }}</ref><br />
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where is the Hamiltonian of the system. Here the entropy is unchanged.<br />
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这个系统的哈密顿量在哪里。这里熵不变。<br />
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: <math>H(p_1, \cdots, p_n ) = - \sum_i p_i \log_2 p_i.</math><br />
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The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the arrow of time towards thermodynamic equilibrium is simply the growing spread of quantum entanglement.<br />
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一个过程的可逆性与由此产生的熵变有关,也就是说,一个过程是可逆的,当且仅当它使系统的熵不变。因此,时间之箭向热力学平衡的前进只不过是量子纠缠的蔓延。<br />
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Since a mixed state {{mvar|ρ}} is a probability distribution over an ensemble, this leads naturally to the definition of the [[von Neumann entropy]]:<br />
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This provides a connection between quantum information theory and thermodynamics.<br />
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这提供了量子信息理论和热力学之间的联系。<br />
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: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right).</math><br />
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Rényi entropy also can be used as a measure of entanglement.<br />
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熵也可以用来度量纠缠。<br />
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In general, one uses the [[Borel functional calculus]] to calculate a non-polynomial function such as {{math|log<sub>2</sub>(''ρ'')}}. If the nonnegative operator {{mvar|ρ}} acts on a finite-dimensional Hilbert space and has eigenvalues <math>\lambda_1, \cdots, \lambda_n</math>, {{math|log<sub>2</sub>(''ρ'')}} turns out to be nothing more than the operator with the same eigenvectors, but the eigenvalues <math>\log_2(\lambda_1), \cdots, \log_2(\lambda_n)</math>. The Shannon entropy is then:<br />
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Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, entanglement entropy is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<br />
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量子纠缠度量了量子态(通常被视为双体)中纠缠的数量。如前所述,纠缠熵是纯态的标准量度(但不再是混合态的量度)。对于混合态,文献中有一些纠缠度量<br />
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: <math>S(\rho) = - \hbox{Tr} \left( \rho \log_2 {\rho} \right) = - \sum_i \lambda_i \log_2 \lambda_i</math>.<br />
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Since an event of probability 0 should not contribute to the entropy, and given that<br />
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The Reeh-Schlieder theorem of quantum field theory is sometimes seen as an analogue of quantum entanglement.<br />
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量子场论的 Reeh-Schlieder 定理有时被看作是量子纠缠的类比。<br />
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:<math> \lim_{p \to 0} p \log p = 0,</math><br />
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the convention {{math|0 log(0) {{=}} 0}} is adopted. This extends to the infinite-dimensional case as well: if {{mvar|ρ}} has [[projection-valued measure|spectral resolution]]<br />
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Entanglement has many applications in quantum information theory. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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纠缠态在量子信息理论中有许多应用。在纠缠的帮助下,否则不可能完成的任务就可能实现。<br />
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: <math> \rho = \int \lambda d P_{\lambda},</math><br />
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Among the best-known applications of entanglement are superdense coding and quantum teleportation.<br />
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其中最著名的应用是超稠密编码和量子遥传纠缠。<br />
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assume the same convention when calculating<br />
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Most researchers believe that entanglement is necessary to realize quantum computing (although this is disputed by some).<br />
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大多数研究人员认为量子纠缠对于实现量子计算是必要的(尽管有些人对此有争议)。<br />
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: <math> \rho \log_2 \rho = \int \lambda \log_2 \lambda d P_{\lambda}.</math><br />
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Entanglement is used in some protocols of quantum cryptography. This is because the "shared noise" of entanglement makes for an excellent one-time pad. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.<br />
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纠缠被用于量子密码学的一些协议中。这是因为纠缠的“共享噪音”造就了绝佳的一次性衬垫。此外,由于测量纠缠对的任何一个成员都会破坏它们共享的纠缠,基于纠缠的量子密码学可以让发送方和接收方更容易地检测到拦截器的存在。<br />
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As in [[entropy|statistical mechanics]], the more uncertainty (number of microstates) the system should possess, the larger the entropy. For example, the entropy of any pure state is zero, which is unsurprising since there is no uncertainty about a system in a pure state. The entropy of any of the two subsystems of the entangled state discussed above is {{math|log(2)}} (which can be shown to be the maximum entropy for {{math|2 × 2}} mixed states).<br />
<br />
In interferometry, entanglement is necessary for surpassing the standard quantum limit and achieving the Heisenberg limit.<br />
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在干涉术中,纠缠态对于超越标准量子极限和达到海森堡极限是必要的。<br />
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<br />
==== As a measure of entanglement ====<br />
<br />
Entropy provides one tool that can be used to quantify entanglement, although other entanglement measures exist.<ref name="arxiv.org">{{cite journal|author1=Plenio|title=An introduction to entanglement measures|year=2007|pages=1–51|volume=1|journal=Quant. Inf. Comp. |arxiv=quant-ph/0504163|bibcode=2005quant.ph..4163P|last2=Virmani}}</ref> If the overall system is pure, the entropy of one subsystem can be used to measure its degree of entanglement with the other subsystems.<br />
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There are several canonical entangled states that appear often in theory and experiments.<br />
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在理论和实验中经常会出现几种典型的纠缠态。<br />
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For bipartite pure states, the von Neumann entropy of reduced states is the unique measure of entanglement in the sense that it is the only function on the family of states that satisfies certain axioms required of an entanglement measure.<br />
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For two qubits, the Bell states are<br />
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对于两个量子比特,贝尔态是<br />
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<br />
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It is a classical result that the Shannon entropy achieves its maximum at, and only at, the uniform probability distribution {1/''n'',...,1/''n''}. Therefore, a bipartite pure state {{math|''ρ'' ∈ ''H''<sub>A</sub> ⊗ ''H''<sub>B</sub>}} is said to be a '''maximally entangled state''' if the reduced state{{clarify|reason=To which system, A or B, or perhaps both?|date=May 2015}} of {{mvar|ρ}} is the diagonal matrix<br />
<br />
<math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
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< math > | Phi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 0 rangle _ b | 1 rangle _ a o times | 1 rangle _ b) </math > <br />
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<br />
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<math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
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< math > | Psi ^ pm rangle = frac {1}{ sqrt {2}(| 0 rangle _ a o times | 1 rangle _ b pm | 1 rangle _ a o times | 0 rangle _ b) </math > .<br />
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: <math>\begin{bmatrix} \frac{1}{n}& & \\ & \ddots & \\ & & \frac{1}{n}\end{bmatrix}.</math><br />
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These four pure states are all maximally entangled (according to the entropy of entanglement) and form an orthonormal basis (linear algebra) of the Hilbert space of the two qubits. They play a fundamental role in Bell's theorem.<br />
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这四个纯态都是最大纠缠态(根据纠缠熵) ,并且形成了两个量子位的希尔伯特空间的标准正交基(线性代数)。它们在贝尔定理中起着基本的作用。<br />
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For mixed states, the reduced von Neumann entropy is not the only reasonable entanglement measure.<br />
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<br />
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For M>2 qubits, the GHZ state is<br />
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对于 m > 2量子位,GHZ 态是<br />
<br />
As an aside, the information-theoretic definition is closely related to [[entropy (statistical views)|entropy]] in the sense of statistical mechanics{{Citation needed|date=January 2009}} (comparing the two definitions in the present context, it is customary to set the [[Boltzmann constant]] {{math|''k'' {{=}} 1}}). For example, by properties of the [[Borel functional calculus]], we see that for any [[unitary operator]] {{mvar|U}},<br />
<br />
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<math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
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< math > | mathrm { GHZ } rangle = frac { | 0 rangle ^ { otimes m } + | 1 rangle ^ { otimes m }{ sqrt {2} ,</math > <br />
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: <math>S(\rho) = S \left (U \rho U^* \right).</math><br />
<br />
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which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to qudits, i.e., systems of d rather than 2 dimensions.<br />
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它缩小到贝尔状态。传统的 GHZ 状态定义为 < math > m = 3 </math > 。GHZ 状态偶尔会扩展到 qudit,即 d 而不是2维系统。<br />
<br />
Indeed, without this property, the von Neumann entropy would not be well-defined.<br />
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Also for M>2 qubits, there are spin squeezed states. Spin squeezed states are a class of squeezed coherent states satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled. Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<br />
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对于 m > 2量子位,也存在自旋压缩态。自旋压缩态是一类对自旋测量不确定度满足一定限制的压缩相干态,它必然是纠缠态。自旋压缩态是利用量子纠缠增强精密测量的理想候选态。<br />
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In particular, {{mvar|U}} could be the time evolution operator of the system, i.e.,<br />
<br />
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For two bosonic modes, a NOON state is<br />
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对于两个玻色模态,NOON 状态是<br />
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: <math>U(t) = \exp \left(\frac{-i H t }{\hbar}\right),</math><br />
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<math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
<br />
[数学] | psi _ text { NOON } rangle = frac { | n rangle _ a | 0 rangle _ b + | {0} rangle _ a | { n } rangle _ b }{ sqrt {2} ,,</math > <br />
<br />
where {{mvar|H}} is the [[Hamiltonian (quantum mechanics)|Hamiltonian]] of the system. Here the entropy is unchanged.<br />
<br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the N photons are in one mode" and "the N photons are in the other mode".<br />
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这就像贝尔态 < math > | Psi ^ + rangle </math > 除了基函数0和1已经被“ n 个光子处于一种模式”和“ n 个光子处于另一种模式”所取代。<br />
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The reversibility of a process is associated with the resulting entropy change, i.e., a process is reversible if, and only if, it leaves the entropy of the system invariant. Therefore, the march of the [[arrow of time]] towards [[thermodynamic equilibrium]] is simply the growing spread of quantum entanglement.<ref>{{cite news |url=https://www.wired.com/2014/04/quantum-theory-flow-time/ |title=New Quantum Theory Could Explain the Flow of Time |last1=Wolchover |first1=Natalie |date=25 April 2014 |website=www.wired.com |publisher=Quanta Magazine |accessdate=27 April 2014}}</ref><br />
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This provides a connection between [[quantum information theory]] and [[thermodynamics]].<br />
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Finally, there also exist twin Fock states for bosonic modes, which can be created by feeding a Fock state into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<br />
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最后,还存在玻色子模式的双 Fock 态,它可以通过将 Fock 态输入到两个导致分束器的臂来产生。它们是 NOON 态的倍数之和,可以用来实现海森堡极限。<br />
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[[Rényi entropy]] also can be used as a measure of entanglement.<br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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对于适当选择的纠缠度量,Bell、 GHZ 和 NOON 态是最大纠缠态,而自旋压缩态和双 Fock 态只是部分纠缠。部分纠缠态通常更容易在实验上准备。<br />
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=== Entanglement measures ===<br />
<br />
Entanglement measures quantify the amount of entanglement in a (often viewed as a bipartite) quantum state. As aforementioned, [[entropy of entanglement|entanglement entropy]] is the standard measure of entanglement for pure states (but no longer a measure of entanglement for mixed states). For mixed states, there are some entanglement measures in the literature<ref name="arxiv.org" /> and no single one is standard.<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is spontaneous parametric down-conversion to generate a pair of photons entangled in polarisation. Other methods include the use of a fiber coupler to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a quantum dot, the use of the Hong–Ou–Mandel effect, etc., In the earliest tests of Bell's theorem, the entangled particles were generated using atomic cascades.<br />
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纠缠通常是由亚原子粒子间的直接相互作用产生的。这些相互作用可以有多种形式。最常用的方法之一是用自发参量下转换产生一对纠缠在偏振中的光子。其他方法包括使用光纤耦合器来限制和混合光子,量子点中双激子衰变级联发射的光子,Hong-Ou-Mandel 效应的使用等等。在贝尔定理最早的测试中,纠缠粒子是利用原子级联产生的。<br />
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* Entanglement cost<br />
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* [[entanglement distillation|Distillable entanglement]]<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of entanglement swapping. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<br />
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通过使用纠缠交换,也有可能在不直接相互作用的量子系统之间创造纠缠。如果它们的波函数在空间上仅仅重叠,至少是部分重叠,那么它们也可以相互纠缠全同粒子。<br />
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* Entanglement of formation<br />
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* [[quantum relative entropy|Relative entropy of entanglement]]<br />
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* [[Squashed entanglement]]<br />
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* [[Logarithmic negativity]]<br />
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A density matrix ρ is called separable if it can be written as a convex sum of product states, namely<br />
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密度矩阵 ρ 称为可分的,如果它可以写成乘积态的凸和,即<br />
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Most (but not all) of these entanglement measures reduce for pure states to entanglement entropy, and are difficult ([[NP-hard]]) to compute.<ref>{{cite journal|last1=Huang|first1=Yichen|title=Computing quantum discord is NP-complete|journal=New Journal of Physics|date=21 March 2014|volume=16|issue=3|pages=033027|doi=10.1088/1367-2630/16/3/033027|bibcode=2014NJPh...16c3027H|arxiv = 1305.5941 |s2cid=118556793}}</ref><br />
<br />
<br />
<br />
<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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显示方式{ rho = sum _ j p _ j rho _ j ^ {(a)}次 rho _ j ^ {(b)}} </math > <br />
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=== Quantum field theory ===<br />
<br />
The [[Reeh-Schlieder theorem]] of [[quantum field theory]] is sometimes seen as an analogue of quantum entanglement.<br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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概率为1 ge p _ j ge 0 </math > 。根据定义,如果一个态不可分离,它就是纠缠态。<br />
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== Applications ==<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple Peres–Horodecki criterion provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes NP-hard when generalized. Other separability criteria include (but not limited to) the range criterion, reduction criterion, and those based on uncertainty relations. See Ref. for a review of separability criteria in discrete variable systems.<br />
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对于2量子比特和2 × 2量子比特-量子特里特系统(分别为2 × 2和2 × 3) ,简单的 Peres-horowitz 准则为分离提供了一个必要和充分的判据,从而无意识地提供了检测纠缠的判据。然而,对于一般情形,该判据仅仅是可分性的必要条件,因为问题一经推广就变成了 np 难问题。其他可分性标准包括(但不限于)范围标准、归约标准和基于不确定关系的标准。参见参考文献。回顾了离散变量系统的可分性准则。<br />
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Entanglement has many applications in [[quantum information theory]]. With the aid of entanglement, otherwise impossible tasks may be achieved.<br />
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A numerical approach to the problem is suggested by Jon Magne Leinaas, Jan Myrheim and Eirik Ovrum in their paper "Geometrical aspects of entanglement". Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in Peres-Horodecki criterion testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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Jon Magne Leinaas,Jan Myrheim 和 Eirik Ovrum 在他们的论文“纠缠的几何方面”中提出了一个数值方法来解决这个问题。莱纳斯等。提供一个数值方法,迭代精炼一个估计的可分离状态朝向要测试的目标状态,并检查目标状态是否确实能够到达。该算法的一个实现(包括内置的 peres-horowitz 标准测试)是[ StateSeparator http://phweb.technion.ac.il/~StateSeparator/] web-app。<br />
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Among the best-known applications of entanglement are [[superdense coding]] and [[quantum teleportation]].<ref>{{cite journal |last1=Bouwmeester |first1=Dik |last2=Pan |first2=Jian-Wei|last3=Mattle |first3=Klaus|last4=Eibl |first4=Manfred |last5=Weinfurter |first5=Harald|last6=Zeilinger |first6=Anton|year=1997 |title=Experimental Quantum Teleportation |journal=Nature |volume=390 |issue=6660 |pages=575–579 |name-list-style=amp |url=http://qudev.ethz.ch/content/courses/QSIT06/pdfs/Bouwmeester97.pdf |doi=10.1038/37539|bibcode = 1997Natur.390..575B |arxiv=1901.11004 |s2cid=4422887 }}</ref><br />
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In continuous variable systems, the Peres-Horodecki criterion also applies. Specifically, Simon formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref. for a seemingly different but essentially equivalent approach). It was later found that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators or by using entropic measures.<br />
<br />
在连续变量系统中,Peres-Horodecki 准则也适用。具体地说,Simon 根据正则算符的二阶矩,制定了 Peres-Horodecki 准则的一个特定版本,并表明它对于 < math > 1 oplus1 </math >-mode Gaussian 状态是必要的和充分的。看似不同,但本质上等价的方法)。后来发现,Simon 的条件对于 < math > 1 oplus n </math >-mode Gaussian 状态也是必要和充分的,但是对于 < math > 2 oplus2 </math >-mode Gaussian 状态不再是充分的。Simon 条件可以通过考虑正则算子的高阶矩或者用熵测度来推广。<br />
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Most researchers believe that entanglement is necessary to realize [[quantum computer|quantum computing]] (although this is disputed by some).<ref name="jozsa02">{{cite journal|author1=Richard Jozsa|author2=Noah Linden|doi=10.1098/rspa.2002.1097|title=On the role of entanglement in quantum computational speed-up|year=2002|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=459|issue=2036|pages=2011–2032|arxiv=quant-ph/0201143|bibcode = 2003RSPSA.459.2011J |citeseerx=10.1.1.251.7637|s2cid=15470259}}</ref><br />
<br />
In 2016 China launched the world’s first quantum communications satellite. The $100m Quantum Experiments at Space Scale (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
<br />
2016年,中国发射了世界上第一颗量子通信卫星。耗资1亿美元的空间量子实验任务于2016年8月16日当地时间01:40从中国北方的酒泉卫星发射中心空间站发射升空。<br />
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Entanglement is used in some protocols of [[quantum cryptography]].<ref name="ekert91">{{cite journal |doi=10.1103/PhysRevLett.67.661 |title=Quantum cryptography based on Bell's theorem |year=1991 |last1=Ekert |first1=Artur K. |journal=Physical Review Letters |volume=67 |issue=6 |pages=661–663 |pmid=10044956|bibcode = 1991PhRvL..67..661E |s2cid=27683254 |url=http://pdfs.semanticscholar.org/f8dc/c3047eef8da135bca13b926b1e6cf50e7f3a.pdf }}</ref><ref name="horodecki10">{{cite arXiv |eprint=1006.0468|last1=Yin|first1=Juan|title=Contextuality offers device-independent security|last2=Cao|first2=Yuan|last3=Yong|first3=Hai-Lin|last4=Ren|first4=Ji-Gang|last5=Liang|first5=Hao|last6=Liao|first6=Sheng-Kai|last7=Zhou|first7=Fei|last8=Liu|first8=Chang|last9=Wu|first9=Yu-Ping|last10=Pan|first10=Ge-Sheng|last11=Zhang|first11=Qiang|last12=Peng|first12=Cheng-Zhi|last13=Pan|first13=Jian-Wei|class=quant-ph|year=2010}}</ref> This is because the "shared noise" of entanglement makes for an excellent [[one-time pad]]. Moreover, since measurement of either member of an entangled pair destroys the entanglement they share, entanglement-based quantum cryptography allows the sender and receiver to more easily detect the presence of an interceptor.{{citation needed|date=January 2018}}<br />
<br />
For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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在接下来的两年里,这艘以中国古代哲学家墨子命名的飞船将展示量子化的可行性<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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地球和太空之间的通信,并在前所未有的距离上测试量子纠缠。<br />
<br />
In [[interferometry]], entanglement is necessary for surpassing the [[standard quantum limit]] and achieving the [[Heisenberg limit]].<ref>{{cite journal |last1=Pezze |first1=Luca |last2=Smerzi |first2=Augusto|year=2009 |title=Entanglement, Nonlinear Dynamics, and the Heisenberg Limit |journal=Phys. Rev. Lett. |volume=102 |issue=10 |pages=100401 |name-list-style=amp |doi=10.1103/PhysRevLett.102.100401 |pmid=19392092 |bibcode=2009PhRvL.102j0401P|arxiv = 0711.4840 |s2cid=13095638 }}</ref><br />
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<br />
<br />
In the June 16, 2017, issue of Science, Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<br />
<br />
在2017年6月16日的《科学》杂志上。在严格的爱因斯坦定域条件下,从墨丘利卫星到 Lijian、云南和 Delingha、 Quinhai 的基地的 CHSH 估值为2.37 ± 0.09,证明了双光子对的存在和对 Bell 不等式的违反,从而提高了数量级通过光纤实验的传输效率。<br />
<br />
=== Entangled states ===<br />
<br />
There are several canonical entangled states that appear often in theory and experiments.<br />
<br />
<br />
<br />
For two [[qubits]], the [[Bell state]]s are<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be calculated only by consideration of electron entanglement.<br />
<br />
多电子原子的电子壳层总是由纠缠电子组成。只有考虑到电子纠缠,才能计算出正确的电离能。<br />
<br />
<br />
<br />
: <math>|\Phi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |0\rangle_B \pm |1\rangle_A \otimes |1\rangle_B)</math><br />
<br />
: <math>|\Psi^\pm\rangle = \frac{1}{\sqrt{2}} (|0\rangle_A \otimes |1\rangle_B \pm |1\rangle_A \otimes |0\rangle_B)</math>.<br />
<br />
<br />
<br />
It has been suggested that in the process of photosynthesis, entanglement is involved in the transfer of energy between light-harvesting complexes and photosynthetic reaction centers where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using femtosecond spectroscopy, the coherence of entanglement in the Fenna-Matthews-Olson complex was measured over hundreds of femtoseconds (a relatively long time in this regard) providing support to this theory.<br />
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研究表明,在光合作用过程中,纠缠参与了捕光复合物与光合反应中心之间的能量传递,而光(能)是以化学能的形式获得的。没有这样一个过程,光转化为化学能的有效性就无从解释。利用飞秒光谱技术,我们测量了 Fenna-Matthews-Olson 复合体中纠缠态的相干性,时间长达数百飞秒,为这一理论提供了支持。<br />
<br />
These four pure states are all maximally entangled (according to the [[entropy of entanglement]]) and form an [[orthonormal]] [[basis (linear algebra)]] of the Hilbert space of the two qubits. They play a fundamental role in [[Bell's theorem]].<br />
<br />
However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<br />
<br />
然而,关键的后续研究对这些结果的解释提出了质疑,并将报告的电子量子相干特征赋予了发色团中的核动力学。<br />
<br />
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<br />
For M>2 qubits, the [[Greenberger–Horne–Zeilinger state|GHZ state]] is<br />
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In 2020 researchers reported the quantum entanglement between the motion of a millimetre-sized mechanical oscillator and a disparate distant spin system of a cloud of atoms.<br />
<br />
2020年,研究人员报告了一个毫米大小的机械振荡器的运动和一个原子云的不同距离的自旋系统之间的量子纠缠。<br />
<br />
: <math>|\mathrm{GHZ}\rangle = \frac{|0\rangle^{\otimes M} + |1\rangle^{\otimes M}}{\sqrt{2}},</math><br />
<br />
<br />
<br />
which reduces to the Bell state <math>|\Phi^+\rangle</math> for <math>M=2</math>. The traditional GHZ state was defined for <math>M=3</math>. GHZ states are occasionally extended to [[qudit]]s, i.e., systems of ''d'' rather than 2 dimensions.<br />
<br />
In October 2018, physicists reported producing quantum entanglement using living organisms, particularly between photosynthetic molecules within living bacteria and quantized light.<br />
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2018年10月,物理学家报告说,他们利用活体生物制造量子纠缠,特别是利用活体细菌中的光合分子和量子化的光。<br />
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Also for M>2 qubits, there are [[Spin squeezing|spin squeezed states]].<ref>[http://qwiki.stanford.edu/index.php/Spin_Squeezed_State Database error – Qwiki] {{webarchive|url=https://web.archive.org/web/20120821011018/http://qwiki.stanford.edu/index.php/Spin_Squeezed_State |date=21 August 2012 }}</ref> Spin squeezed states are a class of [[squeezed coherent states]] satisfying certain restrictions on the uncertainty of spin measurements, and are necessarily entangled.<ref>{{cite journal | last1 = Kitagawa | first1 = Masahiro | last2 = Ueda | first2 = Masahito | year = 1993 | title = Squeezed Spin States | journal = Phys. Rev. A | volume = 47 | issue = 6| pages = 5138–5143 | doi=10.1103/physreva.47.5138| pmid = 9909547 |bibcode = 1993PhRvA..47.5138K }}</ref> Spin squeezed states are good candidates for enhancing precision measurements using quantum entanglement.<ref>{{cite journal | last1 = Wineland | first1 = D. J. | last2 = Bollinger | first2 = J. J. | last3 = Itano | first3 = W. M. | last4 = Moore | first4 = F. L. | last5 = Heinzen | first5 = D. J. | year = 1992| title = Spin squeezing and reduced quantum noise in spectroscopy | url = | journal = Phys. Rev. A | volume = 46| issue = 11| pages = R6797–R6800| doi = 10.1103/PhysRevA.46.R6797 | pmid = 9908086 |bibcode = 1992PhRvA..46.6797W }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<br />
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生物体(绿色硫细菌)已被研究作为介质,在非相互作用的光模式之间创造量子纠缠,表明光和细菌模式之间的高度纠缠,甚至在某种程度上纠缠在细菌内部。<br />
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For two [[boson]]ic modes, a [[NOON state]] is<br />
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: <math>|\psi_\text{NOON} \rangle = \frac{|N \rangle_a |0\rangle_b + |{0}\rangle_a |{N}\rangle_b}{\sqrt{2}}, \, </math><br />
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This is like the Bell state <math>|\Psi^+\rangle</math> except the basis kets 0 and 1 have been replaced with "the ''N'' photons are in one mode" and "the ''N'' photons are in the other mode".<br />
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Finally, there also exist [[twin Fock states]] for bosonic modes, which can be created by feeding a [[Fock state]] into two arms leading to a beam splitter. They are the sum of multiple of NOON states, and can used to achieve the Heisenberg limit.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.71.1355|pmid = 10055519|title = Interferometric detection of optical phase shifts at the Heisenberg limit|journal = Physical Review Letters|volume = 71|issue = 9|pages = 1355–1358|year = 1993|last1 = Holland|first1 = M. J|last2 = Burnett|first2 = K|bibcode = 1993PhRvL..71.1355H}}</ref><br />
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For the appropriately chosen measure of entanglement, Bell, GHZ, and NOON states are maximally entangled while spin squeezed and twin Fock states are only partially entangled. The partially entangled states are generally easier to prepare experimentally.<br />
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=== Methods of creating entanglement ===<br />
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Entanglement is usually created by direct interactions between subatomic particles. These interactions can take numerous forms. One of the most commonly used methods is [[spontaneous parametric down-conversion]] to generate a pair of photons entangled in polarisation.<ref name="horodecki2007">{{cite journal |author=Horodecki R, Horodecki P, Horodecki M, Horodecki K |title=Quantum entanglement |journal=Rev. Mod. Phys. |arxiv=quant-ph/0702225 |doi =10.1103/RevModPhys.81.865 |year=2009|pages=865–942 |bibcode=2009RvMP...81..865H |volume=81 |issue=2|last2=Horodecki |last3=Horodecki |last4=Horodecki |s2cid=59577352 }}</ref> Other methods include the use of a [[fiber coupler]] to confine and mix photons, photons emitted from decay cascade of the bi-exciton in a [[quantum dot]],<ref>{{Cite journal|last=Akopian|first=N.|date=2006|title=Entangled Photon Pairs from Semiconductor Quantum Dots|journal=Phys. Rev. Lett.|volume=96|issue=2|pages=130501|arxiv=quant-ph/0509060|bibcode=2006PhRvL..96b0501D|doi=10.1103/PhysRevLett.96.020501|pmid=16486553|s2cid=22040546}}</ref> the use of the [[Hong–Ou–Mandel effect]], etc., In the earliest tests of Bell's theorem, the entangled particles were generated using [[atomic cascade]]s.<br />
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It is also possible to create entanglement between quantum systems that never directly interacted, through the use of [[Quantum teleportation#Entanglement swapping|entanglement swapping]]. Two independently prepared, identical particles may also be entangled if their wave functions merely spatially overlap, at least partially.<ref>Rosario Lo Franco and Giuseppe Compagno, "Indistinguishability of Elementary Systems as a Resource for Quantum Information Processing", Phys. Rev. Lett. 120, 240403, 14 June 2018.</ref><br />
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=== Testing a system for entanglement ===<br />
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A density matrix ρ is called [[Separable state|separable]] if it can be written as a convex sum of product states, namely<br />
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<math>\displaystyle{\rho=\sum_j p_j \rho_j^{(A)}\otimes\rho_j^{(B)}}</math><br />
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with <math>1\ge p_j\ge 0</math> probabilities. By definition, a state is entangled if it is not separable.<br />
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For 2-Qubit and Qubit-Qutrit systems (2&nbsp;×&nbsp;2 and 2&nbsp;×&nbsp;3 respectively) the simple [[Peres–Horodecki criterion]] provides both a necessary and a sufficient criterion for separability, and thus—inadvertently—for detecting entanglement. However, for the general case, the criterion is merely a necessary one for separability, as the problem becomes [[NP-hard]] when generalized.<ref name="NP-hard1">Gurvits, L., Classical deterministic complexity of Edmonds' problem and quantum entanglement, in Proceedings of the 35th ACM Symposium on Theory of Computing, ACM Press, New York, 2003.</ref><ref name="NP-hard2">Sevag Gharibian, Strong NP-Hardness of the [[Quantum Separability Problem]], [[Quantum Information]] and what's known as [[Quantum Computing]], Vol. 10, No. 3&4, pp. 343–360, 2010. {{arXiv|0810.4507}}.</ref> Other separability criteria include (but not limited to) the [[range criterion]], [[reduction criterion]], and those based on uncertainty relations.<ref>{{cite journal |last1=Hofmann |first1=Holger F. |last2=Takeuchi |first2=Shigeki |title=Violation of local uncertainty relations as a signature of entanglement |journal=Physical Review A |date=22 September 2003 |volume=68 |issue=3 |page=032103 |doi=10.1103/PhysRevA.68.032103|arxiv=quant-ph/0212090 |bibcode=2003PhRvA..68c2103H |s2cid=54893300 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |title=Characterizing Entanglement via Uncertainty Relations |journal=Physical Review Letters |date=18 March 2004 |volume=92 |issue=11 |page=117903 |doi=10.1103/PhysRevLett.92.117903|pmid=15089173 |arxiv=quant-ph/0306194 |bibcode=2004PhRvL..92k7903G |s2cid=5696147 }}</ref><ref>{{cite journal |last1=Gühne |first1=Otfried |last2=Lewenstein |first2=Maciej |title=Entropic uncertainty relations and entanglement |journal=Physical Review A |date=24 August 2004 |volume=70 |issue=2 |page=022316 |doi=10.1103/PhysRevA.70.022316|bibcode=2004PhRvA..70b2316G |arxiv=quant-ph/0403219 |s2cid=118952931 }}</ref><ref>{{cite journal |last1=Huang |first1=Yichen |title=Entanglement criteria via concave-function uncertainty relations |journal=Physical Review A |date=29 July 2010 |volume=82 |issue=1 |page=012335 |doi=10.1103/PhysRevA.82.012335|bibcode=2010PhRvA..82a2335H }}</ref> See Ref.<ref>{{cite journal|last1=Gühne|first1=Otfried|last2=Tóth|first2=Géza|title=Entanglement detection|journal=Physics Reports|volume=474|issue=1–6|pages=1–75|doi=10.1016/j.physrep.2009.02.004|arxiv = 0811.2803 |bibcode = 2009PhR...474....1G |year=2009|s2cid=119288569}}</ref> for a review of separability criteria in discrete variable systems.<br />
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A numerical approach to the problem is suggested by [[Jon Magne Leinaas]], [[Jan Myrheim]] and [[Eirik Ovrum]] in their paper "Geometrical aspects of entanglement".<ref name="geom approach">{{cite journal | last1 = Leinaas| first1 = Jon Magne| last2 = Myrheim| first2 = Jan| last3 = Ovrum| first3 = Eirik| year = 2006 | title = Geometrical aspects of entanglement | url = | journal = Physical Review A | volume = 74 | issue = | page = 012313 | doi = 10.1103/PhysRevA.74.012313| arxiv = quant-ph/0605079| s2cid = 119443360}}</ref> Leinaas et al. offer a numerical approach, iteratively refining an estimated separable state towards the target state to be tested, and checking if the target state can indeed be reached. An implementation of the algorithm (including a built-in [[Peres-Horodecki criterion]] testing) is [http://phweb.technion.ac.il/~stateseparator/ "StateSeparator"] web-app.<br />
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In continuous variable systems, the [[Peres-Horodecki criterion]] also applies. Specifically, Simon <ref>{{cite journal|last1=Simon|first1=R.|title=Peres-Horodecki Separability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2726–2729|doi=10.1103/PhysRevLett.84.2726|arxiv = quant-ph/9909044 |bibcode = 2000PhRvL..84.2726S|pmid=11017310|year=2000|s2cid=11664720}}</ref> formulated a particular version of the Peres-Horodecki criterion in terms of the second-order moments of canonical operators and showed that it is necessary and sufficient for <math> 1\oplus1 </math>-mode Gaussian states (see Ref.<ref>{{cite journal|last1=Duan|first1=Lu-Ming|last2=Giedke|first2=G.|last3=Cirac|first3=J. I.|last4=Zoller|first4=P.|title=Inseparability Criterion for Continuous Variable Systems|journal=Physical Review Letters|volume=84|issue=12|pages=2722–2725|doi=10.1103/PhysRevLett.84.2722|pmid=11017309|arxiv = quant-ph/9908056 |bibcode = 2000PhRvL..84.2722D |year=2000|s2cid=9948874}}</ref> for a seemingly different but essentially equivalent approach). It was later found <ref>{{cite journal|last1=Werner|first1=R. F.|last2=Wolf|first2=M. M.|title=Bound Entangled Gaussian States|journal=Physical Review Letters|volume=86|issue=16|pages=3658–3661|doi=10.1103/PhysRevLett.86.3658|pmid=11328047|arxiv = quant-ph/0009118 |bibcode = 2001PhRvL..86.3658W |year=2001|s2cid=20897950}}</ref> that Simon's condition is also necessary and sufficient for <math> 1\oplus n </math>-mode Gaussian states, but no longer sufficient for <math> 2\oplus2 </math>-mode Gaussian states. Simon's condition can be generalized by taking into account the higher order moments of canonical operators <ref>{{cite journal|last1=Shchukin|first1=E.|last2=Vogel|first2=W.|title=Inseparability Criteria for Continuous Bipartite Quantum States|journal=Physical Review Letters|volume=95|issue=23|pages=230502|doi=10.1103/PhysRevLett.95.230502|pmid=16384285|arxiv = quant-ph/0508132 |bibcode = 2005PhRvL..95w0502S |year=2005|s2cid=28595936}}</ref><ref>{{cite journal|last1=Hillery|first1=Mark|last2=Zubairy|first2=M.Suhail|title=Entanglement Conditions for Two-Mode States|journal=Physical Review Letters|volume=96|issue=5|doi=10.1103/PhysRevLett.96.050503|arxiv = quant-ph/0507168 |bibcode = 2006PhRvL..96e0503H|pmid=16486912|page=050503|year=2006|s2cid=43756465}}</ref> or by using entropic measures.<ref>{{cite journal|last1=Walborn|first1=S.|last2=Taketani|first2=B.|last3=Salles|first3=A.|last4=Toscano|first4=F.|last5=de Matos Filho|first5=R.|title=Entropic Entanglement Criteria for Continuous Variables|journal=Physical Review Letters|volume=103|issue=16|doi=10.1103/PhysRevLett.103.160505|arxiv = 0909.0147 |bibcode = 2009PhRvL.103p0505W|pmid=19905682|page=160505|year=2009|s2cid=10523704}}</ref><ref>{{cite journal |last1=Yichen Huang |title=Entanglement Detection: Complexity and Shannon Entropic Criteria |journal=IEEE Transactions on Information Theory |date=October 2013 |volume=59 |issue=10 |pages=6774–6778 |doi=10.1109/TIT.2013.2257936|s2cid=7149863 }}</ref><br />
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In 2016 China launched the world’s first quantum communications satellite.<ref>http://physicsworld.com/cws/article/news/2016/aug/16/china-launches-world-s-first-quantum-science-satellite</ref> The $100m [[Quantum Experiments at Space Scale]] (QUESS) mission was launched on Aug 16, 2016, from the Jiuquan Satellite Launch Center in northern China at 01:40 local time.<br />
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For the next two years, the craft – nicknamed "Micius" after the ancient Chinese philosopher – will demonstrate the feasibility of quantum<br />
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communication between Earth and space, and test quantum entanglement over unprecedented distances.<br />
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In the June 16, 2017, issue of ''Science'', Yin et al. report setting a new quantum entanglement distance record of 1,203&nbsp;km, demonstrating the survival of a two-photon pair and a violation of a Bell inequality, reaching a CHSH valuation of 2.37 ± 0.09, under strict Einstein locality conditions, from the Micius satellite to bases in Lijian, Yunnan and Delingha, Quinhai, increasing the efficiency of transmission over prior fiberoptic experiments by an order of magnitude.<ref>{{cite journal | doi = 10.1126/science.aan3211 | volume=356 | title=Satellite-based entanglement distribution over 1200 kilometers | year=2017 | journal=Science | pages=1140–1144 | last1 = Yin | first1 = Juan | last2 = Cao | first2 = Yuan | last3 = Li | first3 = Yu-Huai | last4 = Liao | first4 = Sheng-Kai | last5 = Zhang | first5 = Liang | last6 = Ren | first6 = Ji-Gang | last7 = Cai | first7 = Wen-Qi | last8 = Liu | first8 = Wei-Yue | last9 = Li | first9 = Bo | last10 = Dai | first10 = Hui | last11 = Li | first11 = Guang-Bing | last12 = Lu | first12 = Qi-Ming | last13 = Gong | first13 = Yun-Hong | last14 = Xu | first14 = Yu | last15 = Li | first15 = Shuang-Lin | last16 = Li | first16 = Feng-Zhi | last17 = Yin | first17 = Ya-Yun | last18 = Jiang | first18 = Zi-Qing | last19 = Li | first19 = Ming | last20 = Jia | first20 = Jian-Jun | last21 = Ren | first21 = Ge | last22 = He | first22 = Dong | last23 = Zhou | first23 = Yi-Lin | last24 = Zhang | first24 = Xiao-Xiang | last25 = Wang | first25 = Na | last26 = Chang | first26 = Xiang | last27 = Zhu | first27 = Zhen-Cai | last28 = Liu | first28 = Nai-Le | last29 = Chen | first29 = Yu-Ao | last30 = Lu | first30 = Chao-Yang | last31 = Shu | first31 = Rong | last32 = Peng | first32 = Cheng-Zhi | last33 = Wang | first33 = Jian-Yu | last34 = Pan | first34 = Jian-Wei | issue=6343 | pmid = 28619937| doi-access = free }}</ref><ref>{{cite web | url=http://www.sciencemag.org/news/2017/06/china-s-quantum-satellite-achieves-spooky-action-record-distance | title=China's quantum satellite achieves 'spooky action' at record distance| date=2017-06-14}}</ref><br />
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== Naturally entangled systems ==<br />
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The electron shells of multi-electron atoms always consist of entangled electrons. The correct ionization energy can be [[Configuration interaction|calculated]] only by consideration of electron entanglement.<ref>Frank Jensen: ''Introduction to Computational Chemistry.'' Wiley, 2007, {{ISBN|978-0-470-01187-4}}.</ref><br />
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== Photosynthesis ==<br />
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It has been suggested that in the process of [[photosynthesis]], entanglement is involved in the transfer of energy between [[light-harvesting complex]]es and [[photosynthetic reaction center]]s where light (energy) is harvested in the form of chemical energy. Without such a process, the efficient conversion of light into chemical energy cannot be explained. Using [[femtosecond spectroscopy]], the coherence of entanglement in the [[Fenna-Matthews-Olson complex]] was measured over hundreds of [[femtosecond]]s (a relatively long time in this regard) providing support to this theory.<ref>Berkeley Lab Press Release: ''[http://newscenter.lbl.gov/feature-stories/2010/05/10/untangling-quantum-entanglement/ Untangling the Quantum Entanglement Behind Photosynthesis: Berkeley scientists shine new light on green plant secrets.]''</ref><ref>Mohan Sarovar, Akihito Ishizaki, Graham R. Fleming, K. Birgitta Whaley: ''Quantum entanglement in photosynthetic light harvesting complexes.'' {{arxiv|0905.3787}}</ref><br />
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However, critical follow-up studies question the interpretation of these results and assign the reported signatures of electronic quantum coherence to nuclear dynamics in the chromophores.<ref>{{cite journal | author = R. Tempelaar | author2 = T. L. C. Jansen | author3 = J. Knoester | title = Vibrational Beatings Conceal Evidence of Electronic Coherence in the FMO Light-Harvesting Complex | journal = J. Phys. Chem. B | volume = 118 | issue = 45 | pages = 12865–12872 | date = 2014 | doi=10.1021/jp510074q| pmid = 25321492 }}</ref><ref>{{cite journal | author = N. Christenson | author2 = H. F. Kauffmann | author3 = T. Pullerits | author4 = T. Mancal | title = Origin of Long-Lived Coherences in Light-Harvesting Complexes| journal = J. Phys. Chem. B | volume = 116 | issue = 25 | pages = 7449–7454 | date = 2012 | doi = 10.1021/jp304649c | pmid = 22642682 | pmc = 3789255 | bibcode = 2012arXiv1201.6325C | arxiv = 1201.6325 }}</ref><ref>{{cite journal | author = A. Kolli | author2 = E. J. O’Reilly | author3= G. D. Scholes | author4= A. Olaya-Castro | title = The fundamental role of quantized vibrations in coherent light harvesting by cryptophyte algae| journal = J. Chem. Phys. | volume = 137 | issue = 17 | pages = 174109 | date = 2012 | doi=10.1063/1.4764100| pmid = 23145719 | bibcode = 2012JChPh.137q4109K | arxiv = 1203.5056 | s2cid = 20156821 }}</ref><ref>{{cite journal | author = V. Butkus | author2 = D. Zigmantas | author3= L. Valkunas | author4= D. Abramavicius | title = Vibrational vs. electronic coherences in 2D spectrum of molecular systems| journal = Chem. Phys. Lett. | volume = 545 | issue = 30 | pages = 40–43 | date = 2012 | doi=10.1016/j.cplett.2012.07.014| arxiv = 1201.2753 | bibcode = 2012CPL...545...40B | s2cid = 96663719 }}</ref><ref>{{cite journal | author = V. Tiwari | author2 = W. K. Peters | author3= D. M. Jonas | title = Electronic resonance with anticorrelated pigment vibrations drives photosynthetic energy transfer outside the adiabatic framework | journal = Proc. Natl. Acad. Sci. USA | volume = 110 | issue = 4 | pages = 1203–1208 | date = 2013 | doi=10.1073/pnas.1211157110| pmid = 23267114 | pmc = 3557059 }}</ref><ref>{{cite journal | author = E. Thyrhaug | author2 = K. Zidek | author3 = J. Dostal | author4 = D. Bina | author5 = D. Zigmantas | title = Exciton Structure and Energy Transfer in the Fenna−Matthews− Olson Complex| journal = J. Phys. Chem. Lett. | volume = 7 | issue = 9 | pages = 1653–1660 | date = 2016 | doi=10.1021/acs.jpclett.6b00534| pmid = 27082631 }}</ref><ref>{{cite journal | author = Y. Fujihashi | author2 = G. R. Fleming | author3= A. Ishizaki | title = Impact of environmentally induced fluctuations on quantum mechanically mixed electronic and vibrational pigment states in photosynthetic energy transfer and 2D electronic spectra| journal = J. Chem. Phys. | volume = 142 | issue = 21 | pages = 212403 | date = 2015 | doi=10.1063/1.4914302| pmid = 26049423 | arxiv = 1505.05281 | bibcode = 2015JChPh.142u2403F | s2cid = 1082742 }}</ref><br />
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== Entanglement of macroscopic objects ==<br />
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In 2020 researchers reported the quantum entanglement between the [[Vibrations of a circular membrane|motion of a millimetre-sized mechanical oscillator]] and a disparate distant [[Spin (physics)|spin]] system of a cloud of atoms.<ref>{{cite news |title=Quantum entanglement realized between distant large objects |url=https://phys.org/news/2020-09-quantum-entanglement-distant-large.html |accessdate=9 October 2020 |work=phys.org |language=en}}</ref><ref>{{cite journal |last1=Thomas |first1=Rodrigo A. |last2=Parniak |first2=Michał |last3=Østfeldt |first3=Christoffer |last4=Møller |first4=Christoffer B. |last5=Bærentsen |first5=Christian |last6=Tsaturyan |first6=Yeghishe |last7=Schliesser |first7=Albert |last8=Appel |first8=Jürgen |last9=Zeuthen |first9=Emil |last10=Polzik |first10=Eugene S. |title=Entanglement between distant macroscopic mechanical and spin systems |journal=Nature Physics |date=21 September 2020 |pages=1–6 |doi=10.1038/s41567-020-1031-5 |url=https://www.nature.com/articles/s41567-020-1031-5 |accessdate=9 October 2020 |language=en |issn=1745-2481}}</ref><br />
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=== Entanglement of elements of living systems ===<br />
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In October 2018, physicists reported producing quantum entanglement using [[living organism]]s, particularly between photosynthetic molecules within living [[bacteria]] and [[Photon|quantized light]].<ref name="JPC-20181010">{{cite journal |last1=Marletto |first1=C. |last2=Coles |first2=D.M. |last3=Farrow |first3=T. |last4=Vedral |first4=V. |title=Entanglement between living bacteria and quantized light witnessed by Rabi splitting |date=10 October 2018 |journal=Journal of Physics: Communications |volume=2 |pages=101001 |number=10 |doi=10.1088/2399-6528/aae224 |bibcode=2018JPhCo...2j1001M |arxiv=1702.08075 |s2cid=119236759 }} [[File:CC-BY icon.svg|50px]] Text and images are available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License].</ref><ref name="SA-20181029">{{cite web |last=O'Callaghan |first=Jonathan |title="Schrödinger's Bacterium" Could Be a Quantum Biology Milestone – A recent experiment may have placed living organisms in a state of quantum entanglement |url=https://www.scientificamerican.com/article/schroedingers-bacterium-could-be-a-quantum-biology-milestone/ |date=29 October 2018 |work=[[Scientific American]] |accessdate=29 October 2018 }}</ref><br />
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Living organisms (green sulphur bacteria) have been studied as mediators to create quantum entanglement between otherwise non-interacting light modes, showing high entanglement between light and bacterial modes, and to some extent, even entanglement within the bacteria.<ref>{{cite journal | last1 = Krisnanda | first1 = T. | last2 = Marletto | first2 = C. | last3 = Vedral | first3 = V. | last4 = Paternostro | first4 = M. | last5 = Paterek | first5 = T. | year = 2018 | title = Probing quantum features of photosynthetic organisms | url = https://www.nature.com/articles/s41534-018-0110-2 | journal = NPJ Quantum Information | volume = 4 | issue = | page = 60 | doi = 10.1038/s41534-018-0110-2 | doi-access = free }}</ref><br />
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== See also ==<br />
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{{Portal|Physics}}<br />
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{{cols|colwidth=21em}}<br />
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* [[Quantum gate#Controlled gates|CNOT gate]]<br />
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* [[Bound entanglement]]<br />
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* [[Concurrence (quantum computing)]]<br />
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* [[Einstein's thought experiments]]<br />
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* [[Entanglement distillation]]<br />
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* [[Entanglement witness]]<br />
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* [[Faster-than-light communication]]<br />
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* [[Ghirardi–Rimini–Weber theory]]<br />
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* [[Multipartite entanglement]]<br />
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* [[Normally distributed and uncorrelated does not imply independent]]<br />
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* [[Observer effect (physics)]]<br />
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* [[Quantum coherence]]<br />
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* [[Quantum discord]]<br />
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* [[Quantum phase transition]]<br />
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* [[Quantum computing]]<br />
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* [[Quantum network]]<br />
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Category:Quantum information science<br />
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类别: 量子信息科学<br />
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* [[Quantum pseudo-telepathy]]<br />
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Category:Quantum mechanics<br />
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类别: 量子力学<br />
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* [[Quantum teleportation]]<br />
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Category:Unsolved problems in physics<br />
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类别: 物理学中未解决的问题<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Quantum entanglement]]. Its edit history can be viewed at [[量子纠缠/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E5%8F%8C%E7%9B%B8%E6%BC%94%E5%8C%96&diff=21019双相演化2021-01-20T07:59:16Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|A process that drives self-organization within complex adaptive systems}}<br />
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'''Dual phase evolution''' ('''DPE''') is a process that drives [[self-organization]] within [[complex adaptive system]]s.<ref name="DPE2"><br />
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Dual phase evolution (DPE) is a process that drives self-organization within complex adaptive systems. It arises in response to phase changes within the network of connections formed by a system's components. DPE occurs in a wide range of physical, biological and social systems. Its applications to technology include methods for manufacturing novel materials and algorithms to solve complex problems in computation.<br />
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<font color="#ff8000">Dual phase evolution 双相演化</font>(DPE)是一个在复杂自适应系统中驱动自组织的过程。它的产生是对系统组成部分所形成的连接网络中的相位变化的响应。DPE发生在广泛的物理、生物和社会系统中。它在技术上的应用包括制造新材料的方法和解决复杂计算问题的算法。<br />
{{cite book<br />
<br />
| author = Green, D.G.<br />
<br />
| author2 = Liu, J. <br />
<br />
| author3-link = Hussein Abbass <br />
<br />
Dual phase evolution (DPE) is a process that promotes the emergence of large-scale order in complex systems. It occurs when a system repeatedly switches between various kinds of phases, and in each phase different processes act on the components or connections in the system. DPE arises because of a property of graphs and networks: the connectivity avalanche that occurs in graphs as the number of edges increases. This avalanche amounts to a sudden phase change in the size of the largest connected subgraph. In effect, a graph has two phases: connected (most nodes are linked by pathways of interaction) and fragmented (nodes are either isolated or form small subgraphs). These are often referred to as global and local phases, respectively.<br />
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双相演化(DPE)是一个促进复杂系统中大规模有序出现的过程。当一个系统在不同的阶段之间反复切换,并且在每个阶段中,不同的过程作用于系统中的组件或连接时,就会发生这种情况。DPE的产生是因为图和网络的一个特性:当边的数目增加时,图中发生连接性雪崩。这种雪崩相当于最大连通子图大小的突然相位变化。实际上,一个图有两个阶段:连接(大多数节点通过相互作用的路径连接)和分段(节点要么是孤立的,要么形成小的子图)。这些阶段通常分别称为全局阶段和局部阶段。 <br />
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| author3 = Abbass, H.<br />
<br />
Fragmented graph.<br />
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零碎的图表。<br />
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| name-list-style = amp<br />
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Connected graph.<br />
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连通图。<br />
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| year = 2014<br />
<br />
| title = Dual Phase Evolution: from Theory to Practice<br />
<br />
An essential feature of DPE is that the system undergoes repeated shifts between the two phases. In many cases, one phase is the system's normal state and it remains in that phase until shocked into the alternate phase by a disturbance, which may be external in origin.<br />
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DPE 的一个基本特征是系统在两个阶段之间进行不断重复的转换。在许多情况下,一个阶段是系统的正常状态,它保持在该阶段,直到受到一种可能来自外部的扰动而进入交替阶段。<br />
<br />
| publisher = Springer<br />
<br />
| location = Berlin<br />
<br />
| isbn = 978-1441984227<br />
<br />
| author2-link = Liu Jing (programmer) <br />
<br />
In each of the two phases, the network is dominated by different processes.<br />
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在双阶段中的任一个阶段,网络都由不同的进程控制。<br />
<br />
| author-link = David G. Green <br />
<br />
}}</ref> It arises in response to phase changes within the network of connections formed by a system's components. DPE occurs in a wide range of physical, biological and social systems. Its applications to technology include methods for manufacturing novel materials and algorithms to solve complex problems in computation.<br />
它的产生是对系统组成部分所形成的连接网络中的相位变化的响应。DPE发生在广泛的物理、生物和社会系统中。它在技术上的应用包括制造新材料的方法和解决复杂计算问题的算法。<br />
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== Introduction介绍 ==<br />
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DPE is capable of producing social networks with known topologies, notably small-world networks and scale-free networks. In the absence of social interaction, the uptake of an opinion promoted by media is a Markov process. The effect of social interaction under DPE is to retard the initial uptake until the number converted reaches a critical point, after which uptake accelerates rapidly.<br />
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DPE能够产生具有已知拓扑结构的社交网络,特别是小世界网络和无标度网络。在缺乏社会互动的情况下,媒体对某一观点的接受是一个<font color="#ff8000"> Markov process马尔可夫过程</font>。DPE下的社会互动效应是延迟最初的吸收,直到转化的数量达到临界点,之后的吸收将迅速加速。 <br />
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Dual phase evolution (DPE) is a process that promotes the emergence of large-scale order in [[complex systems]]. It occurs when a system repeatedly switches between various kinds of phases, and in each phase different processes act on the components or connections in the system. DPE arises because of a property of [[Graph theory|graphs]] and [[Network theory|networks]]: the connectivity avalanche that occurs in graphs as the number of edges increases.<ref name=Erdos1960 /><br />
双相演化(DPE)是一个促进复杂系统中大规模有序出现的过程。当一个系统在不同的阶段之间反复切换,并且在每个阶段中,不同的过程作用于系统中的组件或连接时,就会发生这种情况。DPE的产生是由于[[图论|图]]和[[网络论|网络]]的一个性质:当边的数目增加时,图中的连接性雪崩将会发生<br />
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Social networks provide a familiar example. In a [[social network]] the nodes of the network are people and the network connections (edges) are relationships or interactions between people. For any individual, social activity alternates between a ''local phase'', in which they interact only with people they already know, and a ''global phase'' in which they can interact with a wide pool of people not previously known to them. Historically, these phases have been forced on people by constraints of time and space. People spend most of their time in a local phase and interact only with those immediately around them (family, neighbors, colleagues). However, intermittent activities such as parties, holidays, and conferences involve a shift into a global phase where they can interact with different people they do not know. Different processes dominate each phase. Essentially, people make new social links when in the global phase, and refine or break them (by ceasing contact) while in the local phase.<br />
社交网络提供了一个熟悉的例子。在[[社交网络]]中,网络的节点是人,网络连接(边缘)是人与人之间的关系或互动。对于任何个人来说,社会活动都是在“局部阶段”和“全局阶段”之间交替进行的,前者只与他们已经认识的人进行互动,后者可以与他们以前不认识的大量人进行互动。历史上,这些阶段是由于时间和空间的限制而强加给人们的。人们把大部分时间花在当地阶段,只与周围的人(家人、邻居、同事)交流。然而,诸如聚会、假日和会议之类的间歇式活动涉及到一个全球阶段的转变,在这个阶段,他们可以与不认识的不同的人进行互动。不同的过程控制着每个阶段。从本质上讲,人们在全球阶段建立新的社会联系,在本地阶段则通过停止联系来改善或打破这种联系。 <br />
DPE models of socio-economics interpret the economy as networks of economic agents. Several studies have examined the way socioeconomics evolve when DPE acts on different parts of the network. One model interpreted society as a network of occupations with inhabitants matched to those occupations. In this model social dynamics become a process of DPE within the network, with regular transitions between a development phase, during which the network settles into an equilibrium state, and a mutating phase, during which the network is transformed in random ways by the creation of new occupations.<br />
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社会经济学的DPE模型将经济解释为经济主体网络。有几项研究考察了当DPE作用于网络的不同部分时,社会经济学的发展方式。一个模型将社会解释为一个职业网络,其居民与这些职业相匹配。在这个模型中,社会动态成为网络内的DPE过程,在发展阶段(网络进入平衡状态)和变异阶段(网络通过创造新的职业以随机方式转变)之间有规律的过渡。<br />
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== The DPE mechanism DPE机制==<br />
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Another model interpreted growth and decline in socioeconomic activity as a conflict between cooperators and defectors. The cooperators form networks that lead to prosperity. However, the network is unstable and invasions by defectors intermittently fragment the network, reducing prosperity, until invasions of new cooperators rebuild networks again. Thus prosperity is seen as a dual phase process of alternating highly prosperous, connected phases and unprosperous, fragmented phases.<br />
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另一个模型将社会经济活动的增长和衰退解释为合作者和叛逃者之间的冲突。合作者形成了通向繁荣的网络。然而,网络是不稳定的,叛逃者的入侵断断续续地破坏了网络,降低了繁荣,直到新的合作者再次入侵重建网络。因此,繁荣被视为一个高度繁荣、相互联系的阶段和不繁荣、支离破碎的阶段交替的双相过程。<br />
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The following features are necessary for DPE to occur.<ref name="DPE2" /><br />
发生DPE需要以下特性<br />
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=== Underlying network底层网络 ===<br />
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In a forest, the landscape can be regarded as a network of sites where trees might grow. Some sites are occupied by living trees; others sites are empty. In the local phase, sites free of trees are few and they are surrounded by forest, so the network of free sites is fragmented. In competition for these free sites, local seed sources have a massive advantage, and seeds from distant trees are virtually excluded. Even if a few isolated trees do find free ground, their population is prevented from expanding by established populations, even if the invaders are better adapted to the local environment. A fire in such conditions leads to an explosion of the invading population, and possibly to a sudden change in the character of the entire forest.<br />
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在森林中,景观可以看作是树木生长的场所网络。有些地方被活生生的树木占据,有些地方则是空的。在局部阶段,没有树木的站点很少,而且被森林包围,因此自由站点的网络是碎片化的。在对这些免费站点的竞争中,当地的种子来源具有巨大的优势,而来自遥远树木的种子几乎被排除在外。即使一些孤立的树木确实找到了自由的土地,它们的种群也会被已建立的种群所阻止,即使入侵者能够更好地适应当地的环境。在这种情况下发生的火灾会导致入侵人口的爆炸,并可能导致整个森林性质的突然变化。<br />
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DPE occurs where a system has an underlying network. That is, the system's components form a set of nodes and there are connections (edges) that join them. For example, a family tree is a network in which the nodes are people (with names) and the edges are relationships such as "mother of" or "married to". The nodes in the network can take physical form, such as atoms held together by atomic forces, or they may be dynamic states or conditions, such as positions on a chess board with moves by the players defining the edges.<br />
DPE发生在系统有底层网络的地方。也就是说,系统的组件形成一组节点,并且有连接(边)将它们连接起来。例如,家谱是一个网络,其中节点是人(有名字),边是关系,如“母亲”或“已婚”。网络中的节点可以采取物理形式,例如原子力将原子结合在一起,或者它们可以是动态状态或条件,例如棋盘上的位置,棋手的移动定义了边缘。 <br />
This dual phase process in the landscape explains the consist appearance of pollen zones in the postglacial forest history of North America, Europe, as well as the suppression of widespread taxa, such as beech and hemlock, followed by huge population explosions. Similar patterns, pollen zones truncated by fire-induced boundaries, have been recorded in most parts of the world<br />
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景观中的这种双相过程解释了北美、欧洲冰川后森林历史中花粉带的出现,以及广泛分布的分类群(如山毛榉和铁杉)受到抑制,随后出现巨大的种群爆炸。类似的模式,花粉带被火引起的边界截断,在世界大部分地区都有记录 <br />
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In mathematical terms ([[graph theory]]), a graph <math>\textstyle G = \langle N,E\rangle</math> is a set of nodes <math>\textstyle N</math> and a set of edges <math>\textstyle E \subset \{ (x,y) \mid x,y \in N \}</math>. Each edge <math>\textstyle (x,y )</math> provides a link between a pair of nodes <math>\textstyle x</math> and <math>\textstyle y</math>. A network is a graph in which values are assigned to the nodes and/or edges.<br />
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在数学术语([[图论]])中,图textstyle G=\langle N,E\rangle是一组节点textstyle N和一组边textstyle E\subset\{(x,y)\mid x,y\In N\}。每条边提供一对节点textstyle x和textstyle y之间的链接。网络是一种图形,其中的值分配给节点或边。<br />
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=== Phase shifts相变 ===<br />
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Dual phase evolution is a family of search algorithms that exploit phase changes in the search space to mediate between local and global search. In this way they control the way algorithms explore a search space, so they can be regarded as a family of metaheuristic methods.<br />
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双相演化算法是利用搜索空间中的相位变化,在局部搜索和全局搜索之间进行调节的一类搜索算法。通过这种方式,它们控制算法探索搜索空间的方式,因此它们可以被看作是一族元启发式方法。<br />
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Graphs and networks have two phases: disconnected (fragmented) and connected. In the connected phase every node is connected by an edge to at least one other node and for any pair of nodes, there is at least one path (sequence of edges) joining them.<br />
图和网络有两个阶段:断开(碎片化)和连接。在连接阶段,每个节点通过一条边连接到至少一个其他节点,对于任何一对节点,至少有一条路径(边序列)连接它们<br />
Problems such as optimization can typically be interpreted as finding the tallest peak (optimum) within a search space of possibilities. The task can be approached in two ways: local search (e.g. hill climbing) involves tracing a path from point to point, and always moving "uphill". Global search involves sampling at wide-ranging points in the search space to find high points.<br />
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诸如优化之类的问题通常可以解释为在可能的搜索空间内找到最高的峰值(最优)。这个任务可以通过两种方式来完成:局部搜索(例如爬山)包括从一个点到另一个点追踪一条路径,并且总是“上坡”移动。全局搜索包括在搜索空间中的大范围点进行采样,以找到高点。<br />
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The [[Erdős–Rényi model]] shows that random graphs undergo a connectivity avalanche as the density of edges in a graph increases.<ref name="Erdos1960"><br />
[[Erdős–Rényi模型]]表明,随着图中边密度的增加,随机图会经历连接性雪崩。<br />
Many search algorithms involve a transition between phases of global search and local search. A simple example is the Great Deluge algorithm in which the searcher can move at random across the landscape, but cannot enter low-lying areas that are flooded. At first the searcher can wander freely, but rising water levels eventually confine the search to a local area. Many other nature-inspired algorithms adopt similar approaches. Simulated annealing achieves a transition between phases via its cooling schedule. The cellular genetic algorithm places solutions in a pseudo landscape in which they breed only with local neighbours. Intermittent disasters clear patches, flipping the system into a global phase until gaps are filled again.<br />
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许多搜索算法涉及全局搜索和局部搜索阶段之间的转换。一个简单的例子是大洪水算法,在该算法中,搜索者可以在整个地形上随意移动,但不能进入被洪水淹没的低洼地区。起初,搜索者可以自由漫步,但不断上升的水位最终将搜索限制在局部地区。许多其他受自然启发的算法采用类似的方法。模拟退火通过其冷却制度实现了相变。细胞遗传算法将解决方案放置在一个只与本地邻居繁殖的伪环境中。断断续续的灾难清除了补丁,使系统进入一个全局阶段,直到缺口再次被填补。 <br />
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{{cite journal<br />
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| author = Erdős, P.<br />
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Some variations on the memetic algorithm involve alternating between selection at different levels. These are related to the Baldwin effect, which arises when processes acting on phenotypes (e.g. learning) influence selection at the level of genotypes. In this sense, the Baldwin effect alternates between global search (genotypes) and local search (phenotypes).<br />
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模因算法的一些变化涉及到在不同层次的选择之间的交替。这些都与鲍德温效应有关,当作用于表型(如学习)的过程影响基因型水平上的选择时,鲍德温效应就会产生。在这个意义上,鲍德温效应在全局搜索(基因型)和局部搜索(表型)之间交替。 <br />
| author2 = Rényi, A.<br />
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| name-list-style = amp<br />
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| year = 1960<br />
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| title = On the evolution of random graphs<br />
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Dual phase evolution is related to the well-known phenomenon of self-organized criticality (SOC). Both concern processes in which critical phase changes promote adaptation and organization within a system. However, SOC differs from DPE in several fundamental ways. Under SOC, a system's natural condition is to be in a critical state; in DPE a system's natural condition is a non-critical state. In SOC the size of disturbances follows a power law; in DPE disturbances are not necessarily distributed the same way. In SOC a system is not necessarily subject to other processes; in DPE different processes (e.g. selection and variation) operate in the two phases.<br />
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双相演化与自组织临界现象有关。两者都涉及关键阶段变化促进系统内适应和组织的过程。然而,SOC与DPE在几个基本方面不同。在SOC下,系统的自然状态是处于临界状态;在DPE中,系统的自然状态是非临界状态。在SOC中,扰动的大小遵循幂律;在DPE中,扰动的分布不一定相同。在SOC中,一个系统不一定要经历其他过程;在DPE中,不同的过程(如选择和变化)在两个阶段中运行。<br />
| journal = Publications of the Mathematical Institute of the Hungarian Academy of Sciences<br />
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| volume =5<br />
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| pages = 17&ndash;61<br />
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| url = http://www.renyi.hu/~p_erdos/1960-10.pdf<br />
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| author2-link = Alfréd Rényi<br />
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Category:Nature-inspired metaheuristics<br />
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类别: 自然启发的启发式元推理<br />
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<small>This page was moved from [[wikipedia:en:Dual-phase evolution]]. Its edit history can be viewed at [[双相演化/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E5%8F%8C%E7%9B%B8%E6%BC%94%E5%8C%96&diff=21018双相演化2021-01-20T07:56:52Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|A process that drives self-organization within complex adaptive systems}}<br />
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'''Dual phase evolution''' ('''DPE''') is a process that drives [[self-organization]] within [[complex adaptive system]]s.<ref name="DPE2"><br />
<br />
Dual phase evolution (DPE) is a process that drives self-organization within complex adaptive systems. It arises in response to phase changes within the network of connections formed by a system's components. DPE occurs in a wide range of physical, biological and social systems. Its applications to technology include methods for manufacturing novel materials and algorithms to solve complex problems in computation.<br />
<br />
双相演化(DPE)是一个在复杂自适应系统中驱动自组织的过程。它的产生是对系统组成部分所形成的连接网络中的相位变化的响应。DPE发生在广泛的物理、生物和社会系统中。它在技术上的应用包括制造新材料的方法和解决复杂计算问题的算法。<br />
{{cite book<br />
<br />
| author = Green, D.G.<br />
<br />
| author2 = Liu, J. <br />
<br />
| author3-link = Hussein Abbass <br />
<br />
Dual phase evolution (DPE) is a process that promotes the emergence of large-scale order in complex systems. It occurs when a system repeatedly switches between various kinds of phases, and in each phase different processes act on the components or connections in the system. DPE arises because of a property of graphs and networks: the connectivity avalanche that occurs in graphs as the number of edges increases. This avalanche amounts to a sudden phase change in the size of the largest connected subgraph. In effect, a graph has two phases: connected (most nodes are linked by pathways of interaction) and fragmented (nodes are either isolated or form small subgraphs). These are often referred to as global and local phases, respectively.<br />
<br />
双相演化(DPE)是一个促进复杂系统中大规模有序出现的过程。当一个系统在不同的阶段之间反复切换,并且在每个阶段中,不同的过程作用于系统中的组件或连接时,就会发生这种情况。DPE的产生是因为图和网络的一个特性:当边的数目增加时,图中发生连接性雪崩。这种雪崩相当于最大连通子图大小的突然相位变化。实际上,一个图有两个阶段:连接(大多数节点通过相互作用的路径连接)和分段(节点要么是孤立的,要么形成小的子图)。这些阶段通常分别称为全局阶段和局部阶段。 <br />
<br />
| author3 = Abbass, H.<br />
<br />
Fragmented graph.<br />
<br />
零碎的图表。<br />
<br />
| name-list-style = amp<br />
<br />
Connected graph.<br />
<br />
连通图。<br />
<br />
| year = 2014<br />
<br />
| title = Dual Phase Evolution: from Theory to Practice<br />
<br />
An essential feature of DPE is that the system undergoes repeated shifts between the two phases. In many cases, one phase is the system's normal state and it remains in that phase until shocked into the alternate phase by a disturbance, which may be external in origin.<br />
<br />
DPE 的一个基本特征是系统在两个阶段之间进行不断重复的转换。在许多情况下,一个阶段是系统的正常状态,它保持在该阶段,直到受到一种可能来自外部的扰动而进入交替阶段。<br />
<br />
| publisher = Springer<br />
<br />
| location = Berlin<br />
<br />
| isbn = 978-1441984227<br />
<br />
| author2-link = Liu Jing (programmer) <br />
<br />
In each of the two phases, the network is dominated by different processes.<br />
<br />
在双阶段中的任一个阶段,网络都由不同的进程控制。<br />
<br />
| author-link = David G. Green <br />
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}}</ref> It arises in response to phase changes within the network of connections formed by a system's components. DPE occurs in a wide range of physical, biological and social systems. Its applications to technology include methods for manufacturing novel materials and algorithms to solve complex problems in computation.<br />
它的产生是对系统组成部分所形成的连接网络中的相位变化的响应。DPE发生在广泛的物理、生物和社会系统中。它在技术上的应用包括制造新材料的方法和解决复杂计算问题的算法。<br />
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== Introduction介绍 ==<br />
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DPE is capable of producing social networks with known topologies, notably small-world networks and scale-free networks. In the absence of social interaction, the uptake of an opinion promoted by media is a Markov process. The effect of social interaction under DPE is to retard the initial uptake until the number converted reaches a critical point, after which uptake accelerates rapidly.<br />
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DPE能够产生具有已知拓扑结构的社交网络,特别是小世界网络和无标度网络。在缺乏社会互动的情况下,媒体对某一观点的接受是一个马尔可夫过程。DPE下的社会互动效应是延迟最初的吸收,直到转化的数量达到临界点,之后的吸收将迅速加速。 <br />
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Dual phase evolution (DPE) is a process that promotes the emergence of large-scale order in [[complex systems]]. It occurs when a system repeatedly switches between various kinds of phases, and in each phase different processes act on the components or connections in the system. DPE arises because of a property of [[Graph theory|graphs]] and [[Network theory|networks]]: the connectivity avalanche that occurs in graphs as the number of edges increases.<ref name=Erdos1960 /><br />
双相演化(DPE)是一个促进复杂系统中大规模有序出现的过程。当一个系统在不同的阶段之间反复切换,并且在每个阶段中,不同的过程作用于系统中的组件或连接时,就会发生这种情况。DPE的产生是由于[[图论|图]]和[[网络论|网络]]的一个性质:当边的数目增加时,图中的连接性雪崩将会发生<br />
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Social networks provide a familiar example. In a [[social network]] the nodes of the network are people and the network connections (edges) are relationships or interactions between people. For any individual, social activity alternates between a ''local phase'', in which they interact only with people they already know, and a ''global phase'' in which they can interact with a wide pool of people not previously known to them. Historically, these phases have been forced on people by constraints of time and space. People spend most of their time in a local phase and interact only with those immediately around them (family, neighbors, colleagues). However, intermittent activities such as parties, holidays, and conferences involve a shift into a global phase where they can interact with different people they do not know. Different processes dominate each phase. Essentially, people make new social links when in the global phase, and refine or break them (by ceasing contact) while in the local phase.<br />
社交网络提供了一个熟悉的例子。在[[社交网络]]中,网络的节点是人,网络连接(边缘)是人与人之间的关系或互动。对于任何个人来说,社会活动都是在“局部阶段”和“全局阶段”之间交替进行的,前者只与他们已经认识的人进行互动,后者可以与他们以前不认识的大量人进行互动。历史上,这些阶段是由于时间和空间的限制而强加给人们的。人们把大部分时间花在当地阶段,只与周围的人(家人、邻居、同事)交流。然而,诸如聚会、假日和会议之类的间歇式活动涉及到一个全球阶段的转变,在这个阶段,他们可以与不认识的不同的人进行互动。不同的过程控制着每个阶段。从本质上讲,人们在全球阶段建立新的社会联系,在本地阶段则通过停止联系来改善或打破这种联系。 <br />
DPE models of socio-economics interpret the economy as networks of economic agents. Several studies have examined the way socioeconomics evolve when DPE acts on different parts of the network. One model interpreted society as a network of occupations with inhabitants matched to those occupations. In this model social dynamics become a process of DPE within the network, with regular transitions between a development phase, during which the network settles into an equilibrium state, and a mutating phase, during which the network is transformed in random ways by the creation of new occupations.<br />
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社会经济学的DPE模型将经济解释为经济主体网络。有几项研究考察了当DPE作用于网络的不同部分时,社会经济学的发展方式。一个模型将社会解释为一个职业网络,其居民与这些职业相匹配。在这个模型中,社会动态成为网络内的DPE过程,在发展阶段(网络进入平衡状态)和变异阶段(网络通过创造新的职业以随机方式转变)之间有规律的过渡。<br />
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== The DPE mechanism DPE机制==<br />
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Another model interpreted growth and decline in socioeconomic activity as a conflict between cooperators and defectors. The cooperators form networks that lead to prosperity. However, the network is unstable and invasions by defectors intermittently fragment the network, reducing prosperity, until invasions of new cooperators rebuild networks again. Thus prosperity is seen as a dual phase process of alternating highly prosperous, connected phases and unprosperous, fragmented phases.<br />
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另一个模型将社会经济活动的增长和衰退解释为合作者和叛逃者之间的冲突。合作者形成了通向繁荣的网络。然而,网络是不稳定的,叛逃者的入侵断断续续地破坏了网络,降低了繁荣,直到新的合作者再次入侵重建网络。因此,繁荣被视为一个高度繁荣、相互联系的阶段和不繁荣、支离破碎的阶段交替的双相过程。<br />
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The following features are necessary for DPE to occur.<ref name="DPE2" /><br />
发生DPE需要以下特性<br />
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=== Underlying network底层网络 ===<br />
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In a forest, the landscape can be regarded as a network of sites where trees might grow. Some sites are occupied by living trees; others sites are empty. In the local phase, sites free of trees are few and they are surrounded by forest, so the network of free sites is fragmented. In competition for these free sites, local seed sources have a massive advantage, and seeds from distant trees are virtually excluded. Even if a few isolated trees do find free ground, their population is prevented from expanding by established populations, even if the invaders are better adapted to the local environment. A fire in such conditions leads to an explosion of the invading population, and possibly to a sudden change in the character of the entire forest.<br />
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在森林中,景观可以看作是树木生长的场所网络。有些地方被活生生的树木占据,有些地方则是空的。在局部阶段,没有树木的站点很少,而且被森林包围,因此自由站点的网络是碎片化的。在对这些免费站点的竞争中,当地的种子来源具有巨大的优势,而来自遥远树木的种子几乎被排除在外。即使一些孤立的树木确实找到了自由的土地,它们的种群也会被已建立的种群所阻止,即使入侵者能够更好地适应当地的环境。在这种情况下发生的火灾会导致入侵人口的爆炸,并可能导致整个森林性质的突然变化。<br />
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DPE occurs where a system has an underlying network. That is, the system's components form a set of nodes and there are connections (edges) that join them. For example, a family tree is a network in which the nodes are people (with names) and the edges are relationships such as "mother of" or "married to". The nodes in the network can take physical form, such as atoms held together by atomic forces, or they may be dynamic states or conditions, such as positions on a chess board with moves by the players defining the edges.<br />
DPE发生在系统有底层网络的地方。也就是说,系统的组件形成一组节点,并且有连接(边)将它们连接起来。例如,家谱是一个网络,其中节点是人(有名字),边是关系,如“母亲”或“已婚”。网络中的节点可以采取物理形式,例如原子力将原子结合在一起,或者它们可以是动态状态或条件,例如棋盘上的位置,棋手的移动定义了边缘。 <br />
This dual phase process in the landscape explains the consist appearance of pollen zones in the postglacial forest history of North America, Europe, as well as the suppression of widespread taxa, such as beech and hemlock, followed by huge population explosions. Similar patterns, pollen zones truncated by fire-induced boundaries, have been recorded in most parts of the world<br />
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景观中的这种双相过程解释了北美、欧洲冰川后森林历史中花粉带的出现,以及广泛分布的分类群(如山毛榉和铁杉)受到抑制,随后出现巨大的种群爆炸。类似的模式,花粉带被火引起的边界截断,在世界大部分地区都有记录 <br />
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In mathematical terms ([[graph theory]]), a graph <math>\textstyle G = \langle N,E\rangle</math> is a set of nodes <math>\textstyle N</math> and a set of edges <math>\textstyle E \subset \{ (x,y) \mid x,y \in N \}</math>. Each edge <math>\textstyle (x,y )</math> provides a link between a pair of nodes <math>\textstyle x</math> and <math>\textstyle y</math>. A network is a graph in which values are assigned to the nodes and/or edges.<br />
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在数学术语([[图论]])中,图textstyle G=\langle N,E\rangle是一组节点textstyle N和一组边textstyle E\subset\{(x,y)\mid x,y\In N\}。每条边提供一对节点textstyle x和textstyle y之间的链接。网络是一种图形,其中的值分配给节点或边。<br />
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=== Phase shifts相变 ===<br />
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Dual phase evolution is a family of search algorithms that exploit phase changes in the search space to mediate between local and global search. In this way they control the way algorithms explore a search space, so they can be regarded as a family of metaheuristic methods.<br />
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双相演化算法是利用搜索空间中的相位变化,在局部搜索和全局搜索之间进行调节的一类搜索算法。通过这种方式,它们控制算法探索搜索空间的方式,因此它们可以被看作是一族元启发式方法。<br />
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Graphs and networks have two phases: disconnected (fragmented) and connected. In the connected phase every node is connected by an edge to at least one other node and for any pair of nodes, there is at least one path (sequence of edges) joining them.<br />
图和网络有两个阶段:断开(碎片化)和连接。在连接阶段,每个节点通过一条边连接到至少一个其他节点,对于任何一对节点,至少有一条路径(边序列)连接它们<br />
Problems such as optimization can typically be interpreted as finding the tallest peak (optimum) within a search space of possibilities. The task can be approached in two ways: local search (e.g. hill climbing) involves tracing a path from point to point, and always moving "uphill". Global search involves sampling at wide-ranging points in the search space to find high points.<br />
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诸如优化之类的问题通常可以解释为在可能的搜索空间内找到最高的峰值(最优)。这个任务可以通过两种方式来完成:局部搜索(例如爬山)包括从一个点到另一个点追踪一条路径,并且总是“上坡”移动。全局搜索包括在搜索空间中的大范围点进行采样,以找到高点。<br />
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The [[Erdős–Rényi model]] shows that random graphs undergo a connectivity avalanche as the density of edges in a graph increases.<ref name="Erdos1960"><br />
[[Erdős–Rényi模型]]表明,随着图中边密度的增加,随机图会经历连接性雪崩。<br />
Many search algorithms involve a transition between phases of global search and local search. A simple example is the Great Deluge algorithm in which the searcher can move at random across the landscape, but cannot enter low-lying areas that are flooded. At first the searcher can wander freely, but rising water levels eventually confine the search to a local area. Many other nature-inspired algorithms adopt similar approaches. Simulated annealing achieves a transition between phases via its cooling schedule. The cellular genetic algorithm places solutions in a pseudo landscape in which they breed only with local neighbours. Intermittent disasters clear patches, flipping the system into a global phase until gaps are filled again.<br />
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许多搜索算法涉及全局搜索和局部搜索阶段之间的转换。一个简单的例子是大洪水算法,在该算法中,搜索者可以在整个地形上随意移动,但不能进入被洪水淹没的低洼地区。起初,搜索者可以自由漫步,但不断上升的水位最终将搜索限制在局部地区。许多其他受自然启发的算法采用类似的方法。模拟退火通过其冷却制度实现了相变。细胞遗传算法将解决方案放置在一个只与本地邻居繁殖的伪环境中。断断续续的灾难清除了补丁,使系统进入一个全局阶段,直到缺口再次被填补。 <br />
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{{cite journal<br />
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| author = Erdős, P.<br />
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Some variations on the memetic algorithm involve alternating between selection at different levels. These are related to the Baldwin effect, which arises when processes acting on phenotypes (e.g. learning) influence selection at the level of genotypes. In this sense, the Baldwin effect alternates between global search (genotypes) and local search (phenotypes).<br />
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模因算法的一些变化涉及到在不同层次的选择之间的交替。这些都与鲍德温效应有关,当作用于表型(如学习)的过程影响基因型水平上的选择时,鲍德温效应就会产生。在这个意义上,鲍德温效应在全局搜索(基因型)和局部搜索(表型)之间交替。 <br />
| author2 = Rényi, A.<br />
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| name-list-style = amp<br />
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| year = 1960<br />
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| title = On the evolution of random graphs<br />
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Dual phase evolution is related to the well-known phenomenon of self-organized criticality (SOC). Both concern processes in which critical phase changes promote adaptation and organization within a system. However, SOC differs from DPE in several fundamental ways. Under SOC, a system's natural condition is to be in a critical state; in DPE a system's natural condition is a non-critical state. In SOC the size of disturbances follows a power law; in DPE disturbances are not necessarily distributed the same way. In SOC a system is not necessarily subject to other processes; in DPE different processes (e.g. selection and variation) operate in the two phases.<br />
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双相演化与自组织临界现象有关。两者都涉及关键阶段变化促进系统内适应和组织的过程。然而,SOC与DPE在几个基本方面不同。在SOC下,系统的自然状态是处于临界状态;在DPE中,系统的自然状态是非临界状态。在SOC中,扰动的大小遵循幂律;在DPE中,扰动的分布不一定相同。在SOC中,一个系统不一定要经历其他过程;在DPE中,不同的过程(如选择和变化)在两个阶段中运行。<br />
| journal = Publications of the Mathematical Institute of the Hungarian Academy of Sciences<br />
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| volume =5<br />
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| pages = 17&ndash;61<br />
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| url = http://www.renyi.hu/~p_erdos/1960-10.pdf<br />
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| author2-link = Alfréd Rényi<br />
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Category:Nature-inspired metaheuristics<br />
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类别: 自然启发的启发式元推理<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Dual-phase evolution]]. Its edit history can be viewed at [[双相演化/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%BA%92%E6%83%A0%E6%80%A7&diff=21006互惠性2021-01-20T03:40:58Z<p>Henry:</p>
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<div>此词条暂由Henry翻译<br />
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{{Network Science}}<br />
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In [[network science]], '''reciprocity''' is a measure of the likelihood of [[vertex (graph theory)|vertices]] in a [[directed graph|directed network]] to be mutually linked.<ref name="gl04">{{cite journal|title=Patterns of Link Reciprocity in Directed Networks|author=[[Diego Garlaschelli]]|author2=Loffredo, Maria I.|journal=Physical Review Letters|volume=93|issue=26|date=December 2004|page=268701|publisher=[[American Physical Society]]|doi=10.1103/PhysRevLett.93.268701|pmid=15698035|arxiv=cond-mat/0404521|s2cid=1043766}}</ref> Like the [[clustering coefficient]], [[scale-free network|scale-free]] [[degree distribution]], or [[community structure]], reciprocity is a quantitative measure used to study [[complex network]]s.<br />
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In network science, reciprocity is a measure of the likelihood of vertices in a directed network to be mutually linked. Like the clustering coefficient, scale-free degree distribution, or community structure, reciprocity is a quantitative measure used to study complex networks.<br />
在网络科学中,<font color="#ff8000"> Reciprocity互惠性</font>是一种度量有向网络中顶点相互连接的可能性的方法。就像集聚系数、无标度分布或者社区结构一样,互惠性是一种用于研究复杂网络的定量度量。<br />
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==Motivation动机==<br />
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In real network problems, people are interested in determining the [[likelihood]] of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
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In real network problems, people are interested in determining the likelihood of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
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在实际的网络问题中,人们感兴趣的是确定顶点对之间发生双链接(方向相反)的可能性。这个问题对许多人来说都是根本问题<br />
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reasons. First, in the networks that transport information or material (such as email networks,<ref name=reciporcity2>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref> World Wide Web (WWW),<ref name=reciporcity3>{{cite journal | last1=Albert | first1=Réka | last2=Jeong | first2=Hawoong | last3=Barabási | first3=Albert-László | title=Diameter of the World-Wide Web | journal=Nature | volume=401 | issue=6749 | year=1999 | issn=0028-0836 | doi=10.1038/43601 | pages=130–131| arxiv=cond-mat/9907038 | s2cid=4419938 }}</ref> World Trade Web,<ref name=reciporcity4>{{cite journal | last1=Garlaschelli | first1=Diego | last2=Loffredo | first2=Maria I. | title=Fitness-Dependent Topological Properties of the World Trade Web | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=93 | issue=18 | date=2004-10-28 | issn=0031-9007 | doi=10.1103/physrevlett.93.188701 | page=188701| pmid=15525215 | arxiv=cond-mat/0403051 | s2cid=16367275 }}</ref> or Wikipedia<ref name=reciporcity6>{{cite journal | last1=Zlatić | first1=V. | last2=Božičević | first2=M. | last3=Štefančić | first3=H. | last4=Domazet | first4=M. | title=Wikipedias: Collaborative web-based encyclopedias as complex networks | journal=Physical Review E | volume=74 | issue=1 | date=2006-07-24 | issn=1539-3755 | doi=10.1103/physreve.74.016115 | page=016115| pmid=16907159 | arxiv=physics/0602149 | s2cid=3388193 }}</ref> ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the [[clustering coefficient]]). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<ref name="gl04"/><br />
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reasons. First, in the networks that transport information or material (such as email networks, World Wide Web (WWW), World Trade Web, or Wikipedia ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the clustering coefficient). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<br />
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原因。首先,在传输信息或材料的网络(如电子邮件网络、万维网(WWW)、世界贸易网或维基百科)中,相互联系促进了传输过程。其次,在分析有向网络时,为了简单起见,人们通常将其视为无向网络;因此,从互惠性研究中获得的信息有助于估计将有向网络视为无向网络时引入的误差(例如,在测量聚类系数时)。最后,检测非凡的互惠模式可以揭示形成观察到的网络拓扑的可能机制和组织原则。<br />
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<math>r = \frac {L^{<->}}{L}</math><br />
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[ math > r = frac { l ^ { <-> }{ l } </math > <br />
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==How is it defined?它是如何定义的?==<br />
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===Traditional definition传统定义===<br />
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With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
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根据这个定义,r = 1是一个纯粹的双向网络,而<br />
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A traditional way to define the reciprocity r is using the ratio of the number of links pointing in both directions <math>L^{<->}</math> to the total number of links L <ref name=reciporcity5>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref><br />
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<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
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对于一个单向的人来说。实际网络的中间值介于0和1之间。<br />
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<math>r = \frac {L^{<->}}{L}</math><br />
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However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
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然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
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With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
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<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
根据这个定义,r=1表示纯双向网络,r=0表示纯单向的。实际网络的中间值介于0和1之间。<br />
<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
为了克服上述定义的缺陷,加拉舍利和洛弗雷多将互惠性定义为有向图的邻接矩阵项之间的相关系数a{ij}=1如果存在从i到j的链接,如果不存在,a{ij}=0:<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
(a { ji }-bar { a }){ sum { i neq }(a { ij }-bar { a })}(sum { i neq }(a { ij }-bar { a }) ^/math > ,<br />
<br />
===Garlaschelli and Loffredo's definition 加拉舍利和洛弗雷多的定义===<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
为了克服上述定义的缺陷,加拉舍利和洛弗雷多将互惠性定义为有向图的邻接矩阵项之间的相关系数a{ij}。如果存在从i到j的链接,a{ij}=1,如果不存在,a{ij}=0:其中平均值a¯≡∑i≠jaijN(N−1)=LN(N−1)。 <br />
<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
bar{a}测量观察到的与可能的有向链路的比率(链路密度) ,自链路现在被排除在l之外,因为 i 不等于 j。<br />
<br />
<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
The definition can be written in the following simple form:<br />
<br />
定义可以用以下简单的形式写出:<br />
<br />
<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a }} </math > <br />
<br />
<br />
<br />
The definition can be written in the following simple form:<br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络ρ>0和反互惠网络ρ<0,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
如果所有的链接都是相互的,那么如果r=0, ρ=ρmin. 。<br />
<br />
<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a } </math > <br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络ρ>0和反互惠网络ρ<0,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
这是使用ρ的另一个优点,因为它包含了这样一个思想,即在密度较大的网络中,完全反精确更具统计意义,而在稀疏网络中,它则被视为不太明显的效果。<br />
<br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<br />
<br />
在一些真实的社会网络中,Gallos 对这种互惠关系进行了分析。<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
这是使用ρ的另一个优点,因为它包含了这样一个思想,即在密度较大的网络中,完全反精确更具统计意义,而在稀疏网络中,它则被视为不太明显的效果。<br />
<br />
===Reciprocity in real social networks真实社会网络中的互惠性===<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<ref name="GallosRybski2012">{{cite journal|author=Gallos, Lazaros K.|author2=Rybski, Diego|author3=[[Fredrik Liljeros]]|author4=[[Shlomo Havlin]]|author5=Makse, Hernán A.|title=How People Interact in Evolving Online Affiliation Networks|journal=Physical Review X|volume=2|issue=3|year=2012|page=031014|issn=2160-3308|oclc=969762960|doi=10.1103/PhysRevX.2.031014|arxiv=1111.5534|s2cid=16905579}}</ref><br />
<br />
加洛斯分析了现实社会网络中的互惠性。<br />
<br />
Category:Computer networking<br />
<br />
类别: 计算机网络<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Reciprocity (network science)]]. Its edit history can be viewed at [[互惠性/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%BA%92%E6%83%A0%E6%80%A7&diff=21005互惠性2021-01-20T03:40:14Z<p>Henry:/* Reciprocity in real social networks真实社会网络中的互惠性 */</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Network Science}}<br />
<br />
In [[network science]], '''reciprocity''' is a measure of the likelihood of [[vertex (graph theory)|vertices]] in a [[directed graph|directed network]] to be mutually linked.<ref name="gl04">{{cite journal|title=Patterns of Link Reciprocity in Directed Networks|author=[[Diego Garlaschelli]]|author2=Loffredo, Maria I.|journal=Physical Review Letters|volume=93|issue=26|date=December 2004|page=268701|publisher=[[American Physical Society]]|doi=10.1103/PhysRevLett.93.268701|pmid=15698035|arxiv=cond-mat/0404521|s2cid=1043766}}</ref> Like the [[clustering coefficient]], [[scale-free network|scale-free]] [[degree distribution]], or [[community structure]], reciprocity is a quantitative measure used to study [[complex network]]s.<br />
<br />
In network science, reciprocity is a measure of the likelihood of vertices in a directed network to be mutually linked. Like the clustering coefficient, scale-free degree distribution, or community structure, reciprocity is a quantitative measure used to study complex networks.<br />
<br />
在网络科学中,互惠性是一种度量有向网络中顶点相互连接的可能性的方法。就像集聚系数、无标度分布或者社区结构一样,互惠性是一种用于研究复杂网络的定量度量。<br />
<br />
<br />
<br />
==Motivation动机==<br />
<br />
In real network problems, people are interested in determining the [[likelihood]] of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
In real network problems, people are interested in determining the likelihood of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
在实际的网络问题中,人们感兴趣的是确定顶点对之间发生双链接(方向相反)的可能性。这个问题对许多人来说都是根本问题<br />
<br />
reasons. First, in the networks that transport information or material (such as email networks,<ref name=reciporcity2>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref> World Wide Web (WWW),<ref name=reciporcity3>{{cite journal | last1=Albert | first1=Réka | last2=Jeong | first2=Hawoong | last3=Barabási | first3=Albert-László | title=Diameter of the World-Wide Web | journal=Nature | volume=401 | issue=6749 | year=1999 | issn=0028-0836 | doi=10.1038/43601 | pages=130–131| arxiv=cond-mat/9907038 | s2cid=4419938 }}</ref> World Trade Web,<ref name=reciporcity4>{{cite journal | last1=Garlaschelli | first1=Diego | last2=Loffredo | first2=Maria I. | title=Fitness-Dependent Topological Properties of the World Trade Web | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=93 | issue=18 | date=2004-10-28 | issn=0031-9007 | doi=10.1103/physrevlett.93.188701 | page=188701| pmid=15525215 | arxiv=cond-mat/0403051 | s2cid=16367275 }}</ref> or Wikipedia<ref name=reciporcity6>{{cite journal | last1=Zlatić | first1=V. | last2=Božičević | first2=M. | last3=Štefančić | first3=H. | last4=Domazet | first4=M. | title=Wikipedias: Collaborative web-based encyclopedias as complex networks | journal=Physical Review E | volume=74 | issue=1 | date=2006-07-24 | issn=1539-3755 | doi=10.1103/physreve.74.016115 | page=016115| pmid=16907159 | arxiv=physics/0602149 | s2cid=3388193 }}</ref> ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the [[clustering coefficient]]). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<ref name="gl04"/><br />
<br />
reasons. First, in the networks that transport information or material (such as email networks, World Wide Web (WWW), World Trade Web, or Wikipedia ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the clustering coefficient). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<br />
<br />
原因。首先,在传输信息或材料的网络(如电子邮件网络、万维网(WWW)、世界贸易网或维基百科)中,相互联系促进了传输过程。其次,在分析有向网络时,为了简单起见,人们通常将其视为无向网络;因此,从互惠性研究中获得的信息有助于估计将有向网络视为无向网络时引入的误差(例如,在测量聚类系数时)。最后,检测非凡的互惠模式可以揭示形成观察到的网络拓扑的可能机制和组织原则。<br />
<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
[ math > r = frac { l ^ { <-> }{ l } </math > <br />
<br />
==How is it defined?它是如何定义的?==<br />
<br />
===Traditional definition传统定义===<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
根据这个定义,r = 1是一个纯粹的双向网络,而<br />
<br />
A traditional way to define the reciprocity r is using the ratio of the number of links pointing in both directions <math>L^{<->}</math> to the total number of links L <ref name=reciporcity5>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref><br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
<br />
对于一个单向的人来说。实际网络的中间值介于0和1之间。<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
<br />
然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
根据这个定义,r=1表示纯双向网络,r=0表示纯单向的。实际网络的中间值介于0和1之间。<br />
<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
为了克服上述定义的缺陷,加拉舍利和洛弗雷多将互惠性定义为有向图的邻接矩阵项之间的相关系数a{ij}=1如果存在从i到j的链接,如果不存在,a{ij}=0:<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
(a { ji }-bar { a }){ sum { i neq }(a { ij }-bar { a })}(sum { i neq }(a { ij }-bar { a }) ^/math > ,<br />
<br />
===Garlaschelli and Loffredo's definition 加拉舍利和洛弗雷多的定义===<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
为了克服上述定义的缺陷,加拉舍利和洛弗雷多将互惠性定义为有向图的邻接矩阵项之间的相关系数a{ij}。如果存在从i到j的链接,a{ij}=1,如果不存在,a{ij}=0:其中平均值a¯≡∑i≠jaijN(N−1)=LN(N−1)。 <br />
<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
bar{a}测量观察到的与可能的有向链路的比率(链路密度) ,自链路现在被排除在l之外,因为 i 不等于 j。<br />
<br />
<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
The definition can be written in the following simple form:<br />
<br />
定义可以用以下简单的形式写出:<br />
<br />
<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a }} </math > <br />
<br />
<br />
<br />
The definition can be written in the following simple form:<br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络ρ>0和反互惠网络ρ<0,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
如果所有的链接都是相互的,那么如果r=0, ρ=ρmin. 。<br />
<br />
<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a } </math > <br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络ρ>0和反互惠网络ρ<0,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
这是使用ρ的另一个优点,因为它包含了这样一个思想,即在密度较大的网络中,完全反精确更具统计意义,而在稀疏网络中,它则被视为不太明显的效果。<br />
<br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<br />
<br />
在一些真实的社会网络中,Gallos 对这种互惠关系进行了分析。<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
这是使用ρ的另一个优点,因为它包含了这样一个思想,即在密度较大的网络中,完全反精确更具统计意义,而在稀疏网络中,它则被视为不太明显的效果。<br />
<br />
===Reciprocity in real social networks真实社会网络中的互惠性===<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<ref name="GallosRybski2012">{{cite journal|author=Gallos, Lazaros K.|author2=Rybski, Diego|author3=[[Fredrik Liljeros]]|author4=[[Shlomo Havlin]]|author5=Makse, Hernán A.|title=How People Interact in Evolving Online Affiliation Networks|journal=Physical Review X|volume=2|issue=3|year=2012|page=031014|issn=2160-3308|oclc=969762960|doi=10.1103/PhysRevX.2.031014|arxiv=1111.5534|s2cid=16905579}}</ref><br />
<br />
加洛斯分析了现实社会网络中的互惠性。<br />
<br />
Category:Computer networking<br />
<br />
类别: 计算机网络<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Reciprocity (network science)]]. Its edit history can be viewed at [[互惠性/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%BA%92%E6%83%A0%E6%80%A7&diff=21004互惠性2021-01-20T03:39:25Z<p>Henry:/* How is it defined? */</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Network Science}}<br />
<br />
In [[network science]], '''reciprocity''' is a measure of the likelihood of [[vertex (graph theory)|vertices]] in a [[directed graph|directed network]] to be mutually linked.<ref name="gl04">{{cite journal|title=Patterns of Link Reciprocity in Directed Networks|author=[[Diego Garlaschelli]]|author2=Loffredo, Maria I.|journal=Physical Review Letters|volume=93|issue=26|date=December 2004|page=268701|publisher=[[American Physical Society]]|doi=10.1103/PhysRevLett.93.268701|pmid=15698035|arxiv=cond-mat/0404521|s2cid=1043766}}</ref> Like the [[clustering coefficient]], [[scale-free network|scale-free]] [[degree distribution]], or [[community structure]], reciprocity is a quantitative measure used to study [[complex network]]s.<br />
<br />
In network science, reciprocity is a measure of the likelihood of vertices in a directed network to be mutually linked. Like the clustering coefficient, scale-free degree distribution, or community structure, reciprocity is a quantitative measure used to study complex networks.<br />
<br />
在网络科学中,互惠性是一种度量有向网络中顶点相互连接的可能性的方法。就像集聚系数、无标度分布或者社区结构一样,互惠性是一种用于研究复杂网络的定量度量。<br />
<br />
<br />
<br />
==Motivation动机==<br />
<br />
In real network problems, people are interested in determining the [[likelihood]] of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
In real network problems, people are interested in determining the likelihood of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
在实际的网络问题中,人们感兴趣的是确定顶点对之间发生双链接(方向相反)的可能性。这个问题对许多人来说都是根本问题<br />
<br />
reasons. First, in the networks that transport information or material (such as email networks,<ref name=reciporcity2>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref> World Wide Web (WWW),<ref name=reciporcity3>{{cite journal | last1=Albert | first1=Réka | last2=Jeong | first2=Hawoong | last3=Barabási | first3=Albert-László | title=Diameter of the World-Wide Web | journal=Nature | volume=401 | issue=6749 | year=1999 | issn=0028-0836 | doi=10.1038/43601 | pages=130–131| arxiv=cond-mat/9907038 | s2cid=4419938 }}</ref> World Trade Web,<ref name=reciporcity4>{{cite journal | last1=Garlaschelli | first1=Diego | last2=Loffredo | first2=Maria I. | title=Fitness-Dependent Topological Properties of the World Trade Web | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=93 | issue=18 | date=2004-10-28 | issn=0031-9007 | doi=10.1103/physrevlett.93.188701 | page=188701| pmid=15525215 | arxiv=cond-mat/0403051 | s2cid=16367275 }}</ref> or Wikipedia<ref name=reciporcity6>{{cite journal | last1=Zlatić | first1=V. | last2=Božičević | first2=M. | last3=Štefančić | first3=H. | last4=Domazet | first4=M. | title=Wikipedias: Collaborative web-based encyclopedias as complex networks | journal=Physical Review E | volume=74 | issue=1 | date=2006-07-24 | issn=1539-3755 | doi=10.1103/physreve.74.016115 | page=016115| pmid=16907159 | arxiv=physics/0602149 | s2cid=3388193 }}</ref> ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the [[clustering coefficient]]). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<ref name="gl04"/><br />
<br />
reasons. First, in the networks that transport information or material (such as email networks, World Wide Web (WWW), World Trade Web, or Wikipedia ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the clustering coefficient). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<br />
<br />
原因。首先,在传输信息或材料的网络(如电子邮件网络、万维网(WWW)、世界贸易网或维基百科)中,相互联系促进了传输过程。其次,在分析有向网络时,为了简单起见,人们通常将其视为无向网络;因此,从互惠性研究中获得的信息有助于估计将有向网络视为无向网络时引入的误差(例如,在测量聚类系数时)。最后,检测非凡的互惠模式可以揭示形成观察到的网络拓扑的可能机制和组织原则。<br />
<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
[ math > r = frac { l ^ { <-> }{ l } </math > <br />
<br />
==How is it defined?它是如何定义的?==<br />
<br />
===Traditional definition传统定义===<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
根据这个定义,r = 1是一个纯粹的双向网络,而<br />
<br />
A traditional way to define the reciprocity r is using the ratio of the number of links pointing in both directions <math>L^{<->}</math> to the total number of links L <ref name=reciporcity5>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref><br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
<br />
对于一个单向的人来说。实际网络的中间值介于0和1之间。<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
<br />
然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
根据这个定义,r=1表示纯双向网络,r=0表示纯单向的。实际网络的中间值介于0和1之间。<br />
<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
为了克服上述定义的缺陷,加拉舍利和洛弗雷多将互惠性定义为有向图的邻接矩阵项之间的相关系数a{ij}=1如果存在从i到j的链接,如果不存在,a{ij}=0:<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
(a { ji }-bar { a }){ sum { i neq }(a { ij }-bar { a })}(sum { i neq }(a { ij }-bar { a }) ^/math > ,<br />
<br />
===Garlaschelli and Loffredo's definition 加拉舍利和洛弗雷多的定义===<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
为了克服上述定义的缺陷,加拉舍利和洛弗雷多将互惠性定义为有向图的邻接矩阵项之间的相关系数a{ij}。如果存在从i到j的链接,a{ij}=1,如果不存在,a{ij}=0:其中平均值a¯≡∑i≠jaijN(N−1)=LN(N−1)。 <br />
<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
bar{a}测量观察到的与可能的有向链路的比率(链路密度) ,自链路现在被排除在l之外,因为 i 不等于 j。<br />
<br />
<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
The definition can be written in the following simple form:<br />
<br />
定义可以用以下简单的形式写出:<br />
<br />
<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a }} </math > <br />
<br />
<br />
<br />
The definition can be written in the following simple form:<br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络ρ>0和反互惠网络ρ<0,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
如果所有的链接都是相互的,那么如果r=0, ρ=ρmin. 。<br />
<br />
<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a } </math > <br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络ρ>0和反互惠网络ρ<0,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
这是使用ρ的另一个优点,因为它包含了这样一个思想,即在密度较大的网络中,完全反精确更具统计意义,而在稀疏网络中,它则被视为不太明显的效果。<br />
<br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<br />
<br />
在一些真实的社会网络中,Gallos 对这种互惠关系进行了分析。<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
这是使用ρ的另一个优点,因为它包含了这样一个思想,即在密度较大的网络中,完全反精确更具统计意义,而在稀疏网络中,它则被视为不太明显的效果。<br />
<br />
===Reciprocity in real social networks真实社会网络中的互惠性===<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<ref name="GallosRybski2012">{{cite journal|author=Gallos, Lazaros K.|author2=Rybski, Diego|author3=[[Fredrik Liljeros]]|author4=[[Shlomo Havlin]]|author5=Makse, Hernán A.|title=How People Interact in Evolving Online Affiliation Networks|journal=Physical Review X|volume=2|issue=3|year=2012|page=031014|issn=2160-3308|oclc=969762960|doi=10.1103/PhysRevX.2.031014|arxiv=1111.5534|s2cid=16905579}}</ref><br />
<br />
<br />
<br />
Category:Computer networking<br />
<br />
类别: 计算机网络<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Reciprocity (network science)]]. Its edit history can be viewed at [[互惠性/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%BA%92%E6%83%A0%E6%80%A7&diff=21003互惠性2021-01-20T03:21:33Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Network Science}}<br />
<br />
In [[network science]], '''reciprocity''' is a measure of the likelihood of [[vertex (graph theory)|vertices]] in a [[directed graph|directed network]] to be mutually linked.<ref name="gl04">{{cite journal|title=Patterns of Link Reciprocity in Directed Networks|author=[[Diego Garlaschelli]]|author2=Loffredo, Maria I.|journal=Physical Review Letters|volume=93|issue=26|date=December 2004|page=268701|publisher=[[American Physical Society]]|doi=10.1103/PhysRevLett.93.268701|pmid=15698035|arxiv=cond-mat/0404521|s2cid=1043766}}</ref> Like the [[clustering coefficient]], [[scale-free network|scale-free]] [[degree distribution]], or [[community structure]], reciprocity is a quantitative measure used to study [[complex network]]s.<br />
<br />
In network science, reciprocity is a measure of the likelihood of vertices in a directed network to be mutually linked. Like the clustering coefficient, scale-free degree distribution, or community structure, reciprocity is a quantitative measure used to study complex networks.<br />
<br />
在网络科学中,互惠性是一种度量有向网络中顶点相互连接的可能性的方法。就像集聚系数、无标度分布或者社区结构一样,互惠性是一种用于研究复杂网络的定量度量。<br />
<br />
<br />
<br />
==Motivation动机==<br />
<br />
In real network problems, people are interested in determining the [[likelihood]] of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
In real network problems, people are interested in determining the likelihood of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
在实际的网络问题中,人们感兴趣的是确定顶点对之间发生双链接(方向相反)的可能性。这个问题对许多人来说都是根本问题<br />
<br />
reasons. First, in the networks that transport information or material (such as email networks,<ref name=reciporcity2>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref> World Wide Web (WWW),<ref name=reciporcity3>{{cite journal | last1=Albert | first1=Réka | last2=Jeong | first2=Hawoong | last3=Barabási | first3=Albert-László | title=Diameter of the World-Wide Web | journal=Nature | volume=401 | issue=6749 | year=1999 | issn=0028-0836 | doi=10.1038/43601 | pages=130–131| arxiv=cond-mat/9907038 | s2cid=4419938 }}</ref> World Trade Web,<ref name=reciporcity4>{{cite journal | last1=Garlaschelli | first1=Diego | last2=Loffredo | first2=Maria I. | title=Fitness-Dependent Topological Properties of the World Trade Web | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=93 | issue=18 | date=2004-10-28 | issn=0031-9007 | doi=10.1103/physrevlett.93.188701 | page=188701| pmid=15525215 | arxiv=cond-mat/0403051 | s2cid=16367275 }}</ref> or Wikipedia<ref name=reciporcity6>{{cite journal | last1=Zlatić | first1=V. | last2=Božičević | first2=M. | last3=Štefančić | first3=H. | last4=Domazet | first4=M. | title=Wikipedias: Collaborative web-based encyclopedias as complex networks | journal=Physical Review E | volume=74 | issue=1 | date=2006-07-24 | issn=1539-3755 | doi=10.1103/physreve.74.016115 | page=016115| pmid=16907159 | arxiv=physics/0602149 | s2cid=3388193 }}</ref> ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the [[clustering coefficient]]). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<ref name="gl04"/><br />
<br />
reasons. First, in the networks that transport information or material (such as email networks, World Wide Web (WWW), World Trade Web, or Wikipedia ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the clustering coefficient). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<br />
<br />
原因。首先,在传输信息或材料的网络(如电子邮件网络、万维网(WWW)、世界贸易网或维基百科)中,相互联系促进了传输过程。其次,在分析有向网络时,为了简单起见,人们通常将其视为无向网络;因此,从互惠性研究中获得的信息有助于估计将有向网络视为无向网络时引入的误差(例如,在测量聚类系数时)。最后,检测非凡的互惠模式可以揭示形成观察到的网络拓扑的可能机制和组织原则。<br />
<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
[ math > r = frac { l ^ { <-> }{ l } </math > <br />
<br />
==How is it defined?==<br />
<br />
===Traditional definition传统定义===<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
根据这个定义,r = 1是一个纯粹的双向网络,而<br />
<br />
A traditional way to define the reciprocity r is using the ratio of the number of links pointing in both directions <math>L^{<->}</math> to the total number of links L <ref name=reciporcity5>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref><br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
<br />
对于一个单向的人来说。实际网络的中间值介于0和1之间。<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
<br />
然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
根据这个定义,r=1表示纯双向网络,r=0表示纯单向的。实际网络的中间值介于0和1之间。<br />
<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
为了克服上述定义的缺陷,Garlaschelli和Loffredo将互惠性定义为有向图的邻接矩阵项之间的相关系数a{ij}=1如果存在从i到j的链接,如果不存在,a{ij}=0:<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
然而,这种互惠的定义也有一些缺陷。与具有相同顶点和边数的纯随机网络相比,它无法分辨互惠性的相对差异。从互惠中得到的有用信息不是价值本身,而是相互联系发生的频率是否比偶然预期的要高。此外,在含有自联环的网络中(在同一顶点开始和结束的链接),计算L时应排除自联环<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
(a { ji }-bar { a }){ sum { i neq }(a { ij }-bar { a })}(sum { i neq }(a { ij }-bar { a }) ^/math > ,<br />
<br />
===Garlaschelli and Loffredo's definition===<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
其中平均值 < math > bar { a } equiv frac { sum { i neq } a { ij }{ n (N-1)} = frac { l }{ n (N-1)}} </math > 。<br />
<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
测量观察到的与可能的有向链路的比率(链路密度) ,自链路现在被排除在 l 之外,因为 i 不等于 j。<br />
<br />
<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
The definition can be written in the following simple form:<br />
<br />
定义可以用以下简单的形式写出:<br />
<br />
<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a }} </math > <br />
<br />
<br />
<br />
The definition can be written in the following simple form:<br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络(< math > rho > 0 </math >)和反互惠网络(< math > rho < 0 </math >) ,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
如果所有的链接都是相互的,那么如果 r = 0,那么 rho = rho _ { min } </math > 。<br />
<br />
<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a } </math > <br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
<br />
<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
<br />
这是使用 < math > rho </math > 的另一个优点,因为它包含了这样一个概念,即完全反互惠在密度较大的网络中更具统计学意义,而在较为稀疏的网络中则不那么显著。<br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<br />
<br />
在一些真实的社会网络中,Gallos 对这种互惠关系进行了分析。<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
<br />
<br />
<br />
===Reciprocity in real social networks===<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<ref name="GallosRybski2012">{{cite journal|author=Gallos, Lazaros K.|author2=Rybski, Diego|author3=[[Fredrik Liljeros]]|author4=[[Shlomo Havlin]]|author5=Makse, Hernán A.|title=How People Interact in Evolving Online Affiliation Networks|journal=Physical Review X|volume=2|issue=3|year=2012|page=031014|issn=2160-3308|oclc=969762960|doi=10.1103/PhysRevX.2.031014|arxiv=1111.5534|s2cid=16905579}}</ref><br />
<br />
<br />
<br />
Category:Computer networking<br />
<br />
类别: 计算机网络<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Reciprocity (network science)]]. Its edit history can be viewed at [[互惠性/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%BA%92%E6%83%A0%E6%80%A7&diff=21002互惠性2021-01-20T03:13:17Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Network Science}}<br />
<br />
In [[network science]], '''reciprocity''' is a measure of the likelihood of [[vertex (graph theory)|vertices]] in a [[directed graph|directed network]] to be mutually linked.<ref name="gl04">{{cite journal|title=Patterns of Link Reciprocity in Directed Networks|author=[[Diego Garlaschelli]]|author2=Loffredo, Maria I.|journal=Physical Review Letters|volume=93|issue=26|date=December 2004|page=268701|publisher=[[American Physical Society]]|doi=10.1103/PhysRevLett.93.268701|pmid=15698035|arxiv=cond-mat/0404521|s2cid=1043766}}</ref> Like the [[clustering coefficient]], [[scale-free network|scale-free]] [[degree distribution]], or [[community structure]], reciprocity is a quantitative measure used to study [[complex network]]s.<br />
<br />
In network science, reciprocity is a measure of the likelihood of vertices in a directed network to be mutually linked. Like the clustering coefficient, scale-free degree distribution, or community structure, reciprocity is a quantitative measure used to study complex networks.<br />
<br />
在网络科学中,互惠性是一种度量有向网络中顶点相互连接的可能性的方法。就像集聚系数、无标度分布或者社区结构一样,互惠性是一种用于研究复杂网络的定量度量。<br />
<br />
<br />
<br />
==Motivation动机==<br />
<br />
In real network problems, people are interested in determining the [[likelihood]] of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
In real network problems, people are interested in determining the likelihood of occurring double links (with opposite directions) between vertex pairs. This problem is fundamental for several<br />
<br />
在真实的网络问题中,人们感兴趣的是确定顶点对之间出现双链路(方向相反)的可能性。这个问题对一些人来说是根本性的<br />
<br />
reasons. First, in the networks that transport information or material (such as email networks,<ref name=reciporcity2>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref> World Wide Web (WWW),<ref name=reciporcity3>{{cite journal | last1=Albert | first1=Réka | last2=Jeong | first2=Hawoong | last3=Barabási | first3=Albert-László | title=Diameter of the World-Wide Web | journal=Nature | volume=401 | issue=6749 | year=1999 | issn=0028-0836 | doi=10.1038/43601 | pages=130–131| arxiv=cond-mat/9907038 | s2cid=4419938 }}</ref> World Trade Web,<ref name=reciporcity4>{{cite journal | last1=Garlaschelli | first1=Diego | last2=Loffredo | first2=Maria I. | title=Fitness-Dependent Topological Properties of the World Trade Web | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=93 | issue=18 | date=2004-10-28 | issn=0031-9007 | doi=10.1103/physrevlett.93.188701 | page=188701| pmid=15525215 | arxiv=cond-mat/0403051 | s2cid=16367275 }}</ref> or Wikipedia<ref name=reciporcity6>{{cite journal | last1=Zlatić | first1=V. | last2=Božičević | first2=M. | last3=Štefančić | first3=H. | last4=Domazet | first4=M. | title=Wikipedias: Collaborative web-based encyclopedias as complex networks | journal=Physical Review E | volume=74 | issue=1 | date=2006-07-24 | issn=1539-3755 | doi=10.1103/physreve.74.016115 | page=016115| pmid=16907159 | arxiv=physics/0602149 | s2cid=3388193 }}</ref> ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the [[clustering coefficient]]). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<ref name="gl04"/><br />
<br />
reasons. First, in the networks that transport information or material (such as email networks, World Wide Web (WWW), World Trade Web, or Wikipedia ), mutual links facilitate the transportation process. Second, when analyzing directed networks, people often treat them as undirected ones for simplicity; therefore, the information obtained from reciprocity studies helps to estimate the error introduced when a directed network is treated as undirected (for example, when measuring the clustering coefficient). Finally, detecting nontrivial patterns of reciprocity can reveal possible mechanisms and organizing principles that shape the observed network's topology.<br />
<br />
原因。首先,在传输信息或材料的网络(如电子邮件网络、万维网、世界贸易网络或维基百科)中,相互链接促进了传输过程。其次,在分析有向网络时,为了简单起见,人们通常将其视为无向网络; 因此,从互易性研究中获得的信息有助于估计有向网络被视为无向网络时引入的误差(例如,在测量集聚系数时)。最后,检测非平凡的互易模式可以揭示可能的机制和组织原则,形成观察网络的拓扑结构。<br />
<br />
<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
[ math > r = frac { l ^ { <-> }{ l } </math > <br />
<br />
==How is it defined?==<br />
<br />
===Traditional definition===<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
根据这个定义,< math > r = 1 </math > 是一个纯粹的双向网络,而<br />
<br />
A traditional way to define the reciprocity r is using the ratio of the number of links pointing in both directions <math>L^{<->}</math> to the total number of links L <ref name=reciporcity5>{{cite journal | last1=Newman | first1=M. E. J. | last2=Forrest | first2=Stephanie | last3=Balthrop | first3=Justin | title=Email networks and the spread of computer viruses | journal=Physical Review E | publisher=American Physical Society (APS) | volume=66 | issue=3 | date=2002-09-10 | issn=1063-651X | doi=10.1103/physreve.66.035101 | page=035101(R)| pmid=12366169 }}</ref><br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
<br />
对于一个单向的人来说。实际网络的中间值介于0和1之间。<br />
<br />
<math>r = \frac {L^{<->}}{L}</math><br />
<br />
<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
<br />
然而,这种互惠的定义有一些缺陷。与纯随机网络相比,在顶点和边数相同的情况下,不能区分互易性的相对差别。来自互惠的有用信息不是价值本身,而是相互联系是否比偶然发生的频率高或低。此外,在含有自链路的网络中(链路起始和终止于同一顶点) ,在计算 l 时应该排除自链路。<br />
<br />
With this definition, <math>r = 1</math> is for a purely bidirectional network while<br />
<br />
<math>r = 0 </math> for a purely unidirectional one. Real networks have an intermediate value between 0 and 1.<br />
<br />
<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
为了克服上述定义的缺陷,Garlaschelli 和 Loffredo 将互易性定义为一个有向图的邻接矩阵条目之间的相关系数(如果存在从 i 到 j 的链接,如果不存在,则相关系数为 a { ij } = 0 </math >) :<br />
<br />
However, this definition of reciprocity has some defects. It cannot tell the relative difference of reciprocity compared with purely random network with the same number of vertices and edges. The useful information from reciprocity is not the value itself, but whether mutual links occur more or less often than expected by chance. Besides, in those networks containing self-linking loops (links starting and ending at the same vertex), the self-linking loops should be excluded when calculating L.<br />
<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
(a { ji }-bar { a }){ sum { i neq }(a { ij }-bar { a })}(sum { i neq }(a { ij }-bar { a }) ^/math > ,<br />
<br />
===Garlaschelli and Loffredo's definition===<br />
<br />
In order to overcome the defects of the above definition, Garlaschelli and Loffredo defined reciprocity as the correlation coefficient between the entries of the adjacency matrix of a directed graph (<math>a_{ij} = 1</math> if a link from i to j is there, and <math>a_{ij} = 0</math> if not):<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
其中平均值 < math > bar { a } equiv frac { sum { i neq } a { ij }{ n (N-1)} = frac { l }{ n (N-1)}} </math > 。<br />
<br />
<br />
<br />
<math>\rho \equiv \frac {\sum_{i \neq j} (a_{ij} - \bar{a}) (a_{ji} - \bar{a})}{\sum_{i \neq j} (a_{ij} - \bar{a})^2}</math>,<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
测量观察到的与可能的有向链路的比率(链路密度) ,自链路现在被排除在 l 之外,因为 i 不等于 j。<br />
<br />
<br />
<br />
where the average value <math>\bar{a} \equiv \frac {\sum_{i \neq j} a_{ij}} {N(N-1)} = \frac {L} {N(N-1)}</math>.<br />
<br />
The definition can be written in the following simple form:<br />
<br />
定义可以用以下简单的形式写出:<br />
<br />
<br />
<br />
<math>\bar{a}</math> measures the ratio of observed to possible directed links (link density), and self-linking loops are now excluded from L because of i not equal to j.<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a }} </math > <br />
<br />
<br />
<br />
The definition can be written in the following simple form:<br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
<br />
互惠的新定义给出了一个绝对量,这个绝对量直接允许人们区分互惠网络(< math > rho > 0 </math >)和反互惠网络(< math > rho < 0 </math >) ,相互联系比随机网络发生的频率更高、更少。<br />
<br />
<br />
<br />
<math>\rho = \frac {r - \bar{a}} {1- \bar{a}}</math><br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
如果所有的链接都是相互的,那么如果 r = 0,那么 rho = rho _ { min } </math > 。<br />
<br />
<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
1-bar { a } </math > <br />
<br />
The new definition of reciprocity gives an absolute quantity which directly allows one to distinguish between reciprocal (<math>\rho > 0</math>) and antireciprocal (<math>\rho < 0</math>) networks, with mutual links occurring more and less often than random respectively.<br />
<br />
<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
<br />
这是使用 < math > rho </math > 的另一个优点,因为它包含了这样一个概念,即完全反互惠在密度较大的网络中更具统计学意义,而在较为稀疏的网络中则不那么显著。<br />
<br />
If all the links occur in reciprocal pairs, <math>\rho = 1</math>; if r=0, <math>\rho = \rho_{min}</math>.<br />
<br />
<math>\rho_{min} \equiv \frac {- \bar{a}} {1- \bar{a}}</math><br />
<br />
<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<br />
<br />
在一些真实的社会网络中,Gallos 对这种互惠关系进行了分析。<br />
<br />
This is another advantage of using <math>\rho</math>, because it incorporates the idea that complete antireciprocal is more statistical significant in the networks with larger density, while it has to be regarded as a less pronounced effect in sparser networks.<br />
<br />
<br />
<br />
===Reciprocity in real social networks===<br />
<br />
The reciprocity was analyzed in some real social networks by Gallos.<ref name="GallosRybski2012">{{cite journal|author=Gallos, Lazaros K.|author2=Rybski, Diego|author3=[[Fredrik Liljeros]]|author4=[[Shlomo Havlin]]|author5=Makse, Hernán A.|title=How People Interact in Evolving Online Affiliation Networks|journal=Physical Review X|volume=2|issue=3|year=2012|page=031014|issn=2160-3308|oclc=969762960|doi=10.1103/PhysRevX.2.031014|arxiv=1111.5534|s2cid=16905579}}</ref><br />
<br />
<br />
<br />
Category:Computer networking<br />
<br />
类别: 计算机网络<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Reciprocity (network science)]]. Its edit history can be viewed at [[互惠性/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%94%9F%E6%88%90%E7%A7%91%E5%AD%A6&diff=21001生成科学2021-01-20T02:48:03Z<p>Henry:/* Scientific and philosophical origins科学哲学渊源 */</p>
<hr />
<div>此词条暂由Henry翻译。<br />
<br />
{{short description|Study of how complex behaviour can be generated by deterministic and finite rules and parameters}}<br />
<br />
[[File:Game of life torus 100 100 1500.gif|right|500px|thumb|Interaction between a few simple rules and parameters can produce endless, seemingly unpredictable complexity.]]<br />
<br />
Interaction between a few simple rules and parameters can produce endless, seemingly unpredictable complexity.<br />
<br />
几个简单规则和参数之间的交互可以产生无穷无尽的、似乎无法预测的复杂性。<br />
<br />
<br />
<br />
'''Generative science''' is an area of research that explores the natural [[world]] and its complex behaviours. It explores ways "to generate apparently unanticipated and infinite behaviour based on [[Deterministic automaton|deterministic]] and [[Finite-state machine|finite]] rules and parameters reproducing or resembling the behavior of natural and social phenomena".<ref>{{citation |page=7 |chapter=Computing Nature – A Network of Networks of Concurrent Information Processes |author1=Gordana Dodig-Crnkovic |author2=Raffaela Giovagnoli |title=Computing nature: Turing centenary perspective |publisher=Springer |year=2013 |editor1=Gordana Dodig-Crnkovic |editor2=Raffaela Giovagnoli |isbn=978-3-642-37225-4}}</ref> By modelling such interactions, it can suggest that properties exist in the system that had not been noticed in the real world situation.<ref name= "Ning">{{citation |authors=Ning Nan, Erik W. Johnston, Judith S. Olson |year=2008 |title=Unintended consequences of collocation: using agent-based modeling to untangle effects of communication delay and in-group favor |journal=Computational & Mathematical Organization Theory |volume=14 |issue=2 |pages=57–83 |doi=10.1007/s10588-008-9024-4}}</ref> An example field of study is how [[unintended consequences]] arise in social processes.<br />
<br />
Generative science is an area of research that explores the natural world and its complex behaviours. It explores ways "to generate apparently unanticipated and infinite behaviour based on deterministic and finite rules and parameters reproducing or resembling the behavior of natural and social phenomena". By modelling such interactions, it can suggest that properties exist in the system that had not been noticed in the real world situation. An example field of study is how unintended consequences arise in social processes.<br />
<br />
生成科学是探索自然世界及其复杂行为的研究领域。它探索了“基于再现或类似自然和社会现象行为的确定性和有限性规则和参数,产生明显出乎意料和无限的行为”的方法。通过对这种相互作用进行建模,它可以表明系统中存在着在现实世界中没有注意到的特性。研究领域的一个例子是研究社会过程中如何产生出乎意料的结果。 <br />
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Generative sciences often explore natural phenomena at several levels of organization.<ref>{{Cite journal | last1 = Farre | first1 = G. L. | title = The Energetic Structure of Observation: A Philosophical Disquisition | doi = 10.1177/0002764297040006004 | journal = American Behavioral Scientist | volume = 40 | issue = 6 | pages = 717–728 | year = 1997 | pmid = | pmc = }}</ref><ref name= "Schmidhuber">J. Schmidhuber. (1997) [https://arxiv.org/abs/quant-ph/9904050 A computer scientist's view of life, the universe, and everything]. Foundations of Computer Science: Potential – Theory – Cognition, Lecture Notes in Computer Science, pages 201–208, Springer</ref> [[Self-organization|Self-organizing]] natural systems are a central subject, studied both theoretically and by simulation experiments. The study of complex systems in general has been grouped under the heading of "[[general systems theory]]", particularly by [[Ludwig von Bertalanffy]], [[Anatol Rapoport]], [[Ralph Gerard]], and [[Kenneth Boulding]].<br />
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Generative sciences often explore natural phenomena at several levels of organization. Self-organizing natural systems are a central subject, studied both theoretically and by simulation experiments. The study of complex systems in general has been grouped under the heading of "general systems theory", particularly by Ludwig von Bertalanffy, Anatol Rapoport, Ralph Gerard, and Kenneth Boulding.<br />
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生成科学经常在组织的几个层次上探索自然现象。自组织自然系统是一个重要的研究课题,无论是理论研究还是仿真实验都是如此。一般来说,复杂系统的研究被归在“一般系统理论”的课题下,代表人物有路德维希·冯·贝尔塔兰菲、阿纳托尔·拉波波特、拉尔夫·杰拉德和肯尼斯·博尔丁。<br />
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These sciences include [[psychology]] and [[cognitive science]], [[cellular automata]], [[generative linguistics]], [[natural language processing]], [[connectionism]], [[self-organization]], [[evolutionary biology]], [[neural network]], [[social network]], [[Cognitive musicology|neuromusicology]], [[quantum cellular automata]], [[information theory]], [[systems theory]], [[genetic algorithm]]s, [[computational sociology]], [[Telecommunications network|communication networks]], [[artificial life]], [[chaos theory]], [[Complex systems|complexity theory]], [[network science]], [[epistemology]], [[quantum dot cellular automaton]], [[quantum computer]], [[systems thinking]], [[genetics]], [[economy]], [[philosophy of science]], [[quantum mechanics]], [[cybernetics]], [[digital physics]], [[digital philosophy]], [[bioinformatics]], [[agent-based model]]ing and [[catastrophe theory]].<br />
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These sciences include psychology and cognitive science, cellular automata, generative linguistics, natural language processing, connectionism, self-organization, evolutionary biology, neural network, social network, neuromusicology, quantum cellular automata, information theory, systems theory, genetic algorithms, computational sociology, communication networks, artificial life, chaos theory, complexity theory, network science, epistemology, quantum dot cellular automaton, quantum computer, systems thinking, genetics, economy, philosophy of science, quantum mechanics, cybernetics, digital physics, digital philosophy, bioinformatics, agent-based modeling and catastrophe theory.<br />
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这些科学包括心理学和认知科学、细胞自动机、生成语言学、自然语言处理、连接主义、自我组织、进化生物学、神经网络、社会网络、神经音乐学、量子细胞自动机、信息论、系统论、遗传算法、计算社会学、通信网络、人工生命、混沌理论、复杂性理论、网络科学、认识论、量子点细胞自动机、量子计算机、系统思维、遗传学、经济学、科学哲学、量子力学、控制论、数字物理学、数字哲学、生物信息学、基于代理的建模和灾难理论。<br />
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==Scientific and philosophical origins科学哲学渊源==<br />
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[[File:Airplane vortex edit.jpg|thumb|[[Turbulence]] in the [[Wingtip vortices|tip vortex]] from an [[airplane]] wing. Studies of the critical point beyond which a system creates turbulence were important for [[chaos theory]], analyzed for example by the [[Soviet physicists|Soviet physicist]] [[Lev Landau]] who developed the [[Landau-Hopf theory of turbulence]]. [[David Ruelle]] and [[Floris Takens]] later predicted, against Landau, that [[fluid turbulence]] could develop through a [[strange attractor]], a main concept of chaos theory.]]<br />
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[[Turbulence in the tip vortex from an airplane wing. Studies of the critical point beyond which a system creates turbulence were important for chaos theory, analyzed for example by the Soviet physicist Lev Landau who developed the Landau-Hopf theory of turbulence. David Ruelle and Floris Takens later predicted, against Landau, that fluid turbulence could develop through a strange attractor, a main concept of chaos theory.]]<br />
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飞机机翼顶端涡流中的湍流。关于系统产生湍流的临界点的研究对于混沌理论非常重要,例如,苏联物理学家Lev Landau开发了Landau-Hopf湍流理论。大卫·鲁埃尔和弗洛里斯·塔肯斯后来预言,流体湍流可能通过一个奇怪的吸引子发展,而这个吸引子是混沌理论的主要概念。 <br />
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[[File:Forest of synthetic pyramidal dendrites grown using Cajal's laws of neuronal branching.png|thumb|200px|[[Computer simulation]] of the branching architecture of the [[dendrite]]s of [[pyramidal neuron]]s.<ref>{{Cite journal |author=Hermann Cuntz | doi = 10.1371/image.pcbi.v06.i08 | title = PLoS Computational Biology Issue Image &#124; Vol. 6(8) August 2010 | journal = PLOS Computational Biology | volume = 6 | issue = 8 | pages = ev06.ei08 | year = 2010 | pmid = | pmc = | doi-access = free }}</ref>]]<br />
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[[Computer simulation of the branching architecture of the dendrites of pyramidal neurons.]]<br />
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[大锥体神经元树突分支结构的计算机模拟]<br />
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[[File:Auklet flock Shumagins 1986.jpg|right|200px|thumb|The natural phenomenon of herd behaviour as in a flock of birds can be modelled artificially using simple rules in individual units, with [[swarm intelligence]] rather than any centralized control.]]<br />
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The natural phenomenon of herd behaviour as in a flock of birds can be modelled artificially using simple rules in individual units, with [[swarm intelligence rather than any centralized control.]]<br />
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群体行为的自然现象,如鸟群中的行为,可以用简单的个体规则,用群体智能而不是任何集中控制来人工模拟。<br />
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The development of computers and [[automata theory]] laid a technical foundation for the growth of the generative sciences. For example:<br />
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The development of computers and automata theory laid a technical foundation for the growth of the generative sciences. For example:<br />
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计算机和自动机理论的发展为生殖科学的发展奠定了技术基础。例如:<br />
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*[[Cellular automaton|Cellular automata]] are mathematical representations of simple entities interacting under [[determinism|deterministic]] rules to manifest complex behaviours. They can be used to model emergent processes of the physical universe, neural cognitive processes and social behavior.<ref name="Kenrick">{{cite journal | doi = 10.1037/0033-295X.110.1.3 | last1 = Kenrick | first1 = DT | last2 = Li | first2 = NP | last3 = Butner | first3 = J | title = Dynamical evolutionary psychology: individual decision rules and emergent social norms | journal = Psychological Review | volume = 110 | issue = 1 | pages = 3–28 | year = 2003 | pmid = 12529056 | citeseerx = 10.1.1.526.5218 }}</ref><ref name="EpsteinAxtell">{{cite book|first1=Joshua M.|last1=Epstein|authorlink1=Joshua M. Epstein|first2=Robert L.|last2=Axtell|authorlink2=Robert Axtell|year=1996|title=Growing Artificial Societies: Social Science From the Bottom Up|publisher=MIT/Brookings Institution|location=Cambridge MA|page=[https://archive.org/details/growingartificia00epst/page/224 224]|isbn=978-0-262-55025-3|url-access=registration|url=https://archive.org/details/growingartificia00epst/page/224}}</ref><ref name= "Nowak">{{citation |authors=Nowak A., Vallacher R.R., Tesser A., Borkowski W. |year=2000 |title=Society of Self: The emergence of collective properties in self-structure |journal=Psychological Review |volume=107 |issue=1 |pages=39–61 |pmid=10687402 |doi=10.1037/0033-295x.107.1.39}}</ref><ref name= "Epstein">{{citation |author=Epstein J.M. |year=1999 |title=Agent Based Computational Models and Generative Social Science |journal=Complexity |volume=4 |issue=5 |pages=41–60 |doi=10.1002/(SICI)1099-0526(199905/06)4:5<41::AID-CPLX9>3.0.CO;2-F|bibcode=1999Cmplx...4e..41E |citeseerx=10.1.1.353.5950 }}</ref><br />
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**[[Conway's Game of Life]] is a zero-player game based on cellular automata, meaning that the only input is in setting the initial conditions, and the game is to see how the system evolves.<ref>[http://www.bitstorm.org/gameoflife/ John Conway's Game of Life]</ref><br />
[Conway's Game of Life]]是一款基于元胞自动机的零人游戏,也就是说,唯一的输入是设置初始条件,游戏就是看系统如何进化 <br />
**In 1996 [[Joshua M. Epstein]] and [[Robert Axtell]] wrote the book ''Growing Artificial Societies'' which proposes a set of automaton rules and a system called ''[[Sugarscape]]'' which models a population dependent on resources (called sugar).<br />
1996年,[[约书亚M爱泼斯坦]]和[[罗伯特·阿克斯泰尔]]写了一本书《成长中的人工社会》,书中提出了一套自动化规则和一个名为“[[Sugarscape]]”的系统,该系统对依赖资源的人口(称为sugar)进行建模 <br />
*[[Artificial neural network]]s attempt to solve problems in the same way that the human brain would, although they are still several orders of magnitude less complex than the human brain and closer to the computing power of a worm. Advances in the understanding of the human brain often stimulate new patterns in neural networks.<br />
[[人工神经网络]]试图以人脑同样的方式解决问题,尽管它们的复杂程度仍比人脑低几个数量级,更接近蠕虫的计算能力。对人脑的理解的进步经常能够用来刺激生成神经网络的新模式。 <br />
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One of the most influential advances in the generative sciences as related to [[cognitive science]] came from [[Noam Chomsky]]'s (1957) development of [[generative grammar]], which separated language generation from semantic content, and thereby revealed important questions about human language. It was also in the early 1950s that psychologists at the MIT including [[Kurt Lewin]], [[Jacob Levy Moreno]] and [[Fritz Heider]] laid the foundations for [[group dynamics]] research which later developed into [[social network]] analysis.<br />
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One of the most influential advances in the generative sciences as related to cognitive science came from Noam Chomsky's (1957) development of generative grammar, which separated language generation from semantic content, and thereby revealed important questions about human language. It was also in the early 1950s that psychologists at the MIT including Kurt Lewin, Jacob Levy Moreno and Fritz Heider laid the foundations for group dynamics research which later developed into social network analysis.<br />
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与认知科学相关的生成科学中最具影响力的进展之一来自诺姆·乔斯基(1957)对生成语法的发展,它将语言生成与语义内容分离开来,从而揭示了有关人类语言的重要问题。同样是在20世纪50年代早期,麻省理工学院的心理学家库尔特·勒温、雅各布·利维·莫雷诺和弗里茨·海德为后来发展为社会网络分析的群体动力学研究奠定了基础。<br />
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== See also参见 ==<br />
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* {{annotated link|Generative systems}}<br />
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生成系统<br />
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==References参考==<br />
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{{Reflist|30em}}<br />
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==External links外部链接==<br />
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* http://www.swarthmore.edu/socsci/tburke1/artsoc.html (Artificial Societies, Virtual Worlds and the Shared Problems and Possibilities of Emergence)<br />
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* http://jasss.soc.surrey.ac.uk/JASSS.html (The Journal of Artificial Societies and Social Simulation)<br />
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[[Category:Systems theory]]<br />
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Category:Systems theory<br />
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范畴: 系统论<br />
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<small>This page was moved from [[wikipedia:en:Generative science]]. Its edit history can be viewed at [[生成科学/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%94%9F%E6%88%90%E7%A7%91%E5%AD%A6&diff=20918生成科学2021-01-16T11:27:18Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Study of how complex behaviour can be generated by deterministic and finite rules and parameters}}<br />
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[[File:Game of life torus 100 100 1500.gif|right|500px|thumb|Interaction between a few simple rules and parameters can produce endless, seemingly unpredictable complexity.]]<br />
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Interaction between a few simple rules and parameters can produce endless, seemingly unpredictable complexity.<br />
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几个简单规则和参数之间的交互可以产生无穷无尽的、似乎无法预测的复杂性。<br />
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'''Generative science''' is an area of research that explores the natural [[world]] and its complex behaviours. It explores ways "to generate apparently unanticipated and infinite behaviour based on [[Deterministic automaton|deterministic]] and [[Finite-state machine|finite]] rules and parameters reproducing or resembling the behavior of natural and social phenomena".<ref>{{citation |page=7 |chapter=Computing Nature – A Network of Networks of Concurrent Information Processes |author1=Gordana Dodig-Crnkovic |author2=Raffaela Giovagnoli |title=Computing nature: Turing centenary perspective |publisher=Springer |year=2013 |editor1=Gordana Dodig-Crnkovic |editor2=Raffaela Giovagnoli |isbn=978-3-642-37225-4}}</ref> By modelling such interactions, it can suggest that properties exist in the system that had not been noticed in the real world situation.<ref name= "Ning">{{citation |authors=Ning Nan, Erik W. Johnston, Judith S. Olson |year=2008 |title=Unintended consequences of collocation: using agent-based modeling to untangle effects of communication delay and in-group favor |journal=Computational & Mathematical Organization Theory |volume=14 |issue=2 |pages=57–83 |doi=10.1007/s10588-008-9024-4}}</ref> An example field of study is how [[unintended consequences]] arise in social processes.<br />
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Generative science is an area of research that explores the natural world and its complex behaviours. It explores ways "to generate apparently unanticipated and infinite behaviour based on deterministic and finite rules and parameters reproducing or resembling the behavior of natural and social phenomena". By modelling such interactions, it can suggest that properties exist in the system that had not been noticed in the real world situation. An example field of study is how unintended consequences arise in social processes.<br />
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生成科学是探索自然世界及其复杂行为的研究领域。它探索了“基于再现或类似自然和社会现象行为的确定性和有限性规则和参数,产生明显出乎意料和无限的行为”的方法。通过对这种相互作用进行建模,它可以表明系统中存在着在现实世界中没有注意到的特性。研究领域的一个例子是研究社会过程中如何产生出乎意料的结果。 <br />
<br />
<br />
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Generative sciences often explore natural phenomena at several levels of organization.<ref>{{Cite journal | last1 = Farre | first1 = G. L. | title = The Energetic Structure of Observation: A Philosophical Disquisition | doi = 10.1177/0002764297040006004 | journal = American Behavioral Scientist | volume = 40 | issue = 6 | pages = 717–728 | year = 1997 | pmid = | pmc = }}</ref><ref name= "Schmidhuber">J. Schmidhuber. (1997) [https://arxiv.org/abs/quant-ph/9904050 A computer scientist's view of life, the universe, and everything]. Foundations of Computer Science: Potential – Theory – Cognition, Lecture Notes in Computer Science, pages 201–208, Springer</ref> [[Self-organization|Self-organizing]] natural systems are a central subject, studied both theoretically and by simulation experiments. The study of complex systems in general has been grouped under the heading of "[[general systems theory]]", particularly by [[Ludwig von Bertalanffy]], [[Anatol Rapoport]], [[Ralph Gerard]], and [[Kenneth Boulding]].<br />
<br />
Generative sciences often explore natural phenomena at several levels of organization. Self-organizing natural systems are a central subject, studied both theoretically and by simulation experiments. The study of complex systems in general has been grouped under the heading of "general systems theory", particularly by Ludwig von Bertalanffy, Anatol Rapoport, Ralph Gerard, and Kenneth Boulding.<br />
<br />
生成科学经常在组织的几个层次上探索自然现象。自组织自然系统是一个重要的研究课题,无论是理论研究还是仿真实验都是如此。一般来说,复杂系统的研究被归在“一般系统理论”的课题下,代表人物有路德维希·冯·贝尔塔兰菲、阿纳托尔·拉波波特、拉尔夫·杰拉德和肯尼斯·博尔丁。<br />
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These sciences include [[psychology]] and [[cognitive science]], [[cellular automata]], [[generative linguistics]], [[natural language processing]], [[connectionism]], [[self-organization]], [[evolutionary biology]], [[neural network]], [[social network]], [[Cognitive musicology|neuromusicology]], [[quantum cellular automata]], [[information theory]], [[systems theory]], [[genetic algorithm]]s, [[computational sociology]], [[Telecommunications network|communication networks]], [[artificial life]], [[chaos theory]], [[Complex systems|complexity theory]], [[network science]], [[epistemology]], [[quantum dot cellular automaton]], [[quantum computer]], [[systems thinking]], [[genetics]], [[economy]], [[philosophy of science]], [[quantum mechanics]], [[cybernetics]], [[digital physics]], [[digital philosophy]], [[bioinformatics]], [[agent-based model]]ing and [[catastrophe theory]].<br />
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These sciences include psychology and cognitive science, cellular automata, generative linguistics, natural language processing, connectionism, self-organization, evolutionary biology, neural network, social network, neuromusicology, quantum cellular automata, information theory, systems theory, genetic algorithms, computational sociology, communication networks, artificial life, chaos theory, complexity theory, network science, epistemology, quantum dot cellular automaton, quantum computer, systems thinking, genetics, economy, philosophy of science, quantum mechanics, cybernetics, digital physics, digital philosophy, bioinformatics, agent-based modeling and catastrophe theory.<br />
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这些科学包括心理学和认知科学、细胞自动机、生成语言学、自然语言处理、连接主义、自我组织、进化生物学、神经网络、社会网络、神经音乐学、量子细胞自动机、信息论、系统论、遗传算法、计算社会学、通信网络、人工生命、混沌理论、复杂性理论、网络科学、认识论、量子点细胞自动机、量子计算机、系统思维、遗传学、经济学、科学哲学、量子力学、控制论、数字物理学、数字哲学、生物信息学、基于代理的建模和灾难理论。<br />
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==Scientific and philosophical origins科学哲学渊源==<br />
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[[File:Airplane vortex edit.jpg|thumb|[[Turbulence]] in the [[Wingtip vortices|tip vortex]] from an [[airplane]] wing. Studies of the critical point beyond which a system creates turbulence were important for [[chaos theory]], analyzed for example by the [[Soviet physicists|Soviet physicist]] [[Lev Landau]] who developed the [[Landau-Hopf theory of turbulence]]. [[David Ruelle]] and [[Floris Takens]] later predicted, against Landau, that [[fluid turbulence]] could develop through a [[strange attractor]], a main concept of chaos theory.]]<br />
<br />
[[Turbulence in the tip vortex from an airplane wing. Studies of the critical point beyond which a system creates turbulence were important for chaos theory, analyzed for example by the Soviet physicist Lev Landau who developed the Landau-Hopf theory of turbulence. David Ruelle and Floris Takens later predicted, against Landau, that fluid turbulence could develop through a strange attractor, a main concept of chaos theory.]]<br />
<br />
飞机机翼顶端涡流中的湍流。关于系统产生湍流的临界点的研究对于混沌理论非常重要,例如,苏联物理学家Lev Landau开发了Landau-Hopf湍流理论。大卫·鲁埃尔和弗洛里斯·塔肯斯后来预言,流体湍流可能通过一个奇怪的吸引子发展,而这个吸引子是混沌理论的主要概念。 <br />
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[[File:Forest of synthetic pyramidal dendrites grown using Cajal's laws of neuronal branching.png|thumb|200px|[[Computer simulation]] of the branching architecture of the [[dendrite]]s of [[pyramidal neuron]]s.<ref>{{Cite journal |author=Hermann Cuntz | doi = 10.1371/image.pcbi.v06.i08 | title = PLoS Computational Biology Issue Image &#124; Vol. 6(8) August 2010 | journal = PLOS Computational Biology | volume = 6 | issue = 8 | pages = ev06.ei08 | year = 2010 | pmid = | pmc = | doi-access = free }}</ref>]]<br />
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[[Computer simulation of the branching architecture of the dendrites of pyramidal neurons.]]<br />
<br />
[大锥体神经元树突分支结构的计算机模拟]<br />
<br />
[[File:Auklet flock Shumagins 1986.jpg|right|200px|thumb|The natural phenomenon of herd behaviour as in a flock of birds can be modelled artificially using simple rules in individual units, with [[swarm intelligence]] rather than any centralized control.]]<br />
<br />
The natural phenomenon of herd behaviour as in a flock of birds can be modelled artificially using simple rules in individual units, with [[swarm intelligence rather than any centralized control.]]<br />
<br />
群体行为的自然现象,如鸟群中的行为,可以用简单的个体规则,用群体智能而不是任何集中控制来人工模拟。<br />
<br />
<br />
The development of computers and [[automata theory]] laid a technical foundation for the growth of the generative sciences. For example:<br />
<br />
The development of computers and automata theory laid a technical foundation for the growth of the generative sciences. For example:<br />
<br />
计算机和自动机理论的发展为生殖科学的发展奠定了技术基础。例如:<br />
<br />
*[[Cellular automaton|Cellular automata]] are mathematical representations of simple entities interacting under [[determinism|deterministic]] rules to manifest complex behaviours. They can be used to model emergent processes of the physical universe, neural cognitive processes and social behavior.<ref name="Kenrick">{{cite journal | doi = 10.1037/0033-295X.110.1.3 | last1 = Kenrick | first1 = DT | last2 = Li | first2 = NP | last3 = Butner | first3 = J | title = Dynamical evolutionary psychology: individual decision rules and emergent social norms | journal = Psychological Review | volume = 110 | issue = 1 | pages = 3–28 | year = 2003 | pmid = 12529056 | citeseerx = 10.1.1.526.5218 }}</ref><ref name="EpsteinAxtell">{{cite book|first1=Joshua M.|last1=Epstein|authorlink1=Joshua M. Epstein|first2=Robert L.|last2=Axtell|authorlink2=Robert Axtell|year=1996|title=Growing Artificial Societies: Social Science From the Bottom Up|publisher=MIT/Brookings Institution|location=Cambridge MA|page=[https://archive.org/details/growingartificia00epst/page/224 224]|isbn=978-0-262-55025-3|url-access=registration|url=https://archive.org/details/growingartificia00epst/page/224}}</ref><ref name= "Nowak">{{citation |authors=Nowak A., Vallacher R.R., Tesser A., Borkowski W. |year=2000 |title=Society of Self: The emergence of collective properties in self-structure |journal=Psychological Review |volume=107 |issue=1 |pages=39–61 |pmid=10687402 |doi=10.1037/0033-295x.107.1.39}}</ref><ref name= "Epstein">{{citation |author=Epstein J.M. |year=1999 |title=Agent Based Computational Models and Generative Social Science |journal=Complexity |volume=4 |issue=5 |pages=41–60 |doi=10.1002/(SICI)1099-0526(199905/06)4:5<41::AID-CPLX9>3.0.CO;2-F|bibcode=1999Cmplx...4e..41E |citeseerx=10.1.1.353.5950 }}</ref><br />
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**[[Conway's Game of Life]] is a zero-player game based on cellular automata, meaning that the only input is in setting the initial conditions, and the game is to see how the system evolves.<ref>[http://www.bitstorm.org/gameoflife/ John Conway's Game of Life]</ref><br />
[Conway's Game of Life]]是一款基于元胞自动机的零人游戏,也就是说,唯一的输入是设置初始条件,游戏就是看系统如何进化 <br />
**In 1996 [[Joshua M. Epstein]] and [[Robert Axtell]] wrote the book ''Growing Artificial Societies'' which proposes a set of automaton rules and a system called ''[[Sugarscape]]'' which models a population dependent on resources (called sugar).<br />
1996年,[[约书亚M爱泼斯坦]]和[[罗伯特·阿克斯泰尔]]写了一本书《成长中的人工社会》,书中提出了一套自动化规则和一个名为“[[Sugarscape]]”的系统,该系统对依赖资源的人口(称为sugar)进行建模 <br />
*[[Artificial neural network]]s attempt to solve problems in the same way that the human brain would, although they are still several orders of magnitude less complex than the human brain and closer to the computing power of a worm. Advances in the understanding of the human brain often stimulate new patterns in neural networks.<br />
[[人工神经网络]]试图以人脑同样的方式解决问题,尽管它们的复杂程度仍比人脑低几个数量级,更接近蠕虫的计算能力。对人脑的理解的进步经常刺激神经网络的新模式。 <br />
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One of the most influential advances in the generative sciences as related to [[cognitive science]] came from [[Noam Chomsky]]'s (1957) development of [[generative grammar]], which separated language generation from semantic content, and thereby revealed important questions about human language. It was also in the early 1950s that psychologists at the MIT including [[Kurt Lewin]], [[Jacob Levy Moreno]] and [[Fritz Heider]] laid the foundations for [[group dynamics]] research which later developed into [[social network]] analysis.<br />
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One of the most influential advances in the generative sciences as related to cognitive science came from Noam Chomsky's (1957) development of generative grammar, which separated language generation from semantic content, and thereby revealed important questions about human language. It was also in the early 1950s that psychologists at the MIT including Kurt Lewin, Jacob Levy Moreno and Fritz Heider laid the foundations for group dynamics research which later developed into social network analysis.<br />
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与认知科学相关的生成科学中最具影响力的进展之一来自诺姆·乔斯基(1957)对生成语法的发展,它将语言生成与语义内容分离开来,从而揭示了有关人类语言的重要问题。同样是在20世纪50年代早期,麻省理工学院的心理学家库尔特·勒温、雅各布·利维·莫雷诺和弗里茨·海德为后来发展为社会网络分析的群体动力学研究奠定了基础。 <br />
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== See also参见 ==<br />
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* {{annotated link|Generative systems}}<br />
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生成系统<br />
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==References参考==<br />
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{{Reflist|30em}}<br />
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==External links外部链接==<br />
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* http://www.swarthmore.edu/socsci/tburke1/artsoc.html (Artificial Societies, Virtual Worlds and the Shared Problems and Possibilities of Emergence)<br />
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* http://jasss.soc.surrey.ac.uk/JASSS.html (The Journal of Artificial Societies and Social Simulation)<br />
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[[Category:Systems theory]]<br />
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Category:Systems theory<br />
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范畴: 系统论<br />
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<small>This page was moved from [[wikipedia:en:Generative science]]. Its edit history can be viewed at [[生成科学/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%9C%89%E5%99%AA%E4%BF%A1%E9%81%93%E7%BC%96%E7%A0%81%E5%AE%9A%E7%90%86&diff=20916有噪信道编码定理2021-01-15T09:11:14Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Limit on data transfer rate}}<br />
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{{Information theory}}<br />
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{{redirect|Shannon's theorem|text=Shannon's name is also associated with the [[sampling theorem]]}}<br />
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In [[information theory]], the '''noisy-channel coding theorem''' (sometimes '''Shannon's theorem''' or '''Shannon's limit'''), establishes that for any given degree of [[Noisy channel model|noise contamination of a communication channel]], it is possible to communicate discrete data (digital [[information]]) nearly error-free up to a computable maximum rate through the channel. This result was presented by [[Claude Shannon]] in 1948 and was based in part on earlier work and ideas of [[Harry Nyquist]] and [[Ralph Hartley]].<br />
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In information theory, the noisy-channel coding theorem (sometimes Shannon's theorem or Shannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible to communicate discrete data (digital information) nearly error-free up to a computable maximum rate through the channel. This result was presented by Claude Shannon in 1948 and was based in part on earlier work and ideas of Harry Nyquist and Ralph Hartley.<br />
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在信息论中,<font color="#ff8000">Noisy-channel coding theorem有噪声信道编码定理</font>(有时是香农定理或香农极限)确定了对于通信信道的任何给定程度的噪声污染,都有可能通过信道传输几乎无差错的离散数据(数字信息),从而达到可计算的最大速率。这个结果是由克劳德·香农在1948年提出的,部分基于哈利·奈奎斯特和拉尔夫·哈特利早期的工作和思想。<br />
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The '''Shannon limit''' or '''Shannon capacity''' of a communication channel refers to the maximum [[Code rate|rate]] of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by [[Claude E. Shannon|Claude Elwood Shannon]] and [[Warren Weaver]] in [[1949]] entitled ''The Mathematical Theory of Communication.'' ({{ISBN|0252725484}}). This founded the modern discipline of [[information theory]]. <br />
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The Shannon limit or Shannon capacity of a communication channel refers to the maximum rate of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by Claude Elwood Shannon and Warren Weaver in 1949 entitled The Mathematical Theory of Communication. (). This founded the modern discipline of information theory. <br />
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通信信道的香农极限或香农容量是指在特定噪声水平下,如果链路受到随机数据传输错误的影响,理论上可以通过信道传输的最大无错误数据速率。它最早由香农(1948)描述,不久后在1949年由克劳德·埃尔伍德·香农和沃伦·韦弗出版的一本书中发表,书名为《通信的数学理论》。这奠定了现代信息论学科的基础。 <br />
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== Overview 总览==<br />
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Stated by [[Claude Shannon]] in 1948, the theorem describes the maximum possible efficiency of [[error-correcting code|error-correcting methods]] versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and [[data storage device|data storage]]. This theorem is of foundational importance to the modern field of [[information theory]]. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to [[Amiel Feinstein]]<ref>{{Cite journal|date=1954|others=Feinstein, Amiel.|title=A new basic theorem of information theory|hdl=1721.1/4798|bibcode=1955PhDT........12F}}</ref> in 1954.<br />
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Stated by Claude Shannon in 1948, the theorem describes the maximum possible efficiency of error-correcting methods versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and data storage. This theorem is of foundational importance to the modern field of information theory. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to Amiel Feinstein in 1954.<br />
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香农在1948年提出的定理描述了纠错方法的最大可能效率与噪声干扰和数据损坏程度的关系。香农定理在通信和数据存储中都有广泛的应用。这个定理对现代信息论领域具有重要的基础性意义。香农只概述了证明。1954年,阿米尔·范斯坦提出了离散情况的第一个严格证明。<br />
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The Shannon theorem states that given a noisy channel with [[channel capacity]] ''C'' and information transmitted at a rate ''R'', then if <math>R < C</math> there exist [[code]]s that allow the [[probability of error]] at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, ''C''.<br />
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The Shannon theorem states that given a noisy channel with channel capacity C and information transmitted at a rate R, then if <math>R < C</math> there exist codes that allow the probability of error at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, C.<br />
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香农定理指出,给定一个信道容量为C的噪声信道和以R速率传输的信息,那么如果R<C,则存在允许接收机处的错误概率任意小的码。这意味着,从理论上讲,以低于极限速率C的任何速率几乎无误地传输信息是可能的。<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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定理反过来也很重要。如果R>C,任意小的错误概率都是不可能实现的。所有代码的错误概率都将大于某个正最小水平,并且该水平随着速率的增加而增加。因此,不能保证信息以超出信道容量的速率可靠地跨信道传输。这个定理并不适用于速率和容量相等的罕见情况<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the [[Shannon–Hartley theorem]].<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the Shannon–Hartley theorem.<br />
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信道容量C可以从信道的物理特性计算出来,对于带有高斯噪声的带限信道,可以使用<font color="#ff8000"> Shannon–Hartley theorem香农-哈特莱定理</font>。<br />
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Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as [[Reed–Solomon code]]s and, more recently, [[low-density parity-check code|low-density parity-check]] (LDPC) codes and [[turbo code]]s, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's [[digital signal processors]], it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary [[Additive white Gaussian noise]] (AWGN) channels, with very long block lengths).<ref>[[Sae-Young Chung]], [[G. David Forney, Jr.]], [[Thomas J. Richardson]], and [[Rüdiger Urbanke]], "[http://www.josephboutros.org/ldpc_vs_turbo/ldpc_Chung_CLfeb01.pdf On the Design of Low-Density Parity-Check Codes within 0.0045 dB of the Shannon Limit]", ''[[IEEE Communications Letters]]'', 5: 58-60, Feb. 2001. ISSN 1089-7798</ref><br />
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Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as Reed–Solomon codes and, more recently, low-density parity-check (LDPC) codes and turbo codes, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's digital signal processors, it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary Additive white Gaussian noise (AWGN) channels, with very long block lengths).<br />
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诸如“发送消息3次,如果副本不同,则使用3选2最佳投票方案”之类的简单方案是低效的纠错方法,无法渐近地保证数据块可以无错误地通信。诸如Reed-Solomon码以及最近的低密度奇偶校验(LDPC)码和turbo码之类的先进技术更接近于达到理论上的香农极限,但代价是计算复杂度很高。使用这些高效的代码和当今数字信号处理器的计算能力,现在有可能达到非常接近香农极限。事实上,LDPC码可以达到香农极限的0.0045dB以内(对于二进制加性高斯白噪声(AWGN)信道,具有很长的块长度)。 。<br />
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== Mathematical statement数学表述 ==<br />
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The basic mathematical model for a communication system is the following:<br />
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The basic mathematical model for a communication system is the following:<br />
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通信系统的基本数学模型如下:<br />
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[[File:Channel model.svg|center|800px|Channel model]]<br />
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Channel model<br />
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通道模型<br />
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A '''message''' ''W'' is transmitted through a noisy channel by using encoding and decoding functions. An '''encoder''' maps ''W'' into a pre-defined sequence of channel symbols of length ''n''. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a '''decoder''' which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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A message W is transmitted through a noisy channel by using encoding and decoding functions. An encoder maps W into a pre-defined sequence of channel symbols of length n. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a decoder which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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通过使用编码和解码功能,通过噪声信道传送消息W。编码器将W映射到长度为n的预定义信道符号序列中。在其最基本的模型中,信道独立于其他符号而扭曲这些符号中的每一个。信道的输出——接收到的序列——被送入解码器,解码器将序列映射成消息的估计。在此设置中,错误概率定义为:<br />
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::<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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[数学 > p _ e = 文本{ Pr }左{ w } neq w 右}。数学<br />
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'''Theorem''' (Shannon, 1948):<br />
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Theorem (Shannon, 1948):<br />
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定理(Shannon,1948) :<br />
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:1. For every discrete memoryless channel, the [[channel capacity]] is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1. For every discrete memoryless channel, the channel capacity is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1.对于每一个离散的无记忆信道,信道容量是根据互信息I(x; y)来定义的,<br />
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::<math>\ C = \sup_{p_X} I(X;Y)</math><ref>For a description of the "sup" function, see [[Supremum]]</ref><br />
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<math>\ C = \sup_{p_X} I(X;Y)</math><br />
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[ math > c = sup { p _ x } i (x; y) </math ]<br />
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:has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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具有以下属性。对于任何ε>0 和 R<C ,对于足够大的N ,存在一个长度为 N 和速率R的代码和一个解码算法,使得块错误的最大概率为ε 。<br />
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:2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2.如果位错概率pb是可以接受的,那么达到R(pb)的速率是可以实现的<br />
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::<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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1-H _ 2(p _ b)} . </math > <br />
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:and <math> H_2(p_b)</math> is the ''[[binary entropy function]]''<br />
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and <math> H_2(p_b)</math> is the binary entropy function<br />
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2(p _ b) </math > 是二元熵函数<br />
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::<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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< math > h _ 2(p _ b) =-左[ p _ b log_2{ p _ b } + (1-p _ b) log_2({1-p _ b })右] </math > <br />
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:3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3.对于任何pb ,比率大于R(pb)是无法实现的。<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003) ,第162页; cf Gallager (1968) ,第5章; Cover and Thomas (1991) ,第198页; Shannon (1948) thm。11)<br />
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== Outline of proof证明概述 ==<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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结合信息论中的其他几个主要结果,噪声信道编码定理的证明包括一个可达性结果和一个匹配逆结果。在这种情况下,这两个分量用来限定一个人在噪声信道上进行通信的可能速率集,而匹配用来表明这些界限是紧界限。<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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下面的提纲只是信息论文本中可供学习的许多不同风格中的一组 <br />
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===Achievability for discrete memoryless channels离散无记忆信道的可达性===<br />
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This particular proof of achievability follows the style of proofs that make use of the [[asymptotic equipartition property]] (AEP). Another style can be found in information theory texts using [[error exponent]]s.<br />
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This particular proof of achievability follows the style of proofs that make use of the asymptotic equipartition property (AEP). Another style can be found in information theory texts using error exponents.<br />
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这个特殊的可实现性证明遵循了利用渐近均分性质(AEP)的证明风格。另一种风格可以在信息论文本中找到使用错误指数。 <br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the [[channel capacity]].<br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the channel capacity.<br />
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这两种类型的证明都使用了一个随机编码参数,其中跨信道使用的码本是随机构造的-这使得分析更简单,同时仍然证明在低于信道容量的任何数据速率下,存在满足期望的低错误概率的码。 <br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a ''jointly typical set'' by the following:<br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a jointly typical set by the following:<br />
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通过一个与 aep-相关的参数,给定一个通道,长度n的源符号的字符串X1n,以及长度n通道输出的字符串Y1n,我们可以定义一个联合的典型集合如下:<br />
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: <math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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<math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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:::<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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2 ^ {-n (h (x) + varepsilon)} le p (x _ 1 ^ n) le 2 ^ {-n (h (x)-varepsilon)} </math > <br />
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:::<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
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<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
<br />
2 ^ {-n (h (y) + varepsilon)} le p (y _ 1 ^ n) le 2 ^ {-n (h (y)-varepsilon)}<br />
<br />
<br />
<br />
:::<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
<br />
<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
<br />
{2 ^ {-n (h (x,y) + varepsilon)} le p (x _ 1 ^ n,y _ 1 ^ n) le 2 ^ {-n (h (x,y)-varepsilon)}<br />
<br />
<br />
<br />
We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are ''jointly typical'' if they lie in the jointly typical set defined above.<br />
<br />
We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are jointly typical if they lie in the jointly typical set defined above.<br />
<br />
我们说两个序列X1n和Y1n如果它们位于上面定义的联合典型集合中,那么它们是共同典型的。<br />
<br />
<br />
<br />
'''Steps'''<br />
<br />
Steps<br />
<br />
步骤<br />
<br />
#In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
<br />
In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
<br />
在随机编码参数的风格中,我们随机从概率分布 q 生成长度为 n 的长度为2nR的码字。<br />
<br />
#This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
<br />
This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
<br />
这段代码向发送者和接收者显示。还假设人们知道所使用的通道的转移矩阵。<br />
<br />
#A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
<br />
A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
<br />
根据码字集上的均匀分布选择消息 w。也就是,Pr (w = w) = 2-nR ,w = 1,2,,2nR。<br />
<br />
#The message W is sent across the channel.<br />
<br />
The message W is sent across the channel.<br />
<br />
消息 w 是通过通道发送的。<br />
<br />
#The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
<br />
The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
<br />
接收端根据P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))接收一个序列<br />
<br />
#Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called ''typical set decoding''.<br />
<br />
Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called typical set decoding.<br />
<br />
通过信道发送这些码字,我们接收到Y1n,并解码到某个源序列,如果存在正好与 y 共同典型的一个码字。如果没有共同的典型代码字,或者有多个代码字,则声明错误。如果解码的码字与原始码字不匹配,也会发生错误。这就是所谓的典型集合译码。<br />
<br />
<br />
<br />
The probability of error of this scheme is divided into two parts:<br />
<br />
The probability of error of this scheme is divided into two parts:<br />
<br />
该方案的误差概率分为两部分:<br />
<br />
<br />
<br />
#First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
<br />
First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
<br />
首先,如果没有为接收到的 y 序列找到联合的典型 x 序列,就可能发生错误<br />
<br />
#Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
<br />
Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
<br />
其次,如果一个不正确的 x 序列与一个接收到的 y 序列是共同的典型,则可能发生错误。<br />
<br />
<br />
<br />
*By the randomness of the code construction, we can assume that the average probability of error averaged over all codes does not depend on the index sent. Thus, without loss of generality, we can assume ''W'' = 1.<br />
<br />
*From the joint AEP, we know that the probability that no jointly typical X exists goes to 0 as n grows large. We can bound this error probability by <math>\varepsilon</math>.<br />
<br />
*Also from the joint AEP, we know the probability that a particular <math>X_1^{n}(i)</math> and the <math>Y_1^n</math> resulting from ''W'' = 1 are jointly typical is <math>\le 2^{-n(I(X;Y) - 3\varepsilon)}</math>.<br />
<br />
<br />
<br />
Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
<br />
Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
<br />
<br />
<br />
<br />
as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
<br />
as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
<br />
作为消息 i 与消息1发送时接收到的序列一起发生的典型事件。<br />
<br />
<br />
<br />
: <math><br />
<br />
<math><br />
<br />
《数学》<br />
<br />
\begin{align}<br />
<br />
\begin{align}<br />
<br />
开始{ align }<br />
<br />
P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
<br />
P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
<br />
P (text { error }) & {} = p (text { error } | w = 1) le p (e_1 ^ c) + sum _ { i = 2} ^ {2 ^ { nR }} p (e_i)<br />
<br />
& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
<br />
& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
<br />
& {} le p (e _ 1 ^ c) + (2 ^ { nR }-1)2 ^ {-n (i (x; y)-3 varepsilon)}<br />
<br />
& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
<br />
& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
<br />
& {} le varepsilon + 2 ^ {-n (i (x; y)-R-3 varepsilon)}.<br />
<br />
\end{align}<br />
<br />
\end{align}<br />
<br />
结束{ align }<br />
<br />
</math><br />
<br />
</math><br />
<br />
数学<br />
<br />
<br />
<br />
We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
<br />
We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
<br />
我们可以观察到,当n趋于无穷大时,如果R<I(X;Y)对于通道,错误概率将趋于0。<br />
<br />
<br />
<br />
Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
<br />
Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
<br />
最后,假设平均码本是“好的” ,我们知道存在一个性能优于平均值的码本,从而满足了我们在噪声信道中任意低错误概率通信的需要。<br />
<br />
<br />
<br />
=== Weak converse for discrete memoryless channels离散无记忆信道的弱逆===<br />
<br />
<br />
<br />
Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
<br />
Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
<br />
假设一个2nR代码字的代码。让 w 作为索引均匀地绘制在这个集合上。让 x ^ n和 y ^ n 分别作为传输代码和接收代码。<br />
<br />
<br />
<br />
#<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and [[mutual information]]<br />
<br />
<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and mutual information<br />
<br />
使用包含熵和互信息的恒等式nR=H(W)=H(W|Yn)+I(W;Yn)<br />
<br />
#<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
<br />
<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
<br />
因为 x 是 w 的一个函数,所以它是一个数学公式<br />
<br />
#<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of [[Fano's Inequality]]<br />
<br />
<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of Fano's Inequality<br />
<br />
利用 Fano 不等式,得到了一个新的数学公式≤1+Pe(n)nR+I(Xn(W);Yn)<br />
<br />
#<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
<br />
<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
<br />
由于容量是最大化的互信息,因此≤1+Pe(n)nR+nC。<br />
<br />
<br />
<br />
The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
<br />
The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
<br />
这些步骤的结果是Pe(n)≥1−1nR−CR。当块长度n 趋于无穷大时,我们得到当R大于C时Pe(n)远离0,我们只有当R小于C时才能得到任意低的误差率。<br />
<br />
<br />
<br />
=== Strong converse for discrete memoryless channels离散无记忆信道的强逆 ===<br />
<br />
<br />
<br />
A strong converse theorem, proven by Wolfowitz in 1957,<ref>Robert Gallager. ''Information Theory and Reliable Communication.'' New York: [[John Wiley & Sons]], 1968. {{ISBN|0-471-29048-3}}</ref> states that,<br />
<br />
A strong converse theorem, proven by Wolfowitz in 1957, states that,<br />
<br />
沃尔福威茨在1957年证明了一个强逆定理,<br />
<br />
<br />
<br />
:<math><br />
<br />
<math><br />
<br />
《数学》<br />
<br />
P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
<br />
P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
<br />
P _ e geq 1-frac {4A }{ n (R-C) ^ 2}-e ^ {-frac { n (R-C)}{2}<br />
<br />
</math><br />
<br />
</math><br />
<br />
数学<br />
<br />
<br />
<br />
for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
<br />
for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
<br />
为了某个有限的正常数。当弱逆表示错误概率远离零是有界的时候,强逆表示错误概率远离零是有界的。因此,C是完全可靠和完全不可靠的通信之间的一个尖锐的门槛。<br />
<br />
<br />
<br />
== Channel coding theorem for non-stationary memoryless channels==<br />
<br />
We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
<br />
We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
<br />
我们假设信道是无记忆的,但是它的跃迁概率随时间而变化,这种变化在发射机和接收机中都是已知的。<br />
<br />
<br />
<br />
Then the channel capacity is given by<br />
<br />
Then the channel capacity is given by<br />
<br />
然后通过对信道容量的分析,给出信道容量的计算公式<br />
<br />
<br />
<br />
:<math> <br />
<br />
<math> <br />
<br />
《数学》<br />
<br />
C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
<br />
C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
<br />
C = lim inf max { p ^ {(x _ 1)} ,p ^ {(x _ 2)} ,... } frac {1}{ n } sum { i = 1} ^ nI (x _ i; y _ i).<br />
<br />
</math><br />
<br />
</math><br />
<br />
数学<br />
<br />
<br />
<br />
The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
<br />
The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
<br />
在每个通道的容量分配上达到最大值。就是,<br />
<br />
<math><br />
<br />
<math><br />
<br />
《数学》<br />
<br />
C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
<br />
C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
<br />
1}{ n } sum { i = 1} ^ n c _ i<br />
<br />
</math><br />
<br />
</math><br />
<br />
数学<br />
<br />
where <math>C_i</math> is the capacity of the i''th'' channel.<br />
<br />
where <math>C_i</math> is the capacity of the ith channel.<br />
<br />
其中Ci是第i通道的容量。<br />
<br />
<br />
<br />
=== Outline of the proof证明概述===<br />
<br />
The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the [[asymptotic equipartition property]] article.<br />
<br />
The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the asymptotic equipartition property article.<br />
<br />
该证明与信道编码定理的证明几乎相同。可实现性来自随机编码,每个符号从该特定信道的容量实现分布中随机选择。典型性参数使用渐近均分性质文章中定义的非平稳源的典型集的定义<br />
<br />
<br />
<br />
The technicality of [[lim inf]] comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
<br />
The technicality of lim inf comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
<br />
当 1n∑i=1nCi不收敛时,lim inf 的技术性就发挥了作用。<br />
<br />
<br />
<br />
==See also参见==<br />
<br />
* [[Asymptotic equipartition property]] (AEP)<br />
渐近均分性 <br />
* [[Fano's inequality]]<br />
法诺不等式<br />
* [[Rate–distortion theory]]<br />
率失真理论<br />
* [[Shannon's source coding theorem]]<br />
香农信源编码定理<br />
* [[Shannon–Hartley theorem]]<br />
香农-哈特莱定理 <br />
* [[Turbo code]]<br />
涡轮码<br />
<br />
<br />
==Notes批注==<br />
<br />
{{reflist}}<br />
<br />
<br />
<br />
==References参考==<br />
<br />
* [[Thomas M. Cover|Cover T. M.]], Thomas J. A., ''Elements of Information Theory'', [[John Wiley & Sons]], 1991. {{ISBN|0-471-06259-6}}<br />
<br />
*[[Fano|Fano, R. A.]], ''Transmission of information; a statistical theory of communications'', [[MIT Press]], 1961. {{ISBN|0-262-06001-9}}<br />
<br />
*[[Amiel Feinstein|Feinstein, Amiel]], "A New basic theorem of information theory", ''[[IEEE Transactions on Information Theory]]'', 4(4): 2-22, 1954.<br />
<br />
* [[David J.C. MacKay|MacKay, David J. C.]], ''[http://www.inference.phy.cam.ac.uk/mackay/itila/book.html Information Theory, Inference, and Learning Algorithms]'', [[Cambridge University Press]], 2003. {{ISBN|0-521-64298-1}} [free online]<br />
<br />
*[[Claude E. Shannon|Shannon, C. E.]], [https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6773024 ''A Mathematical Theory of Communication'']. ''The Bell System Technical Journal'' 27,3: 379–423, 1948.<br />
<br />
*[[Claude E. Shannon|Shannon, C. E.]], [http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html ''A Mathematical Theory of Communication''] Urbana, IL: University of Illinois Press, 1948 (reprinted 1998).<br />
<br />
*[[Wolfowitz| Wolfowitz, J.]], "[https://projecteuclid.org/download/pdf_1/euclid.ijm/1255380682 The coding of messages subject to chance errors]", ''Illinois J. Math.'', 1: 591–606, 1957.<br />
<br />
<br />
<br />
==External links外部链接==<br />
<br />
* [http://www.cs.miami.edu/home/burt/learning/Csc524.142/LarsTelektronikk02.pdf On Shannon and Shannon's law]<br />
<br />
* [http://cnx.org/content/m10180/latest/ Shannon's Noisy Channel Coding Theorem]<br />
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<br />
<br />
{{DEFAULTSORT:Noisy-Channel Coding Theorem}}<br />
<br />
[[Category:Information theory]]<br />
<br />
Category:Information theory<br />
<br />
范畴: 信息论<br />
<br />
[[Category:Theorems in discrete mathematics]]<br />
<br />
Category:Theorems in discrete mathematics<br />
<br />
范畴: 离散数学的定理<br />
<br />
[[Category:Telecommunication theory]]<br />
<br />
Category:Telecommunication theory<br />
<br />
范畴: 电信理论<br />
<br />
[[Category:Coding theory]]<br />
<br />
Category:Coding theory<br />
<br />
类别: 编码理论<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Noisy-channel coding theorem]]. Its edit history can be viewed at [[有噪信道编码定理/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%9C%89%E5%99%AA%E4%BF%A1%E9%81%93%E7%BC%96%E7%A0%81%E5%AE%9A%E7%90%86&diff=20915有噪信道编码定理2021-01-15T09:09:32Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译。<br />
<br />
{{short description|Limit on data transfer rate}}<br />
<br />
{{Information theory}}<br />
<br />
{{redirect|Shannon's theorem|text=Shannon's name is also associated with the [[sampling theorem]]}}<br />
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<br />
<br />
In [[information theory]], the '''noisy-channel coding theorem''' (sometimes '''Shannon's theorem''' or '''Shannon's limit'''), establishes that for any given degree of [[Noisy channel model|noise contamination of a communication channel]], it is possible to communicate discrete data (digital [[information]]) nearly error-free up to a computable maximum rate through the channel. This result was presented by [[Claude Shannon]] in 1948 and was based in part on earlier work and ideas of [[Harry Nyquist]] and [[Ralph Hartley]].<br />
<br />
In information theory, the noisy-channel coding theorem (sometimes Shannon's theorem or Shannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible to communicate discrete data (digital information) nearly error-free up to a computable maximum rate through the channel. This result was presented by Claude Shannon in 1948 and was based in part on earlier work and ideas of Harry Nyquist and Ralph Hartley.<br />
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在信息论中,有噪声信道编码定理(有时是香农定理或香农极限)确定了对于通信信道的任何给定程度的噪声污染,都有可能通过信道传输几乎无差错的离散数据(数字信息),从而达到可计算的最大速率。这个结果是由克劳德·香农在1948年提出的,部分基于哈利·奈奎斯特和拉尔夫·哈特利早期的工作和思想。<br />
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The '''Shannon limit''' or '''Shannon capacity''' of a communication channel refers to the maximum [[Code rate|rate]] of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by [[Claude E. Shannon|Claude Elwood Shannon]] and [[Warren Weaver]] in [[1949]] entitled ''The Mathematical Theory of Communication.'' ({{ISBN|0252725484}}). This founded the modern discipline of [[information theory]]. <br />
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The Shannon limit or Shannon capacity of a communication channel refers to the maximum rate of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by Claude Elwood Shannon and Warren Weaver in 1949 entitled The Mathematical Theory of Communication. (). This founded the modern discipline of information theory. <br />
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通信信道的香农极限或香农容量是指在特定噪声水平下,如果链路受到随机数据传输错误的影响,理论上可以通过信道传输的最大无错误数据速率。它最早由香农(1948)描述,不久后在1949年由克劳德·埃尔伍德·香农和沃伦·韦弗出版的一本书中发表,书名为《通信的数学理论》。这奠定了现代信息论学科的基础。 <br />
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== Overview 总览==<br />
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Stated by [[Claude Shannon]] in 1948, the theorem describes the maximum possible efficiency of [[error-correcting code|error-correcting methods]] versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and [[data storage device|data storage]]. This theorem is of foundational importance to the modern field of [[information theory]]. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to [[Amiel Feinstein]]<ref>{{Cite journal|date=1954|others=Feinstein, Amiel.|title=A new basic theorem of information theory|hdl=1721.1/4798|bibcode=1955PhDT........12F}}</ref> in 1954.<br />
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Stated by Claude Shannon in 1948, the theorem describes the maximum possible efficiency of error-correcting methods versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and data storage. This theorem is of foundational importance to the modern field of information theory. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to Amiel Feinstein in 1954.<br />
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香农在1948年提出的定理描述了纠错方法的最大可能效率与噪声干扰和数据损坏程度的关系。香农定理在通信和数据存储中都有广泛的应用。这个定理对现代信息论领域具有重要的基础性意义。香农只概述了证明。1954年,阿米尔·范斯坦提出了离散情况的第一个严格证明。<br />
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The Shannon theorem states that given a noisy channel with [[channel capacity]] ''C'' and information transmitted at a rate ''R'', then if <math>R < C</math> there exist [[code]]s that allow the [[probability of error]] at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, ''C''.<br />
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The Shannon theorem states that given a noisy channel with channel capacity C and information transmitted at a rate R, then if <math>R < C</math> there exist codes that allow the probability of error at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, C.<br />
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香农定理指出,给定一个信道容量为C的噪声信道和以R速率传输的信息,那么如果R<C,则存在允许接收机处的错误概率任意小的码。这意味着,从理论上讲,以低于极限速率C的任何速率几乎无误地传输信息是可能的。<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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定理反过来也很重要。如果R>C,任意小的错误概率都是不可能实现的。所有代码的错误概率都将大于某个正最小水平,并且该水平随着速率的增加而增加。因此,不能保证信息以超出信道容量的速率可靠地跨信道传输。这个定理并不适用于速率和容量相等的罕见情况<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the [[Shannon–Hartley theorem]].<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the Shannon–Hartley theorem.<br />
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信道容量C可以从信道的物理特性计算出来,对于带有高斯噪声的带限信道,可以使用香农-哈特莱定理。<br />
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Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as [[Reed–Solomon code]]s and, more recently, [[low-density parity-check code|low-density parity-check]] (LDPC) codes and [[turbo code]]s, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's [[digital signal processors]], it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary [[Additive white Gaussian noise]] (AWGN) channels, with very long block lengths).<ref>[[Sae-Young Chung]], [[G. David Forney, Jr.]], [[Thomas J. Richardson]], and [[Rüdiger Urbanke]], "[http://www.josephboutros.org/ldpc_vs_turbo/ldpc_Chung_CLfeb01.pdf On the Design of Low-Density Parity-Check Codes within 0.0045 dB of the Shannon Limit]", ''[[IEEE Communications Letters]]'', 5: 58-60, Feb. 2001. ISSN 1089-7798</ref><br />
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Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as Reed–Solomon codes and, more recently, low-density parity-check (LDPC) codes and turbo codes, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's digital signal processors, it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary Additive white Gaussian noise (AWGN) channels, with very long block lengths).<br />
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诸如“发送消息3次,如果副本不同,则使用3选2最佳投票方案”之类的简单方案是低效的纠错方法,无法渐近地保证数据块可以无错误地通信。诸如Reed-Solomon码以及最近的低密度奇偶校验(LDPC)码和turbo码之类的先进技术更接近于达到理论上的香农极限,但代价是计算复杂度很高。使用这些高效的代码和当今数字信号处理器的计算能力,现在有可能达到非常接近香农极限。事实上,LDPC码可以达到香农极限的0.0045dB以内(对于二进制加性高斯白噪声(AWGN)信道,具有很长的块长度)。 。<br />
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== Mathematical statement数学表述 ==<br />
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The basic mathematical model for a communication system is the following:<br />
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The basic mathematical model for a communication system is the following:<br />
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通信系统的基本数学模型如下:<br />
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[[File:Channel model.svg|center|800px|Channel model]]<br />
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Channel model<br />
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通道模型<br />
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A '''message''' ''W'' is transmitted through a noisy channel by using encoding and decoding functions. An '''encoder''' maps ''W'' into a pre-defined sequence of channel symbols of length ''n''. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a '''decoder''' which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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A message W is transmitted through a noisy channel by using encoding and decoding functions. An encoder maps W into a pre-defined sequence of channel symbols of length n. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a decoder which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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通过使用编码和解码功能,通过噪声信道传送消息W。编码器将W映射到长度为n的预定义信道符号序列中。在其最基本的模型中,信道独立于其他符号而扭曲这些符号中的每一个。信道的输出——接收到的序列——被送入解码器,解码器将序列映射成消息的估计。在此设置中,错误概率定义为:<br />
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::<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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[数学 > p _ e = 文本{ Pr }左{ w } neq w 右}。数学<br />
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'''Theorem''' (Shannon, 1948):<br />
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Theorem (Shannon, 1948):<br />
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定理(Shannon,1948) :<br />
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:1. For every discrete memoryless channel, the [[channel capacity]] is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1. For every discrete memoryless channel, the channel capacity is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1.对于每一个离散的无记忆信道,信道容量是根据互信息I(x; y)来定义的,<br />
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::<math>\ C = \sup_{p_X} I(X;Y)</math><ref>For a description of the "sup" function, see [[Supremum]]</ref><br />
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<math>\ C = \sup_{p_X} I(X;Y)</math><br />
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[ math > c = sup { p _ x } i (x; y) </math ]<br />
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:has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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具有以下属性。对于任何ε>0 和 R<C ,对于足够大的N ,存在一个长度为 N 和速率R的代码和一个解码算法,使得块错误的最大概率为ε 。<br />
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:2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2.如果位错概率pb是可以接受的,那么达到R(pb)的速率是可以实现的<br />
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::<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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1-H _ 2(p _ b)} . </math > <br />
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:and <math> H_2(p_b)</math> is the ''[[binary entropy function]]''<br />
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and <math> H_2(p_b)</math> is the binary entropy function<br />
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2(p _ b) </math > 是二元熵函数<br />
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::<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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< math > h _ 2(p _ b) =-左[ p _ b log_2{ p _ b } + (1-p _ b) log_2({1-p _ b })右] </math > <br />
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:3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3.对于任何pb ,比率大于R(pb)是无法实现的。<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003) ,第162页; cf Gallager (1968) ,第5章; Cover and Thomas (1991) ,第198页; Shannon (1948) thm。11)<br />
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== Outline of proof证明概述 ==<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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结合信息论中的其他几个主要结果,噪声信道编码定理的证明包括一个可达性结果和一个匹配逆结果。在这种情况下,这两个分量用来限定一个人在噪声信道上进行通信的可能速率集,而匹配用来表明这些界限是紧界限。<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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下面的提纲只是信息论文本中可供学习的许多不同风格中的一组 <br />
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===Achievability for discrete memoryless channels离散无记忆信道的可达性===<br />
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This particular proof of achievability follows the style of proofs that make use of the [[asymptotic equipartition property]] (AEP). Another style can be found in information theory texts using [[error exponent]]s.<br />
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This particular proof of achievability follows the style of proofs that make use of the asymptotic equipartition property (AEP). Another style can be found in information theory texts using error exponents.<br />
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这个特殊的可实现性证明遵循了利用渐近均分性质(AEP)的证明风格。另一种风格可以在信息论文本中找到使用错误指数。 <br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the [[channel capacity]].<br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the channel capacity.<br />
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这两种类型的证明都使用了一个随机编码参数,其中跨信道使用的码本是随机构造的-这使得分析更简单,同时仍然证明在低于信道容量的任何数据速率下,存在满足期望的低错误概率的码。 <br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a ''jointly typical set'' by the following:<br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a jointly typical set by the following:<br />
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通过一个与 aep-相关的参数,给定一个通道,长度n的源符号的字符串X1n,以及长度n通道输出的字符串Y1n,我们可以定义一个联合的典型集合如下:<br />
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: <math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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<math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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:::<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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2 ^ {-n (h (x) + varepsilon)} le p (x _ 1 ^ n) le 2 ^ {-n (h (x)-varepsilon)} </math > <br />
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:::<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
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<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
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2 ^ {-n (h (y) + varepsilon)} le p (y _ 1 ^ n) le 2 ^ {-n (h (y)-varepsilon)}<br />
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:::<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
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<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
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{2 ^ {-n (h (x,y) + varepsilon)} le p (x _ 1 ^ n,y _ 1 ^ n) le 2 ^ {-n (h (x,y)-varepsilon)}<br />
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We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are ''jointly typical'' if they lie in the jointly typical set defined above.<br />
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We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are jointly typical if they lie in the jointly typical set defined above.<br />
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我们说两个序列X1n和Y1n如果它们位于上面定义的联合典型集合中,那么它们是共同典型的。<br />
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'''Steps'''<br />
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Steps<br />
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步骤<br />
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#In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
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In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
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在随机编码参数的风格中,我们随机从概率分布 q 生成长度为 n 的长度为2nR的码字。<br />
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#This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
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This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
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这段代码向发送者和接收者显示。还假设人们知道所使用的通道的转移矩阵。<br />
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#A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
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A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
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根据码字集上的均匀分布选择消息 w。也就是,Pr (w = w) = 2-nR ,w = 1,2,,2nR。<br />
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#The message W is sent across the channel.<br />
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The message W is sent across the channel.<br />
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消息 w 是通过通道发送的。<br />
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#The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
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The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
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接收端根据P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))接收一个序列<br />
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#Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called ''typical set decoding''.<br />
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Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called typical set decoding.<br />
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通过信道发送这些码字,我们接收到Y1n,并解码到某个源序列,如果存在正好与 y 共同典型的一个码字。如果没有共同的典型代码字,或者有多个代码字,则声明错误。如果解码的码字与原始码字不匹配,也会发生错误。这就是所谓的典型集合译码。<br />
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The probability of error of this scheme is divided into two parts:<br />
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The probability of error of this scheme is divided into two parts:<br />
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该方案的误差概率分为两部分:<br />
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#First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
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First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
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首先,如果没有为接收到的 y 序列找到联合的典型 x 序列,就可能发生错误<br />
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#Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
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Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
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其次,如果一个不正确的 x 序列与一个接收到的 y 序列是共同的典型,则可能发生错误。<br />
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*By the randomness of the code construction, we can assume that the average probability of error averaged over all codes does not depend on the index sent. Thus, without loss of generality, we can assume ''W'' = 1.<br />
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*From the joint AEP, we know that the probability that no jointly typical X exists goes to 0 as n grows large. We can bound this error probability by <math>\varepsilon</math>.<br />
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*Also from the joint AEP, we know the probability that a particular <math>X_1^{n}(i)</math> and the <math>Y_1^n</math> resulting from ''W'' = 1 are jointly typical is <math>\le 2^{-n(I(X;Y) - 3\varepsilon)}</math>.<br />
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Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
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Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
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as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
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as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
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作为消息 i 与消息1发送时接收到的序列一起发生的典型事件。<br />
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: <math><br />
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《数学》<br />
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\begin{align}<br />
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\begin{align}<br />
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开始{ align }<br />
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P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
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P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
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P (text { error }) & {} = p (text { error } | w = 1) le p (e_1 ^ c) + sum _ { i = 2} ^ {2 ^ { nR }} p (e_i)<br />
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& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
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& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
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& {} le p (e _ 1 ^ c) + (2 ^ { nR }-1)2 ^ {-n (i (x; y)-3 varepsilon)}<br />
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& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
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& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
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& {} le varepsilon + 2 ^ {-n (i (x; y)-R-3 varepsilon)}.<br />
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\end{align}<br />
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\end{align}<br />
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结束{ align }<br />
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We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
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We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
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我们可以观察到,当n趋于无穷大时,如果R<I(X;Y)对于通道,错误概率将趋于0。<br />
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Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
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Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
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最后,假设平均码本是“好的” ,我们知道存在一个性能优于平均值的码本,从而满足了我们在噪声信道中任意低错误概率通信的需要。<br />
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=== Weak converse for discrete memoryless channels离散无记忆信道的弱逆===<br />
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Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
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Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
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假设一个2nR代码字的代码。让 w 作为索引均匀地绘制在这个集合上。让 x ^ n和 y ^ n 分别作为传输代码和接收代码。<br />
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#<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and [[mutual information]]<br />
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<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and mutual information<br />
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使用包含熵和互信息的恒等式nR=H(W)=H(W|Yn)+I(W;Yn)<br />
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#<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
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<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
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因为 x 是 w 的一个函数,所以它是一个数学公式<br />
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#<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of [[Fano's Inequality]]<br />
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<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of Fano's Inequality<br />
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利用 Fano 不等式,得到了一个新的数学公式≤1+Pe(n)nR+I(Xn(W);Yn)<br />
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#<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
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<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
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由于容量是最大化的互信息,因此≤1+Pe(n)nR+nC。<br />
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The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
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The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
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这些步骤的结果是Pe(n)≥1−1nR−CR。当块长度n 趋于无穷大时,我们得到当R大于C时Pe(n)远离0,我们只有当R小于C时才能得到任意低的误差率。<br />
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=== Strong converse for discrete memoryless channels离散无记忆信道的强逆 ===<br />
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A strong converse theorem, proven by Wolfowitz in 1957,<ref>Robert Gallager. ''Information Theory and Reliable Communication.'' New York: [[John Wiley & Sons]], 1968. {{ISBN|0-471-29048-3}}</ref> states that,<br />
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A strong converse theorem, proven by Wolfowitz in 1957, states that,<br />
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沃尔福威茨在1957年证明了一个强逆定理,<br />
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:<math><br />
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《数学》<br />
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P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
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P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
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P _ e geq 1-frac {4A }{ n (R-C) ^ 2}-e ^ {-frac { n (R-C)}{2}<br />
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</math><br />
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</math><br />
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for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
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for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
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为了某个有限的正常数。当弱逆表示错误概率远离零是有界的时候,强逆表示错误概率远离零是有界的。因此,C是完全可靠和完全不可靠的通信之间的一个尖锐的门槛。<br />
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== Channel coding theorem for non-stationary memoryless channels==<br />
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We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
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We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
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我们假设信道是无记忆的,但是它的跃迁概率随时间而变化,这种变化在发射机和接收机中都是已知的。<br />
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Then the channel capacity is given by<br />
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Then the channel capacity is given by<br />
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然后通过对信道容量的分析,给出信道容量的计算公式<br />
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:<math> <br />
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<math> <br />
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《数学》<br />
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C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
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C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
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C = lim inf max { p ^ {(x _ 1)} ,p ^ {(x _ 2)} ,... } frac {1}{ n } sum { i = 1} ^ nI (x _ i; y _ i).<br />
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</math><br />
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The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
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The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
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在每个通道的容量分配上达到最大值。就是,<br />
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<math><br />
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<math><br />
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《数学》<br />
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C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
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C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
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1}{ n } sum { i = 1} ^ n c _ i<br />
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</math><br />
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</math><br />
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where <math>C_i</math> is the capacity of the i''th'' channel.<br />
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where <math>C_i</math> is the capacity of the ith channel.<br />
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其中Ci是第i通道的容量。<br />
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=== Outline of the proof证明概述===<br />
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The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the [[asymptotic equipartition property]] article.<br />
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The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the asymptotic equipartition property article.<br />
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该证明与信道编码定理的证明几乎相同。可实现性来自随机编码,每个符号从该特定信道的容量实现分布中随机选择。典型性参数使用渐近均分性质文章中定义的非平稳源的典型集的定义<br />
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The technicality of [[lim inf]] comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
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The technicality of lim inf comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
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当 1n∑i=1nCi不收敛时,lim inf 的技术性就发挥了作用。<br />
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==See also参见==<br />
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* [[Asymptotic equipartition property]] (AEP)<br />
渐近均分性 <br />
* [[Fano's inequality]]<br />
法诺不等式<br />
* [[Rate–distortion theory]]<br />
率失真理论<br />
* [[Shannon's source coding theorem]]<br />
香农信源编码定理<br />
* [[Shannon–Hartley theorem]]<br />
香农-哈特莱定理 <br />
* [[Turbo code]]<br />
涡轮码<br />
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==Notes批注==<br />
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{{reflist}}<br />
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==References参考==<br />
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* [[Thomas M. Cover|Cover T. M.]], Thomas J. A., ''Elements of Information Theory'', [[John Wiley & Sons]], 1991. {{ISBN|0-471-06259-6}}<br />
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*[[Fano|Fano, R. A.]], ''Transmission of information; a statistical theory of communications'', [[MIT Press]], 1961. {{ISBN|0-262-06001-9}}<br />
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*[[Amiel Feinstein|Feinstein, Amiel]], "A New basic theorem of information theory", ''[[IEEE Transactions on Information Theory]]'', 4(4): 2-22, 1954.<br />
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* [[David J.C. MacKay|MacKay, David J. C.]], ''[http://www.inference.phy.cam.ac.uk/mackay/itila/book.html Information Theory, Inference, and Learning Algorithms]'', [[Cambridge University Press]], 2003. {{ISBN|0-521-64298-1}} [free online]<br />
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*[[Claude E. Shannon|Shannon, C. E.]], [https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6773024 ''A Mathematical Theory of Communication'']. ''The Bell System Technical Journal'' 27,3: 379–423, 1948.<br />
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*[[Claude E. Shannon|Shannon, C. E.]], [http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html ''A Mathematical Theory of Communication''] Urbana, IL: University of Illinois Press, 1948 (reprinted 1998).<br />
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*[[Wolfowitz| Wolfowitz, J.]], "[https://projecteuclid.org/download/pdf_1/euclid.ijm/1255380682 The coding of messages subject to chance errors]", ''Illinois J. Math.'', 1: 591–606, 1957.<br />
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==External links外部链接==<br />
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* [http://www.cs.miami.edu/home/burt/learning/Csc524.142/LarsTelektronikk02.pdf On Shannon and Shannon's law]<br />
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* [http://cnx.org/content/m10180/latest/ Shannon's Noisy Channel Coding Theorem]<br />
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{{DEFAULTSORT:Noisy-Channel Coding Theorem}}<br />
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[[Category:Information theory]]<br />
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Category:Information theory<br />
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范畴: 信息论<br />
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[[Category:Theorems in discrete mathematics]]<br />
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Category:Theorems in discrete mathematics<br />
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范畴: 离散数学的定理<br />
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[[Category:Telecommunication theory]]<br />
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Category:Telecommunication theory<br />
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范畴: 电信理论<br />
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[[Category:Coding theory]]<br />
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Category:Coding theory<br />
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类别: 编码理论<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Noisy-channel coding theorem]]. Its edit history can be viewed at [[有噪信道编码定理/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%9C%89%E5%99%AA%E4%BF%A1%E9%81%93%E7%BC%96%E7%A0%81%E5%AE%9A%E7%90%86&diff=20914有噪信道编码定理2021-01-15T08:51:08Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Limit on data transfer rate}}<br />
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{{Information theory}}<br />
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{{redirect|Shannon's theorem|text=Shannon's name is also associated with the [[sampling theorem]]}}<br />
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In [[information theory]], the '''noisy-channel coding theorem''' (sometimes '''Shannon's theorem''' or '''Shannon's limit'''), establishes that for any given degree of [[Noisy channel model|noise contamination of a communication channel]], it is possible to communicate discrete data (digital [[information]]) nearly error-free up to a computable maximum rate through the channel. This result was presented by [[Claude Shannon]] in 1948 and was based in part on earlier work and ideas of [[Harry Nyquist]] and [[Ralph Hartley]].<br />
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In information theory, the noisy-channel coding theorem (sometimes Shannon's theorem or Shannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible to communicate discrete data (digital information) nearly error-free up to a computable maximum rate through the channel. This result was presented by Claude Shannon in 1948 and was based in part on earlier work and ideas of Harry Nyquist and Ralph Hartley.<br />
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在信息论中,有噪声信道编码定理(有时是香农定理或香农极限)确定了对于通信信道的任何给定程度的噪声污染,都有可能通过信道传输几乎无差错的离散数据(数字信息),从而达到可计算的最大速率。这个结果是由克劳德·香农在1948年提出的,部分基于哈利·奈奎斯特和拉尔夫·哈特利早期的工作和思想。<br />
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The '''Shannon limit''' or '''Shannon capacity''' of a communication channel refers to the maximum [[Code rate|rate]] of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by [[Claude E. Shannon|Claude Elwood Shannon]] and [[Warren Weaver]] in [[1949]] entitled ''The Mathematical Theory of Communication.'' ({{ISBN|0252725484}}). This founded the modern discipline of [[information theory]]. <br />
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The Shannon limit or Shannon capacity of a communication channel refers to the maximum rate of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by Claude Elwood Shannon and Warren Weaver in 1949 entitled The Mathematical Theory of Communication. (). This founded the modern discipline of information theory. <br />
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通信信道的香农极限或香农容量是指在特定噪声水平下,如果链路受到随机数据传输错误的影响,理论上可以通过信道传输的最大无错误数据速率。它最早由香农(1948)描述,不久后在1949年由克劳德·埃尔伍德·香农和沃伦·韦弗出版的一本书中发表,书名为《通信的数学理论》。这奠定了现代信息论学科的基础。 <br />
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== Overview 总览==<br />
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Stated by [[Claude Shannon]] in 1948, the theorem describes the maximum possible efficiency of [[error-correcting code|error-correcting methods]] versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and [[data storage device|data storage]]. This theorem is of foundational importance to the modern field of [[information theory]]. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to [[Amiel Feinstein]]<ref>{{Cite journal|date=1954|others=Feinstein, Amiel.|title=A new basic theorem of information theory|hdl=1721.1/4798|bibcode=1955PhDT........12F}}</ref> in 1954.<br />
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Stated by Claude Shannon in 1948, the theorem describes the maximum possible efficiency of error-correcting methods versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and data storage. This theorem is of foundational importance to the modern field of information theory. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to Amiel Feinstein in 1954.<br />
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香农在1948年提出的定理描述了纠错方法的最大可能效率与噪声干扰和数据损坏程度的关系。香农定理在通信和数据存储中都有广泛的应用。这个定理对现代信息论领域具有重要的基础性意义。香农只概述了证明。1954年,阿米尔·范斯坦提出了离散情况的第一个严格证明。<br />
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The Shannon theorem states that given a noisy channel with [[channel capacity]] ''C'' and information transmitted at a rate ''R'', then if <math>R < C</math> there exist [[code]]s that allow the [[probability of error]] at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, ''C''.<br />
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The Shannon theorem states that given a noisy channel with channel capacity C and information transmitted at a rate R, then if <math>R < C</math> there exist codes that allow the probability of error at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, C.<br />
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香农定理指出,给定一个信道容量为C的噪声信道和以R速率传输的信息,那么如果R<C,则存在允许接收机处的错误概率任意小的码。这意味着,从理论上讲,以低于极限速率C的任何速率几乎无误地传输信息是可能的。<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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定理反过来也很重要。如果R>C,任意小的错误概率都是不可能实现的。所有代码的错误概率都将大于某个正最小水平,并且该水平随着速率的增加而增加。因此,不能保证信息以超出信道容量的速率可靠地跨信道传输。这个定理并不适用于速率和容量相等的罕见情况<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the [[Shannon–Hartley theorem]].<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the Shannon–Hartley theorem.<br />
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信道容量C可以从信道的物理特性计算出来,对于带有高斯噪声的带限信道,可以使用香农-哈特莱定理。<br />
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Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as [[Reed–Solomon code]]s and, more recently, [[low-density parity-check code|low-density parity-check]] (LDPC) codes and [[turbo code]]s, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's [[digital signal processors]], it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary [[Additive white Gaussian noise]] (AWGN) channels, with very long block lengths).<ref>[[Sae-Young Chung]], [[G. David Forney, Jr.]], [[Thomas J. Richardson]], and [[Rüdiger Urbanke]], "[http://www.josephboutros.org/ldpc_vs_turbo/ldpc_Chung_CLfeb01.pdf On the Design of Low-Density Parity-Check Codes within 0.0045 dB of the Shannon Limit]", ''[[IEEE Communications Letters]]'', 5: 58-60, Feb. 2001. ISSN 1089-7798</ref><br />
<br />
Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as Reed–Solomon codes and, more recently, low-density parity-check (LDPC) codes and turbo codes, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's digital signal processors, it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary Additive white Gaussian noise (AWGN) channels, with very long block lengths).<br />
<br />
诸如“发送消息3次,如果副本不同,则使用3选2最佳投票方案”之类的简单方案是低效的纠错方法,无法渐近地保证数据块可以无错误地通信。诸如Reed-Solomon码以及最近的低密度奇偶校验(LDPC)码和turbo码之类的先进技术更接近于达到理论上的香农极限,但代价是计算复杂度很高。使用这些高效的代码和当今数字信号处理器的计算能力,现在有可能达到非常接近香农极限。事实上,LDPC码可以达到香农极限的0.0045dB以内(对于二进制加性高斯白噪声(AWGN)信道,具有很长的块长度)。 。<br />
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== Mathematical statement数学表述 ==<br />
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The basic mathematical model for a communication system is the following:<br />
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The basic mathematical model for a communication system is the following:<br />
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通信系统的基本数学模型如下:<br />
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[[File:Channel model.svg|center|800px|Channel model]]<br />
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Channel model<br />
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通道模型<br />
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A '''message''' ''W'' is transmitted through a noisy channel by using encoding and decoding functions. An '''encoder''' maps ''W'' into a pre-defined sequence of channel symbols of length ''n''. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a '''decoder''' which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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A message W is transmitted through a noisy channel by using encoding and decoding functions. An encoder maps W into a pre-defined sequence of channel symbols of length n. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a decoder which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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通过使用编码和解码功能,通过噪声信道传送消息W。编码器将W映射到长度为n的预定义信道符号序列中。在其最基本的模型中,信道独立于其他符号而扭曲这些符号中的每一个。信道的输出——接收到的序列——被送入解码器,解码器将序列映射成消息的估计。在此设置中,错误概率定义为:<br />
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::<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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[数学 > p _ e = 文本{ Pr }左{ w } neq w 右}。数学<br />
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'''Theorem''' (Shannon, 1948):<br />
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Theorem (Shannon, 1948):<br />
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定理(Shannon,1948) :<br />
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:1. For every discrete memoryless channel, the [[channel capacity]] is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1. For every discrete memoryless channel, the channel capacity is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1.对于每一个离散的无记忆信道,信道容量是根据互信息I(x; y)来定义的,<br />
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::<math>\ C = \sup_{p_X} I(X;Y)</math><ref>For a description of the "sup" function, see [[Supremum]]</ref><br />
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<math>\ C = \sup_{p_X} I(X;Y)</math><br />
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[ math > c = sup { p _ x } i (x; y) </math ]<br />
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:has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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具有以下属性。对于任何ε>0 和 R<C ,对于足够大的N ,存在一个长度为 N 和速率R的代码和一个解码算法,使得块错误的最大概率为ε 。<br />
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:2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2.如果位错概率pb是可以接受的,那么达到R(pb)的速率是可以实现的<br />
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::<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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1-H _ 2(p _ b)} . </math > <br />
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:and <math> H_2(p_b)</math> is the ''[[binary entropy function]]''<br />
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and <math> H_2(p_b)</math> is the binary entropy function<br />
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2(p _ b) </math > 是二元熵函数<br />
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::<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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< math > h _ 2(p _ b) =-左[ p _ b log_2{ p _ b } + (1-p _ b) log_2({1-p _ b })右] </math > <br />
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:3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3.对于任何pb ,比率大于R(pb)是无法实现的。<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003) ,第162页; cf Gallager (1968) ,第5章; Cover and Thomas (1991) ,第198页; Shannon (1948) thm。11)<br />
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== Outline of proof证明概述 ==<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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结合信息论中的其他几个主要结果,噪声信道编码定理的证明包括一个可达性结果和一个匹配逆结果。在这种情况下,这两个分量用来限定一个人在噪声信道上进行通信的可能速率集,而匹配用来表明这些界限是紧界限。<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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下面的提纲只是信息论文本中可供学习的许多不同风格中的一组 <br />
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===Achievability for discrete memoryless channels离散无记忆信道的可达性===<br />
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This particular proof of achievability follows the style of proofs that make use of the [[asymptotic equipartition property]] (AEP). Another style can be found in information theory texts using [[error exponent]]s.<br />
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This particular proof of achievability follows the style of proofs that make use of the asymptotic equipartition property (AEP). Another style can be found in information theory texts using error exponents.<br />
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这个特殊的可实现性证明遵循了利用渐近均分性质(AEP)的证明风格。另一种风格可以在信息论文本中找到使用错误指数。 <br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the [[channel capacity]].<br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the channel capacity.<br />
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这两种类型的证明都使用了一个随机编码参数,其中跨信道使用的码本是随机构造的-这使得分析更简单,同时仍然证明在低于信道容量的任何数据速率下,存在满足期望的低错误概率的码。 <br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a ''jointly typical set'' by the following:<br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a jointly typical set by the following:<br />
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通过一个与 aep-相关的参数,给定一个通道,长度 < math > n </math > 源符号的字符串 < math > x _ 1 ^ { n } </math > ,以及长度 < math > n </math > n </math > 通道输出的字符串 < math > y _ 1 ^ { n } </math > ,我们可以定义一个联合的典型集合如下:<br />
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: <math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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<math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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数学 x ^ n 乘以数学 y ^ n </math > <br />
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:::<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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2 ^ {-n (h (x) + varepsilon)} le p (x _ 1 ^ n) le 2 ^ {-n (h (x)-varepsilon)} </math > <br />
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:::<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
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<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
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2 ^ {-n (h (y) + varepsilon)} le p (y _ 1 ^ n) le 2 ^ {-n (h (y)-varepsilon)}<br />
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:::<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
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<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
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{2 ^ {-n (h (x,y) + varepsilon)} le p (x _ 1 ^ n,y _ 1 ^ n) le 2 ^ {-n (h (x,y)-varepsilon)}<br />
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We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are ''jointly typical'' if they lie in the jointly typical set defined above.<br />
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We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are jointly typical if they lie in the jointly typical set defined above.<br />
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我们说两个序列 < math > { x1 ^ n } </math > 和 < math > y _ 1 ^ n </math > 如果它们位于上面定义的联合典型集合中,那么它们是共同典型的。<br />
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'''Steps'''<br />
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Steps<br />
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步骤<br />
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#In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
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In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
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在随机编码参数的风格中,我们随机从概率分布 q 生成长度为 n 的长度为2 ^ { nR } </math > 的码字。<br />
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#This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
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This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
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这段代码向发送者和接收者显示。还假设人们知道所使用的通道的转移矩阵。<br />
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#A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
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A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
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根据码字集上的均匀分布选择消息 w。也就是,< math > Pr (w = w) = 2 ^ {-nR } ,w = 1,2,dots,2 ^ { nR } </math > 。<br />
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#The message W is sent across the channel.<br />
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The message W is sent across the channel.<br />
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消息 w 是通过通道发送的。<br />
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#The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
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The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
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接收端根据 < math > p (y ^ n | x ^ n (w)) = prod _ { i = 1} ^ np (y _ i | x _ i (w)) </math > 接收一个序列<br />
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#Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called ''typical set decoding''.<br />
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Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called typical set decoding.<br />
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通过信道发送这些码字,我们接收到 y _ (1 ^ n) </math > ,并解码到某个源序列,如果存在正好与 y 共同典型的一个码字。如果没有共同的典型代码字,或者有多个代码字,则声明错误。如果解码的码字与原始码字不匹配,也会发生错误。这就是所谓的典型集合译码。<br />
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The probability of error of this scheme is divided into two parts:<br />
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The probability of error of this scheme is divided into two parts:<br />
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该方案的误差概率分为两部分:<br />
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#First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
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First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
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首先,如果没有为接收到的 y 序列找到联合的典型 x 序列,就可能发生错误<br />
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#Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
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Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
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其次,如果一个不正确的 x 序列与一个接收到的 y 序列是共同的典型,则可能发生错误。<br />
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*By the randomness of the code construction, we can assume that the average probability of error averaged over all codes does not depend on the index sent. Thus, without loss of generality, we can assume ''W'' = 1.<br />
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*From the joint AEP, we know that the probability that no jointly typical X exists goes to 0 as n grows large. We can bound this error probability by <math>\varepsilon</math>.<br />
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*Also from the joint AEP, we know the probability that a particular <math>X_1^{n}(i)</math> and the <math>Y_1^n</math> resulting from ''W'' = 1 are jointly typical is <math>\le 2^{-n(I(X;Y) - 3\varepsilon)}</math>.<br />
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Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
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Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
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定义: < math > e _ i = {(x _ 1 ^ n (i) ,y _ 1 ^ n) in a _ varepsilon ^ {(n)}} ,i = 1,2,dots,2 ^ { nR } </math > <br />
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as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
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as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
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作为消息 i 与消息1发送时接收到的序列一起发生的典型事件。<br />
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: <math><br />
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<math><br />
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《数学》<br />
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\begin{align}<br />
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\begin{align}<br />
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开始{ align }<br />
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P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
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P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
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P (text { error }) & {} = p (text { error } | w = 1) le p (e_1 ^ c) + sum _ { i = 2} ^ {2 ^ { nR }} p (e_i)<br />
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& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
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& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
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& {} le p (e _ 1 ^ c) + (2 ^ { nR }-1)2 ^ {-n (i (x; y)-3 varepsilon)}<br />
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& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
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& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
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& {} le varepsilon + 2 ^ {-n (i (x; y)-R-3 varepsilon)}.<br />
<br />
\end{align}<br />
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\end{align}<br />
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结束{ align }<br />
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</math><br />
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</math><br />
<br />
数学<br />
<br />
<br />
<br />
We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
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We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
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我们可以观察到,当 < math > n </math > 趋于无穷大时,如果 < math > r < i (x; y) </math > 对于通道,错误概率将趋于0。<br />
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<br />
Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
<br />
Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
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最后,假设平均码本是“好的” ,我们知道存在一个性能优于平均值的码本,从而满足了我们在噪声信道中任意低错误概率通信的需要。<br />
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<br />
<br />
=== Weak converse for discrete memoryless channels===<br />
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<br />
Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
<br />
Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
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假设一个 < math > 2 ^ { nR } </math > 代码字的代码。让 w 作为索引均匀地绘制在这个集合上。让 < math > x ^ n </math > 和 < math > y ^ n </math > 分别作为传输代码和接收代码。<br />
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#<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and [[mutual information]]<br />
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<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and mutual information<br />
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使用包含熵和互信息的恒等式 < math > nR = h (w) = h (w | y ^ n) + i (w; y ^ n) </math<br />
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#<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
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<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
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因为 x 是 w 的一个函数,所以它是一个数学公式<br />
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#<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of [[Fano's Inequality]]<br />
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<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of Fano's Inequality<br />
<br />
利用 Fano 不等式,得到了一个新的数学公式: (1 + p _ e ^ {(n)} nR + i (x ^ n (w) ; y ^ n) </math<br />
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#<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
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<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
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由于容量是最大化的互信息,因此[ math > le 1 + p _ e ^ {(n)} nR + nC。<br />
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The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
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The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
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这些步骤的结果是 < math > p _ e ^ {(n)} ge 1-frac {1}{ nR }-frac { c }{ r }{ math > 。当块长度 < math > n </math > 趋于无穷大时,我们得到当 r 大于 c 时 < math > p _ e ^ {(n)} </math > 远离0,我们只有当 r 小于 c 时才能得到任意低的误差率。<br />
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=== Strong converse for discrete memoryless channels ===<br />
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A strong converse theorem, proven by Wolfowitz in 1957,<ref>Robert Gallager. ''Information Theory and Reliable Communication.'' New York: [[John Wiley & Sons]], 1968. {{ISBN|0-471-29048-3}}</ref> states that,<br />
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A strong converse theorem, proven by Wolfowitz in 1957, states that,<br />
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沃尔福威茨在1957年证明了一个强逆定理,<br />
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:<math><br />
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<math><br />
<br />
《数学》<br />
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P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
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P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
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P _ e geq 1-frac {4A }{ n (R-C) ^ 2}-e ^ {-frac { n (R-C)}{2}<br />
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</math><br />
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</math><br />
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数学<br />
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for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
<br />
for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
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为了某个有限的正常数。当弱逆表示错误概率远离零是有界的时候,强逆表示错误概率远离零是有界的。因此,c </math > 是完全可靠和完全不可靠的通信之间的一个尖锐的门槛。<br />
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== Channel coding theorem for non-stationary memoryless channels==<br />
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We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
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We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
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我们假设信道是无记忆的,但是它的跃迁概率随时间而变化,这种变化在发射机和接收机中都是已知的。<br />
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Then the channel capacity is given by<br />
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Then the channel capacity is given by<br />
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然后通过对信道容量的分析,给出信道容量的计算公式<br />
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:<math> <br />
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<math> <br />
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《数学》<br />
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C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
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C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
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C = lim inf max { p ^ {(x _ 1)} ,p ^ {(x _ 2)} ,... } frac {1}{ n } sum { i = 1} ^ nI (x _ i; y _ i).<br />
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</math><br />
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</math><br />
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The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
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The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
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在每个通道的容量分配上达到最大值。就是,<br />
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<math><br />
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<math><br />
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《数学》<br />
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C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
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C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
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1}{ n } sum { i = 1} ^ n c _ i<br />
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</math><br />
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</math><br />
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数学<br />
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where <math>C_i</math> is the capacity of the i''th'' channel.<br />
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where <math>C_i</math> is the capacity of the ith channel.<br />
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其中 c _ i </math > 是第 i 通道的容量。<br />
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=== Outline of the proof===<br />
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The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the [[asymptotic equipartition property]] article.<br />
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The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the asymptotic equipartition property article.<br />
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证明过程与信道编码定理的证明过程几乎一样。可实现性遵循从特定信道的容量实现分布中随机选择每个符号的随机编码。典型论证使用的定义,典型集定义为非平稳的来源定义在渐近等同分割特性文章。<br />
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The technicality of [[lim inf]] comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
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The technicality of lim inf comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
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当[ math ]{ n } sum { i = 1} ^ n c _ i </math > 不收敛时,lim inf 的技术性就发挥了作用。<br />
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==See also==<br />
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* [[Asymptotic equipartition property]] (AEP)<br />
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* [[Fano's inequality]]<br />
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* [[Rate–distortion theory]]<br />
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* [[Shannon's source coding theorem]]<br />
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* [[Shannon–Hartley theorem]]<br />
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* [[Turbo code]]<br />
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==Notes==<br />
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{{reflist}}<br />
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==References==<br />
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* [[Thomas M. Cover|Cover T. M.]], Thomas J. A., ''Elements of Information Theory'', [[John Wiley & Sons]], 1991. {{ISBN|0-471-06259-6}}<br />
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*[[Fano|Fano, R. A.]], ''Transmission of information; a statistical theory of communications'', [[MIT Press]], 1961. {{ISBN|0-262-06001-9}}<br />
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*[[Amiel Feinstein|Feinstein, Amiel]], "A New basic theorem of information theory", ''[[IEEE Transactions on Information Theory]]'', 4(4): 2-22, 1954.<br />
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* [[David J.C. MacKay|MacKay, David J. C.]], ''[http://www.inference.phy.cam.ac.uk/mackay/itila/book.html Information Theory, Inference, and Learning Algorithms]'', [[Cambridge University Press]], 2003. {{ISBN|0-521-64298-1}} [free online]<br />
<br />
*[[Claude E. Shannon|Shannon, C. E.]], [https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6773024 ''A Mathematical Theory of Communication'']. ''The Bell System Technical Journal'' 27,3: 379–423, 1948.<br />
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*[[Claude E. Shannon|Shannon, C. E.]], [http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html ''A Mathematical Theory of Communication''] Urbana, IL: University of Illinois Press, 1948 (reprinted 1998).<br />
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*[[Wolfowitz| Wolfowitz, J.]], "[https://projecteuclid.org/download/pdf_1/euclid.ijm/1255380682 The coding of messages subject to chance errors]", ''Illinois J. Math.'', 1: 591–606, 1957.<br />
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==External links==<br />
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* [http://www.cs.miami.edu/home/burt/learning/Csc524.142/LarsTelektronikk02.pdf On Shannon and Shannon's law]<br />
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* [http://cnx.org/content/m10180/latest/ Shannon's Noisy Channel Coding Theorem]<br />
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{{DEFAULTSORT:Noisy-Channel Coding Theorem}}<br />
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[[Category:Information theory]]<br />
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Category:Information theory<br />
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范畴: 信息论<br />
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[[Category:Theorems in discrete mathematics]]<br />
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Category:Theorems in discrete mathematics<br />
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范畴: 离散数学的定理<br />
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[[Category:Telecommunication theory]]<br />
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Category:Telecommunication theory<br />
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范畴: 电信理论<br />
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[[Category:Coding theory]]<br />
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Category:Coding theory<br />
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类别: 编码理论<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Noisy-channel coding theorem]]. Its edit history can be viewed at [[有噪信道编码定理/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%9C%89%E5%99%AA%E4%BF%A1%E9%81%93%E7%BC%96%E7%A0%81%E5%AE%9A%E7%90%86&diff=20913有噪信道编码定理2021-01-15T08:41:14Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Limit on data transfer rate}}<br />
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{{Information theory}}<br />
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{{redirect|Shannon's theorem|text=Shannon's name is also associated with the [[sampling theorem]]}}<br />
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In [[information theory]], the '''noisy-channel coding theorem''' (sometimes '''Shannon's theorem''' or '''Shannon's limit'''), establishes that for any given degree of [[Noisy channel model|noise contamination of a communication channel]], it is possible to communicate discrete data (digital [[information]]) nearly error-free up to a computable maximum rate through the channel. This result was presented by [[Claude Shannon]] in 1948 and was based in part on earlier work and ideas of [[Harry Nyquist]] and [[Ralph Hartley]].<br />
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In information theory, the noisy-channel coding theorem (sometimes Shannon's theorem or Shannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible to communicate discrete data (digital information) nearly error-free up to a computable maximum rate through the channel. This result was presented by Claude Shannon in 1948 and was based in part on earlier work and ideas of Harry Nyquist and Ralph Hartley.<br />
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在信息论中,有噪声信道编码定理(有时是香农定理或香农极限)确定了对于通信信道的任何给定程度的噪声污染,都有可能通过信道传输几乎无差错的离散数据(数字信息),从而达到可计算的最大速率。这个结果是由克劳德·香农在1948年提出的,部分基于哈利·奈奎斯特和拉尔夫·哈特利早期的工作和思想。<br />
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The '''Shannon limit''' or '''Shannon capacity''' of a communication channel refers to the maximum [[Code rate|rate]] of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by [[Claude E. Shannon|Claude Elwood Shannon]] and [[Warren Weaver]] in [[1949]] entitled ''The Mathematical Theory of Communication.'' ({{ISBN|0252725484}}). This founded the modern discipline of [[information theory]]. <br />
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The Shannon limit or Shannon capacity of a communication channel refers to the maximum rate of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by Claude Elwood Shannon and Warren Weaver in 1949 entitled The Mathematical Theory of Communication. (). This founded the modern discipline of information theory. <br />
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通信信道的香农极限或香农容量是指在特定噪声水平下,如果链路受到随机数据传输错误的影响,理论上可以通过信道传输的最大无错误数据速率。它最早由香农(1948)描述,不久后在1949年由克劳德·埃尔伍德·香农和沃伦·韦弗出版的一本书中发表,书名为《通信的数学理论》。这奠定了现代信息论学科的基础。 <br />
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== Overview 总览==<br />
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Stated by [[Claude Shannon]] in 1948, the theorem describes the maximum possible efficiency of [[error-correcting code|error-correcting methods]] versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and [[data storage device|data storage]]. This theorem is of foundational importance to the modern field of [[information theory]]. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to [[Amiel Feinstein]]<ref>{{Cite journal|date=1954|others=Feinstein, Amiel.|title=A new basic theorem of information theory|hdl=1721.1/4798|bibcode=1955PhDT........12F}}</ref> in 1954.<br />
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Stated by Claude Shannon in 1948, the theorem describes the maximum possible efficiency of error-correcting methods versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and data storage. This theorem is of foundational importance to the modern field of information theory. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is due to Amiel Feinstein in 1954.<br />
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香农在1948年提出的定理描述了纠错方法的最大可能效率与噪声干扰和数据损坏程度的关系。香农定理在通信和数据存储中都有广泛的应用。这个定理对现代信息论领域具有重要的基础性意义。香农只概述了证明。1954年,阿米尔·范斯坦提出了离散情况的第一个严格证明。<br />
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The Shannon theorem states that given a noisy channel with [[channel capacity]] ''C'' and information transmitted at a rate ''R'', then if <math>R < C</math> there exist [[code]]s that allow the [[probability of error]] at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, ''C''.<br />
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The Shannon theorem states that given a noisy channel with channel capacity C and information transmitted at a rate R, then if <math>R < C</math> there exist codes that allow the probability of error at the receiver to be made arbitrarily small. This means that, theoretically, it is possible to transmit information nearly without error at any rate below a limiting rate, C.<br />
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香农定理指出,给定一个信道容量为C的噪声信道和以R速率传输的信息,那么如果R<C,则存在允许接收机处的错误概率任意小的码。这意味着,从理论上讲,以低于极限速率C的任何速率几乎无误地传输信息是可能的。<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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The converse is also important. If <math>R > C</math>, an arbitrarily small probability of error is not achievable. All codes will have a probability of error greater than a certain positive minimal level, and this level increases as the rate increases. So, information cannot be guaranteed to be transmitted reliably across a channel at rates beyond the channel capacity. The theorem does not address the rare situation in which rate and capacity are equal.<br />
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定理反过来也很重要。如果R>C,任意小的错误概率都是不可能实现的。所有代码的错误概率都将大于某个正最小水平,并且该水平随着速率的增加而增加。因此,不能保证信息以超出信道容量的速率可靠地跨信道传输。这个定理并不适用于速率和容量相等的罕见情况<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the [[Shannon–Hartley theorem]].<br />
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The channel capacity <math>C</math> can be calculated from the physical properties of a channel; for a band-limited channel with Gaussian noise, using the Shannon–Hartley theorem.<br />
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信道容量C可以从信道的物理特性计算出来,对于带有高斯噪声的带限信道,可以使用香农-哈特莱定理。<br />
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Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as [[Reed–Solomon code]]s and, more recently, [[low-density parity-check code|low-density parity-check]] (LDPC) codes and [[turbo code]]s, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's [[digital signal processors]], it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary [[Additive white Gaussian noise]] (AWGN) channels, with very long block lengths).<ref>[[Sae-Young Chung]], [[G. David Forney, Jr.]], [[Thomas J. Richardson]], and [[Rüdiger Urbanke]], "[http://www.josephboutros.org/ldpc_vs_turbo/ldpc_Chung_CLfeb01.pdf On the Design of Low-Density Parity-Check Codes within 0.0045 dB of the Shannon Limit]", ''[[IEEE Communications Letters]]'', 5: 58-60, Feb. 2001. ISSN 1089-7798</ref><br />
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Simple schemes such as "send the message 3 times and use a best 2 out of 3 voting scheme if the copies differ" are inefficient error-correction methods, unable to asymptotically guarantee that a block of data can be communicated free of error. Advanced techniques such as Reed–Solomon codes and, more recently, low-density parity-check (LDPC) codes and turbo codes, come much closer to reaching the theoretical Shannon limit, but at a cost of high computational complexity. Using these highly efficient codes and with the computing power in today's digital signal processors, it is now possible to reach very close to the Shannon limit. In fact, it was shown that LDPC codes can reach within 0.0045&nbsp;dB of the Shannon limit (for binary Additive white Gaussian noise (AWGN) channels, with very long block lengths).<br />
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诸如“发送消息3次,如果副本不同,则使用3选2最佳投票方案”之类的简单方案是低效的纠错方法,无法渐近地保证数据块可以无错误地通信。诸如Reed-Solomon码以及最近的低密度奇偶校验(LDPC)码和turbo码之类的先进技术更接近于达到理论上的香农极限,但代价是计算复杂度很高。使用这些高效的代码和当今数字信号处理器的计算能力,现在有可能达到非常接近香农极限。事实上,LDPC码可以达到香农极限的0.0045dB以内(对于二进制加性高斯白噪声(AWGN)信道,具有很长的块长度)。 。<br />
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== Mathematical statement数学表述 ==<br />
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The basic mathematical model for a communication system is the following:<br />
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The basic mathematical model for a communication system is the following:<br />
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通信系统的基本数学模型如下:<br />
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[[File:Channel model.svg|center|800px|Channel model]]<br />
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Channel model<br />
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通道模型<br />
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A '''message''' ''W'' is transmitted through a noisy channel by using encoding and decoding functions. An '''encoder''' maps ''W'' into a pre-defined sequence of channel symbols of length ''n''. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a '''decoder''' which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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A message W is transmitted through a noisy channel by using encoding and decoding functions. An encoder maps W into a pre-defined sequence of channel symbols of length n. In its most basic model, the channel distorts each of these symbols independently of the others. The output of the channel –the received sequence– is fed into a decoder which maps the sequence into an estimate of the message. In this setting, the probability of error is defined as:<br />
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通过使用编码和解码函数,信息 w 通过噪声信道传输。编码器将 w 映射到预先定义的长度为 n 的信道符号序列。在其最基本的模型中,信道对这些符号的扭曲是独立于其他符号的。信道的输出——接收序列——被送入解码器,解码器将序列映射到消息的估计值中。在这种情况下,错误的概率定义为:<br />
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::<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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<math> P_e = \text{Pr}\left\{ \hat{W} \neq W \right\}. </math><br />
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[数学 > p _ e = 文本{ Pr }左{ w } neq w 右}。数学<br />
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'''Theorem''' (Shannon, 1948):<br />
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Theorem (Shannon, 1948):<br />
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定理(Shannon,1948) :<br />
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:1. For every discrete memoryless channel, the [[channel capacity]] is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1. For every discrete memoryless channel, the channel capacity is defined in terms of the mutual information <math>I(X; Y)</math>,<br />
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1.对于每一个离散的无记忆信道,信道容量是根据互信息 i (x; y) </math > 来定义的,<br />
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::<math>\ C = \sup_{p_X} I(X;Y)</math><ref>For a description of the "sup" function, see [[Supremum]]</ref><br />
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<math>\ C = \sup_{p_X} I(X;Y)</math><br />
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[ math > c = sup { p _ x } i (x; y) </math ]<br />
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:has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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has the following property. For any <math>\epsilon>0</math> and <math>R<C</math>, for large enough <math>N</math>, there exists a code of length <math>N</math> and rate <math>\geq R</math> and a decoding algorithm, such that the maximal probability of block error is <math>\leq \epsilon</math>.<br />
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具有以下属性。对于任何 < math > epsilon > 0 </math > 和 < math > r < c </math > ,对于足够大的 < math > n </math > ,存在一个长度为 < math > n </math > 和速率 < math > geq r </math > 的代码和一个解码算法,使得块错误的最大概率为 < math > leq epq </math > 。<br />
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:2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2. If a probability of bit error <math>p_b</math> is acceptable, rates up to <math>R(p_b)</math> are achievable, where<br />
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2.如果位错概率 < math > p _ b </math > 是可以接受的,那么达到 < math > r (p _ b) </math > 的速率是可以实现的<br />
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::<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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<math>R(p_b) = \frac{C}{1-H_2(p_b)} .</math><br />
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1-H _ 2(p _ b)} . </math > <br />
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:and <math> H_2(p_b)</math> is the ''[[binary entropy function]]''<br />
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and <math> H_2(p_b)</math> is the binary entropy function<br />
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2(p _ b) </math > 是二元熵函数<br />
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::<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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<math>H_2(p_b)=- \left[ p_b \log_2 {p_b} + (1-p_b) \log_2 ({1-p_b}) \right]</math><br />
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< math > h _ 2(p _ b) =-左[ p _ b log_2{ p _ b } + (1-p _ b) log_2({1-p _ b })右] </math > <br />
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:3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3. For any <math>p_b</math>, rates greater than <math>R(p_b)</math> are not achievable.<br />
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3.对于任何 < math > p _ b </math > ,比率大于 < math > r (p _ b) </math > 是无法实现的。<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003), p.&nbsp;162; cf Gallager (1968), ch.5; Cover and Thomas (1991), p.&nbsp;198; Shannon (1948) thm. 11)<br />
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(MacKay (2003) ,第162页; cf Gallager (1968) ,第5章; Cover and Thomas (1991) ,第198页; Shannon (1948) thm。11)<br />
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== Outline of proof ==<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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As with the several other major results in information theory, the proof of the noisy channel coding theorem includes an achievability result and a matching converse result. These two components serve to bound, in this case, the set of possible rates at which one can communicate over a noisy channel, and matching serves to show that these bounds are tight bounds.<br />
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与信息论中的其他几个主要结果一样,噪声信道编码定理的证明包括可实现性结果和匹配逆向结果。在这种情况下,这两个组件用于绑定人们可以在噪声信道上进行通信的可能速率集,而匹配则用于表明这些边界是紧边界。<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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The following outlines are only one set of many different styles available for study in information theory texts.<br />
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下面的提纲只是信息论课本中许多不同文体中的一种。<br />
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===Achievability for discrete memoryless channels===<br />
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This particular proof of achievability follows the style of proofs that make use of the [[asymptotic equipartition property]] (AEP). Another style can be found in information theory texts using [[error exponent]]s.<br />
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This particular proof of achievability follows the style of proofs that make use of the asymptotic equipartition property (AEP). Another style can be found in information theory texts using error exponents.<br />
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这个关于可达成性的特殊证明遵循了使用美国渐近等同分割特性协会(AEP)的证明的风格。另一种风格可以在信息论文本中找到,使用错误指数。<br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the [[channel capacity]].<br />
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Both types of proofs make use of a random coding argument where the codebook used across a channel is randomly constructed - this serves to make the analysis simpler while still proving the existence of a code satisfying a desired low probability of error at any data rate below the channel capacity.<br />
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这两种证明都使用了随机编码参数,其中跨信道使用的码本是随机构造的——这有助于使分析更简单,同时仍然证明在低于信道容量的任何数据速率下,满足所需的低错误概率的代码的存在。<br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a ''jointly typical set'' by the following:<br />
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By an AEP-related argument, given a channel, length <math>n</math> strings of source symbols <math>X_1^{n}</math>, and length <math>n</math> strings of channel outputs <math>Y_1^{n}</math>, we can define a jointly typical set by the following:<br />
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通过一个与 aep-相关的参数,给定一个通道,长度 < math > n </math > 源符号的字符串 < math > x _ 1 ^ { n } </math > ,以及长度 < math > n </math > n </math > 通道输出的字符串 < math > y _ 1 ^ { n } </math > ,我们可以定义一个联合的典型集合如下:<br />
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: <math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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<math>A_\varepsilon^{(n)} = \{(x^n, y^n) \in \mathcal X^n \times \mathcal Y^n </math><br />
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数学 x ^ n 乘以数学 y ^ n </math > <br />
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:::<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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<math>2^{-n(H(X)+\varepsilon)} \le p(X_1^n) \le 2^{-n(H(X) - \varepsilon)}</math><br />
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2 ^ {-n (h (x) + varepsilon)} le p (x _ 1 ^ n) le 2 ^ {-n (h (x)-varepsilon)} </math > <br />
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:::<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
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<math>2^{-n(H(Y) + \varepsilon)} \le p(Y_1^n) \le 2^{-n(H(Y)-\varepsilon)}</math><br />
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2 ^ {-n (h (y) + varepsilon)} le p (y _ 1 ^ n) le 2 ^ {-n (h (y)-varepsilon)}<br />
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:::<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
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<math>{2^{-n(H(X,Y) + \varepsilon)}}\le p(X_1^n, Y_1^n) \le 2^{-n(H(X,Y) -\varepsilon)} \}</math><br />
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{2 ^ {-n (h (x,y) + varepsilon)} le p (x _ 1 ^ n,y _ 1 ^ n) le 2 ^ {-n (h (x,y)-varepsilon)}<br />
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We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are ''jointly typical'' if they lie in the jointly typical set defined above.<br />
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We say that two sequences <math>{X_1^n}</math> and <math>Y_1^n</math> are jointly typical if they lie in the jointly typical set defined above.<br />
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我们说两个序列 < math > { x1 ^ n } </math > 和 < math > y _ 1 ^ n </math > 如果它们位于上面定义的联合典型集合中,那么它们是共同典型的。<br />
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'''Steps'''<br />
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Steps<br />
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步骤<br />
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#In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
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In the style of the random coding argument, we randomly generate <math> 2^{nR} </math> codewords of length n from a probability distribution Q.<br />
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在随机编码参数的风格中,我们随机从概率分布 q 生成长度为 n 的长度为2 ^ { nR } </math > 的码字。<br />
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#This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
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This code is revealed to the sender and receiver. It is also assumed that one knows the transition matrix <math>p(y|x)</math> for the channel being used.<br />
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这段代码向发送者和接收者显示。还假设人们知道所使用的通道的转移矩阵。<br />
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#A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
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A message W is chosen according to the uniform distribution on the set of codewords. That is, <math>Pr(W = w) = 2^{-nR}, w = 1, 2, \dots, 2^{nR}</math>.<br />
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根据码字集上的均匀分布选择消息 w。也就是,< math > Pr (w = w) = 2 ^ {-nR } ,w = 1,2,dots,2 ^ { nR } </math > 。<br />
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#The message W is sent across the channel.<br />
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The message W is sent across the channel.<br />
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消息 w 是通过通道发送的。<br />
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#The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
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The receiver receives a sequence according to <math>P(y^n|x^n(w))= \prod_{i = 1}^np(y_i|x_i(w))</math><br />
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接收端根据 < math > p (y ^ n | x ^ n (w)) = prod _ { i = 1} ^ np (y _ i | x _ i (w)) </math > 接收一个序列<br />
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#Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called ''typical set decoding''.<br />
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Sending these codewords across the channel, we receive <math>Y_1^n</math>, and decode to some source sequence if there exists exactly 1 codeword that is jointly typical with Y. If there are no jointly typical codewords, or if there are more than one, an error is declared. An error also occurs if a decoded codeword doesn't match the original codeword. This is called typical set decoding.<br />
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通过信道发送这些码字,我们接收到 y _ (1 ^ n) </math > ,并解码到某个源序列,如果存在正好与 y 共同典型的一个码字。如果没有共同的典型代码字,或者有多个代码字,则声明错误。如果解码的码字与原始码字不匹配,也会发生错误。这就是所谓的典型集合译码。<br />
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The probability of error of this scheme is divided into two parts:<br />
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The probability of error of this scheme is divided into two parts:<br />
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该方案的误差概率分为两部分:<br />
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#First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
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First, error can occur if no jointly typical X sequences are found for a received Y sequence<br />
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首先,如果没有为接收到的 y 序列找到联合的典型 x 序列,就可能发生错误<br />
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#Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
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Second, error can occur if an incorrect X sequence is jointly typical with a received Y sequence.<br />
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其次,如果一个不正确的 x 序列与一个接收到的 y 序列是共同的典型,则可能发生错误。<br />
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*By the randomness of the code construction, we can assume that the average probability of error averaged over all codes does not depend on the index sent. Thus, without loss of generality, we can assume ''W'' = 1.<br />
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*From the joint AEP, we know that the probability that no jointly typical X exists goes to 0 as n grows large. We can bound this error probability by <math>\varepsilon</math>.<br />
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*Also from the joint AEP, we know the probability that a particular <math>X_1^{n}(i)</math> and the <math>Y_1^n</math> resulting from ''W'' = 1 are jointly typical is <math>\le 2^{-n(I(X;Y) - 3\varepsilon)}</math>.<br />
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Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
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Define: <math>E_i = \{(X_1^n(i), Y_1^n) \in A_\varepsilon^{(n)}\}, i = 1, 2, \dots, 2^{nR}</math><br />
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定义: < math > e _ i = {(x _ 1 ^ n (i) ,y _ 1 ^ n) in a _ varepsilon ^ {(n)}} ,i = 1,2,dots,2 ^ { nR } </math > <br />
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as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
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as the event that message i is jointly typical with the sequence received when message 1 is sent.<br />
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作为消息 i 与消息1发送时接收到的序列一起发生的典型事件。<br />
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: <math><br />
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<math><br />
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《数学》<br />
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\begin{align}<br />
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\begin{align}<br />
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开始{ align }<br />
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P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
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P(\text{error}) & {} = P(\text{error}|W=1) \le P(E_1^c) + \sum_{i=2}^{2^{nR}}P(E_i) \\<br />
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P (text { error }) & {} = p (text { error } | w = 1) le p (e_1 ^ c) + sum _ { i = 2} ^ {2 ^ { nR }} p (e_i)<br />
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& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
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& {} \le P(E_1^c) + (2^{nR}-1)2^{-n(I(X;Y)-3\varepsilon)} \\<br />
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& {} le p (e _ 1 ^ c) + (2 ^ { nR }-1)2 ^ {-n (i (x; y)-3 varepsilon)}<br />
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& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
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& {} \le \varepsilon + 2^{-n(I(X;Y)-R-3\varepsilon)}.<br />
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& {} le varepsilon + 2 ^ {-n (i (x; y)-R-3 varepsilon)}.<br />
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\end{align}<br />
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\end{align}<br />
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结束{ align }<br />
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</math><br />
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</math><br />
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数学<br />
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We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
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We can observe that as <math>n</math> goes to infinity, if <math>R < I(X;Y)</math> for the channel, the probability of error will go to 0.<br />
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我们可以观察到,当 < math > n </math > 趋于无穷大时,如果 < math > r < i (x; y) </math > 对于通道,错误概率将趋于0。<br />
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Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
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Finally, given that the average codebook is shown to be "good," we know that there exists a codebook whose performance is better than the average, and so satisfies our need for arbitrarily low error probability communicating across the noisy channel.<br />
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最后,假设平均码本是“好的” ,我们知道存在一个性能优于平均值的码本,从而满足了我们在噪声信道中任意低错误概率通信的需要。<br />
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=== Weak converse for discrete memoryless channels===<br />
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Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
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Suppose a code of <math>2^{nR}</math> codewords. Let W be drawn uniformly over this set as an index. Let <math>X^n</math> and <math>Y^n</math> be the transmitted codewords and received codewords, respectively.<br />
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假设一个 < math > 2 ^ { nR } </math > 代码字的代码。让 w 作为索引均匀地绘制在这个集合上。让 < math > x ^ n </math > 和 < math > y ^ n </math > 分别作为传输代码和接收代码。<br />
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#<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and [[mutual information]]<br />
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<math>nR = H(W) = H(W|Y^n) + I(W;Y^n)</math> using identities involving entropy and mutual information<br />
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使用包含熵和互信息的恒等式 < math > nR = h (w) = h (w | y ^ n) + i (w; y ^ n) </math<br />
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#<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
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<math>\le H(W|Y^n) + I(X^n(W);Y^{n})</math> since X is a function of W<br />
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因为 x 是 w 的一个函数,所以它是一个数学公式<br />
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#<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of [[Fano's Inequality]]<br />
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<math>\le 1 + P_e^{(n)}nR + I(X^n(W);Y^n)</math> by the use of Fano's Inequality<br />
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利用 Fano 不等式,得到了一个新的数学公式: (1 + p _ e ^ {(n)} nR + i (x ^ n (w) ; y ^ n) </math<br />
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#<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
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<math>\le 1 + P_e^{(n)}nR + nC</math> by the fact that capacity is maximized mutual information.<br />
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由于容量是最大化的互信息,因此[ math > le 1 + p _ e ^ {(n)} nR + nC。<br />
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The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
<br />
The result of these steps is that <math> P_e^{(n)} \ge 1 - \frac{1}{nR} - \frac{C}{R} </math>. As the block length <math>n</math> goes to infinity, we obtain <math> P_e^{(n)}</math> is bounded away from 0 if R is greater than C - we can get arbitrarily low rates of error only if R is less than C.<br />
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这些步骤的结果是 < math > p _ e ^ {(n)} ge 1-frac {1}{ nR }-frac { c }{ r }{ math > 。当块长度 < math > n </math > 趋于无穷大时,我们得到当 r 大于 c 时 < math > p _ e ^ {(n)} </math > 远离0,我们只有当 r 小于 c 时才能得到任意低的误差率。<br />
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=== Strong converse for discrete memoryless channels ===<br />
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A strong converse theorem, proven by Wolfowitz in 1957,<ref>Robert Gallager. ''Information Theory and Reliable Communication.'' New York: [[John Wiley & Sons]], 1968. {{ISBN|0-471-29048-3}}</ref> states that,<br />
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A strong converse theorem, proven by Wolfowitz in 1957, states that,<br />
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沃尔福威茨在1957年证明了一个强逆定理,<br />
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:<math><br />
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<math><br />
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《数学》<br />
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P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
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P_e \geq 1- \frac{4A}{n(R-C)^2} - e^{-\frac{n(R-C)}{2}}<br />
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P _ e geq 1-frac {4A }{ n (R-C) ^ 2}-e ^ {-frac { n (R-C)}{2}<br />
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</math><br />
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</math><br />
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数学<br />
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<br />
for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
<br />
for some finite positive constant <math>A</math>. While the weak converse states that the error probability is bounded away from zero as <math>n</math> goes to infinity, the strong converse states that the error goes to 1. Thus, <math>C</math> is a sharp threshold between perfectly reliable and completely unreliable communication.<br />
<br />
为了某个有限的正常数。当弱逆表示错误概率远离零是有界的时候,强逆表示错误概率远离零是有界的。因此,c </math > 是完全可靠和完全不可靠的通信之间的一个尖锐的门槛。<br />
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<br />
<br />
== Channel coding theorem for non-stationary memoryless channels==<br />
<br />
We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
<br />
We assume that the channel is memoryless, but its transition probabilities change with time, in a fashion known at the transmitter as well as the receiver.<br />
<br />
我们假设信道是无记忆的,但是它的跃迁概率随时间而变化,这种变化在发射机和接收机中都是已知的。<br />
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<br />
<br />
Then the channel capacity is given by<br />
<br />
Then the channel capacity is given by<br />
<br />
然后通过对信道容量的分析,给出信道容量的计算公式<br />
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<br />
<br />
:<math> <br />
<br />
<math> <br />
<br />
《数学》<br />
<br />
C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
<br />
C=\lim \inf \max_{p^{(X_1)},p^{(X_2)},...}\frac{1}{n}\sum_{i=1}^nI(X_i;Y_i).<br />
<br />
C = lim inf max { p ^ {(x _ 1)} ,p ^ {(x _ 2)} ,... } frac {1}{ n } sum { i = 1} ^ nI (x _ i; y _ i).<br />
<br />
</math><br />
<br />
</math><br />
<br />
数学<br />
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<br />
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The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
<br />
The maximum is attained at the capacity achieving distributions for each respective channel. That is,<br />
<br />
在每个通道的容量分配上达到最大值。就是,<br />
<br />
<math><br />
<br />
<math><br />
<br />
《数学》<br />
<br />
C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
<br />
C=\lim \inf \frac{1}{n}\sum_{i=1}^n C_i<br />
<br />
1}{ n } sum { i = 1} ^ n c _ i<br />
<br />
</math><br />
<br />
</math><br />
<br />
数学<br />
<br />
where <math>C_i</math> is the capacity of the i''th'' channel.<br />
<br />
where <math>C_i</math> is the capacity of the ith channel.<br />
<br />
其中 c _ i </math > 是第 i 通道的容量。<br />
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<br />
<br />
=== Outline of the proof===<br />
<br />
The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the [[asymptotic equipartition property]] article.<br />
<br />
The proof runs through in almost the same way as that of channel coding theorem. Achievability follows from random coding with each symbol chosen randomly from the capacity achieving distribution for that particular channel. Typicality arguments use the definition of typical sets for non-stationary sources defined in the asymptotic equipartition property article.<br />
<br />
证明过程与信道编码定理的证明过程几乎一样。可实现性遵循从特定信道的容量实现分布中随机选择每个符号的随机编码。典型论证使用的定义,典型集定义为非平稳的来源定义在渐近等同分割特性文章。<br />
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<br />
<br />
The technicality of [[lim inf]] comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
<br />
The technicality of lim inf comes into play when <math>\frac{1}{n}\sum_{i=1}^n C_i</math> does not converge.<br />
<br />
当[ math ]{ n } sum { i = 1} ^ n c _ i </math > 不收敛时,lim inf 的技术性就发挥了作用。<br />
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==See also==<br />
<br />
* [[Asymptotic equipartition property]] (AEP)<br />
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* [[Fano's inequality]]<br />
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* [[Rate–distortion theory]]<br />
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* [[Shannon's source coding theorem]]<br />
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* [[Shannon–Hartley theorem]]<br />
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* [[Turbo code]]<br />
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==Notes==<br />
<br />
{{reflist}}<br />
<br />
<br />
<br />
==References==<br />
<br />
* [[Thomas M. Cover|Cover T. M.]], Thomas J. A., ''Elements of Information Theory'', [[John Wiley & Sons]], 1991. {{ISBN|0-471-06259-6}}<br />
<br />
*[[Fano|Fano, R. A.]], ''Transmission of information; a statistical theory of communications'', [[MIT Press]], 1961. {{ISBN|0-262-06001-9}}<br />
<br />
*[[Amiel Feinstein|Feinstein, Amiel]], "A New basic theorem of information theory", ''[[IEEE Transactions on Information Theory]]'', 4(4): 2-22, 1954.<br />
<br />
* [[David J.C. MacKay|MacKay, David J. C.]], ''[http://www.inference.phy.cam.ac.uk/mackay/itila/book.html Information Theory, Inference, and Learning Algorithms]'', [[Cambridge University Press]], 2003. {{ISBN|0-521-64298-1}} [free online]<br />
<br />
*[[Claude E. Shannon|Shannon, C. E.]], [https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6773024 ''A Mathematical Theory of Communication'']. ''The Bell System Technical Journal'' 27,3: 379–423, 1948.<br />
<br />
*[[Claude E. Shannon|Shannon, C. E.]], [http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html ''A Mathematical Theory of Communication''] Urbana, IL: University of Illinois Press, 1948 (reprinted 1998).<br />
<br />
*[[Wolfowitz| Wolfowitz, J.]], "[https://projecteuclid.org/download/pdf_1/euclid.ijm/1255380682 The coding of messages subject to chance errors]", ''Illinois J. Math.'', 1: 591–606, 1957.<br />
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==External links==<br />
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* [http://www.cs.miami.edu/home/burt/learning/Csc524.142/LarsTelektronikk02.pdf On Shannon and Shannon's law]<br />
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* [http://cnx.org/content/m10180/latest/ Shannon's Noisy Channel Coding Theorem]<br />
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{{DEFAULTSORT:Noisy-Channel Coding Theorem}}<br />
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[[Category:Information theory]]<br />
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Category:Information theory<br />
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范畴: 信息论<br />
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[[Category:Theorems in discrete mathematics]]<br />
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Category:Theorems in discrete mathematics<br />
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范畴: 离散数学的定理<br />
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[[Category:Telecommunication theory]]<br />
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Category:Telecommunication theory<br />
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范畴: 电信理论<br />
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[[Category:Coding theory]]<br />
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Category:Coding theory<br />
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类别: 编码理论<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Noisy-channel coding theorem]]. Its edit history can be viewed at [[有噪信道编码定理/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%BC%94%E5%8C%96%E8%AE%A1%E7%AE%97&diff=19568演化计算2020-12-01T04:54:16Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译。<br />
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In [[computer science]], '''evolutionary computation''' is a family of [[algorithm]]s for [[global optimization]] inspired by [[biological evolution]], and the subfield of [[artificial intelligence]] and [[soft computing]] studying these algorithms. In technical terms, they are a family of population-based [[trial and error]] problem solvers with a [[metaheuristic]] or [[stochastic optimization]] character.<br />
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In computer science, evolutionary computation is a family of algorithms for global optimization inspired by biological evolution, and the subfield of artificial intelligence and soft computing studying these algorithms. In technical terms, they are a family of population-based trial and error problem solvers with a metaheuristic or stochastic optimization character.<br />
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在计算机科学中,<font color="#ff8000"> 演化计算 Evolutionary computation</font>是一个受生物进化启发的全局优化算法家族,人工智能和软计算的子领域研究这些算法。在技术术语上,它们是一个基于群体的试错问题求解器家族,具有元启发式或随机优化特性。<br />
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In evolutionary computation, an initial set of candidate solutions is generated and iteratively updated. Each new generation is produced by stochastically removing less desired solutions, and introducing small random changes. In biological terminology, a [[population]] of solutions is subjected to [[natural selection]] (or [[artificial selection]]) and [[mutation]]. As a result, the population will gradually [[evolution|evolve]] to increase in [[fitness (biology)|fitness]], in this case the chosen [[fitness function]] of the algorithm.<br />
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In evolutionary computation, an initial set of candidate solutions is generated and iteratively updated. Each new generation is produced by stochastically removing less desired solutions, and introducing small random changes. In biological terminology, a population of solutions is subjected to natural selection (or artificial selection) and mutation. As a result, the population will gradually evolve to increase in fitness, in this case the chosen fitness function of the algorithm.<br />
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在演化计算中,一个初始的候选解决方案集被生成并迭代更新。每一代都是通过随机去除不太理想的解法,引入小的随机变化而产生的。在生物学术语中,一个解决方案的群体经历自然选择(或人工选择)和突变。因此,种群会逐渐演化为适应度增加,在这种情况下选择适应度函数的算法。 <br />
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Evolutionary computation techniques can produce highly optimized solutions in a wide range of problem settings, making them popular in [[computer science]]. Many variants and extensions exist, suited to more specific families of problems and data structures. Evolutionary computation is also sometimes used in [[evolutionary biology]] as an ''in silico'' experimental procedure to study common aspects of general evolutionary processes.<br />
<br />
Evolutionary computation techniques can produce highly optimized solutions in a wide range of problem settings, making them popular in computer science. Many variants and extensions exist, suited to more specific families of problems and data structures. Evolutionary computation is also sometimes used in evolutionary biology as an in silico experimental procedure to study common aspects of general evolutionary processes.<br />
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演化计算技术可以在广泛的问题设置中产生高度优化的解决方案,使其在计算机科学中广受欢迎。演化计算存在许多变体和扩展,能适用于更具体的问题族和数据结构。演化计算有时也被用在演化生物学中,作为一种电子实验程序来研究一般演化过程的共同方面。<br />
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== History ==<br />
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== History ==<br />
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历史<br />
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The use of evolutionary principles for automated problem solving originated in the 1950s. It was not until the 1960s that three distinct interpretations of this idea started to be developed in three different places.<br />
<br />
The use of evolutionary principles for automated problem solving originated in the 1950s. It was not until the 1960s that three distinct interpretations of this idea started to be developed in three different places.<br />
<br />
自动化问题解决的演化原理的使用起源于20世纪50年代。直到20世纪60年代,才在三个不同的地方形成了对这一观点的三种不同的解释。<br />
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''[[Evolutionary programming]]'' was introduced by [[Lawrence J. Fogel]] in the US, while [[John Henry Holland]] called his method a ''[[genetic algorithm]]''. In Germany [[Ingo Rechenberg]] and [[Hans-Paul Schwefel]] introduced ''[[Evolution strategy|evolution strategies]]''. These areas developed separately for about 15 years. From the early nineties on they are unified as different representatives ("dialects") of one technology, called ''evolutionary computing''. Also in the early nineties, a fourth stream following the general ideas had emerged – ''[[genetic programming]]''. Since the 1990s, nature-inspired algorithms are becoming an increasingly significant part of the evolutionary computation.<br />
<br />
Evolutionary programming was introduced by Lawrence J. Fogel in the US, while John Henry Holland called his method a genetic algorithm. In Germany Ingo Rechenberg and Hans-Paul Schwefel introduced evolution strategies. These areas developed separately for about 15 years. From the early nineties on they are unified as different representatives ("dialects") of one technology, called evolutionary computing. Also in the early nineties, a fourth stream following the general ideas had emerged – genetic programming. Since the 1990s, nature-inspired algorithms are becoming an increasingly significant part of the evolutionary computation.<br />
<br />
演化规划是由美国的 Lawrence J. Foge提出的,而 John Henry Holland称他的方法为遗传算法。在德国,Ingo Rechenberg 和 Hans-Paul Schwefel 引入了演化策略。这些地区分别发展了大约15年。从九十年代早期开始,它们被统一为一种被称为演化计算的技术的不同代表(类似“方言”)。也是在九十年代初期,出现了继一般思想之后的第四种思潮——遗传程序设计。自20世纪90年代以来,以自然为灵感的算法正在成为日益重要的演化计算。<br />
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These terminologies denote the field of evolutionary computing and consider evolutionary programming, evolution strategies, genetic algorithms, and genetic programming as sub-areas.<br />
<br />
These terminologies denote the field of evolutionary computing and consider evolutionary programming, evolution strategies, genetic algorithms, and genetic programming as sub-areas.<br />
<br />
这些术语表示演化计算领域,并将演化规划、演化策略、遗传算法和遗传规划作为子领域。<br />
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Simulations of [[evolution]] using [[evolutionary algorithm]]s and [[artificial life]] started with the work of Nils Aall Barricelli in the 1960s, and was extended by [[Alex Fraser (scientist)|Alex Fraser]], who published a series of papers on simulation of [[artificial selection]].<ref>{{cite journal |author=Fraser AS |title=Monte Carlo analyses of genetic models |journal=Nature |volume=181 |issue=4603 |pages=208–9 |year=1958 |pmid=13504138 |doi=10.1038/181208a0 |ref=harv|bibcode=1958Natur.181..208F }}</ref> [[Evolutionary algorithm|Artificial evolution]] became a widely recognised optimisation method as a result of the work of [[Ingo Rechenberg]] in the 1960s and early 1970s, who used [[Evolution strategy|evolution strategies]] to solve complex engineering problems.<ref>{{cite book |last=Rechenberg |first=Ingo |year=1973 |title=Evolutionsstrategie&nbsp;– Optimierung technischer Systeme nach Prinzipien der biologischen Evolution (PhD thesis) |publisher=Fromman-Holzboog|language = German}}</ref> [[Genetic algorithm]]s in particular became popular through the writing of [[John Henry Holland|John Holland]].<ref>{{cite book |last=Holland |first=John H. |year=1975 |title=Adaptation in Natural and Artificial Systems |publisher=[[University of Michigan Press]] |isbn=978-0-262-58111-0 |url-access=registration |url=https://archive.org/details/adaptationinnatu00holl }}</ref> As academic interest grew, dramatic increases in the power of computers allowed practical applications, including the automatic evolution of computer programs.<ref>{{cite book |last=Koza|first=John R. |year=1992 |title=Genetic Programming: On the Programming of Computers by Means of Natural Selection|publisher=[[MIT Press]] |isbn=978-0-262-11170-6}}</ref> Evolutionary algorithms are now used to solve multi-dimensional problems more efficiently than software produced by human designers, and also to optimise the design of systems.<ref>G. C. Onwubolu and B V Babu, {{cite book|url=https://www.springer.com/in/book/9783540201670|title=New Optimization Techniques in Engineering|accessdate=17 September 2016|isbn=9783540201670|last1=Onwubolu|first1=Godfrey C.|last2=Babu|first2=B. V.|date=2004-01-21}}</ref><ref>{{cite journal |author=Jamshidi M |title=Tools for intelligent control: fuzzy controllers, neural networks and genetic algorithms |journal=[[Philosophical Transactions of the Royal Society A]] |volume=361 |issue=1809 |pages=1781–808 |year=2003 |pmid=12952685 |doi=10.1098/rsta.2003.1225 |ref=harv|bibcode=2003RSPTA.361.1781J }}</ref><br />
<br />
Simulations of evolution using evolutionary algorithms and artificial life started with the work of Nils Aall Barricelli in the 1960s, and was extended by Alex Fraser, who published a series of papers on simulation of artificial selection. Artificial evolution became a widely recognised optimisation method as a result of the work of Ingo Rechenberg in the 1960s and early 1970s, who used evolution strategies to solve complex engineering problems. Genetic algorithms in particular became popular through the writing of John Holland. As academic interest grew, dramatic increases in the power of computers allowed practical applications, including the automatic evolution of computer programs. Evolutionary algorithms are now used to solve multi-dimensional problems more efficiently than software produced by human designers, and also to optimise the design of systems.<br />
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利用演化算法和人工生命模拟进化始于20世纪60年代 Nils Aall Barricelli的工作,后来被Alex Fraser扩展,他发表了一系列关于人工选择模拟的论文。20世纪60年代和70年代早期,Ingo Rechenberg 使用演化策略解决复杂的工程问题,人工演化因此成为广泛认可的优化方法。尤其是通过约翰·霍兰德的著作,遗传算法变得流行起来。随着学术兴趣的增长,计算机能力的急剧增长使得这种算法可以实际应用起来,其中包括计算机程序的自动演化。演化算法现在被用来解决多维问题,比人类设计者生产的软件更有效,同时也可以优化系统的设计。 <br />
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== Techniques ==<br />
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== Techniques ==<br />
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== Techniques ==<br />
技术<br />
Evolutionary computing techniques mostly involve [[metaheuristic]] [[Mathematical optimization|optimization]] [[algorithm]]s. Broadly speaking, the field includes:<br />
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Evolutionary computing techniques mostly involve metaheuristic optimization algorithms. Broadly speaking, the field includes:<br />
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演化计算技术主要涉及元启发式优化算法。一般来说,这个领域包括:<br />
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*[[Ant colony optimization]]<br />
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蚁群算法<br />
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*[[Artificial immune system]]s<br />
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人工免疫系统<br />
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*[[Artificial life]] (also see [[digital organism]])<br />
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人工生命(参见电子生命)<br />
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*[[Cultural algorithm]]s<br />
文化算法<br />
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*[[Differential evolution]]<br />
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差分演化<br />
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*[[Dual-phase evolution]]<br />
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双相演化<br />
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*[[Estimation of distribution algorithm]]s<br />
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分布算法估计<br />
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*[[Evolutionary algorithm]]s<br />
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演化算法<br />
*[[Evolutionary programming]]<br />
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演化编程<br />
*[[Evolution strategy]]<br />
演化策略<br />
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*[[Gene expression programming]]<br />
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基因表达式编程算法<br />
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*[[Genetic algorithm]]<br />
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基因算法<br />
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*[[Genetic programming]]<br />
基因编程<br />
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*[[Grammatical evolution]]<br />
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文法演化<br />
*[[Learnable evolution model]]<br />
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可学习演化模型<br />
*[[Learning classifier system]]s<br />
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学习分类系统<br />
*[[Memetic algorithms]]<br />
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遗传算法<br />
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*[[Neuroevolution]]<br />
神经进化<br />
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*[[Particle swarm optimization]]<br />
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粒子群优化算法<br />
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*[[Synergistic Fibroblast Optimization]]<br />
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协作成纤维细胞优化<br />
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*[[Self-organization]] such as [[self-organizing map]]s, [[competitive learning]]<br />
自我管理(例如自组织特征映射模型 竞争性学习)<br />
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*[[Swarm intelligence]]<br />
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集群智能<br />
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== Evolutionary algorithms ==<br />
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== Evolutionary algorithms ==<br />
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演化算法<br />
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{{Main|Evolutionary algorithm}}<br />
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[[Evolutionary algorithms]] form a subset of evolutionary computation in that they generally only involve techniques implementing mechanisms inspired by [[biological evolution]] such as [[reproduction]], [[mutation]], [[Genetic recombination|recombination]], [[natural selection]] and [[survival of the fittest]]. [[Candidate solutions]] to the optimization problem play the role of individuals in a population, and the [[Loss function|cost function]] determines the environment within which the solutions "live" (see also [[fitness function]]). [[Evolution]] of the population then takes place after the repeated application of the above operators.<br />
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Evolutionary algorithms form a subset of evolutionary computation in that they generally only involve techniques implementing mechanisms inspired by biological evolution such as reproduction, mutation, recombination, natural selection and survival of the fittest. Candidate solutions to the optimization problem play the role of individuals in a population, and the cost function determines the environment within which the solutions "live" (see also fitness function). Evolution of the population then takes place after the repeated application of the above operators.<br />
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演化算法是演化计算的一个子集,因为它们通常只涉及实现生物演化机制的技术,如繁殖、变异、重组、自然选择和适者生存。最佳化问题的候选解决方案扮演了人口中个体的角色,而成本函数决定了解决方案“生存”的环境(参见适应度函数)。在重复应用上述算子之后,种群的演化就发生了。<br />
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In this process, there are two main forces that form the basis of evolutionary systems: '''Recombination''' '''mutation''' and '''crossover''' create the necessary diversity and thereby facilitate novelty, while '''selection''' acts as a force increasing quality.<br />
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In this process, there are two main forces that form the basis of evolutionary systems: Recombination mutation and crossover create the necessary diversity and thereby facilitate novelty, while selection acts as a force increasing quality.<br />
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在这个过程中,有两种主要的力量构成了演化系统的基础: 重组变异和交叉创造了必要的多样性,从而促进了新颖性,而选择作为一种力来提高质量。<br />
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Many aspects of such an evolutionary process are [[stochastic]]. Changed pieces of information due to recombination and mutation are randomly chosen. On the other hand, selection operators can be either deterministic, or stochastic. In the latter case, individuals with a higher [[Fitness function|fitness]] have a higher chance to be selected than individuals with a lower [[Fitness function|fitness]], but typically even the weak individuals have a chance to become a parent or to survive.<br />
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Many aspects of such an evolutionary process are stochastic. Changed pieces of information due to recombination and mutation are randomly chosen. On the other hand, selection operators can be either deterministic, or stochastic. In the latter case, individuals with a higher fitness have a higher chance to be selected than individuals with a lower fitness, but typically even the weak individuals have a chance to become a parent or to survive.<br />
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这种演化过程的许多方面都是随机的。由于重组和突变而改变的信息片段是随机选择的。另一方面,选择运算符可以是确定性的,也可以是随机的。在后一种情况下,适合度较高的个体比适合度较低的个体有更高的机会被选中,但通常即使是体质较弱的个体也有机会成为父本或生存下来。<br />
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== Evolutionary algorithms and biology ==<br />
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== Evolutionary algorithms and biology ==<br />
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演化算法和生物学<br />
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{{Main|Evolutionary algorithm}}<br />
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[[Genetic algorithms]] deliver methods to model [[biological systems]] and [[systems biology]] that are linked to the theory of [[dynamical systems]], since they are used to predict the future states of the system. This is just a vivid (but perhaps misleading) way of drawing attention to the orderly, well-controlled and highly structured character of development in biology.<br />
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Genetic algorithms deliver methods to model biological systems and systems biology that are linked to the theory of dynamical systems, since they are used to predict the future states of the system. This is just a vivid (but perhaps misleading) way of drawing attention to the orderly, well-controlled and highly structured character of development in biology.<br />
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遗传算法提供了与动力系统理论相关的生物系统和系统生物学模型的方法,因为它们被用来预测系统的未来状态。这只是一种生动的(但也许是误导性的)方式,提醒人们注意生物学发展的有序、控制良好和高度结构化的特征。<br />
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However, the use of algorithms and informatics, in particular of [[computational theory]], beyond the analogy to dynamical systems, is also relevant to understand evolution itself.<br />
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However, the use of algorithms and informatics, in particular of computational theory, beyond the analogy to dynamical systems, is also relevant to understand evolution itself.<br />
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然而,算法和信息学的使用,特别是计算理论的使用,超越了对动力系统的类比,这也与理解演化本身有关。<br />
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This view has the merit of recognizing that there is no central control of development; organisms develop as a result of local interactions within and between cells. The most promising ideas about program-development parallels seem to us to be ones that point to an apparently close analogy between processes within cells, and the low-level operation of modern computers.<ref>{{Cite book | chapter-url=https://plato.stanford.edu/entries/information-biological/#InfEvo | title=The Stanford Encyclopedia of Philosophy| chapter=Biological Information| publisher=Metaphysics Research Lab, Stanford University| year=2016}}</ref> Thus, biological systems are like computational machines that process input information to compute next states, such that biological systems are closer to a computation than classical dynamical system.<ref>{{cite journal |author= J.G. Diaz Ochoa |title= Elastic Multi-scale Mechanisms: Computation and Biological Evolution |journal=[[Journal of Molecular Evolution]] |volume=86 |issue=1 |pages=47–57 |year=2018 |pmid=29248946 |doi=10.1007/s00239-017-9823-7 |ref=harv|bibcode=2018JMolE..86...47D }}</ref><br />
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This view has the merit of recognizing that there is no central control of development; organisms develop as a result of local interactions within and between cells. The most promising ideas about program-development parallels seem to us to be ones that point to an apparently close analogy between processes within cells, and the low-level operation of modern computers. Thus, biological systems are like computational machines that process input information to compute next states, such that biological systems are closer to a computation than classical dynamical system.<br />
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这一观点的优点是认识到没有发育的中央控制;生物体的发育是细胞内部和细胞之间局部相互作用的结果。在我们看来,关于程序开发并行的最有前途的想法似乎是那些指出细胞内的进程与现代计算机的低级操作之间明显相似的思想。因此,生物系统就像计算机器,处理输入信息来计算下一个状态,这样生物系统比经典的动力系统更接近于计算。<br />
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Furthermore, following concepts from [[computational theory]], micro processes in biological organisms are fundamentally incomplete and undecidable ([[completeness (logic)]]), implying that “there is more than a crude metaphor behind the analogy between cells and computers.<ref>{{cite journal |author= A. Danchin |title= Bacteria as computers making computers |journal=[[FEMS Microbiol. Rev.]] |volume=33 |issue=1 |pages=3–26 |year=2008 |doi=10.1111/j.1574-6976.2008.00137.x |pmid= 19016882 |ref=harv |pmc=2704931 }}</ref><br />
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Furthermore, following concepts from computational theory, micro processes in biological organisms are fundamentally incomplete and undecidable (completeness (logic)), implying that “there is more than a crude metaphor behind the analogy between cells and computers.<br />
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此外,根据计算理论的概念,生物有机体中的微进程从根本上来说是不完整的和不可判定的(完整性(逻辑)) ,这意味着细胞和计算机之间的类比背后不只是一个粗略的比喻。<br />
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The analogy to computation extends also to the relationship between [[inheritance systems]] and biological structure, which is often thought to reveal one of the most pressing problems in explaining the origins of life.<br />
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The analogy to computation extends also to the relationship between inheritance systems and biological structure, which is often thought to reveal one of the most pressing problems in explaining the origins of life.<br />
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计算的类比也延伸到遗传系统和生物结构之间的关系,这通常被认为是揭示解释生命起源最紧迫的问题之一。<br />
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''Evolutionary automata''{{r|ldr11|ldr13|ldr14}}, a generalization of ''Evolutionary Turing machines''{{r|ldr15|ldr16}}, have been introduced in order to investigate more precisely properties of biological and evolutionary computation. In particular, they allow to obtain new results on expressiveness of evolutionary computation{{r|ldr14|ldr17}}. This confirms the initial result about undecidability of natural evolution and evolutionary algorithms and processes. ''Evolutionary finite automata'', the simplest subclass of Evolutionary automata working in ''terminal mode'' can accept arbitrary languages over a given alphabet, including non-recursively enumerable (e.g., diagonalization language) and recursively enumerable but not recursive languages (e.g., language of the universal Turing machine){{r|ldr18}}. <br />
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Evolutionary automata, a generalization of Evolutionary Turing machines, have been introduced in order to investigate more precisely properties of biological and evolutionary computation. In particular, they allow to obtain new results on expressiveness of evolutionary computation. This confirms the initial result about undecidability of natural evolution and evolutionary algorithms and processes. Evolutionary finite automata, the simplest subclass of Evolutionary automata working in terminal mode can accept arbitrary languages over a given alphabet, including non-recursively enumerable (e.g., diagonalization language) and recursively enumerable but not recursive languages (e.g., language of the universal Turing machine). <br />
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演化自动机是演化图灵机<font color="#ff8000"> 图灵机Turing machines</font>的一种推广,为了更精确地研究生物和演化计算的性质,人们引入了它。特别是,他们允许在演化计算的表现力上获得新的结果。这证实了关于自然演化和演化算法及过程不可判定性的初步结果。演化有限自动机是演化自动机中最简单的子类,在终端模式下可以接受给定字母表上的任意语言,包括非递归的可枚举语言(例如,对角化语言)和递归的可枚举但不递归语言(例如,通用图灵机语言)。<br />
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== Notable practitioners ==<br />
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== Notable practitioners ==<br />
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著名从业人员<br />
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The list of active researchers is naturally dynamic and non-exhaustive. A network analysis of the community was published in 2007.<ref>{{cite arXiv |author=J.J. Merelo and C. Cotta |title=Who is the best connected EC researcher? Centrality analysis of the complex network of authors in evolutionary computation |year=2007 |eprint=0708.2021|class=cs.CY }}</ref><br />
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The list of active researchers is naturally dynamic and non-exhaustive. A network analysis of the community was published in 2007.<br />
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活跃的研究人员名单自然是动态的,并非详尽无遗。社区的网络分析在2007年发表。<br />
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* [[Kalyanmoy Deb]]<br />
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* [[Kenneth A De Jong]]<br />
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* [[Peter J. Fleming]]<br />
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* [[David B. Fogel]]<br />
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* [[Stephanie Forrest]]<br />
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* [[David E. Goldberg]]<br />
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* [[John Henry Holland]]<br />
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* [[Theo Jansen]]<br />
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* [[John Koza]]<br />
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* [[Zbigniew Michalewicz]]<br />
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* [[Melanie Mitchell]]<br />
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* [[Peter Nordin]]<br />
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* [[Riccardo Poli]]<br />
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* [[Ingo Rechenberg]]<br />
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* [[Hans-Paul Schwefel]]<br />
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== Conferences ==<br />
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== Conferences ==<br />
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会议<br />
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The main conferences in the evolutionary computation area include <br />
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The main conferences in the evolutionary computation area include <br />
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演化计算地区的主要会议包括<br />
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* [[Association for Computing Machinery|ACM]] [[Genetic and Evolutionary Computation Conference]] (GECCO), <br />
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计算机械协会 遗传与进化计算会议 <br />
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* [[IEEE Congress on Evolutionary Computation]] (CEC), <br />
IEEE演化计算大会<br />
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* [[EvoStar]], which comprises four conferences: EuroGP, EvoApplications, EvoCOP and EvoMUSART, <br />
EvoStar,包括四个会议:EuroGP、EvoApplications、EvoCOP和EvoMUSART,<br />
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* Parallel Problem Solving from Nature (PPSN).<br />
自然并行问题解决<br />
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== See also ==<br />
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== See also ==<br />
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参见<br />
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* [[Adaptive dimensional search]]<br />
适应性多维研究<br />
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* [[Artificial development]]<br />
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人工发展<br />
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* [[Autoconstructive]]<br />
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自动建设性<br />
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* [[Developmental biology]]<br />
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发展性生物学<br />
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* [[Digital organism]]<br />
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数字化生物<br />
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* [[Estimation of distribution algorithm]]<br />
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分布算法估计<br />
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* [[Evolutionary robotics]]<br />
演化机器人<br />
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* [[Evolved antenna]]<br />
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演化天线<br />
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* [[Fitness approximation]]<br />
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适应值近似<br />
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* [[Fitness function]]<br />
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适应值函数<br />
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* [[Fitness landscape]]<br />
适应度景观<br />
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* [[Genetic operators]]<br />
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遗传算子<br />
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* [[Grammatical evolution]]<br />
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文法演化<br />
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* [[Human-based evolutionary computation]]<br />
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人类演化计算<br />
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* [[Inferential programming]]<br />
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推断编程<br />
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* [[Interactive evolutionary computation]]<br />
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互动演化计算<br />
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* [[List of digital organism simulators]]<br />
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数字化有机体模拟器表<br />
* [[Mutation testing]]<br />
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变异测试<br />
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* [[No free lunch in search and optimization]]<br />
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研究和优化没有免费的午餐<br />
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* [[Program synthesis]]<br />
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程序综合<br />
* [[Test functions for optimization]]<br />
优化测试函数<br />
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* [[Universal Darwinism]]<br />
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普适达尔文主义<br />
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== External links ==<br />
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== External links ==<br />
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外部链接<br />
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*[https://plato.stanford.edu/entries/information-biological/#InfEvo/ Article in the Stanford Encyclopedia of Philosophy about Biological Information (English)]<br />
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== Bibliography ==<br />
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== Bibliography ==<br />
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参考书目<br />
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* Th. Bäck, D.B. Fogel, and [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.amazon.com/Handbook-Evolutionary-Computation-Thomas-Back/dp/0750303921 Handbook of Evolutionary Computation], 1997, {{ISBN|0750303921}}<br />
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* Th. Bäck and H.-P. Schwefel. [http://caribou.iisg.agh.edu.pl/pub/svn/age/jage/legacy/papers/mgrKA/pdf/evco.1993.1.1.pdf An overview of evolutionary algorithms for parameter optimization]. Evolutionary Computation, 1(1):1–23, 1993.<br />
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* W. Banzhaf, P. Nordin, R.E. Keller, and F.D. Francone. Genetic Programming — An Introduction. Morgan Kaufmann, 1998.<br />
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* S. Cagnoni, et al., [https://www.springer.com/computer+science/theoretical+computer+science/foundations+of+computations/book/978-3-540-67353-8 Real-World Applications of Evolutionary Computing], Springer-Verlag [[Lecture Notes in Computer Science]], Berlin, 2000.<br />
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* R. Chiong, Th. Weise, [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.springer.com/engineering/computational+intelligence+and+complexity/book/978-3-642-23423-1 Variants of Evolutionary Algorithms for Real-World Applications], [[Springer Publishing|Springer]], 2012, {{ISBN|3642234232}}<br />
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* K. A. De Jong, Evolutionary computation: a unified approach. [[MIT Press]], Cambridge MA, 2006<br />
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* {{cite journal |authors=A. E. Eiben and M. Schoenauer |title=Evolutionary computing|journal=Information Processing Letters|volume=82|pages=1–6|doi=10.1016/S0020-0190(02)00204-1|year=2002}}<br />
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* A. E. Eiben and J.E. Smith, [https://www.springer.com/computer/theoretical+computer+science/book/978-3-540-40184-1 Introduction to Evolutionary Computing], Springer, First edition, 2003, {{ISBN|3-540-40184-9}},<br />
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* D. B. Fogel. Evolutionary Computation. Toward a New Philosophy of Machine Intelligence. IEEE Press, Piscataway, NJ, 1995.<br />
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* L. J. Fogel, A. J. Owens, and M. J. Walsh. [[Artificial Intelligence]] through Simulated Evolution. New York: John Wiley, 1966.<br />
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* D. E. Goldberg. Genetic algorithms in search, optimization and machine learning. Addison Wesley, 1989.<br />
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* J. H. Holland. Adaptation in natural and artificial systems. [[University of Michigan Press]], Ann Arbor, 1975.<br />
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* P. Hingston, L. Barone, and [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.springer.com/computer/ai/book/978-3-540-74109-1 Design by Evolution, Natural Computing Series], 2008, [[Springer Publishing|Springer]], {{ISBN|3540741097}}<br />
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* J. R. Koza. Genetic Programming: On the Programming of Computers by means of Natural Evolution. MIT Press, Massachusetts, 1992.<br />
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* F.J. Lobo, C.F. Lima, [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.amazon.com/Parameter-Evolutionary-Algorithms-Computational-Intelligence/dp/3642088929/ Parameter Setting in Evolutionary Algorithms], [[Springer Publishing|Springer]], 2010, {{ISBN|3642088929}}<br />
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* [[Zbigniew Michalewicz|Z. Michalewicz]], [https://www.springer.com/computer/ai/book/978-3-540-60676-5 Genetic Algorithms + Data Structures – Evolution Programs], 1996, [[Springer Publishing|Springer]], {{ISBN|3540606769}}<br />
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* [[Zbigniew Michalewicz|Z. Michalewicz]] and D.B. Fogel, [https://www.springer.com/computer/theoretical+computer+science/book/978-3-540-22494-5 How to Solve It: Modern Heuristics], [[Springer Publishing|Springer]], 2004, {{ISBN|978-3-540-22494-5}}<br />
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* I. Rechenberg. Evolutionstrategie: Optimierung Technischer Systeme nach Prinzipien des Biologischen Evolution. Fromman-Hozlboog Verlag, Stuttgart, 1973. {{in lang|de}}<br />
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* H.-P. Schwefel. Numerical Optimization of Computer Models. John Wiley & Sons, New-York, 1981. 1995 – 2nd edition.<br />
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* D. Simon. [http://academic.csuohio.edu/simond/EvolutionaryOptimization Evolutionary Optimization Algorithms]. Wiley, 2013.<br />
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* {{cite journal |authors=M. Sipper, W. Fu, K. Ahuja, and J. H. Moore |title=Investigating the parameter space of evolutionary algorithms|journal=BioData Mining|volume=11|pages=2|doi=10.1186/s13040-018-0164-x|pmid=29467825|pmc=5816380|year=2018}}<br />
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* {{cite arxiv |authors=Y. Zhang and S. Li. |title=PSA: A novel optimization algorithm based on survival rules of porcellio scaber |eprint=1709.09840 |class=cs.NE |year=2017 }}<br />
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== References ==<br />
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== References ==<br />
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参考资料<br />
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{{reflist|refs=<br />
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{通货再膨胀 | 参考文献<br />
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<ref name="ldr11">{{Cite book |doi = 10.1007/978-3-642-29694-9_9|isbn = 978-3-642-29693-2|chapter = Recursively Generated Evolutionary Turing Machines and Evolutionary Automata |editor=Xin-She Yang |title = Artificial Intelligence, Evolutionary Computing and Metaheuristics|series = Studies in Computational Intelligence|year = 2013|last1 = Burgin|first1 = Mark|last2 = Eberbach|first2 = Eugene|volume = 427|pages = 201–230 |publisher=Springer-Verlag}}</ref><br />
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<ref name="ldr13">Burgin, M. and Eberbach, E. (2010) Bounded and Periodic Evolutionary Machines, in Proc. 2010 Congress on Evolutionary Computation (CEC'2010), Barcelona, Spain, 2010, pp. 1379-1386</ref><br />
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<ref name="ldr14">{{Cite journal |doi = 10.1093/comjnl/bxr099|title = Evolutionary Automata: Expressiveness and Convergence of Evolutionary Computation|year = 2012|last1 = Burgin|first1 = M.|last2 = Eberbach|first2 = E.|journal = The Computer Journal|volume = 55|issue = 9|pages = 1023–1029}}</ref><br />
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<ref name="ldr15">Eberbach E. (2002) On Expressiveness of Evolutionary Computation: Is EC Algorithmic?, Proc. 2002 World Congress on Computational Intelligence WCCI’2002, Honolulu, HI, 2002, 564-569.</ref><br />
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<ref name="ldr16">Eberbach, E. (2005) Toward a theory of evolutionary computation, BioSystems, v. 82, pp. 1-19.</ref><br />
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<ref name="ldr17">{{Cite book |doi = 10.1109/CEC.2009.4983207|isbn = 978-1-4244-2958-5|chapter = Evolutionary automata as foundation of evolutionary computation: Larry Fogel was right|title = 2009 IEEE Congress on Evolutionary Computation|year = 2009|last1 = Eberbach|first1 = Eugene|last2 = Burgin|first2 = Mark|pages = 2149–2156|publisher=IEEE}}</ref><br />
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<ref name="ldr18">Hopcroft, J.E., R. Motwani, and J.D. Ullman (2001) Introduction to Automata Theory, Languages, and Computation, Addison Wesley, Boston/San Francisco/New York</ref><br />
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<br />{{Evolutionary computation}}<br />
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[[Category:Evolutionary computation| ]]<br />
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[[Category:Evolution]]<br />
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Category:Evolution<br />
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分类: 进化<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Evolutionary computation]]. Its edit history can be viewed at [[演化计算/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%BC%94%E5%8C%96%E8%AE%A1%E7%AE%97&diff=19567演化计算2020-12-01T04:48:57Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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In [[computer science]], '''evolutionary computation''' is a family of [[algorithm]]s for [[global optimization]] inspired by [[biological evolution]], and the subfield of [[artificial intelligence]] and [[soft computing]] studying these algorithms. In technical terms, they are a family of population-based [[trial and error]] problem solvers with a [[metaheuristic]] or [[stochastic optimization]] character.<br />
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In computer science, evolutionary computation is a family of algorithms for global optimization inspired by biological evolution, and the subfield of artificial intelligence and soft computing studying these algorithms. In technical terms, they are a family of population-based trial and error problem solvers with a metaheuristic or stochastic optimization character.<br />
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在计算机科学中,<font color="#ff8000"> 演化计算 Evolutionary computation</font>是一个受生物进化启发的全局优化算法家族,人工智能和软计算的子领域研究这些算法。在技术术语上,它们是一个基于群体的试错问题求解器家族,具有元启发式或随机优化特性。<br />
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In evolutionary computation, an initial set of candidate solutions is generated and iteratively updated. Each new generation is produced by stochastically removing less desired solutions, and introducing small random changes. In biological terminology, a [[population]] of solutions is subjected to [[natural selection]] (or [[artificial selection]]) and [[mutation]]. As a result, the population will gradually [[evolution|evolve]] to increase in [[fitness (biology)|fitness]], in this case the chosen [[fitness function]] of the algorithm.<br />
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In evolutionary computation, an initial set of candidate solutions is generated and iteratively updated. Each new generation is produced by stochastically removing less desired solutions, and introducing small random changes. In biological terminology, a population of solutions is subjected to natural selection (or artificial selection) and mutation. As a result, the population will gradually evolve to increase in fitness, in this case the chosen fitness function of the algorithm.<br />
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在演化计算中,一个初始的候选解决方案集被生成并迭代更新。每一代都是通过随机去除不太理想的解法,引入小的随机变化而产生的。在生物学术语中,一个解决方案的群体经历自然选择(或人工选择)和突变。因此,种群会逐渐演化为适应度增加,在这种情况下选择适应度函数的算法。 <br />
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Evolutionary computation techniques can produce highly optimized solutions in a wide range of problem settings, making them popular in [[computer science]]. Many variants and extensions exist, suited to more specific families of problems and data structures. Evolutionary computation is also sometimes used in [[evolutionary biology]] as an ''in silico'' experimental procedure to study common aspects of general evolutionary processes.<br />
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Evolutionary computation techniques can produce highly optimized solutions in a wide range of problem settings, making them popular in computer science. Many variants and extensions exist, suited to more specific families of problems and data structures. Evolutionary computation is also sometimes used in evolutionary biology as an in silico experimental procedure to study common aspects of general evolutionary processes.<br />
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演化计算技术可以在广泛的问题设置中产生高度优化的解决方案,使其在计算机科学中广受欢迎。演化计算存在许多变体和扩展,能适用于更具体的问题族和数据结构。演化计算有时也被用在演化生物学中,作为一种电子实验程序来研究一般演化过程的共同方面。<br />
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== History ==<br />
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== History ==<br />
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历史<br />
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The use of evolutionary principles for automated problem solving originated in the 1950s. It was not until the 1960s that three distinct interpretations of this idea started to be developed in three different places.<br />
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The use of evolutionary principles for automated problem solving originated in the 1950s. It was not until the 1960s that three distinct interpretations of this idea started to be developed in three different places.<br />
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自动化问题解决的演化原理的使用起源于20世纪50年代。直到20世纪60年代,才在三个不同的地方形成了对这一观点的三种不同的解释。<br />
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''[[Evolutionary programming]]'' was introduced by [[Lawrence J. Fogel]] in the US, while [[John Henry Holland]] called his method a ''[[genetic algorithm]]''. In Germany [[Ingo Rechenberg]] and [[Hans-Paul Schwefel]] introduced ''[[Evolution strategy|evolution strategies]]''. These areas developed separately for about 15 years. From the early nineties on they are unified as different representatives ("dialects") of one technology, called ''evolutionary computing''. Also in the early nineties, a fourth stream following the general ideas had emerged – ''[[genetic programming]]''. Since the 1990s, nature-inspired algorithms are becoming an increasingly significant part of the evolutionary computation.<br />
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Evolutionary programming was introduced by Lawrence J. Fogel in the US, while John Henry Holland called his method a genetic algorithm. In Germany Ingo Rechenberg and Hans-Paul Schwefel introduced evolution strategies. These areas developed separately for about 15 years. From the early nineties on they are unified as different representatives ("dialects") of one technology, called evolutionary computing. Also in the early nineties, a fourth stream following the general ideas had emerged – genetic programming. Since the 1990s, nature-inspired algorithms are becoming an increasingly significant part of the evolutionary computation.<br />
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演化规划是由美国的 Lawrence J. Foge提出的,而 John Henry Holland称他的方法为遗传算法。在德国,Ingo Rechenberg 和 Hans-Paul Schwefel 引入了演化策略。这些地区分别发展了大约15年。从九十年代早期开始,它们被统一为一种被称为演化计算的技术的不同代表(类似“方言”)。也是在九十年代初期,出现了继一般思想之后的第四种思潮——遗传程序设计。自20世纪90年代以来,以自然为灵感的算法正在成为日益重要的演化计算。<br />
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These terminologies denote the field of evolutionary computing and consider evolutionary programming, evolution strategies, genetic algorithms, and genetic programming as sub-areas.<br />
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These terminologies denote the field of evolutionary computing and consider evolutionary programming, evolution strategies, genetic algorithms, and genetic programming as sub-areas.<br />
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这些术语表示演化计算领域,并将演化规划、演化策略、遗传算法和遗传规划作为子领域。<br />
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Simulations of [[evolution]] using [[evolutionary algorithm]]s and [[artificial life]] started with the work of Nils Aall Barricelli in the 1960s, and was extended by [[Alex Fraser (scientist)|Alex Fraser]], who published a series of papers on simulation of [[artificial selection]].<ref>{{cite journal |author=Fraser AS |title=Monte Carlo analyses of genetic models |journal=Nature |volume=181 |issue=4603 |pages=208–9 |year=1958 |pmid=13504138 |doi=10.1038/181208a0 |ref=harv|bibcode=1958Natur.181..208F }}</ref> [[Evolutionary algorithm|Artificial evolution]] became a widely recognised optimisation method as a result of the work of [[Ingo Rechenberg]] in the 1960s and early 1970s, who used [[Evolution strategy|evolution strategies]] to solve complex engineering problems.<ref>{{cite book |last=Rechenberg |first=Ingo |year=1973 |title=Evolutionsstrategie&nbsp;– Optimierung technischer Systeme nach Prinzipien der biologischen Evolution (PhD thesis) |publisher=Fromman-Holzboog|language = German}}</ref> [[Genetic algorithm]]s in particular became popular through the writing of [[John Henry Holland|John Holland]].<ref>{{cite book |last=Holland |first=John H. |year=1975 |title=Adaptation in Natural and Artificial Systems |publisher=[[University of Michigan Press]] |isbn=978-0-262-58111-0 |url-access=registration |url=https://archive.org/details/adaptationinnatu00holl }}</ref> As academic interest grew, dramatic increases in the power of computers allowed practical applications, including the automatic evolution of computer programs.<ref>{{cite book |last=Koza|first=John R. |year=1992 |title=Genetic Programming: On the Programming of Computers by Means of Natural Selection|publisher=[[MIT Press]] |isbn=978-0-262-11170-6}}</ref> Evolutionary algorithms are now used to solve multi-dimensional problems more efficiently than software produced by human designers, and also to optimise the design of systems.<ref>G. C. Onwubolu and B V Babu, {{cite book|url=https://www.springer.com/in/book/9783540201670|title=New Optimization Techniques in Engineering|accessdate=17 September 2016|isbn=9783540201670|last1=Onwubolu|first1=Godfrey C.|last2=Babu|first2=B. V.|date=2004-01-21}}</ref><ref>{{cite journal |author=Jamshidi M |title=Tools for intelligent control: fuzzy controllers, neural networks and genetic algorithms |journal=[[Philosophical Transactions of the Royal Society A]] |volume=361 |issue=1809 |pages=1781–808 |year=2003 |pmid=12952685 |doi=10.1098/rsta.2003.1225 |ref=harv|bibcode=2003RSPTA.361.1781J }}</ref><br />
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Simulations of evolution using evolutionary algorithms and artificial life started with the work of Nils Aall Barricelli in the 1960s, and was extended by Alex Fraser, who published a series of papers on simulation of artificial selection. Artificial evolution became a widely recognised optimisation method as a result of the work of Ingo Rechenberg in the 1960s and early 1970s, who used evolution strategies to solve complex engineering problems. Genetic algorithms in particular became popular through the writing of John Holland. As academic interest grew, dramatic increases in the power of computers allowed practical applications, including the automatic evolution of computer programs. Evolutionary algorithms are now used to solve multi-dimensional problems more efficiently than software produced by human designers, and also to optimise the design of systems.<br />
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利用演化算法和人工生命模拟进化始于20世纪60年代 Nils Aall Barricelli的工作,后来被Alex Fraser扩展,他发表了一系列关于人工选择模拟的论文。20世纪60年代和70年代早期,Ingo Rechenberg 使用演化策略解决复杂的工程问题,人工演化因此成为广泛认可的优化方法。尤其是通过约翰·霍兰德的著作,遗传算法变得流行起来。随着学术兴趣的增长,计算机能力的急剧增长使得这种算法可以实际应用起来,其中包括计算机程序的自动演化。演化算法现在被用来解决多维问题,比人类设计者生产的软件更有效,同时也可以优化系统的设计。 <br />
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== Techniques ==<br />
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== Techniques ==<br />
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== Techniques ==<br />
技术<br />
Evolutionary computing techniques mostly involve [[metaheuristic]] [[Mathematical optimization|optimization]] [[algorithm]]s. Broadly speaking, the field includes:<br />
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Evolutionary computing techniques mostly involve metaheuristic optimization algorithms. Broadly speaking, the field includes:<br />
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进化计算技术主要涉及元启发式优化算法。一般来说,这个领域包括:<br />
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*[[Ant colony optimization]]<br />
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蚁群算法<br />
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*[[Artificial immune system]]s<br />
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人工免疫系统<br />
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*[[Artificial life]] (also see [[digital organism]])<br />
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人工生命(参见电子生命)<br />
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*[[Cultural algorithm]]s<br />
文化算法<br />
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*[[Differential evolution]]<br />
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差分演化<br />
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*[[Dual-phase evolution]]<br />
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双相演化<br />
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*[[Estimation of distribution algorithm]]s<br />
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分布算法估计<br />
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*[[Evolutionary algorithm]]s<br />
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演化算法<br />
*[[Evolutionary programming]]<br />
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演化编程<br />
*[[Evolution strategy]]<br />
演化策略<br />
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*[[Gene expression programming]]<br />
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基因表达式编程算法<br />
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*[[Genetic algorithm]]<br />
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基因算法<br />
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*[[Genetic programming]]<br />
基因编程<br />
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*[[Grammatical evolution]]<br />
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文法演化<br />
*[[Learnable evolution model]]<br />
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可学习演化模型<br />
*[[Learning classifier system]]s<br />
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学习分类系统<br />
*[[Memetic algorithms]]<br />
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遗传算法<br />
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*[[Neuroevolution]]<br />
神经进化<br />
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*[[Particle swarm optimization]]<br />
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粒子群优化算法<br />
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*[[Synergistic Fibroblast Optimization]]<br />
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协作成纤维细胞优化<br />
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*[[Self-organization]] such as [[self-organizing map]]s, [[competitive learning]]<br />
自我管理(例如自组织特征映射模型 竞争性学习)<br />
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*[[Swarm intelligence]]<br />
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集群智能<br />
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== Evolutionary algorithms ==<br />
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== Evolutionary algorithms ==<br />
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演化算法<br />
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{{Main|Evolutionary algorithm}}<br />
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[[Evolutionary algorithms]] form a subset of evolutionary computation in that they generally only involve techniques implementing mechanisms inspired by [[biological evolution]] such as [[reproduction]], [[mutation]], [[Genetic recombination|recombination]], [[natural selection]] and [[survival of the fittest]]. [[Candidate solutions]] to the optimization problem play the role of individuals in a population, and the [[Loss function|cost function]] determines the environment within which the solutions "live" (see also [[fitness function]]). [[Evolution]] of the population then takes place after the repeated application of the above operators.<br />
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Evolutionary algorithms form a subset of evolutionary computation in that they generally only involve techniques implementing mechanisms inspired by biological evolution such as reproduction, mutation, recombination, natural selection and survival of the fittest. Candidate solutions to the optimization problem play the role of individuals in a population, and the cost function determines the environment within which the solutions "live" (see also fitness function). Evolution of the population then takes place after the repeated application of the above operators.<br />
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演化算法是演化计算的一个子集,因为它们通常只涉及实现生物演化机制的技术,如繁殖、变异、重组、自然选择和适者生存。最佳化问题的候选解决方案扮演了人口中个体的角色,而成本函数决定了解决方案“生存”的环境(参见适应度函数)。在重复应用上述算子之后,种群的演化就发生了。<br />
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In this process, there are two main forces that form the basis of evolutionary systems: '''Recombination''' '''mutation''' and '''crossover''' create the necessary diversity and thereby facilitate novelty, while '''selection''' acts as a force increasing quality.<br />
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In this process, there are two main forces that form the basis of evolutionary systems: Recombination mutation and crossover create the necessary diversity and thereby facilitate novelty, while selection acts as a force increasing quality.<br />
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在这个过程中,有两种主要的力量构成了演化系统的基础: 重组变异和交叉创造了必要的多样性,从而促进了新颖性,而选择作为一种力来提高质量。<br />
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Many aspects of such an evolutionary process are [[stochastic]]. Changed pieces of information due to recombination and mutation are randomly chosen. On the other hand, selection operators can be either deterministic, or stochastic. In the latter case, individuals with a higher [[Fitness function|fitness]] have a higher chance to be selected than individuals with a lower [[Fitness function|fitness]], but typically even the weak individuals have a chance to become a parent or to survive.<br />
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Many aspects of such an evolutionary process are stochastic. Changed pieces of information due to recombination and mutation are randomly chosen. On the other hand, selection operators can be either deterministic, or stochastic. In the latter case, individuals with a higher fitness have a higher chance to be selected than individuals with a lower fitness, but typically even the weak individuals have a chance to become a parent or to survive.<br />
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这种进化过程的许多方面都是随机的。由于重组和突变而改变的信息片段是随机选择的。另一方面,选择运算符可以是确定性的,也可以是随机的。在后一种情况下,适合度较高的个体比适合度较低的个体有更高的机会被选中,但通常即使是体质较弱的个体也有机会成为父本或生存下来。<br />
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== Evolutionary algorithms and biology ==<br />
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== Evolutionary algorithms and biology ==<br />
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演化算法和生物学<br />
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{{Main|Evolutionary algorithm}}<br />
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[[Genetic algorithms]] deliver methods to model [[biological systems]] and [[systems biology]] that are linked to the theory of [[dynamical systems]], since they are used to predict the future states of the system. This is just a vivid (but perhaps misleading) way of drawing attention to the orderly, well-controlled and highly structured character of development in biology.<br />
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Genetic algorithms deliver methods to model biological systems and systems biology that are linked to the theory of dynamical systems, since they are used to predict the future states of the system. This is just a vivid (but perhaps misleading) way of drawing attention to the orderly, well-controlled and highly structured character of development in biology.<br />
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遗传算法提供了与动力系统理论相关的生物系统和系统生物学模型的方法,因为它们被用来预测系统的未来状态。这只是一种生动的(但也许是误导性的)方式,提醒人们注意生物学发展的有序、控制良好和高度结构化的特征。<br />
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However, the use of algorithms and informatics, in particular of [[computational theory]], beyond the analogy to dynamical systems, is also relevant to understand evolution itself.<br />
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However, the use of algorithms and informatics, in particular of computational theory, beyond the analogy to dynamical systems, is also relevant to understand evolution itself.<br />
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然而,算法和信息学的使用,特别是计算理论的使用,超越了对动力系统的类比,这也与理解演化本身有关。<br />
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This view has the merit of recognizing that there is no central control of development; organisms develop as a result of local interactions within and between cells. The most promising ideas about program-development parallels seem to us to be ones that point to an apparently close analogy between processes within cells, and the low-level operation of modern computers.<ref>{{Cite book | chapter-url=https://plato.stanford.edu/entries/information-biological/#InfEvo | title=The Stanford Encyclopedia of Philosophy| chapter=Biological Information| publisher=Metaphysics Research Lab, Stanford University| year=2016}}</ref> Thus, biological systems are like computational machines that process input information to compute next states, such that biological systems are closer to a computation than classical dynamical system.<ref>{{cite journal |author= J.G. Diaz Ochoa |title= Elastic Multi-scale Mechanisms: Computation and Biological Evolution |journal=[[Journal of Molecular Evolution]] |volume=86 |issue=1 |pages=47–57 |year=2018 |pmid=29248946 |doi=10.1007/s00239-017-9823-7 |ref=harv|bibcode=2018JMolE..86...47D }}</ref><br />
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This view has the merit of recognizing that there is no central control of development; organisms develop as a result of local interactions within and between cells. The most promising ideas about program-development parallels seem to us to be ones that point to an apparently close analogy between processes within cells, and the low-level operation of modern computers. Thus, biological systems are like computational machines that process input information to compute next states, such that biological systems are closer to a computation than classical dynamical system.<br />
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这一观点的优点是认识到没有发育的中央控制;生物体的发育是细胞内部和细胞之间局部相互作用的结果。在我们看来,关于程序开发并行的最有前途的想法似乎是那些指出细胞内的进程与现代计算机的低级操作之间明显相似的思想。因此,生物系统就像计算机器,处理输入信息来计算下一个状态,这样生物系统比经典的动力系统更接近于计算。<br />
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Furthermore, following concepts from [[computational theory]], micro processes in biological organisms are fundamentally incomplete and undecidable ([[completeness (logic)]]), implying that “there is more than a crude metaphor behind the analogy between cells and computers.<ref>{{cite journal |author= A. Danchin |title= Bacteria as computers making computers |journal=[[FEMS Microbiol. Rev.]] |volume=33 |issue=1 |pages=3–26 |year=2008 |doi=10.1111/j.1574-6976.2008.00137.x |pmid= 19016882 |ref=harv |pmc=2704931 }}</ref><br />
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Furthermore, following concepts from computational theory, micro processes in biological organisms are fundamentally incomplete and undecidable (completeness (logic)), implying that “there is more than a crude metaphor behind the analogy between cells and computers.<br />
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此外,根据计算理论的概念,生物有机体中的微进程从根本上来说是不完整的和不可判定的(完整性(逻辑)) ,这意味着细胞和计算机之间的类比背后不只是一个粗略的比喻。<br />
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The analogy to computation extends also to the relationship between [[inheritance systems]] and biological structure, which is often thought to reveal one of the most pressing problems in explaining the origins of life.<br />
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The analogy to computation extends also to the relationship between inheritance systems and biological structure, which is often thought to reveal one of the most pressing problems in explaining the origins of life.<br />
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计算的类比也延伸到遗传系统和生物结构之间的关系,这通常被认为是揭示解释生命起源最紧迫的问题之一。<br />
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''Evolutionary automata''{{r|ldr11|ldr13|ldr14}}, a generalization of ''Evolutionary Turing machines''{{r|ldr15|ldr16}}, have been introduced in order to investigate more precisely properties of biological and evolutionary computation. In particular, they allow to obtain new results on expressiveness of evolutionary computation{{r|ldr14|ldr17}}. This confirms the initial result about undecidability of natural evolution and evolutionary algorithms and processes. ''Evolutionary finite automata'', the simplest subclass of Evolutionary automata working in ''terminal mode'' can accept arbitrary languages over a given alphabet, including non-recursively enumerable (e.g., diagonalization language) and recursively enumerable but not recursive languages (e.g., language of the universal Turing machine){{r|ldr18}}. <br />
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Evolutionary automata, a generalization of Evolutionary Turing machines, have been introduced in order to investigate more precisely properties of biological and evolutionary computation. In particular, they allow to obtain new results on expressiveness of evolutionary computation. This confirms the initial result about undecidability of natural evolution and evolutionary algorithms and processes. Evolutionary finite automata, the simplest subclass of Evolutionary automata working in terminal mode can accept arbitrary languages over a given alphabet, including non-recursively enumerable (e.g., diagonalization language) and recursively enumerable but not recursive languages (e.g., language of the universal Turing machine). <br />
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进化自动机是进化图灵机<font color="#ff8000"> 图灵机Turing machines</font>的一种推广,为了更精确地研究生物和演化计算的性质,人们引入了它。特别是,他们允许在演化计算的表现力上获得新的结果。这证实了关于自然演化和演化算法及过程不可判定性的初步结果。演化有限自动机是演化自动机中最简单的子类,在终端模式下可以接受给定字母表上的任意语言,包括非递归的可枚举语言(例如,对角化语言)和递归的可枚举但不递归语言(例如,通用图灵机语言)。<br />
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== Notable practitioners ==<br />
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== Notable practitioners ==<br />
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著名从业人员<br />
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The list of active researchers is naturally dynamic and non-exhaustive. A network analysis of the community was published in 2007.<ref>{{cite arXiv |author=J.J. Merelo and C. Cotta |title=Who is the best connected EC researcher? Centrality analysis of the complex network of authors in evolutionary computation |year=2007 |eprint=0708.2021|class=cs.CY }}</ref><br />
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The list of active researchers is naturally dynamic and non-exhaustive. A network analysis of the community was published in 2007.<br />
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活跃的研究人员名单自然是动态的,并非详尽无遗。社区的网络分析在2007年发表。<br />
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* [[Kalyanmoy Deb]]<br />
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* [[Kenneth A De Jong]]<br />
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* [[Peter J. Fleming]]<br />
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* [[David B. Fogel]]<br />
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* [[Stephanie Forrest]]<br />
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* [[David E. Goldberg]]<br />
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* [[John Henry Holland]]<br />
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* [[Theo Jansen]]<br />
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* [[John Koza]]<br />
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* [[Zbigniew Michalewicz]]<br />
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* [[Melanie Mitchell]]<br />
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* [[Peter Nordin]]<br />
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* [[Riccardo Poli]]<br />
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* [[Ingo Rechenberg]]<br />
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* [[Hans-Paul Schwefel]]<br />
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== Conferences ==<br />
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== Conferences ==<br />
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会议<br />
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The main conferences in the evolutionary computation area include <br />
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The main conferences in the evolutionary computation area include <br />
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进化计算地区的主要会议包括<br />
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* [[Association for Computing Machinery|ACM]] [[Genetic and Evolutionary Computation Conference]] (GECCO), <br />
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计算机械协会 遗传与进化计算会议 <br />
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* [[IEEE Congress on Evolutionary Computation]] (CEC), <br />
IEEE演化计算大会<br />
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* [[EvoStar]], which comprises four conferences: EuroGP, EvoApplications, EvoCOP and EvoMUSART, <br />
EvoStar,包括四个会议:EuroGP、EvoApplications、EvoCOP和EvoMUSART,<br />
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* Parallel Problem Solving from Nature (PPSN).<br />
自然并行问题解决<br />
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== See also ==<br />
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== See also ==<br />
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参见<br />
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* [[Adaptive dimensional search]]<br />
适应性多维研究<br />
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* [[Artificial development]]<br />
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人工发展<br />
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* [[Autoconstructive]]<br />
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自动建设性<br />
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* [[Developmental biology]]<br />
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发展性生物学<br />
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* [[Digital organism]]<br />
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数字化生物<br />
<br />
* [[Estimation of distribution algorithm]]<br />
<br />
分布算法估计<br />
<br />
* [[Evolutionary robotics]]<br />
演化机器人<br />
<br />
<br />
* [[Evolved antenna]]<br />
<br />
演化天线<br />
<br />
* [[Fitness approximation]]<br />
<br />
适应值近似<br />
<br />
* [[Fitness function]]<br />
<br />
适应值函数<br />
<br />
* [[Fitness landscape]]<br />
适应度景观<br />
<br />
* [[Genetic operators]]<br />
<br />
遗传算子<br />
<br />
* [[Grammatical evolution]]<br />
<br />
文法演化<br />
<br />
* [[Human-based evolutionary computation]]<br />
<br />
人类演化计算<br />
<br />
* [[Inferential programming]]<br />
<br />
推断编程<br />
<br />
* [[Interactive evolutionary computation]]<br />
<br />
互动演化计算<br />
<br />
* [[List of digital organism simulators]]<br />
<br />
数字化有机体模拟器表<br />
* [[Mutation testing]]<br />
<br />
变异测试<br />
<br />
* [[No free lunch in search and optimization]]<br />
<br />
研究和优化没有免费的午餐<br />
<br />
* [[Program synthesis]]<br />
<br />
<br />
程序综合<br />
* [[Test functions for optimization]]<br />
优化测试函数<br />
<br />
<br />
* [[Universal Darwinism]]<br />
<br />
普适达尔文主义<br />
<br />
<br />
<br />
<br />
== External links ==<br />
<br />
== External links ==<br />
<br />
外部链接<br />
<br />
*[https://plato.stanford.edu/entries/information-biological/#InfEvo/ Article in the Stanford Encyclopedia of Philosophy about Biological Information (English)]<br />
<br />
<br />
<br />
<br />
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<br />
<br />
== Bibliography ==<br />
<br />
== Bibliography ==<br />
<br />
参考书目<br />
<br />
* Th. Bäck, D.B. Fogel, and [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.amazon.com/Handbook-Evolutionary-Computation-Thomas-Back/dp/0750303921 Handbook of Evolutionary Computation], 1997, {{ISBN|0750303921}}<br />
<br />
<br />
<br />
* Th. Bäck and H.-P. Schwefel. [http://caribou.iisg.agh.edu.pl/pub/svn/age/jage/legacy/papers/mgrKA/pdf/evco.1993.1.1.pdf An overview of evolutionary algorithms for parameter optimization]. Evolutionary Computation, 1(1):1–23, 1993.<br />
<br />
<br />
<br />
* W. Banzhaf, P. Nordin, R.E. Keller, and F.D. Francone. Genetic Programming — An Introduction. Morgan Kaufmann, 1998.<br />
<br />
<br />
<br />
* S. Cagnoni, et al., [https://www.springer.com/computer+science/theoretical+computer+science/foundations+of+computations/book/978-3-540-67353-8 Real-World Applications of Evolutionary Computing], Springer-Verlag [[Lecture Notes in Computer Science]], Berlin, 2000.<br />
<br />
<br />
<br />
* R. Chiong, Th. Weise, [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.springer.com/engineering/computational+intelligence+and+complexity/book/978-3-642-23423-1 Variants of Evolutionary Algorithms for Real-World Applications], [[Springer Publishing|Springer]], 2012, {{ISBN|3642234232}}<br />
<br />
<br />
<br />
* K. A. De Jong, Evolutionary computation: a unified approach. [[MIT Press]], Cambridge MA, 2006<br />
<br />
<br />
<br />
* {{cite journal |authors=A. E. Eiben and M. Schoenauer |title=Evolutionary computing|journal=Information Processing Letters|volume=82|pages=1–6|doi=10.1016/S0020-0190(02)00204-1|year=2002}}<br />
<br />
<br />
<br />
* A. E. Eiben and J.E. Smith, [https://www.springer.com/computer/theoretical+computer+science/book/978-3-540-40184-1 Introduction to Evolutionary Computing], Springer, First edition, 2003, {{ISBN|3-540-40184-9}},<br />
<br />
<br />
<br />
* D. B. Fogel. Evolutionary Computation. Toward a New Philosophy of Machine Intelligence. IEEE Press, Piscataway, NJ, 1995.<br />
<br />
<br />
<br />
* L. J. Fogel, A. J. Owens, and M. J. Walsh. [[Artificial Intelligence]] through Simulated Evolution. New York: John Wiley, 1966.<br />
<br />
<br />
<br />
* D. E. Goldberg. Genetic algorithms in search, optimization and machine learning. Addison Wesley, 1989.<br />
<br />
<br />
<br />
* J. H. Holland. Adaptation in natural and artificial systems. [[University of Michigan Press]], Ann Arbor, 1975.<br />
<br />
<br />
<br />
* P. Hingston, L. Barone, and [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.springer.com/computer/ai/book/978-3-540-74109-1 Design by Evolution, Natural Computing Series], 2008, [[Springer Publishing|Springer]], {{ISBN|3540741097}}<br />
<br />
<br />
<br />
* J. R. Koza. Genetic Programming: On the Programming of Computers by means of Natural Evolution. MIT Press, Massachusetts, 1992.<br />
<br />
<br />
<br />
* F.J. Lobo, C.F. Lima, [[Zbigniew Michalewicz|Z. Michalewicz]] (Editors), [https://www.amazon.com/Parameter-Evolutionary-Algorithms-Computational-Intelligence/dp/3642088929/ Parameter Setting in Evolutionary Algorithms], [[Springer Publishing|Springer]], 2010, {{ISBN|3642088929}}<br />
<br />
<br />
<br />
* [[Zbigniew Michalewicz|Z. Michalewicz]], [https://www.springer.com/computer/ai/book/978-3-540-60676-5 Genetic Algorithms + Data Structures – Evolution Programs], 1996, [[Springer Publishing|Springer]], {{ISBN|3540606769}}<br />
<br />
<br />
<br />
* [[Zbigniew Michalewicz|Z. Michalewicz]] and D.B. Fogel, [https://www.springer.com/computer/theoretical+computer+science/book/978-3-540-22494-5 How to Solve It: Modern Heuristics], [[Springer Publishing|Springer]], 2004, {{ISBN|978-3-540-22494-5}}<br />
<br />
<br />
<br />
* I. Rechenberg. Evolutionstrategie: Optimierung Technischer Systeme nach Prinzipien des Biologischen Evolution. Fromman-Hozlboog Verlag, Stuttgart, 1973. {{in lang|de}}<br />
<br />
<br />
<br />
* H.-P. Schwefel. Numerical Optimization of Computer Models. John Wiley & Sons, New-York, 1981. 1995 – 2nd edition.<br />
<br />
<br />
<br />
* D. Simon. [http://academic.csuohio.edu/simond/EvolutionaryOptimization Evolutionary Optimization Algorithms]. Wiley, 2013.<br />
<br />
<br />
<br />
* {{cite journal |authors=M. Sipper, W. Fu, K. Ahuja, and J. H. Moore |title=Investigating the parameter space of evolutionary algorithms|journal=BioData Mining|volume=11|pages=2|doi=10.1186/s13040-018-0164-x|pmid=29467825|pmc=5816380|year=2018}}<br />
<br />
<br />
<br />
* {{cite arxiv |authors=Y. Zhang and S. Li. |title=PSA: A novel optimization algorithm based on survival rules of porcellio scaber |eprint=1709.09840 |class=cs.NE |year=2017 }}<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
== References ==<br />
<br />
== References ==<br />
<br />
参考资料<br />
<br />
<br />
<br />
<br />
<br />
{{reflist|refs=<br />
<br />
{{reflist|refs=<br />
<br />
{通货再膨胀 | 参考文献<br />
<br />
<ref name="ldr11">{{Cite book |doi = 10.1007/978-3-642-29694-9_9|isbn = 978-3-642-29693-2|chapter = Recursively Generated Evolutionary Turing Machines and Evolutionary Automata |editor=Xin-She Yang |title = Artificial Intelligence, Evolutionary Computing and Metaheuristics|series = Studies in Computational Intelligence|year = 2013|last1 = Burgin|first1 = Mark|last2 = Eberbach|first2 = Eugene|volume = 427|pages = 201–230 |publisher=Springer-Verlag}}</ref><br />
<br />
<br />
<br />
<ref name="ldr13">Burgin, M. and Eberbach, E. (2010) Bounded and Periodic Evolutionary Machines, in Proc. 2010 Congress on Evolutionary Computation (CEC'2010), Barcelona, Spain, 2010, pp. 1379-1386</ref><br />
<br />
<br />
<br />
<ref name="ldr14">{{Cite journal |doi = 10.1093/comjnl/bxr099|title = Evolutionary Automata: Expressiveness and Convergence of Evolutionary Computation|year = 2012|last1 = Burgin|first1 = M.|last2 = Eberbach|first2 = E.|journal = The Computer Journal|volume = 55|issue = 9|pages = 1023–1029}}</ref><br />
<br />
<br />
<br />
<ref name="ldr15">Eberbach E. (2002) On Expressiveness of Evolutionary Computation: Is EC Algorithmic?, Proc. 2002 World Congress on Computational Intelligence WCCI’2002, Honolulu, HI, 2002, 564-569.</ref><br />
<br />
<br />
<br />
<ref name="ldr16">Eberbach, E. (2005) Toward a theory of evolutionary computation, BioSystems, v. 82, pp. 1-19.</ref><br />
<br />
<br />
<br />
<ref name="ldr17">{{Cite book |doi = 10.1109/CEC.2009.4983207|isbn = 978-1-4244-2958-5|chapter = Evolutionary automata as foundation of evolutionary computation: Larry Fogel was right|title = 2009 IEEE Congress on Evolutionary Computation|year = 2009|last1 = Eberbach|first1 = Eugene|last2 = Burgin|first2 = Mark|pages = 2149–2156|publisher=IEEE}}</ref><br />
<br />
<br />
<br />
<ref name="ldr18">Hopcroft, J.E., R. Motwani, and J.D. Ullman (2001) Introduction to Automata Theory, Languages, and Computation, Addison Wesley, Boston/San Francisco/New York</ref><br />
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<br />{{Evolutionary computation}}<br />
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Br / <br />
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[[Category:Evolutionary computation| ]]<br />
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[[Category:Evolution]]<br />
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Category:Evolution<br />
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分类: 进化<br />
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<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Evolutionary computation]]. Its edit history can be viewed at [[演化计算/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19386钱学森2020-11-29T14:51:33Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
<br />
{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
<br />
{{Infobox scientist<br />
<br />
{{Infobox scientist<br />
<br />
{信息盒科学家<br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native _ name _ lang = zh-Hans-CN<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image_size = <br />
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| image_size = <br />
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图片大小 =<br />
<br />
| caption = <br />
<br />
| caption = <br />
<br />
| caption =<br />
<br />
| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
<br />
| birth_date = <br />
<br />
出生日期<br />
<br />
| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
<br />
| birth_place = Shanghai, Qing Empire<br />
<br />
出生地: 上海,清朝<br />
<br />
| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
<br />
| death_date = <br />
<br />
死亡日期<br />
<br />
| death_place = [[Beijing]], [[China]]<br />
<br />
| death_place = Beijing, China<br />
<br />
死亡地点: 中国北京<br />
<br />
| nationality = [[Nationality Law of China|Chinese]]<br />
<br />
| nationality = Chinese<br />
<br />
| 国籍 = 中国<br />
<br />
| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
<br />
| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
<br />
工程控制论 | field = 航空航天工业奖<br />
<br />
| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
<br />
| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
<br />
中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
<br />
| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
<br />
| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
<br />
加利福尼亚理工学院国立交通大学<br />
<br />
| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
<br />
| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
<br />
可压缩流体运动和反作用推进问题<br />
<br />
| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
<br />
| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
<br />
Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
<br />
| thesis_year = 1939<br />
<br />
| thesis_year = 1939<br />
<br />
论文年份 = 1939<br />
<br />
| doctoral_advisor = [[Theodore von Kármán]]<br />
<br />
| doctoral_advisor = Theodore von Kármán<br />
<br />
| doctoral_advisor = Theodore von Kármán<br />
<br />
| doctoral_students = [[Cheng Chemin]]<br />
<br />
| doctoral_students = Cheng Chemin<br />
<br />
博士生 = Cheng Chemin<br />
<br />
| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
<br />
| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
<br />
工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
<br />
| prizes = Distinguished Alumni Award from Caltech (1979)<br />
<br />
| prizes = Distinguished Alumni Award from Caltech (1979)<br />
<br />
| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
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| footnotes = <br />
<br />
| footnotes = <br />
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| 脚注 = <br />
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| signature = <br />
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| signature = <br />
<br />
签名 = <br />
<br />
| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
<br />
| spouse = <br />
<br />
配偶 =<br />
<br />
| children = Qian Yonggang<br />Qian Yungjen<br />
<br />
| children = Qian Yonggang<br />Qian Yungjen<br />
<br />
| children = 钱永刚 < br/> 钱永仁<br />
<br />
| module = {{Chinese |child = yes<br />
<br />
| module = {{Chinese |child = yes<br />
<br />
{ Chinese | child = yes<br />
<br />
|s = 钱学森<br />
<br />
|s = 钱学森<br />
<br />
|s = 钱学森<br />
<br />
|p = Qián Xuésēn<br />
<br />
|p = Qián Xuésēn<br />
<br />
|p = Qián Xuésēn<br />
<br />
|t = 錢學森<br />
<br />
|t = 錢學森<br />
<br />
|t = 錢學森<br />
<br />
|w = Ch'ien Hsüeh-sen<br />
<br />
|w = Ch'ien Hsüeh-sen<br />
<br />
|w = Ch'ien Hsüeh-sen<br />
<br />
|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
<br />
|l = Qian (surname) learning-forest<br />
<br />
| l = 倩(姓)学林<br />
<br />
|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
<br />
|mi=<br />
<br />
| mi =<br />
<br />
}}<br />
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}}<br />
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}}<br />
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}}<br />
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}}<br />
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}}<br />
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<br />
'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
<br />
Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
<br />
钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
<br />
During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
<br />
在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全级别。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
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在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,乘坐美国总统邮轮克利夫兰号,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终促成了中国原子弹试验和氢弹试验的首次成功 ,使中国成为第五个核武器国家,并实现了历史上最快的裂变-聚变发展。此外,钱学森的工作还促成了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父”,绰号“火箭之王”。他是公认的两弹一星奠基人之一<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱学森当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他是曾参与中美航空航天事业的机械工程师钱学榘Hsue-Chu Tsien的表弟;他的侄子是2008年诺贝尔化学奖获得者钱永健Roger Y. Tsien。<br />
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== Early life and education 早期生活和教育经历==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱学森生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳是同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,主修铁路管理。他曾在南昌空军基地实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他被称为Hsue-Shen Tsien。他受到了美国工程教育方法的影响,尤其是对实验的重视。这与许多中国科学家所采用的当代方法形成了鲜明对比,后者强调理论元素,而不是“亲身体验”。钱学森的实验包括使用水银压力计绘制皮托管压力图。 <br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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西奥多·冯·卡门,钱学森的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
1936年的一天,他来找我咨询进一步的研究生学习。这是我们第一次见面。我抬起头来,注意到一个身材矮小、神情严肃的年轻人,他回答我的问题异常准确。他的敏锐和敏捷的思维给我留下了深刻的印象,我建议他去加州理工学院深造。钱学森同意了。他和我一起做了许多数学题。我发现他很有想象力,他有数学才能,他成功地把自然现象的物理图像形象化。即使是一个年轻的学生,他也帮助我理清了一些关于几个难题的想法。这样的天赋是我不常遇到的,钱和我成了亲密的同事。<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱学森被吸引了进来: “钱学森喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States 美国生涯==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希 普朗特(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯·卡门和钱学森为美国服务; 1956年后,钱学森为中国服务。钱保留的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯·卡门的博士生导师,而冯·卡门则是钱学森的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年来到加州理工学院后不久,钱学森就对弗兰克·马利纳(Frank Malina)、冯·卡门的其他学生以及他们的同伴(包括杰克·帕森斯)的火箭想法着迷。他和他的同学们一起,在加州理工学院的古根海姆航空实验室参与了与火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小组”的绰号。钱学森于1939年在加州理工学院获得博士学位 <br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱学森参与曼哈顿计划,帮助美国成功研制出第一颗原子弹。1943年,钱学森和他们火箭研究小组的另外两名成员起草了第一份文件,使用喷气推进实验室(JPL)这个名字,这最初是向陆军提出的一项针对德国V-2火箭发展导弹的建议。这促成了1944年的私人飞机A,以及后来的下士,WAC下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱学森作为一名拥有安全级别的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯·卡门在提到钱学森时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的动力。”在此期间,他致力于设计一种洲际航天飞机,它是美国航天飞机的前身,并为后来X-20 Dyna-Soar的生产带来了灵感。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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钱学森娶了著名歌剧演员蒋英,蒋百里和他的妻子:日本护士SatôYato的女儿。蒋百里是国民党领导人蒋介石的军事战略家和顾问。钱学森夫妇于1947年9月14日在上海结婚,育有两个孩子;他们的儿子钱永刚(又称Yucon Tsien)于1948年10月13日出生在波士顿,而他们的女儿钱永珍则出生于1950年初,当时全家住在加州帕萨迪纳。 <br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱学森回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯·卡门的推荐下,钱学森成为加州理工学院喷气推进教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱学森获得永久居留许可,<br />
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=== Detention软禁 ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱学森是共产主义者,但是他的安全级别并没有被吊销。然而,1950年6月6日,他的安全级别被吊销,钱学森受到联邦调查局的审问。两周后,钱学森宣布他将辞去加州理工学院的工作,回到中国,那时的中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱学森与当时的海军副部长丹·A·金博尔(Dan A. Kimball)就这个问题进行了交谈,钱学森私下认识金博尔。钱学森告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱学森暗示,他仍然打算离开中国,并说“我是中国人。”,我不想制造杀死我同胞的武器,就这么简单。”金博尔接着说,“我不会让你回中国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱学森回中国的公司向美国海关透露,钱学森随身物品中有一些文件标有“机密”或“秘密”字样后,美国官员从帕萨迪纳的一个仓库里查获了这些文件。美国移民和归化局于8月25日发出逮捕令。钱学森称,这些加盖安全章的文件大多是自己写的,分类已经过时,并补充说,“有一些图纸和对数表等,可能被人误认为是代码。”材料中包括一本剪贴簿,上面有对那些被控从事原子间谍活动的人进行审判的新闻剪报,比如克劳斯·福克斯。随后对这些文件的检查表明,这些文件中没有任何机密材料。韦恩鲍姆的审判于8月30日开始,弗兰克·奥本海默和帕森斯都出庭作不利于他的证明。韦恩鲍姆被判犯有伪证罪,判处4年徒刑。钱学森于1950年9月6日被羁押问话 <br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱学森被宣布驱逐出境,未经允许不得离开洛杉矶县,实际上将他软禁起来。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
1947年,钱学森带着他的新娘从中国回来时,他在一份移民调查问卷中回答“不”,该问卷询问他是否曾是一个鼓吹以武力推翻美国政府的组织的成员。这一点,加上1938年的一份美国[CPUSA |共产党]]文件上面写着钱学森的名字,被用来证明钱学森是一个国家安全威胁。检方还引述了一次盘问环节,钱学森说,“我对中国人民有效忠义务”,如果美国和共产主义中国发生冲突,他“肯定不会”让美国政府替他决定效忠谁。<br />
During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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1951年4月26日,钱学森被宣布被驱逐出境,并禁止未经许可离开[加利福尼亚州洛杉矶市]],实际上对他实行了[[软禁]]。<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
在这期间,钱学森写了《工程控制论》,1954年由[[McGraw-Hill]]出版。这本书论述了稳定[[伺服机构]]的实践。在其18章中,它考虑了许多变量系统的非交互控制,[[微扰理论]]的控制设计,以及[[约翰.冯.诺依曼]]的[[误差控制]理论(第18章)。埃兹拉·克伦德尔回顾了《富兰克林学院学报》这本书,指出“对于那些对复杂[[控制系统]]整体理论感兴趣的人来说,很难夸大钱学森的书的价值。”显然,钱学森的方法主要是实用的,正如克伦德尔指出的,对于伺服机构,“通常的线性稳定性设计准则是不充分的,必须使用由问题的物理性质产生的其他准则。” <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱学森留在美国的金博尔副国务卿评论了他的遭遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China回到祖国 ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
钱学森成为美中两国长达五年秘密外交和谈判的对象。在此期间,钱学森一直生活在监视之下,有权任教,没有任何机密的研究任务。钱学森在被监禁期间得到加州理工学院同事的支持,包括总统[[李·杜布里奇]],后者飞往华盛顿为钱的案件辩护。加州理工学院指定律师格兰特·库伯 为钱辩护。<br />
He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科学技术大学的建立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭之外,钱学森在许多领域都有研究。他是系统学的创造者之一,在科技系统、体科学、工程科学、军事科学、社会科学、自然科学、地理、哲学、文学艺术、教育等领域做出了贡献。他在系统科学领域的概念、理论和方法上的进步包括对开放的复杂巨系统的研究。此外,他还帮助建立了中国复杂性科学学院。 <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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从20世纪80年代起,钱学森倡导对中医学、气功进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
回国后,钱学森在火箭科学领域开始了一段非常成功的职业生涯,这得益于他过去的成就以及中国政府对其核研究的支持而获得的声誉。他领导并最终成为中国导弹项目之父,该项目建造了[[东风(导弹)|东风弹道导弹]]和[[长征(火箭家族)|长征太空火箭]]。<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies中国核计划及其他研究 ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
1956年10月,任【【中华人民共和国国防部|国防部】】的【【中国航天科技集团公司|第五研究院】】所长,负责弹道导弹和核武器的研制。他是促成1964年10月16日“596”原子弹试验和1967年6月17日“6号试验”氢弹试验成功的总体努力的一部分。这是历史上最快的一次[核裂变|裂变]]到[[核聚变|聚变]]的发展,为32个月,相比之下,美国为86个月,苏联为75个月,使中国领先于[[法国]等西方大国获得了[[热核装置]]。<br />
Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱学森于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
钱学森是一位在美国陷入红色恐慌的著名科学家,这使他在[[毛泽东]时代及其后的时代有着相当大的影响力。钱学森最终升入党内,成为[中共中央委员会]委员。他加入了“中国航天计划——从构想到载人航天”计划。<br />
In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱学森被授予加州理工学院杰出校友奖。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友弗兰克·马博(Frank·Marble)的帮助下,在一个广为报道的仪式上把它带到了家中。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。 <br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱学森访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱学森“对美国政府失去了信任” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
1958年,他积极参与中国科学技术大学(USTC)的创建,并担任该校现代力学系主任若干年。 <br />
The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周和年度空间技术人物。这项认可不仅仅是一种荣誉,更是授予过去一年里对航空业影响最大的人。此外,那一年,中国中央电视台将钱学森评为中国最鼓舞人心的11位人物之一。 <br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
从20世纪80年代起,钱学森倡导对[[中医]]、[[气功]]进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会(一个国际系统工程荣誉学会),将钱学森位列四名荣誉会员之一。<br />
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== Later life 晚年生活==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱学森在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱学森》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
钱学森于1991年退休,安静地生活在北京,拒绝与西方人交谈。<br />
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In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
1979年,钱学森因其成就被加州理工学院授予“杰出校友奖”。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友的帮助下,在一个被广泛报道的仪式上把它带到了家里。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。<br />
Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯·S·A·科里(James S.A. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯·克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
中美关系正常化后,钱学森曾受美国航空航天研究所邀请访问美国,但他拒绝了邀请,因为他希望就被拘留一事正式道歉。在2002年发表的一篇回忆录中,马尔布尔说,他相信钱学森“对美国政府失去了信心”,但他“对美国人民一直怀有非常温暖的感情”。<br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
中国政府于1992年启动了载人航天计划,据报道,由于俄罗斯在太空的历史悠久,俄罗斯也给予了一些帮助。钱学森的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射神舟五号任务。钱学森老人能够在病床上通过电视观看中国首次载人航天任务。 <br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
2008年,他被评为航空周和年度空间技术人物。这一表彰并不是一种荣誉,而是授予在过去一年中被认为对航空业影响最大的人。[19][46]此外,当年中国中央电视台将钱学森评为中国最具启发性的十一位人物之一。<br />
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In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
2009年7月,国际系统工程荣誉学会欧米茄阿尔法协会(Omega Alpha Association)将钱学森(H.S.Tsien)命名为四位荣誉会员之一 <br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
2009年10月31日,钱学森在北京逝世,享年98岁 <br />
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A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
一部由张建亚执导、陈坤饰演钱学森的中国电影作品《钱学森》于2011年12月11日在亚洲和北美同时上映,并于2012年3月2日在中国上映。<br />
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== In popular culture在流行文化 ==<br />
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[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
科幻作家阿瑟·C·克拉克在1982年的小说《2010年:奥德赛二号》中,以他的名字命名了一艘中国太空船。科里的科幻小说系列《无边无际》也以他的名字命名了一艘火星飞船(麦克恩·雪森)。在1981年美国华裔科学家詹姆斯·克莱维尔(James Clavell)的小说《贵族之家》(Noble House)中,余博士是钱学森博士的虚构版本。<br />
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== Scientific papers 科学论文==<br />
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* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
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* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
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* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
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* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
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* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
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* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
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* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
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* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
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* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
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* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
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* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
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* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
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* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
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* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
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* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
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== Monographs专著 ==<br />
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* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
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** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
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* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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== See also参见 ==<br />
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{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
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* [[Aeronautics]]<br />
航空学<br />
* [[Engineering cybernetics]]<br />
工程控制论 <br />
* [[Jet Propulsion Laboratory]]<br />
喷气推进实验室 <br />
* [[Theodore von Kármán]]<br />
西奥多·冯·卡门 <br />
* [[Chien-Shiung Wu]]<br />
吴建雄<br />
* [[Ye Qisun]]<br />
叶企孙<br />
* [[Guo Yonghuai]]<br />
郭永怀<br />
Works cited<br />
<br />
引用作品<br />
<br />
* [[Hsue-Chu Tsien]]<br />
钱学森<br />
* [[McCarthyism]]<br />
麦卡锡主义<br />
* [[People's Liberation Army Rocket Force]]<br />
中国人民解放军火箭部队<br />
** [[Dongfeng (missile)]]<br />
东风导弹<br />
* [[Chinese space program]]<br />
中国航天计划 <br />
** [[Long March (rocket family)]]<br />
长征(火箭家族)<br />
* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
中国与大规模杀伤性武器|中国核计划 <br />
** [[596 (nuclear test)|Project 596]]<br />
596(核试验)|项目596<br />
** [[Test No. 6]]<br />
试验6<br />
* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
中国航天科技集团公司(原名国防部第五学院)<br />
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== References参考 ==<br />
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{{Reflist}}<br />
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;Works cited<br />
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{{refbegin}}<br />
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* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
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* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
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* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
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* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
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* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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{{refend}}<br />
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类别: 八宝山革命公墓的葬礼<br />
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[[Category:Jet Propulsion Laboratory faculty]]<br />
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Category:Victims of McCarthyism<br />
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类别: 麦卡锡主义的受害者<br />
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<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19384钱学森2020-11-29T14:50:30Z<p>Henry:</p>
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<div>此词条暂由Henry翻译<br />
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{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
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{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
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{{Infobox scientist<br />
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{{Infobox scientist<br />
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{信息盒科学家<br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name_lang = zh-Hans-CN<br />
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| native_name_lang = zh-Hans-CN<br />
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| native _ name _ lang = zh-Hans-CN<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
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| birth_date = <br />
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出生日期<br />
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| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
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| birth_place = Shanghai, Qing Empire<br />
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出生地: 上海,清朝<br />
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| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
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| death_date = <br />
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死亡日期<br />
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| death_place = [[Beijing]], [[China]]<br />
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| death_place = Beijing, China<br />
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死亡地点: 中国北京<br />
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| nationality = [[Nationality Law of China|Chinese]]<br />
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| nationality = Chinese<br />
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| 国籍 = 中国<br />
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| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
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| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
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工程控制论 | field = 航空航天工业奖<br />
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| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
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| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
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中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
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| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
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| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
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加利福尼亚理工学院国立交通大学<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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可压缩流体运动和反作用推进问题<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
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| thesis_year = 1939<br />
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| thesis_year = 1939<br />
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论文年份 = 1939<br />
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| doctoral_advisor = [[Theodore von Kármán]]<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_students = [[Cheng Chemin]]<br />
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| doctoral_students = Cheng Chemin<br />
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博士生 = Cheng Chemin<br />
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| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
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| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
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工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
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| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
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配偶 =<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = 钱永刚 < br/> 钱永仁<br />
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| module = {{Chinese |child = yes<br />
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| module = {{Chinese |child = yes<br />
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{ Chinese | child = yes<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
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|l = Qian (surname) learning-forest<br />
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| l = 倩(姓)学林<br />
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|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
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'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
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Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
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钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
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During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
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在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全级别。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
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在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,乘坐美国总统邮轮克利夫兰号,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终促成了中国原子弹试验和氢弹试验的首次成功 ,使中国成为第五个核武器国家,并实现了历史上最快的裂变-聚变发展。此外,钱学森的工作还促成了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父”,绰号“火箭之王”。他是公认的两弹一星奠基人之一<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱学森当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他是曾参与中美航空航天事业的机械工程师钱学榘Hsue-Chu Tsien的表弟;他的侄子是2008年诺贝尔化学奖获得者钱永健Roger Y. Tsien。<br />
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== Early life and education 早期生活和教育经历==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱学森生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳是同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,主修铁路管理。他曾在南昌空军基地实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他被称为Hsue-Shen Tsien。他受到了美国工程教育方法的影响,尤其是对实验的重视。这与许多中国科学家所采用的当代方法形成了鲜明对比,后者强调理论元素,而不是“亲身体验”。钱学森的实验包括使用水银压力计绘制皮托管压力图。 <br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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西奥多·冯·卡门,钱学森的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
1936年的一天,他来找我咨询进一步的研究生学习。这是我们第一次见面。我抬起头来,注意到一个身材矮小、神情严肃的年轻人,他回答我的问题异常准确。他的敏锐和敏捷的思维给我留下了深刻的印象,我建议他去加州理工学院深造。钱学森同意了。他和我一起做了许多数学题。我发现他很有想象力,他有数学才能,他成功地把自然现象的物理图像形象化。即使是一个年轻的学生,他也帮助我理清了一些关于几个难题的想法。这样的天赋是我不常遇到的,钱和我成了亲密的同事。<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱学森被吸引了进来: “钱学森喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States 美国生涯==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希 普朗特(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯·卡门和钱学森为美国服务; 1956年后,钱学森为中国服务。钱保留的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯·卡门的博士生导师,而冯·卡门则是钱学森的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年来到加州理工学院后不久,钱学森就对弗兰克·马利纳(Frank Malina)、冯·卡门的其他学生以及他们的同伴(包括杰克·帕森斯)的火箭想法着迷。他和他的同学们一起,在加州理工学院的古根海姆航空实验室参与了与火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小组”的绰号。钱学森于1939年在加州理工学院获得博士学位 <br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱学森参与曼哈顿计划,帮助美国成功研制出第一颗原子弹。1943年,钱学森和他们火箭研究小组的另外两名成员起草了第一份文件,使用喷气推进实验室(JPL)这个名字,这最初是向陆军提出的一项针对德国V-2火箭发展导弹的建议。这促成了1944年的私人飞机A,以及后来的下士,WAC下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱学森作为一名拥有安全级别的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯·卡门在提到钱学森时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的动力。”在此期间,他致力于设计一种洲际航天飞机,它是美国航天飞机的前身,并为后来X-20 Dyna-Soar的生产带来了灵感。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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钱学森娶了著名歌剧演员蒋英,蒋百里和他的妻子:日本护士SatôYato的女儿。蒋百里是国民党领导人蒋介石的军事战略家和顾问。钱学森夫妇于1947年9月14日在上海结婚,育有两个孩子;他们的儿子钱永刚(又称Yucon Tsien)于1948年10月13日出生在波士顿,而他们的女儿钱永珍则出生于1950年初,当时全家住在加州帕萨迪纳。 <br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱学森回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯·卡门的推荐下,钱学森成为加州理工学院喷气推进教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱学森获得永久居留许可,<br />
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=== Detention软禁 ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱学森是共产主义者,但是他的安全级别并没有被吊销。然而,1950年6月6日,他的安全级别被吊销,钱学森受到联邦调查局的审问。两周后,钱学森宣布他将辞去加州理工学院的工作,回到中国,那时的中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱学森与当时的海军副部长丹·A·金博尔(Dan A. Kimball)就这个问题进行了交谈,钱学森私下认识金博尔。钱学森告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱学森暗示,他仍然打算离开中国,并说“我是中国人。”,我不想制造杀死我同胞的武器,就这么简单。”金博尔接着说,“我不会让你回中国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱学森回中国的公司向美国海关透露,钱学森随身物品中有一些文件标有“机密”或“秘密”字样后,美国官员从帕萨迪纳的一个仓库里查获了这些文件。美国移民和归化局于8月25日发出逮捕令。钱学森称,这些加盖安全章的文件大多是自己写的,分类已经过时,并补充说,“有一些图纸和对数表等,可能被人误认为是代码。”材料中包括一本剪贴簿,上面有对那些被控从事原子间谍活动的人进行审判的新闻剪报,比如克劳斯·福克斯。随后对这些文件的检查表明,这些文件中没有任何机密材料。韦恩鲍姆的审判于8月30日开始,弗兰克·奥本海默和帕森斯都出庭作不利于他的证明。韦恩鲍姆被判犯有伪证罪,判处4年徒刑。钱学森于1950年9月6日被羁押问话 <br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱学森被宣布驱逐出境,未经允许不得离开洛杉矶县,实际上将他软禁起来。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
1947年,钱学森带着他的新娘从中国回来时,他在一份移民调查问卷中回答“不”,该问卷询问他是否曾是一个鼓吹以武力推翻美国政府的组织的成员。这一点,加上1938年的一份美国[CPUSA |共产党]]文件上面写着钱学森的名字,被用来证明钱学森是一个国家安全威胁。检方还引述了一次盘问环节,钱学森说,“我对中国人民有效忠义务”,如果美国和共产主义中国发生冲突,他“肯定不会”让美国政府替他决定效忠谁。<br />
During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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1951年4月26日,钱学森被宣布被驱逐出境,并禁止未经许可离开[加利福尼亚州洛杉矶市]],实际上对他实行了[[软禁]]。<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
在这期间,钱学森写了《工程控制论》,1954年由[[McGraw-Hill]]出版。这本书论述了稳定[[伺服机构]]的实践。在其18章中,它考虑了许多变量系统的非交互控制,[[微扰理论]]的控制设计,以及[[约翰.冯.诺依曼]]的[[误差控制]理论(第18章)。埃兹拉·克伦德尔回顾了《富兰克林学院学报》这本书,指出“对于那些对复杂[[控制系统]]整体理论感兴趣的人来说,很难夸大钱学森的书的价值。”显然,钱学森的方法主要是实用的,正如克伦德尔指出的,对于伺服机构,“通常的线性稳定性设计准则是不充分的,必须使用由问题的物理性质产生的其他准则。” <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱学森留在美国的金博尔副国务卿评论了他的遭遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China回到祖国 ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
钱学森成为美中两国长达五年秘密外交和谈判的对象。在此期间,钱学森一直生活在监视之下,有权任教,没有任何机密的研究任务。钱学森在被监禁期间得到加州理工学院同事的支持,包括总统[[李·杜布里奇]],后者飞往华盛顿为钱的案件辩护。加州理工学院指定律师格兰特·库伯 为钱辩护。<br />
He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科学技术大学的建立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭之外,钱学森在许多领域都有研究。他是系统学的创造者之一,在科技系统、体科学、工程科学、军事科学、社会科学、自然科学、地理、哲学、文学艺术、教育等领域做出了贡献。他在系统科学领域的概念、理论和方法上的进步包括对开放的复杂巨系统的研究。此外,他还帮助建立了中国复杂性科学学院。 <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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从20世纪80年代起,钱学森倡导对中医学、气功进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
回国后,钱学森在火箭科学领域开始了一段非常成功的职业生涯,这得益于他过去的成就以及中国政府对其核研究的支持而获得的声誉。他领导并最终成为中国导弹项目之父,该项目建造了[[东风(导弹)|东风弹道导弹]]和[[长征(火箭家族)|长征太空火箭]]。<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies中国核计划及其他研究 ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
1956年10月,任【【中华人民共和国国防部|国防部】】的【【中国航天科技集团公司|第五研究院】】所长,负责弹道导弹和核武器的研制。他是促成1964年10月16日“596”原子弹试验和1967年6月17日“6号试验”氢弹试验成功的总体努力的一部分。这是历史上最快的一次[核裂变|裂变]]到[[核聚变|聚变]]的发展,为32个月,相比之下,美国为86个月,苏联为75个月,使中国领先于[[法国]等西方大国获得了[[热核装置]]。<br />
Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱学森于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
钱学森是一位在美国陷入红色恐慌的著名科学家,这使他在[[毛泽东]时代及其后的时代有着相当大的影响力。钱学森最终升入党内,成为[中共中央委员会]委员。他加入了“中国航天计划——从构想到载人航天”计划。<br />
In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱学森被授予加州理工学院杰出校友奖。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友弗兰克·马博(Frank·Marble)的帮助下,在一个广为报道的仪式上把它带到了家中。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。 <br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱学森访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱学森“对美国政府失去了信任” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
1958年,他积极参与中国科学技术大学(USTC)的创建,并担任该校现代力学系主任若干年。 <br />
The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周和年度空间技术人物。这项认可不仅仅是一种荣誉,更是授予过去一年里对航空业影响最大的人。此外,那一年,中国中央电视台将钱学森评为中国最鼓舞人心的11位人物之一。 <br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
从20世纪80年代起,钱学森倡导对[[中医]]、[[气功]]进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会(一个国际系统工程荣誉学会),将钱学森位列四名荣誉会员之一。<br />
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== Later life 晚年生活==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱学森在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱学森》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
钱学森于1991年退休,安静地生活在北京,拒绝与西方人交谈。<br />
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In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
1979年,钱学森因其成就被加州理工学院授予“杰出校友奖”。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友的帮助下,在一个被广泛报道的仪式上把它带到了家里。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。<br />
Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯·S·A·科里(James S.A. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯·克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
中美关系正常化后,钱学森曾受美国航空航天研究所邀请访问美国,但他拒绝了邀请,因为他希望就被拘留一事正式道歉。在2002年发表的一篇回忆录中,马尔布尔说,他相信钱学森“对美国政府失去了信心”,但他“对美国人民一直怀有非常温暖的感情”。<br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
中国政府于1992年启动了载人航天计划,据报道,由于俄罗斯在太空的历史悠久,俄罗斯也给予了一些帮助。钱学森的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射神舟五号任务。钱学森老人能够在病床上通过电视观看中国首次载人航天任务。 <br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
2008年,他被评为航空周和年度空间技术人物。这一表彰并不是一种荣誉,而是授予在过去一年中被认为对航空业影响最大的人。[19][46]此外,当年中国中央电视台将钱学森评为中国最具启发性的十一位人物之一。<br />
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In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
2009年7月,国际系统工程荣誉学会欧米茄阿尔法协会(Omega Alpha Association)将钱学森(H.S.Tsien)命名为四位荣誉会员之一 <br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
2009年10月31日,钱学森在北京逝世,享年98岁 <br />
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A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
一部由张建亚执导、陈坤饰演钱学森的中国电影作品《钱学森》于2011年12月11日在亚洲和北美同时上映,并于2012年3月2日在中国上映。<br />
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== In popular culture在流行文化 ==<br />
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[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
<br />
<br />
<br />
== Scientific papers 科学论文==<br />
<br />
* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
<br />
* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
<br />
* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
<br />
* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
<br />
* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
<br />
* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
<br />
* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
<br />
* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
<br />
* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
<br />
* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
<br />
* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
<br />
* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
<br />
* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
<br />
* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
<br />
* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
<br />
* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
<br />
* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
<br />
* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
<br />
* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
<br />
* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
<br />
* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
<br />
<br />
<br />
== Monographs专著 ==<br />
<br />
* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
<br />
** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
<br />
* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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<br />
<br />
== See also参见 ==<br />
<br />
{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
<br />
* [[Aeronautics]]<br />
航空学<br />
* [[Engineering cybernetics]]<br />
工程控制论 <br />
* [[Jet Propulsion Laboratory]]<br />
喷气推进实验室 <br />
* [[Theodore von Kármán]]<br />
西奥多·冯·卡门 <br />
* [[Chien-Shiung Wu]]<br />
吴建雄<br />
* [[Ye Qisun]]<br />
叶企孙<br />
* [[Guo Yonghuai]]<br />
郭永怀<br />
Works cited<br />
<br />
引用作品<br />
<br />
* [[Hsue-Chu Tsien]]<br />
钱学森<br />
* [[McCarthyism]]<br />
麦卡锡主义<br />
* [[People's Liberation Army Rocket Force]]<br />
中国人民解放军火箭部队<br />
** [[Dongfeng (missile)]]<br />
东风导弹<br />
* [[Chinese space program]]<br />
中国航天计划 <br />
** [[Long March (rocket family)]]<br />
长征(火箭家族)<br />
* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
中国与大规模杀伤性武器|中国核计划 <br />
** [[596 (nuclear test)|Project 596]]<br />
596(核试验)|项目596<br />
** [[Test No. 6]]<br />
试验6<br />
* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
中国航天科技集团公司(原名国防部第五学院)<br />
<br />
<br />
== References参考 ==<br />
<br />
{{Reflist}}<br />
<br />
<br />
<br />
;Works cited<br />
<br />
{{refbegin}}<br />
<br />
* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
<br />
* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
<br />
* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
<br />
* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
<br />
* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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{{refend}}<br />
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* [https://web.archive.org/web/20060502182903/http://www.astronautix.com/articles/china.htm China], Encyclopedia Astronautica<br />
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* {{cite web |url = http://archives.caltech.edu/news/tsien.html |title = In the News: The father of Chinese rocketry |author = <!--Staff writer(s); no by-line.--> |date = |website = Caltech |access-date = {{Date|2015-02-02|dmy}} }}<br />
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<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19383钱学森2020-11-29T14:49:41Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
<br />
{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
<br />
{{Infobox scientist<br />
<br />
{{Infobox scientist<br />
<br />
{信息盒科学家<br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native _ name _ lang = zh-Hans-CN<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image_size = <br />
<br />
| image_size = <br />
<br />
图片大小 =<br />
<br />
| caption = <br />
<br />
| caption = <br />
<br />
| caption =<br />
<br />
| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
<br />
| birth_date = <br />
<br />
出生日期<br />
<br />
| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
<br />
| birth_place = Shanghai, Qing Empire<br />
<br />
出生地: 上海,清朝<br />
<br />
| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
<br />
| death_date = <br />
<br />
死亡日期<br />
<br />
| death_place = [[Beijing]], [[China]]<br />
<br />
| death_place = Beijing, China<br />
<br />
死亡地点: 中国北京<br />
<br />
| nationality = [[Nationality Law of China|Chinese]]<br />
<br />
| nationality = Chinese<br />
<br />
| 国籍 = 中国<br />
<br />
| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
<br />
| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
<br />
工程控制论 | field = 航空航天工业奖<br />
<br />
| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
<br />
| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
<br />
中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
<br />
| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
<br />
| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
<br />
加利福尼亚理工学院国立交通大学<br />
<br />
| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
<br />
| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
<br />
可压缩流体运动和反作用推进问题<br />
<br />
| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
<br />
| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
<br />
Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
<br />
| thesis_year = 1939<br />
<br />
| thesis_year = 1939<br />
<br />
论文年份 = 1939<br />
<br />
| doctoral_advisor = [[Theodore von Kármán]]<br />
<br />
| doctoral_advisor = Theodore von Kármán<br />
<br />
| doctoral_advisor = Theodore von Kármán<br />
<br />
| doctoral_students = [[Cheng Chemin]]<br />
<br />
| doctoral_students = Cheng Chemin<br />
<br />
博士生 = Cheng Chemin<br />
<br />
| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
<br />
| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
<br />
工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
<br />
| prizes = Distinguished Alumni Award from Caltech (1979)<br />
<br />
| prizes = Distinguished Alumni Award from Caltech (1979)<br />
<br />
| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
<br />
| footnotes = <br />
<br />
| footnotes = <br />
<br />
| 脚注 = <br />
<br />
| signature = <br />
<br />
| signature = <br />
<br />
签名 = <br />
<br />
| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
<br />
| spouse = <br />
<br />
配偶 =<br />
<br />
| children = Qian Yonggang<br />Qian Yungjen<br />
<br />
| children = Qian Yonggang<br />Qian Yungjen<br />
<br />
| children = 钱永刚 < br/> 钱永仁<br />
<br />
| module = {{Chinese |child = yes<br />
<br />
| module = {{Chinese |child = yes<br />
<br />
{ Chinese | child = yes<br />
<br />
|s = 钱学森<br />
<br />
|s = 钱学森<br />
<br />
|s = 钱学森<br />
<br />
|p = Qián Xuésēn<br />
<br />
|p = Qián Xuésēn<br />
<br />
|p = Qián Xuésēn<br />
<br />
|t = 錢學森<br />
<br />
|t = 錢學森<br />
<br />
|t = 錢學森<br />
<br />
|w = Ch'ien Hsüeh-sen<br />
<br />
|w = Ch'ien Hsüeh-sen<br />
<br />
|w = Ch'ien Hsüeh-sen<br />
<br />
|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
<br />
|l = Qian (surname) learning-forest<br />
<br />
| l = 倩(姓)学林<br />
<br />
|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
<br />
|mi=<br />
<br />
| mi =<br />
<br />
}}<br />
<br />
}}<br />
<br />
}}<br />
<br />
}}<br />
<br />
}}<br />
<br />
}}<br />
<br />
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'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
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Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
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钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
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During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
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在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全级别。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
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在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,乘坐美国总统邮轮克利夫兰号,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终促成了中国原子弹试验和氢弹试验的首次成功 ,使中国成为第五个核武器国家,并实现了历史上最快的裂变-聚变发展。此外,钱学森的工作还促成了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父”,绰号“火箭之王”。他是公认的两弹一星奠基人之一<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱学森当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他是曾参与中美航空航天事业的机械工程师钱学榘Hsue-Chu Tsien的表弟;他的侄子是2008年诺贝尔化学奖获得者钱永健Roger Y. Tsien。<br />
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== Early life and education 早期生活和教育经历==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱学森生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳是同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,主修铁路管理。他曾在南昌空军基地实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他被称为Hsue-Shen Tsien。他受到了美国工程教育方法的影响,尤其是对实验的重视。这与许多中国科学家所采用的当代方法形成了鲜明对比,后者强调理论元素,而不是“亲身体验”。钱学森的实验包括使用水银压力计绘制皮托管压力图。 <br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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西奥多·冯·卡门,钱学森的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
1936年的一天,他来找我咨询进一步的研究生学习。这是我们第一次见面。我抬起头来,注意到一个身材矮小、神情严肃的年轻人,他回答我的问题异常准确。他的敏锐和敏捷的思维给我留下了深刻的印象,我建议他去加州理工学院深造。钱学森同意了。他和我一起做了许多数学题。我发现他很有想象力,他有数学才能,他成功地把自然现象的物理图像形象化。即使是一个年轻的学生,他也帮助我理清了一些关于几个难题的想法。这样的天赋是我不常遇到的,钱和我成了亲密的同事。<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱学森被吸引了进来: “钱学森喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States 美国生涯==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希 普朗特(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯·卡门和钱学森为美国服务; 1956年后,钱学森为中国服务。钱保留的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯·卡门的博士生导师,而冯·卡门则是钱学森的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年来到加州理工学院后不久,钱学森就对弗兰克·马利纳(Frank Malina)、冯·卡门的其他学生以及他们的同伴(包括杰克·帕森斯)的火箭想法着迷。他和他的同学们一起,在加州理工学院的古根海姆航空实验室参与了与火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小组”的绰号。钱学森于1939年在加州理工学院获得博士学位 <br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱学森参与曼哈顿计划,帮助美国成功研制出第一颗原子弹。1943年,钱学森和他们火箭研究小组的另外两名成员起草了第一份文件,使用喷气推进实验室(JPL)这个名字,这最初是向陆军提出的一项针对德国V-2火箭发展导弹的建议。这促成了1944年的私人飞机A,以及后来的下士,WAC下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱学森作为一名拥有安全级别的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯·卡门在提到钱学森时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的动力。”在此期间,他致力于设计一种洲际航天飞机,它是美国航天飞机的前身,并为后来X-20 Dyna-Soar的生产带来了灵感。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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钱学森娶了著名歌剧演员蒋英,蒋百里和他的妻子:日本护士SatôYato的女儿。蒋百里是国民党领导人蒋介石的军事战略家和顾问。钱学森夫妇于1947年9月14日在上海结婚,育有两个孩子;他们的儿子钱永刚(又称Yucon Tsien)于1948年10月13日出生在波士顿,而他们的女儿钱永珍则出生于1950年初,当时全家住在加州帕萨迪纳。 <br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱学森回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯·卡门的推荐下,钱学森成为加州理工学院喷气推进教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱学森获得永久居留许可,<br />
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=== Detention软禁 ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱学森是共产主义者,但是他的安全级别并没有被吊销。然而,1950年6月6日,他的安全级别被吊销,钱学森受到联邦调查局的审问。两周后,钱学森宣布他将辞去加州理工学院的工作,回到中国,那时的中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱学森与当时的海军副部长丹·A·金博尔(Dan A. Kimball)就这个问题进行了交谈,钱学森私下认识金博尔。钱学森告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱学森暗示,他仍然打算离开中国,并说“我是中国人。”,我不想制造杀死我同胞的武器,就这么简单。”金博尔接着说,“我不会让你回中国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱学森回中国的公司向美国海关透露,钱学森随身物品中有一些文件标有“机密”或“秘密”字样后,美国官员从帕萨迪纳的一个仓库里查获了这些文件。美国移民和归化局于8月25日发出逮捕令。钱学森称,这些加盖安全章的文件大多是自己写的,分类已经过时,并补充说,“有一些图纸和对数表等,可能被人误认为是代码。”材料中包括一本剪贴簿,上面有对那些被控从事原子间谍活动的人进行审判的新闻剪报,比如克劳斯·福克斯。随后对这些文件的检查表明,这些文件中没有任何机密材料。韦恩鲍姆的审判于8月30日开始,弗兰克·奥本海默和帕森斯都出庭作不利于他的证明。韦恩鲍姆被判犯有伪证罪,判处4年徒刑。钱学森于1950年9月6日被羁押问话 <br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱学森被宣布驱逐出境,未经允许不得离开洛杉矶县,实际上将他软禁起来。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
1947年,钱学森带着他的新娘从中国回来时,他在一份移民调查问卷中回答“不”,该问卷询问他是否曾是一个鼓吹以武力推翻美国政府的组织的成员。这一点,加上1938年的一份美国[CPUSA |共产党]]文件上面写着钱学森的名字,被用来证明钱学森是一个国家安全威胁。检方还引述了一次盘问环节,钱学森说,“我对中国人民有效忠义务”,如果美国和共产主义中国发生冲突,他“肯定不会”让美国政府替他决定效忠谁。<br />
During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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1951年4月26日,钱学森被宣布被驱逐出境,并禁止未经许可离开[加利福尼亚州洛杉矶市]],实际上对他实行了[[软禁]]。<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
在这期间,钱学森写了《工程控制论》,1954年由[[McGraw-Hill]]出版。这本书论述了稳定[[伺服机构]]的实践。在其18章中,它考虑了许多变量系统的非交互控制,[[微扰理论]]的控制设计,以及[[约翰.冯.诺依曼]]的[[误差控制]理论(第18章)。埃兹拉·克伦德尔回顾了《富兰克林学院学报》这本书,指出“对于那些对复杂[[控制系统]]整体理论感兴趣的人来说,很难夸大钱学森的书的价值。”显然,钱学森的方法主要是实用的,正如克伦德尔指出的,对于伺服机构,“通常的线性稳定性设计准则是不充分的,必须使用由问题的物理性质产生的其他准则。” <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱学森留在美国的金博尔副国务卿评论了他的遭遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China回到祖国 ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
钱学森成为美中两国长达五年秘密外交和谈判的对象。在此期间,钱学森一直生活在监视之下,有权任教,没有任何机密的研究任务。钱学森在被监禁期间得到加州理工学院同事的支持,包括总统[[李·杜布里奇]],后者飞往华盛顿为钱的案件辩护。加州理工学院指定律师格兰特·库伯 为钱辩护。<br />
He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科学技术大学的建立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭之外,钱学森在许多领域都有研究。他是系统学的创造者之一,在科技系统、体科学、工程科学、军事科学、社会科学、自然科学、地理、哲学、文学艺术、教育等领域做出了贡献。他在系统科学领域的概念、理论和方法上的进步包括对开放的复杂巨系统的研究。此外,他还帮助建立了中国复杂性科学学院。 <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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从20世纪80年代起,钱学森倡导对中医学、气功进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
回国后,钱学森在火箭科学领域开始了一段非常成功的职业生涯,这得益于他过去的成就以及中国政府对其核研究的支持而获得的声誉。他领导并最终成为中国导弹项目之父,该项目建造了[[东风(导弹)|东风弹道导弹]]和[[长征(火箭家族)|长征太空火箭]]。<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies中国核计划及其他研究 ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
1956年10月,任【【中华人民共和国国防部|国防部】】的【【中国航天科技集团公司|第五研究院】】所长,负责弹道导弹和核武器的研制。他是促成1964年10月16日“596”原子弹试验和1967年6月17日“6号试验”氢弹试验成功的总体努力的一部分。这是历史上最快的一次[核裂变|裂变]]到[[核聚变|聚变]]的发展,为32个月,相比之下,美国为86个月,苏联为75个月,使中国领先于[[法国]等西方大国获得了[[热核装置]]。<br />
Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱学森于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
钱学森是一位在美国陷入红色恐慌的著名科学家,这使他在[[毛泽东]时代及其后的时代有着相当大的影响力。钱学森最终升入党内,成为[中共中央委员会]委员。他加入了“中国航天计划——从构想到载人航天”计划。<br />
In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱学森被授予加州理工学院杰出校友奖。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友弗兰克·马博(Frank·Marble)的帮助下,在一个广为报道的仪式上把它带到了家中。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。 <br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱学森访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱学森“对美国政府失去了信任” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
1958年,他积极参与中国科学技术大学(USTC)的创建,并担任该校现代力学系主任若干年。 <br />
The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周和年度空间技术人物。这项认可不仅仅是一种荣誉,更是授予过去一年里对航空业影响最大的人。此外,那一年,中国中央电视台将钱学森评为中国最鼓舞人心的11位人物之一。 <br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
从20世纪80年代起,钱学森倡导对[[中医]]、[[气功]]进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会(一个国际系统工程荣誉学会),将钱学森位列四名荣誉会员之一。<br />
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== Later life 晚年生活==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱学森在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱学森》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
钱学森于1991年退休,安静地生活在北京,拒绝与西方人交谈。<br />
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In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
1979年,钱学森因其成就被加州理工学院授予“杰出校友奖”。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友的帮助下,在一个被广泛报道的仪式上把它带到了家里。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。<br />
Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯·S·A·科里(James S.A. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯·克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
中美关系正常化后,钱学森曾受美国航空航天研究所邀请访问美国,但他拒绝了邀请,因为他希望就被拘留一事正式道歉。在2002年发表的一篇回忆录中,马尔布尔说,他相信钱学森“对美国政府失去了信心”,但他“对美国人民一直怀有非常温暖的感情”。<br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
中国政府于1992年启动了载人航天计划,据报道,由于俄罗斯在太空的历史悠久,俄罗斯也给予了一些帮助。钱学森的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射神舟五号任务。钱学森老人能够在病床上通过电视观看中国首次载人航天任务。 <br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
2008年,他被评为航空周和年度空间技术人物。这一表彰并不是一种荣誉,而是授予在过去一年中被认为对航空业影响最大的人。[19][46]此外,当年中国中央电视台将钱学森评为中国最具启发性的十一位人物之一。<br />
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In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
2009年7月,国际系统工程荣誉学会欧米茄阿尔法协会(Omega Alpha Association)将钱学森(H.S.Tsien)命名为四位荣誉会员之一 <br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
2009年10月31日,钱学森在北京逝世,享年98岁 <br />
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A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
一部由张建亚执导、陈坤饰演钱学森的中国电影作品《钱学森》于2011年12月11日在亚洲和北美同时上映,并于2012年3月2日在中国上映。<br />
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== In popular culture在流行文化 ==<br />
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[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
科幻作家阿瑟·C·克拉克在1982年的小说《2010年:奥德赛二号》中,以他的名字命名了一艘中国太空船。科里的科幻小说系列《无边无际》也以他的名字命名了一艘火星飞船(麦克恩·雪森)。在1981年美国华裔科学家詹姆斯·克莱维尔(James Clavell)的小说《贵族之家》(Noble House)中,余博士是钱学森博士的虚构版本。<br />
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== Scientific papers 科学论文==<br />
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* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
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* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
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* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
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* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
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* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
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* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
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* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
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* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
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* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
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* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
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* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
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* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
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* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
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* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
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* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
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== Monographs专著 ==<br />
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* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
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** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
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* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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== See also参见 ==<br />
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{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
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* [[Aeronautics]]<br />
航空学<br />
* [[Engineering cybernetics]]<br />
工程控制论 <br />
* [[Jet Propulsion Laboratory]]<br />
喷气推进实验室 <br />
* [[Theodore von Kármán]]<br />
西奥多·冯·卡门 <br />
* [[Chien-Shiung Wu]]<br />
吴建雄<br />
* [[Ye Qisun]]<br />
叶企孙<br />
* [[Guo Yonghuai]]<br />
郭永怀<br />
Works cited<br />
<br />
引用作品<br />
<br />
* [[Hsue-Chu Tsien]]<br />
钱学森<br />
* [[McCarthyism]]<br />
麦卡锡主义<br />
* [[People's Liberation Army Rocket Force]]<br />
中国人民解放军火箭部队<br />
** [[Dongfeng (missile)]]<br />
东风导弹<br />
* [[Chinese space program]]<br />
中国航天计划 <br />
** [[Long March (rocket family)]]<br />
长征(火箭家族)<br />
* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
中国与大规模杀伤性武器|中国核计划 <br />
** [[596 (nuclear test)|Project 596]]<br />
596(核试验)|项目596<br />
** [[Test No. 6]]<br />
试验6<br />
* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
中国航天科技集团公司(原名国防部第五学院)<br />
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== References参考 ==<br />
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{{Reflist}}<br />
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;Works cited<br />
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{{refbegin}}<br />
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* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
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* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
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* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
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* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
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* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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{{refend}}<br />
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== External links外部链接 ==<br />
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{{Wikiquote}}<br />
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Category:1911 births<br />
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类别: 1911年出生<br />
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* [https://web.archive.org/web/20060502182903/http://www.astronautix.com/articles/china.htm China], Encyclopedia Astronautica<br />
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Category:2009 deaths<br />
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分类: 2009年死亡人数<br />
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* [http://www.cnn.com/2003/TECH/space/10/03/china.space.timeline/ CNN.com timeline of China space program]<br />
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Category:20th-century Chinese engineers<br />
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类别: 20世纪中国工程师<br />
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* {{cite web |url = http://archives.caltech.edu/news/tsien.html |title = In the News: The father of Chinese rocketry |author = <!--Staff writer(s); no by-line.--> |date = |website = Caltech |access-date = {{Date|2015-02-02|dmy}} }}<br />
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Category:20th-century Chinese mathematicians<br />
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范畴: 20世纪中国数学家<br />
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Category:21st-century Chinese engineers<br />
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类别: 21世纪中国工程师<br />
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{{Cybernetics}}<br />
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Category:21st-century Chinese mathematicians<br />
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范畴: 21世纪中国数学家<br />
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{{Jet Propulsion Laboratory}}<br />
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Category:Aerodynamicists<br />
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类别: 空气动力学家<br />
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{{CNSA space program}}<br />
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Category:Anti-communism in the United States<br />
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类别: 美国的反共产主义<br />
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Category:Cyberneticists<br />
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Category:Victims of McCarthyism<br />
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类别: 麦卡锡主义的受害者<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19382钱学森2020-11-29T14:48:08Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
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{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
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{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
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{{Infobox scientist<br />
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{{Infobox scientist<br />
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{信息盒科学家<br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name_lang = zh-Hans-CN<br />
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| native_name_lang = zh-Hans-CN<br />
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| native _ name _ lang = zh-Hans-CN<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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图片大小 =<br />
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| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
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| birth_date = <br />
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出生日期<br />
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| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
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| birth_place = Shanghai, Qing Empire<br />
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出生地: 上海,清朝<br />
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| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
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| death_date = <br />
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死亡日期<br />
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| death_place = [[Beijing]], [[China]]<br />
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| death_place = Beijing, China<br />
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死亡地点: 中国北京<br />
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| nationality = [[Nationality Law of China|Chinese]]<br />
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| nationality = Chinese<br />
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| 国籍 = 中国<br />
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| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
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| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
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工程控制论 | field = 航空航天工业奖<br />
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| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
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| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
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中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
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| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
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| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
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加利福尼亚理工学院国立交通大学<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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可压缩流体运动和反作用推进问题<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
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| thesis_year = 1939<br />
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| thesis_year = 1939<br />
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论文年份 = 1939<br />
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| doctoral_advisor = [[Theodore von Kármán]]<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_students = [[Cheng Chemin]]<br />
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| doctoral_students = Cheng Chemin<br />
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博士生 = Cheng Chemin<br />
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| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
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| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
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工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
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| 脚注 = <br />
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签名 = <br />
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| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
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| spouse = <br />
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配偶 =<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = 钱永刚 < br/> 钱永仁<br />
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| module = {{Chinese |child = yes<br />
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| module = {{Chinese |child = yes<br />
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{ Chinese | child = yes<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
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|l = Qian (surname) learning-forest<br />
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| l = 倩(姓)学林<br />
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|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
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|mi=<br />
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| mi =<br />
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}}<br />
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}}<br />
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'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
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Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
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钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
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During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
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在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全级别。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
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在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,乘坐美国总统邮轮克利夫兰号,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终促成了中国原子弹试验和氢弹试验的首次成功 ,使中国成为第五个核武器国家,并实现了历史上最快的裂变-聚变发展。此外,钱学森的工作还促成了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父”,绰号“火箭之王”。他是公认的两弹一星奠基人之一<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱学森当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他是曾参与中美航空航天事业的机械工程师钱学榘Hsue-Chu Tsien的表弟;他的侄子是2008年诺贝尔化学奖获得者钱永健Roger Y. Tsien。<br />
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== Early life and education 早期生活和教育经历==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱学森生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳是同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,主修铁路管理。他曾在南昌空军基地实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他被称为Hsue-Shen Tsien。他受到了美国工程教育方法的影响,尤其是对实验的重视。这与许多中国科学家所采用的当代方法形成了鲜明对比,后者强调理论元素,而不是“亲身体验”。钱学森的实验包括使用水银压力计绘制皮托管压力图。 <br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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西奥多·冯·卡门,钱学森的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
1936年的一天,他来找我咨询进一步的研究生学习。这是我们第一次见面。我抬起头来,注意到一个身材矮小、神情严肃的年轻人,他回答我的问题异常准确。他的敏锐和敏捷的思维给我留下了深刻的印象,我建议他去加州理工学院深造。钱学森同意了。他和我一起做了许多数学题。我发现他很有想象力,他有数学才能,他成功地把自然现象的物理图像形象化。即使是一个年轻的学生,他也帮助我理清了一些关于几个难题的想法。这样的天赋是我不常遇到的,钱和我成了亲密的同事。<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱学森被吸引了进来: “钱学森喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States 美国生涯==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希 普朗特(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯·卡门和钱学森为美国服务; 1956年后,钱学森为中国服务。钱保留的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯·卡门的博士生导师,而冯·卡门则是钱学森的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年来到加州理工学院后不久,钱学森就对弗兰克·马利纳(Frank Malina)、冯·卡门的其他学生以及他们的同伴(包括杰克·帕森斯)的火箭想法着迷。他和他的同学们一起,在加州理工学院的古根海姆航空实验室参与了与火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小组”的绰号。钱学森于1939年在加州理工学院获得博士学位 <br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱学森参与曼哈顿计划,帮助美国成功研制出第一颗原子弹。1943年,钱学森和他们火箭研究小组的另外两名成员起草了第一份文件,使用喷气推进实验室(JPL)这个名字,这最初是向陆军提出的一项针对德国V-2火箭发展导弹的建议。这促成了1944年的私人飞机A,以及后来的下士,WAC下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱学森作为一名拥有安全级别的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯·卡门在提到钱学森时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的动力。”在此期间,他致力于设计一种洲际航天飞机,它是美国航天飞机的前身,并为后来X-20 Dyna-Soar的生产带来了灵感。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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钱学森娶了著名歌剧演员蒋英,蒋百里和他的妻子:日本护士SatôYato的女儿。蒋百里是国民党领导人蒋介石的军事战略家和顾问。钱学森夫妇于1947年9月14日在上海结婚,育有两个孩子;他们的儿子钱永刚(又称Yucon Tsien)于1948年10月13日出生在波士顿,而他们的女儿钱永珍则出生于1950年初,当时全家住在加州帕萨迪纳。 <br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱学森回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯·卡门的推荐下,钱学森成为加州理工学院喷气推进教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱学森获得永久居留许可,<br />
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=== Detention软禁 ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱学森是共产主义者,但是他的安全级别并没有被吊销。然而,1950年6月6日,他的安全级别被吊销,钱学森受到联邦调查局的审问。两周后,钱学森宣布他将辞去加州理工学院的工作,回到中国,那时的中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱学森与当时的海军副部长丹·A·金博尔(Dan A. Kimball)就这个问题进行了交谈,钱学森私下认识金博尔。钱学森告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱学森暗示,他仍然打算离开中国,并说“我是中国人。”,我不想制造杀死我同胞的武器,就这么简单。”金博尔接着说,“我不会让你回中国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱学森回中国的公司向美国海关透露,钱学森随身物品中有一些文件标有“机密”或“秘密”字样后,美国官员从帕萨迪纳的一个仓库里查获了这些文件。美国移民和归化局于8月25日发出逮捕令。钱学森称,这些加盖安全章的文件大多是自己写的,分类已经过时,并补充说,“有一些图纸和对数表等,可能被人误认为是代码。”材料中包括一本剪贴簿,上面有对那些被控从事原子间谍活动的人进行审判的新闻剪报,比如克劳斯·福克斯。随后对这些文件的检查表明,这些文件中没有任何机密材料。韦恩鲍姆的审判于8月30日开始,弗兰克·奥本海默和帕森斯都出庭作不利于他的证明。韦恩鲍姆被判犯有伪证罪,判处4年徒刑。钱学森于1950年9月6日被羁押问话 <br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱学森被宣布驱逐出境,未经允许不得离开洛杉矶县,实际上将他软禁起来。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
1947年,钱学森带着他的新娘从中国回来时,他在一份移民调查问卷中回答“不”,该问卷询问他是否曾是一个鼓吹以武力推翻美国政府的组织的成员。这一点,加上1938年的一份美国[CPUSA |共产党]]文件上面写着钱学森的名字,被用来证明钱学森是一个国家安全威胁。检方还引述了一次盘问环节,钱学森说,“我对中国人民有效忠义务”,如果美国和共产主义中国发生冲突,他“肯定不会”让美国政府替他决定效忠谁。<br />
During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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1951年4月26日,钱学森被宣布被驱逐出境,并禁止未经许可离开[加利福尼亚州洛杉矶市]],实际上对他实行了[[软禁]]。<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
在这期间,钱学森写了《工程控制论》,1954年由[[McGraw-Hill]]出版。这本书论述了稳定[[伺服机构]]的实践。在其18章中,它考虑了许多变量系统的非交互控制,[[微扰理论]]的控制设计,以及[[约翰.冯.诺依曼]]的[[误差控制]理论(第18章)。埃兹拉·克伦德尔回顾了《富兰克林学院学报》这本书,指出“对于那些对复杂[[控制系统]]整体理论感兴趣的人来说,很难夸大钱学森的书的价值。”显然,钱学森的方法主要是实用的,正如克伦德尔指出的,对于伺服机构,“通常的线性稳定性设计准则是不充分的,必须使用由问题的物理性质产生的其他准则。” <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱学森留在美国的金博尔副国务卿评论了他的遭遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China回到祖国 ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
钱学森成为美中两国长达五年秘密外交和谈判的对象。在此期间,钱学森一直生活在监视之下,有权任教,没有任何机密的研究任务。钱学森在被监禁期间得到加州理工学院同事的支持,包括总统[[李·杜布里奇]],后者飞往华盛顿为钱的案件辩护。加州理工学院指定律师格兰特·库伯 为钱辩护。<br />
He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科学技术大学的建立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭之外,钱学森在许多领域都有研究。他是系统学的创造者之一,在科技系统、体科学、工程科学、军事科学、社会科学、自然科学、地理、哲学、文学艺术、教育等领域做出了贡献。他在系统科学领域的概念、理论和方法上的进步包括对开放的复杂巨系统的研究。此外,他还帮助建立了中国复杂性科学学院。 <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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从20世纪80年代起,钱学森倡导对中医学、气功进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
回国后,钱学森在火箭科学领域开始了一段非常成功的职业生涯,这得益于他过去的成就以及中国政府对其核研究的支持而获得的声誉。他领导并最终成为中国导弹项目之父,该项目建造了[[东风(导弹)|东风弹道导弹]]和[[长征(火箭家族)|长征太空火箭]]。<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies中国核计划及其他研究 ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
1956年10月,任【【中华人民共和国国防部|国防部】】的【【中国航天科技集团公司|第五研究院】】所长,负责弹道导弹和核武器的研制。他是促成1964年10月16日“596”原子弹试验和1967年6月17日“6号试验”氢弹试验成功的总体努力的一部分。这是历史上最快的一次[核裂变|裂变]]到[[核聚变|聚变]]的发展,为32个月,相比之下,美国为86个月,苏联为75个月,使中国领先于[[法国]等西方大国获得了[[热核装置]]。<br />
Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱学森于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
钱学森是一位在美国陷入红色恐慌的著名科学家,这使他在[[毛泽东]时代及其后的时代有着相当大的影响力。钱学森最终升入党内,成为[中共中央委员会]委员。他加入了“中国航天计划——从构想到载人航天”计划。<br />
In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱学森被授予加州理工学院杰出校友奖。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友弗兰克·马博(Frank·Marble)的帮助下,在一个广为报道的仪式上把它带到了家中。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。 <br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱学森访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱学森“对美国政府失去了信任” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
1958年,他积极参与中国科学技术大学(USTC)的创建,并担任该校现代力学系主任若干年。 <br />
The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周和年度空间技术人物。这项认可不仅仅是一种荣誉,更是授予过去一年里对航空业影响最大的人。此外,那一年,中国中央电视台将钱学森评为中国最鼓舞人心的11位人物之一。 <br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
从20世纪80年代起,钱学森倡导对[[中医]]、[[气功]]进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会(一个国际系统工程荣誉学会),将钱学森位列四名荣誉会员之一。<br />
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== Later life 晚年生活==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱学森在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱学森》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
钱学森于1991年退休,安静地生活在北京,拒绝与西方人交谈。<br />
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In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
1979年,钱学森因其成就被加州理工学院授予“杰出校友奖”。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友的帮助下,在一个被广泛报道的仪式上把它带到了家里。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。<br />
Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯·S·A·科里(James S.A. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯·克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
中美关系正常化后,钱学森曾受美国航空航天研究所邀请访问美国,但他拒绝了邀请,因为他希望就被拘留一事正式道歉。在2002年发表的一篇回忆录中,马尔布尔说,他相信钱学森“对美国政府失去了信心”,但他“对美国人民一直怀有非常温暖的感情”。<br />
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<br />
The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
中国政府于1992年启动了载人航天计划,据报道,由于俄罗斯在太空的历史悠久,俄罗斯也给予了一些帮助。钱学森的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射神舟五号任务。钱学森老人能够在病床上通过电视观看中国首次载人航天任务。 <br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
2008年,他被评为航空周和年度空间技术人物。这一表彰并不是一种荣誉,而是授予在过去一年中被认为对航空业影响最大的人。[19][46]此外,当年中国中央电视台将钱学森评为中国最具启发性的十一位人物之一。<br />
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<br />
In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
2009年7月,国际系统工程荣誉学会欧米茄阿尔法协会(Omega Alpha Association)将钱学森(H.S.Tsien)命名为四位荣誉会员之一 <br />
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<br />
On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
2009年10月31日,钱学森在北京逝世,享年98岁 <br />
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<br />
A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
一部由张建亚执导、陈坤饰演钱学森的中国电影作品《钱学森》于2011年12月11日在亚洲和北美同时上映,并于2012年3月2日在中国上映。<br />
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<br />
== In popular culture在流行文化 ==<br />
<br />
[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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<br />
<br />
== Scientific papers 科学论文==<br />
<br />
* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
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* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
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* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
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* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
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* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
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* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
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* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
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* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
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* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
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* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
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* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
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* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
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* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
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* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
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* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
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<br />
<br />
== Monographs专著 ==<br />
<br />
* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
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** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
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* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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== See also参见 ==<br />
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{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
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* [[Aeronautics]]<br />
航空学<br />
* [[Engineering cybernetics]]<br />
工程控制论 <br />
* [[Jet Propulsion Laboratory]]<br />
喷气推进实验室 <br />
* [[Theodore von Kármán]]<br />
西奥多·冯·卡门 <br />
* [[Chien-Shiung Wu]]<br />
吴建雄<br />
* [[Ye Qisun]]<br />
叶企孙<br />
* [[Guo Yonghuai]]<br />
郭永怀<br />
Works cited<br />
<br />
引用作品<br />
<br />
* [[Hsue-Chu Tsien]]<br />
钱学森<br />
* [[McCarthyism]]<br />
麦卡锡主义<br />
* [[People's Liberation Army Rocket Force]]<br />
中国人民解放军火箭部队<br />
** [[Dongfeng (missile)]]<br />
东风导弹<br />
* [[Chinese space program]]<br />
中国航天计划 <br />
** [[Long March (rocket family)]]<br />
长征(火箭家族)<br />
* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
中国与大规模杀伤性武器|中国核计划 <br />
** [[596 (nuclear test)|Project 596]]<br />
596(核试验)|项目596<br />
** [[Test No. 6]]<br />
试验6<br />
* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
中国航天科技集团公司(原名国防部第五学院)<br />
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== References参考 ==<br />
<br />
{{Reflist}}<br />
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;Works cited<br />
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{{refbegin}}<br />
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* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
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* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
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* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
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* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
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* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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{{refend}}<br />
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<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19301钱学森2020-11-27T14:48:58Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
<br />
{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
<br />
{{Infobox scientist<br />
<br />
{{Infobox scientist<br />
<br />
{信息盒科学家<br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native _ name _ lang = zh-Hans-CN<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image_size = <br />
<br />
| image_size = <br />
<br />
图片大小 =<br />
<br />
| caption = <br />
<br />
| caption = <br />
<br />
| caption =<br />
<br />
| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
<br />
| birth_date = <br />
<br />
出生日期<br />
<br />
| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
<br />
| birth_place = Shanghai, Qing Empire<br />
<br />
出生地: 上海,清朝<br />
<br />
| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
<br />
| death_date = <br />
<br />
死亡日期<br />
<br />
| death_place = [[Beijing]], [[China]]<br />
<br />
| death_place = Beijing, China<br />
<br />
死亡地点: 中国北京<br />
<br />
| nationality = [[Nationality Law of China|Chinese]]<br />
<br />
| nationality = Chinese<br />
<br />
| 国籍 = 中国<br />
<br />
| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
<br />
| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
<br />
工程控制论 | field = 航空航天工业奖<br />
<br />
| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
<br />
| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
<br />
中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
<br />
| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
<br />
| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
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加利福尼亚理工学院国立交通大学<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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可压缩流体运动和反作用推进问题<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
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| thesis_year = 1939<br />
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| thesis_year = 1939<br />
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论文年份 = 1939<br />
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| doctoral_advisor = [[Theodore von Kármán]]<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_students = [[Cheng Chemin]]<br />
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| doctoral_students = Cheng Chemin<br />
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博士生 = Cheng Chemin<br />
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| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
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| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
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工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
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签名 = <br />
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| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
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配偶 =<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = 钱永刚 < br/> 钱永仁<br />
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| module = {{Chinese |child = yes<br />
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| module = {{Chinese |child = yes<br />
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{ Chinese | child = yes<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
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|l = Qian (surname) learning-forest<br />
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| l = 倩(姓)学林<br />
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|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
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'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
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Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
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钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
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During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
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在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全级别。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
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在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,乘坐美国总统邮轮克利夫兰号,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终促成了中国原子弹试验和氢弹试验的首次成功 ,使中国成为第五个核武器国家,并实现了历史上最快的裂变-聚变发展。此外,钱学森的工作还促成了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父”,绰号“火箭之王”。他是公认的两弹一星奠基人之一<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱学森当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他是曾参与中美航空航天事业的机械工程师钱学榘Hsue-Chu Tsien的表弟;他的侄子是2008年诺贝尔化学奖获得者钱永健Roger Y. Tsien。<br />
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== Early life and education 早期生活和教育经历==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱学森生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳是同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,主修铁路管理。他曾在南昌空军基地实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他被称为Hsue-Shen Tsien。他受到了美国工程教育方法的影响,尤其是对实验的重视。这与许多中国科学家所采用的当代方法形成了鲜明对比,后者强调理论元素,而不是“亲身体验”。钱学森的实验包括使用水银压力计绘制皮托管压力图。 <br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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西奥多·冯·卡门,钱学森的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
1936年的一天,他来找我咨询进一步的研究生学习。这是我们第一次见面。我抬起头来,注意到一个身材矮小、神情严肃的年轻人,他回答我的问题异常准确。他的敏锐和敏捷的思维给我留下了深刻的印象,我建议他去加州理工学院深造。钱学森同意了。他和我一起做了许多数学题。我发现他很有想象力,他有数学才能,他成功地把自然现象的物理图像形象化。即使是一个年轻的学生,他也帮助我理清了一些关于几个难题的想法。这样的天赋是我不常遇到的,钱和我成了亲密的同事。<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱学森被吸引了进来: “钱学森喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States 美国生涯==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希 普朗特(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯·卡门和钱学森为美国服务; 1956年后,钱学森为中国服务。钱保留的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯·卡门的博士生导师,而冯·卡门则是钱学森的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年来到加州理工学院后不久,钱学森就对弗兰克·马利纳(Frank Malina)、冯·卡门的其他学生以及他们的同伴(包括杰克·帕森斯)的火箭想法着迷。他和他的同学们一起,在加州理工学院的古根海姆航空实验室参与了与火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小组”的绰号。钱学森于1939年在加州理工学院获得博士学位 <br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱学森参与曼哈顿计划,帮助美国成功研制出第一颗原子弹。1943年,钱学森和他们火箭研究小组的另外两名成员起草了第一份文件,使用喷气推进实验室(JPL)这个名字,这最初是向陆军提出的一项针对德国V-2火箭发展导弹的建议。这促成了1944年的私人飞机A,以及后来的下士,WAC下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱学森作为一名拥有安全级别的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯·卡门在提到钱学森时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的动力。”在此期间,他致力于设计一种洲际航天飞机,它是美国航天飞机的前身,并为后来X-20 Dyna-Soar的生产带来了灵感。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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钱学森娶了著名歌剧演员蒋英,蒋百里和他的妻子:日本护士SatôYato的女儿。蒋百里是国民党领导人蒋介石的军事战略家和顾问。钱学森夫妇于1947年9月14日在上海结婚,育有两个孩子;他们的儿子钱永刚(又称Yucon Tsien)于1948年10月13日出生在波士顿,而他们的女儿钱永珍则出生于1950年初,当时全家住在加州帕萨迪纳。 <br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱学森回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯·卡门的推荐下,钱学森成为加州理工学院喷气推进教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱学森获得永久居留许可,<br />
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=== Detention软禁 ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱学森是共产主义者,但是他的安全级别并没有被吊销。然而,1950年6月6日,他的安全级别被吊销,钱学森受到联邦调查局的审问。两周后,钱学森宣布他将辞去加州理工学院的工作,回到中国,那时的中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱学森与当时的海军副部长丹·A·金博尔(Dan A. Kimball)就这个问题进行了交谈,钱学森私下认识金博尔。钱学森告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱学森暗示,他仍然打算离开中国,并说“我是中国人。”,我不想制造杀死我同胞的武器,就这么简单。”金博尔接着说,“我不会让你回中国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱学森回中国的公司向美国海关透露,钱学森随身物品中有一些文件标有“机密”或“秘密”字样后,美国官员从帕萨迪纳的一个仓库里查获了这些文件。美国移民和归化局于8月25日发出逮捕令。钱学森称,这些加盖安全章的文件大多是自己写的,分类已经过时,并补充说,“有一些图纸和对数表等,可能被人误认为是代码。”材料中包括一本剪贴簿,上面有对那些被控从事原子间谍活动的人进行审判的新闻剪报,比如克劳斯·福克斯。随后对这些文件的检查表明,这些文件中没有任何机密材料。韦恩鲍姆的审判于8月30日开始,弗兰克·奥本海默和帕森斯都出庭作不利于他的证明。韦恩鲍姆被判犯有伪证罪,判处4年徒刑。钱学森于1950年9月6日被羁押问话 <br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱学森被宣布驱逐出境,未经允许不得离开洛杉矶县,实际上将他软禁起来。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
1947年,钱学森带着他的新娘从中国回来时,他在一份移民调查问卷中回答“不”,该问卷询问他是否曾是一个鼓吹以武力推翻美国政府的组织的成员。这一点,加上1938年的一份美国[CPUSA |共产党]]文件上面写着钱学森的名字,被用来证明钱学森是一个国家安全威胁。检方还引述了一次盘问环节,钱学森说,“我对中国人民有效忠义务”,如果美国和共产主义中国发生冲突,他“肯定不会”让美国政府替他决定效忠谁。<br />
During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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1951年4月26日,钱学森被宣布被驱逐出境,并禁止未经许可离开[加利福尼亚州洛杉矶市]],实际上对他实行了[[软禁]]。<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
在这期间,钱学森写了《工程控制论》,1954年由[[McGraw-Hill]]出版。这本书论述了稳定[[伺服机构]]的实践。在其18章中,它考虑了许多变量系统的非交互控制,[[微扰理论]]的控制设计,以及[[约翰.冯.诺依曼]]的[[误差控制]理论(第18章)。埃兹拉·克伦德尔回顾了《富兰克林学院学报》这本书,指出“对于那些对复杂[[控制系统]]整体理论感兴趣的人来说,很难夸大钱学森的书的价值。”显然,钱学森的方法主要是实用的,正如克伦德尔指出的,对于伺服机构,“通常的线性稳定性设计准则是不充分的,必须使用由问题的物理性质产生的其他准则。” <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱学森留在美国的金博尔副国务卿评论了他的遭遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China回到祖国 ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
钱学森成为美中两国长达五年秘密外交和谈判的对象。在此期间,钱学森一直生活在监视之下,有权任教,没有任何机密的研究任务。钱学森在被监禁期间得到加州理工学院同事的支持,包括总统[[李·杜布里奇]],后者飞往华盛顿为钱的案件辩护。加州理工学院指定律师格兰特·库伯 为钱辩护。<br />
He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科学技术大学的建立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭之外,钱学森在许多领域都有研究。他是系统学的创造者之一,在科技系统、体科学、工程科学、军事科学、社会科学、自然科学、地理、哲学、文学艺术、教育等领域做出了贡献。他在系统科学领域的概念、理论和方法上的进步包括对开放的复杂巨系统的研究。此外,他还帮助建立了中国复杂性科学学院。 <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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从20世纪80年代起,钱学森倡导对中医学、气功进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
回国后,钱学森在火箭科学领域开始了一段非常成功的职业生涯,这得益于他过去的成就以及中国政府对其核研究的支持而获得的声誉。他领导并最终成为中国导弹项目之父,该项目建造了[[东风(导弹)|东风弹道导弹]]和[[长征(火箭家族)|长征太空火箭]]。<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies中国核计划及其他研究 ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
1956年10月,任【【中华人民共和国国防部|国防部】】的【【中国航天科技集团公司|第五研究院】】所长,负责弹道导弹和核武器的研制。他是促成1964年10月16日“596”原子弹试验和1967年6月17日“6号试验”氢弹试验成功的总体努力的一部分。这是历史上最快的一次[核裂变|裂变]]到[[核聚变|聚变]]的发展,为32个月,相比之下,美国为86个月,苏联为75个月,使中国领先于[[法国]等西方大国获得了[[热核装置]]。<br />
Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱学森于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
钱学森是一位在美国陷入红色恐慌的著名科学家,这使他在[[毛泽东]时代及其后的时代有着相当大的影响力。钱学森最终升入党内,成为[中共中央委员会]委员。他加入了“中国航天计划——从构想到载人航天”计划。<br />
In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱学森被授予加州理工学院杰出校友奖。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友弗兰克·马博(Frank·Marble)的帮助下,在一个广为报道的仪式上把它带到了家中。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。 <br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱学森访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱学森“对美国政府失去了信任” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
1958年,他积极参与中国科学技术大学(USTC)的创建,并担任该校现代力学系主任若干年。 <br />
The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周和年度空间技术人物。这项认可不仅仅是一种荣誉,更是授予过去一年里对航空业影响最大的人。此外,那一年,中国中央电视台将钱学森评为中国最鼓舞人心的11位人物之一。 <br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
从20世纪80年代起,钱学森倡导对[[中医]]、[[气功]]进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会(一个国际系统工程荣誉学会),将钱学森位列四名荣誉会员之一。<br />
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== Later life 晚年生活==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱学森在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱学森》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
钱学森于1991年退休,安静地生活在北京,拒绝与西方人交谈。<br />
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In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
1979年,钱学森因其成就被加州理工学院授予“杰出校友奖”。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友的帮助下,在一个被广泛报道的仪式上把它带到了家里。此外,在20世纪90年代初,加州理工学院向他赠送了钱学森的研究成果文件柜。<br />
Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯·S·A·科里(James S.A. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯·克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
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In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
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A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
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== In popular culture在流行文化 ==<br />
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[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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== Scientific papers 科学论文==<br />
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* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
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* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
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* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
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* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
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* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
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* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
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* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
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* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
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* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
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* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
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* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
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* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
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* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
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* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
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* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
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== Monographs专著 ==<br />
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* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
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** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
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* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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== See also参见 ==<br />
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{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
<br />
* [[Aeronautics]]<br />
航空学<br />
* [[Engineering cybernetics]]<br />
工程控制论 <br />
* [[Jet Propulsion Laboratory]]<br />
喷气推进实验室 <br />
* [[Theodore von Kármán]]<br />
西奥多·冯·卡门 <br />
* [[Chien-Shiung Wu]]<br />
吴建雄<br />
* [[Ye Qisun]]<br />
叶企孙<br />
* [[Guo Yonghuai]]<br />
郭永怀<br />
Works cited<br />
<br />
引用作品<br />
<br />
* [[Hsue-Chu Tsien]]<br />
钱学森<br />
* [[McCarthyism]]<br />
麦卡锡主义<br />
* [[People's Liberation Army Rocket Force]]<br />
中国人民解放军火箭部队<br />
** [[Dongfeng (missile)]]<br />
东风导弹<br />
* [[Chinese space program]]<br />
中国航天计划 <br />
** [[Long March (rocket family)]]<br />
长征(火箭家族)<br />
* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
中国与大规模杀伤性武器|中国核计划 <br />
** [[596 (nuclear test)|Project 596]]<br />
596(核试验)|项目596<br />
** [[Test No. 6]]<br />
试验6<br />
* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
中国航天科技集团公司(原名国防部第五学院)<br />
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== References参考 ==<br />
<br />
{{Reflist}}<br />
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;Works cited<br />
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{{refbegin}}<br />
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* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
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* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
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* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
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* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
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* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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{{refend}}<br />
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* [https://web.archive.org/web/20060502182903/http://www.astronautix.com/articles/china.htm China], Encyclopedia Astronautica<br />
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* {{cite web |url = http://archives.caltech.edu/news/tsien.html |title = In the News: The father of Chinese rocketry |author = <!--Staff writer(s); no by-line.--> |date = |website = Caltech |access-date = {{Date|2015-02-02|dmy}} }}<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19300钱学森2020-11-27T13:11:38Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
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{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
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{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
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{{Infobox scientist<br />
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{{Infobox scientist<br />
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{信息盒科学家<br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name_lang = zh-Hans-CN<br />
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| native_name_lang = zh-Hans-CN<br />
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| native _ name _ lang = zh-Hans-CN<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
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| birth_date = <br />
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出生日期<br />
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| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
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| birth_place = Shanghai, Qing Empire<br />
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出生地: 上海,清朝<br />
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| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
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死亡日期<br />
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| death_place = [[Beijing]], [[China]]<br />
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| death_place = Beijing, China<br />
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死亡地点: 中国北京<br />
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| nationality = [[Nationality Law of China|Chinese]]<br />
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| nationality = Chinese<br />
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| 国籍 = 中国<br />
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| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
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| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
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工程控制论 | field = 航空航天工业奖<br />
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| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
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| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
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中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
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| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
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| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
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加利福尼亚理工学院国立交通大学<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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可压缩流体运动和反作用推进问题<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
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| thesis_year = 1939<br />
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| thesis_year = 1939<br />
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论文年份 = 1939<br />
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| doctoral_advisor = [[Theodore von Kármán]]<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_students = [[Cheng Chemin]]<br />
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| doctoral_students = Cheng Chemin<br />
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博士生 = Cheng Chemin<br />
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| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
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| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
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工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
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签名 = <br />
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| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
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配偶 =<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = 钱永刚 < br/> 钱永仁<br />
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| module = {{Chinese |child = yes<br />
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| module = {{Chinese |child = yes<br />
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{ Chinese | child = yes<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
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|l = Qian (surname) learning-forest<br />
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| l = 倩(姓)学林<br />
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|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
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|mi=<br />
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}}<br />
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'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
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Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
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钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
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During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
<br />
在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全级别。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
<br />
在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,乘坐美国总统邮轮克利夫兰号,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终促成了中国原子弹试验和氢弹试验的首次成功 ,使中国成为第五个核武器国家,并实现了历史上最快的裂变-聚变发展。此外,钱学森的工作还促成了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父”,绰号“火箭之王”。他是公认的两弹一星奠基人之一<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱学森当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他是曾参与中美航空航天事业的机械工程师钱学榘Hsue-Chu Tsien的表弟;他的侄子是2008年诺贝尔化学奖获得者钱永健Roger Y. Tsien。<br />
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== Early life and education 早期生活和教育经历==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱学森生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳是同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,主修铁路管理。他曾在南昌空军基地实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他被称为Hsue-Shen Tsien。他受到了美国工程教育方法的影响,尤其是对实验的重视。这与许多中国科学家所采用的当代方法形成了鲜明对比,后者强调理论元素,而不是“亲身体验”。钱学森的实验包括使用水银压力计绘制皮托管压力图。 <br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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西奥多·冯·卡门,钱学森的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
1936年的一天,他来找我咨询进一步的研究生学习。这是我们第一次见面。我抬起头来,注意到一个身材矮小、神情严肃的年轻人,他回答我的问题异常准确。他的敏锐和敏捷的思维给我留下了深刻的印象,我建议他去加州理工学院深造。钱学森同意了。他和我一起做了许多数学题。我发现他很有想象力,他有数学才能,他成功地把自然现象的物理图像形象化。即使是一个年轻的学生,他也帮助我理清了一些关于几个难题的想法。这样的天赋是我不常遇到的,钱和我成了亲密的同事。<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱学森被吸引了进来: “钱学森喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States 美国生涯==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希 普朗特(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯·卡门和钱学森为美国服务; 1956年后,钱学森为中国服务。钱保留的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯·卡门的博士生导师,而冯·卡门则是钱学森的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年来到加州理工学院后不久,钱学森就对弗兰克·马利纳(Frank Malina)、冯·卡门的其他学生以及他们的同伴(包括杰克·帕森斯)的火箭想法着迷。他和他的同学们一起,在加州理工学院的古根海姆航空实验室参与了与火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小组”的绰号。钱学森于1939年在加州理工学院获得博士学位 <br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱学森参与曼哈顿计划,帮助美国成功研制出第一颗原子弹。1943年,钱学森和他们火箭研究小组的另外两名成员起草了第一份文件,使用喷气推进实验室(JPL)这个名字,这最初是向陆军提出的一项针对德国V-2火箭发展导弹的建议。这促成了1944年的私人飞机A,以及后来的下士,WAC下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱学森作为一名拥有安全级别的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯·卡门在提到钱学森时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的动力。”在此期间,他致力于设计一种洲际航天飞机,它是美国航天飞机的前身,并为后来X-20 Dyna-Soar的生产带来了灵感。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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钱学森娶了著名歌剧演员蒋英,蒋百里和他的妻子:日本护士SatôYato的女儿。蒋百里是国民党领导人蒋介石的军事战略家和顾问。钱学森夫妇于1947年9月14日在上海结婚,育有两个孩子;他们的儿子钱永刚(又称Yucon Tsien)于1948年10月13日出生在波士顿,而他们的女儿钱永珍则出生于1950年初,当时全家住在加州帕萨迪纳。 <br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱学森回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯·卡门的推荐下,钱学森成为加州理工学院喷气推进教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱学森获得永久居留许可,<br />
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=== Detention软禁 ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱学森是共产主义者,但是他的安全级别并没有被吊销。然而,1950年6月6日,他的安全级别被吊销,钱学森受到联邦调查局的审问。两周后,钱学森宣布他将辞去加州理工学院的工作,回到中国,那时的中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱学森与当时的海军副部长丹·A·金博尔(Dan A. Kimball)就这个问题进行了交谈,钱学森私下认识金博尔。钱学森告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱学森暗示,他仍然打算离开中国,并说“我是中国人。”,我不想制造杀死我同胞的武器,就这么简单。”金博尔接着说,“我不会让你回中国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱学森回中国的公司向美国海关透露,钱学森随身物品中有一些文件标有“机密”或“秘密”字样后,美国官员从帕萨迪纳的一个仓库里查获了这些文件。美国移民和归化局于8月25日发出逮捕令。钱学森称,这些加盖安全章的文件大多是自己写的,分类已经过时,并补充说,“有一些图纸和对数表等,可能被人误认为是代码。”材料中包括一本剪贴簿,上面有对那些被控从事原子间谍活动的人进行审判的新闻剪报,比如克劳斯·福克斯。随后对这些文件的检查表明,这些文件中没有任何机密材料。韦恩鲍姆的审判于8月30日开始,弗兰克·奥本海默和帕森斯都出庭作不利于他的证明。韦恩鲍姆被判犯有伪证罪,判处4年徒刑。钱学森于1950年9月6日被羁押问话 <br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱学森被宣布驱逐出境,未经允许不得离开洛杉矶县,实际上将他软禁起来。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
1947年,钱学森带着他的新娘从中国回来时,他在一份移民调查问卷中回答“不”,该问卷询问他是否曾是一个鼓吹以武力推翻美国政府的组织的成员。这一点,加上1938年的一份美国[CPUSA |共产党]]文件上面写着钱学森的名字,被用来证明钱学森是一个国家安全威胁。检方还引述了一次盘问环节,钱学森说,“我对中国人民有效忠义务”,如果美国和共产主义中国发生冲突,他“肯定不会”让美国政府替他决定效忠谁。<br />
During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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1951年4月26日,钱学森被宣布被驱逐出境,并禁止未经许可离开[加利福尼亚州洛杉矶市]],实际上对他实行了[[软禁]]。<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
在这期间,钱学森写了《工程控制论》,1954年由[[McGraw-Hill]]出版。这本书论述了稳定[[伺服机构]]的实践。在其18章中,它考虑了许多变量系统的非交互控制,[[微扰理论]]的控制设计,以及[[约翰.冯.诺依曼]]的[[误差控制]理论(第18章)。埃兹拉·克伦德尔回顾了《富兰克林学院学报》这本书,指出“对于那些对复杂[[控制系统]]整体理论感兴趣的人来说,很难夸大钱学森的书的价值。”显然,钱学森的方法主要是实用的,正如克伦德尔指出的,对于伺服机构,“通常的线性稳定性设计准则是不充分的,必须使用由问题的物理性质产生的其他准则。” <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱学森留在美国的金博尔副国务卿评论了他的遭遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China回到祖国 ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
钱学森成为美中两国长达五年秘密外交和谈判的对象。在此期间,钱学森一直生活在监视之下,有权任教,没有任何机密的研究任务。钱学森在被监禁期间得到加州理工学院同事的支持,包括总统[[李·杜布里奇]],后者飞往华盛顿为钱的案件辩护。加州理工学院指定律师格兰特·库伯 为钱辩护。<br />
He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科学技术大学的建立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭之外,钱学森在许多领域都有研究。他是系统学的创造者之一,在科技系统、体科学、工程科学、军事科学、社会科学、自然科学、地理、哲学、文学艺术、教育等领域做出了贡献。他在系统科学领域的概念、理论和方法上的进步包括对开放的复杂巨系统的研究。此外,他还帮助建立了中国复杂性科学学院。 <br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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从20世纪80年代起,钱学森倡导对中医学、气功进行科学研究,提出“人体特殊功能”的概念。他特别鼓励科学家积累气功的观测数据,以便将来建立科学理论。 <br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
回国后,钱学森在火箭科学领域开始了一段非常成功的职业生涯,这得益于他过去的成就以及中国政府对其核研究的支持而获得的声誉。他领导并最终成为中国导弹项目之父,该项目建造了[[东风(导弹)|东风弹道导弹]]和[[长征(火箭家族)|长征太空火箭]]。<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies中国核计划及其他研究 ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
1956年10月,任【【中华人民共和国国防部|国防部】】的【【中国航天科技集团公司|第五研究院】】所长,负责弹道导弹和核武器的研制。他是促成1964年10月16日“596”原子弹试验和1967年6月17日“6号试验”氢弹试验成功的总体努力的一部分。这是历史上最快的一次[核裂变|裂变]]到[[核聚变|聚变]]的发展,为32个月,相比之下,美国为86个月,苏联为75个月,使中国领先于[[法国]等西方大国获得了[[热核装置]]。<br />
Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱学森于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
钱学森是一位在美国陷入红色恐慌的著名科学家,这使他在[[毛泽东]时代及其后的时代有着相当大的影响力。钱学森最终升入党内,成为[中共中央委员会]委员。他加入了“中国航天计划——从构想到载人航天”计划。<br />
In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱学森被授予加州理工学院杰出校友奖。钱学森最终从加州理工学院获得了这个奖项,并在他的朋友弗兰克·马博(Frank·Marble)的帮助下,在一个广为报道的仪式上把它带到了家中。此外,在20世纪90年代初,加州理工学院向他提供了钱学森的研究成果文件柜。 <br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱“对美国政府失去了信心” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周刊和航天技术年度人物。这种认可并不是一种荣誉,而是给予那些在过去一年中被认为对航空业影响最大的人。此外,那一年,中国中央电视台将钱列为中国十一个最鼓舞人心的人物之一。<br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会,一个国际系统工程荣誉学会,命名为钱(钱)四名荣誉会员之一。<br />
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== Later life ==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
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In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯 · s · a · 科里(James s. a. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯 · 克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
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In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
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A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
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== In popular culture ==<br />
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[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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== Scientific papers ==<br />
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* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
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* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
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* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
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* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
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* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
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* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
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* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
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* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
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* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
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* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
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* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
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* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
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* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
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* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
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* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
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== Monographs ==<br />
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* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
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** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
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* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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== See also ==<br />
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{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
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* [[Aeronautics]]<br />
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* [[Engineering cybernetics]]<br />
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* [[Jet Propulsion Laboratory]]<br />
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* [[Theodore von Kármán]]<br />
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* [[Chien-Shiung Wu]]<br />
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* [[Ye Qisun]]<br />
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* [[Guo Yonghuai]]<br />
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Works cited<br />
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引用作品<br />
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* [[Hsue-Chu Tsien]]<br />
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* [[McCarthyism]]<br />
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* [[People's Liberation Army Rocket Force]]<br />
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** [[Dongfeng (missile)]]<br />
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* [[Chinese space program]]<br />
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** [[Long March (rocket family)]]<br />
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* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
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** [[596 (nuclear test)|Project 596]]<br />
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** [[Test No. 6]]<br />
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* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
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== References ==<br />
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{{Reflist}}<br />
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;Works cited<br />
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{{refbegin}}<br />
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* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
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* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
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* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
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* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
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* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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{{refend}}<br />
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<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19276钱学森2020-11-27T06:54:19Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
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{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
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{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
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{{Infobox scientist<br />
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{{Infobox scientist<br />
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{信息盒科学家<br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name = 钱学森<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native_name_lang = zh-Hans-CN<br />
<br />
| native _ name _ lang = zh-Hans-CN<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image = Tsien Hsue-shen.jpg<br />
<br />
| image_size = <br />
<br />
| image_size = <br />
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图片大小 =<br />
<br />
| caption = <br />
<br />
| caption = <br />
<br />
| caption =<br />
<br />
| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
<br />
| birth_date = <br />
<br />
出生日期<br />
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| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
<br />
| birth_place = Shanghai, Qing Empire<br />
<br />
出生地: 上海,清朝<br />
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| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
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| death_date = <br />
<br />
死亡日期<br />
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| death_place = [[Beijing]], [[China]]<br />
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| death_place = Beijing, China<br />
<br />
死亡地点: 中国北京<br />
<br />
| nationality = [[Nationality Law of China|Chinese]]<br />
<br />
| nationality = Chinese<br />
<br />
| 国籍 = 中国<br />
<br />
| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
<br />
| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
<br />
工程控制论 | field = 航空航天工业奖<br />
<br />
| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
<br />
| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
<br />
中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
<br />
| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
<br />
| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
<br />
加利福尼亚理工学院国立交通大学<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
<br />
| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
<br />
可压缩流体运动和反作用推进问题<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
<br />
| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
<br />
Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
<br />
| thesis_year = 1939<br />
<br />
| thesis_year = 1939<br />
<br />
论文年份 = 1939<br />
<br />
| doctoral_advisor = [[Theodore von Kármán]]<br />
<br />
| doctoral_advisor = Theodore von Kármán<br />
<br />
| doctoral_advisor = Theodore von Kármán<br />
<br />
| doctoral_students = [[Cheng Chemin]]<br />
<br />
| doctoral_students = Cheng Chemin<br />
<br />
博士生 = Cheng Chemin<br />
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| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
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| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
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工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
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| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
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配偶 =<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = 钱永刚 < br/> 钱永仁<br />
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| module = {{Chinese |child = yes<br />
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| module = {{Chinese |child = yes<br />
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{ Chinese | child = yes<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
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|l = Qian (surname) learning-forest<br />
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| l = 倩(姓)学林<br />
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|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
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'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
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Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
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钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
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During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
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在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全级别。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
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在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,乘坐美国总统邮轮克利夫兰号,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终促成了中国原子弹试验和氢弹试验的首次成功 ,使中国成为第五个核武器国家,并实现了历史上最快的裂变-聚变发展。此外,钱学森的工作还促成了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父”,绰号“火箭之王”。他是公认的两弹一星奠基人之一<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱学森当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他是曾参与中美航空航天事业的机械工程师钱学榘Hsue-Chu Tsien的表弟;他的侄子是2008年诺贝尔化学奖获得者钱永健Roger Y. Tsien。<br />
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== Early life and education 早期生活和教育经历==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱学森生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳是同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,主修铁路管理。他曾在南昌空军基地实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他被称为Hsue-Shen Tsien。他受到了美国工程教育方法的影响,尤其是对实验的重视。这与许多中国科学家所采用的当代方法形成了鲜明对比,后者强调理论元素,而不是“亲身体验”。钱学森的实验包括使用水银压力计绘制皮托管压力图。 <br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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西奥多·冯·卡门,钱学森的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
1936年的一天,他来找我咨询进一步的研究生学习。这是我们第一次见面。我抬起头来,注意到一个身材矮小、神情严肃的年轻人,他回答我的问题异常准确。他的敏锐和敏捷的思维给我留下了深刻的印象,我建议他去加州理工学院深造。钱学森同意了。他和我一起做了许多数学题。我发现他很有想象力,他有数学才能,他成功地把自然现象的物理图像形象化。即使是一个年轻的学生,他也帮助我理清了一些关于几个难题的想法。这样的天赋是我不常遇到的,钱和我成了亲密的同事。<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱学森被吸引了进来: “钱学森喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States 美国生涯==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希 普朗特(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯·卡门和钱学森为美国服务; 1956年后,钱学森为中国服务。钱保留的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯·卡门的博士生导师,而冯·卡门则是钱学森的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年来到加州理工学院后不久,钱学森就对弗兰克·马利纳(Frank Malina)、冯·卡门的其他学生以及他们的同伴(包括杰克·帕森斯)的火箭想法着迷。他和他的同学们一起,在加州理工学院的古根海姆航空实验室参与了与火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小组”的绰号。钱学森于1939年在加州理工学院获得博士学位 <br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱学森参与曼哈顿计划,帮助美国成功研制出第一颗原子弹。1943年,钱学森和他们火箭研究小组的另外两名成员起草了第一份文件,使用喷气推进实验室(JPL)这个名字,这最初是向陆军提出的一项针对德国V-2火箭发展导弹的建议。这促成了1944年的私人飞机A,以及后来的下士,WAC下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱学森作为一名拥有安全级别的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯·卡门在提到钱学森时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的动力。”在此期间,他致力于设计一种洲际航天飞机,它是美国航天飞机的前身,并为后来X-20 Dyna-Soar的生产带来了灵感。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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钱学森娶了著名歌剧演员蒋英,蒋百里和他的妻子:日本护士SatôYato的女儿。蒋百里是国民党领导人蒋介石的军事战略家和顾问。钱学森夫妇于1947年9月14日在上海结婚,育有两个孩子;他们的儿子钱永刚(又称Yucon Tsien)于1948年10月13日出生在波士顿,而他们的女儿钱永珍则出生于1950年初,当时全家住在加州帕萨迪纳。 <br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱学森回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯·卡门的推荐下,钱学森成为加州理工学院喷气推进教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱学森获得永久居留许可,<br />
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=== Detention ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱存训是共产主义者的指控,但是他的安全许可并没有被停职。然而,1950年6月6日,他的安全许可被撤销,钱存训受到联邦调查局的审问。两周后,钱存训宣布他将辞去加州理工学院的工作,回到中国,那时中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱存训与当时的海军副部长丹 · a · 金博尔(Dan a. Kimball)就这个问题进行了交谈,钱存训私下认识金博尔。钱存训告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱存训暗示,他仍然打算离开中国,并说“我是中国人。”。我不想制造杀死我同胞的武器。就是这么简单。”金博尔接着说,“我不会让你出国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱存训返回中国的公司向美国海关透露,钱存训的一些文件被标记为“秘密”或“机密”之后,美国官员从帕萨迪纳市的一个仓库中没收了这些文件。8月25日,美国美国移民及归化局发出了对钱存训的逮捕令。钱存训声称,这些加了安全标签的文件大部分是他自己写的,分类已经过时,并补充说,“里面有一些绘图和对数表等,有人可能把它们误认为代码。”这些材料包括一本剪贴簿,里面有关于那些被指控从事原子间谍活动的人受审的剪报,比如克劳斯 · 福克斯。随后对这些文件的检查表明,其中没有任何机密材料。对 Weinbaum 的审判于8月30日开始,Frank Oppenheimer 和 Parsons 都作了不利于他的证词。温鲍姆因伪证罪被判刑四年。钱存训于1950年9月6日被拘留审问<br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱存训被宣布被驱逐出境,未经许可不得离开洛杉矶县,实际上将他软禁在家。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
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During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱留在美国的金博尔副国务卿评论了他的待遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科技大学的成立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭技术,钱在许多领域的研究存在。他是系统科学的创始人之一,在科学技术体系、躯体科学、工程科学、军事科学、社会科学、自然科学、地理学、哲学、文学艺术和教育等方面做出了贡献。他在系统科学领域的概念、理论和方法方面的进展包括研究开放的复杂巨系统。此外,他还帮助建立了中国复杂性科学学派。<br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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自20世纪80年代以来,钱一直倡导对中医气功的科学研究,倡导“人体特殊功能”的概念。他特别鼓励科学家们积累气功的观测数据,以便建立未来的科学理论。<br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
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In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱获得加州理工学院杰出校友奖。钱最终从加州理工学院获得了这个奖项,在朋友弗兰克 · 马布尔的帮助下,钱在一个被广泛报道的仪式上把它带回了家。此外,在20世纪90年代早期,加州理工学院向他提供了装有钱研究成果的文件柜。<br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱“对美国政府失去了信心” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周刊和航天技术年度人物。这种认可并不是一种荣誉,而是给予那些在过去一年中被认为对航空业影响最大的人。此外,那一年,中国中央电视台将钱列为中国十一个最鼓舞人心的人物之一。<br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会,一个国际系统工程荣誉学会,命名为钱(钱)四名荣誉会员之一。<br />
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== Later life ==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
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In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯 · s · a · 科里(James s. a. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯 · 克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
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In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
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A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
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== In popular culture ==<br />
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[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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== Scientific papers ==<br />
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* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
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* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
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* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
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* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
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* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
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* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
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* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
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* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
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* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
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* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
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* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
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* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
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* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
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* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
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* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
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== Monographs ==<br />
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* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
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** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
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* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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== See also ==<br />
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{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
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* [[Aeronautics]]<br />
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* [[Engineering cybernetics]]<br />
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* [[Jet Propulsion Laboratory]]<br />
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* [[Theodore von Kármán]]<br />
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* [[Chien-Shiung Wu]]<br />
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* [[Ye Qisun]]<br />
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* [[Guo Yonghuai]]<br />
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Works cited<br />
<br />
引用作品<br />
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* [[Hsue-Chu Tsien]]<br />
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* [[McCarthyism]]<br />
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* [[People's Liberation Army Rocket Force]]<br />
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** [[Dongfeng (missile)]]<br />
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* [[Chinese space program]]<br />
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** [[Long March (rocket family)]]<br />
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* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
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** [[596 (nuclear test)|Project 596]]<br />
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** [[Test No. 6]]<br />
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* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
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== References ==<br />
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{{Reflist}}<br />
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;Works cited<br />
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{{refbegin}}<br />
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* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
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* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
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* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
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* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
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* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E9%92%B1%E5%AD%A6%E6%A3%AE&diff=19264钱学森2020-11-26T15:01:44Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
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{{Redirect|Hsue-Shen Tsien|the 2012 biographical film|Hsue-shen Tsien (film)}}<br />
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{{family name hatnote|[[Qian (surname)|Qian (Tsien)]]|lang=Chinese}}<br />
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{{Infobox scientist<br />
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{{Infobox scientist<br />
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{信息盒科学家<br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| name = Qian Xuesen<br /><small>Hsue-Shen Tsien</small><br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name = 钱学森<br />
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| native_name_lang = zh-Hans-CN<br />
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| native_name_lang = zh-Hans-CN<br />
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| native _ name _ lang = zh-Hans-CN<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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| image = Tsien Hsue-shen.jpg<br />
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| birth_date = {{Birth date|1911|12|11|df=yes}}<br />
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出生日期<br />
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| birth_place = [[Shanghai]], [[Qing dynasty|Qing Empire]]<br />
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| birth_place = Shanghai, Qing Empire<br />
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出生地: 上海,清朝<br />
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| death_date = {{Death date and age|2009|10|31|1911|12|11|df=yes}}<br />
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死亡日期<br />
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| death_place = [[Beijing]], [[China]]<br />
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| death_place = Beijing, China<br />
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死亡地点: 中国北京<br />
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| nationality = [[Nationality Law of China|Chinese]]<br />
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| nationality = Chinese<br />
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| 国籍 = 中国<br />
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| field = [[Aerospace engineering]]<br/>[[Aeronautics]]<br />[[Engineering cybernetics]]<br />
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| field = Aerospace engineering<br/>Aeronautics<br />Engineering cybernetics<br />
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工程控制论 | field = 航空航天工业奖<br />
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| work_institutions = [[California Institute of Technology]] (professor) and [[Jet Propulsion Laboratory]] (co-founder)<br />[[Massachusetts Institute of Technology]] (professor)<br />[[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense, PRC]] (first director)<br />Institute of Mechanics of the [[Chinese Academy of Sciences]] (first director)<br />Commission of Science and Technology for National Defense of the [[People's Liberation Army|PLA]] (vice-director)<br />
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| work_institutions = California Institute of Technology (professor) and Jet Propulsion Laboratory (co-founder)<br />Massachusetts Institute of Technology (professor)<br />Fifth Academy of the Ministry of National Defense, PRC (first director)<br />Institute of Mechanics of the Chinese Academy of Sciences (first director)<br />Commission of Science and Technology for National Defense of the PLA (vice-director)<br />
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中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院力学研究所(第一所)中国科学院国防科学技术委员会(第一所)中国科学院国防科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第一所)中国科学技术委员会(第二所)中国科学技术委员会(第二所)中国科<br />
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| alma_mater = [[Shanghai Jiaotong University|National Chiao Tung University]]<br />{{nowrap|[[Massachusetts Institute of Technology]]}}<br />[[California Institute of Technology]]<br />
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| alma_mater = National Chiao Tung University<br /><br />California Institute of Technology<br />
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加利福尼亚理工学院国立交通大学<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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| thesis_title = Problems in motion of compressible fluids and reaction propulsion<br />
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可压缩流体运动和反作用推进问题<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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| thesis_url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646<br />
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Http://resolver.caltech.edu/caltechetd:etd-01122004-105646<br />
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| thesis_year = 1939<br />
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| thesis_year = 1939<br />
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论文年份 = 1939<br />
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| doctoral_advisor = [[Theodore von Kármán]]<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_advisor = Theodore von Kármán<br />
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| doctoral_students = [[Cheng Chemin]]<br />
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| doctoral_students = Cheng Chemin<br />
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博士生 = Cheng Chemin<br />
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| known_for = Co-founder of the [[Jet Propulsion Laboratory]]<br />Founder of [[engineering cybernetics]]<br />Father of [[Chinese space program]] <br /> Work on the [[Manhattan Project]]<br />
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| known_for = Co-founder of the Jet Propulsion Laboratory<br />Founder of engineering cybernetics<br />Father of Chinese space program <br /> Work on the Manhattan Project<br />
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工程控制论创始人中国太空计划之父曼哈顿计划工作喷气推进实验室<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| prizes = Distinguished Alumni Award from Caltech (1979)<br />
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| 奖金 = 加州理工学院杰出校友奖(1979年)<br />
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| spouse = {{Marriage|[[Jiang Ying (musician)|Jiang Ying]]|1947}}<br />
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配偶 =<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = Qian Yonggang<br />Qian Yungjen<br />
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| children = 钱永刚 < br/> 钱永仁<br />
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| module = {{Chinese |child = yes<br />
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| module = {{Chinese |child = yes<br />
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{ Chinese | child = yes<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|s = 钱学森<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|p = Qián Xuésēn<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|t = 錢學森<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|w = Ch'ien Hsüeh-sen<br />
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|l = [[Qian (surname)]] [[learning]]-[[forest]]<br />
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|l = Qian (surname) learning-forest<br />
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| l = 倩(姓)学林<br />
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|mi={{IPAc-cmn|q|ian|2|-|xue|2|.|s|en|1}}<br />
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'''Qian Xuesen''', or '''Hsue-Shen Tsien''' ({{zh |s = 钱学森 }}; 11 December 1911 – 31 October 2009), was a Chinese [[mathematician]], [[cyberneticist]], [[aerospace engineer]], and [[physicist]] who made significant contributions to the field of [[aerodynamics]] and established [[engineering cybernetics]]. Recruited from [[MIT]], he joined [[Theodore von Kármán]]'s group at [[Caltech]].<ref>{{cite web |url = https://history.nasa.gov/biost-z.html |title = Biographies of Aerospace Officials and Policymakers |publisher = NASA |access-date = {{Date|2015-02-02|dmy}} }}</ref> During [[WWII]], he was involved in the [[Manhattan Project]], which ultimately led to the successful development of the first [[atomic bomb]] in America.<ref>{{Cite news|url=https://www.theguardian.com/technology/2009/nov/01/qian-xuesen-obituary|title=Qian Xuesen obituary|last1=Brown|first1=Kerry|date=2009-11-01|work=The Guardian|access-date=2019-11-21|language=en-GB|issn=0261-3077}}</ref><ref name="The Two Lives of Qian Xuesen">{{Cite news|url=https://www.newyorker.com/news/evan-osnos/the-two-lives-of-qian-xuesen|title=The Two Lives of Qian Xuesen|last1=Osnos|first1=Evan|journal=The New Yorker|date=2009-11-03|access-date=2019-11-21|language=en|issn=0028-792X}}</ref> Later on, he would eventually return to China, where he would make important contributions to [[China]]'s [[missile]] and [[Chinese space program|space program]].<br />
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Qian Xuesen, or Hsue-Shen Tsien (; 11 December 1911 – 31 October 2009), was a Chinese mathematician, cyberneticist, aerospace engineer, and physicist who made significant contributions to the field of aerodynamics and established engineering cybernetics. Recruited from MIT, he joined Theodore von Kármán's group at Caltech. During WWII, he was involved in the Manhattan Project, which ultimately led to the successful development of the first atomic bomb in America. Later on, he would eventually return to China, where he would make important contributions to China's missile and space program.<br />
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钱学森,即Hsue-Shen Tsien(1911年12月11日至2009年10月31日) ,是中国数学家、控制论家、航空航天工程师和物理学家,在空气动力学领域做出了重大贡献,建立了工程控制论。从麻省理工学院毕业后,他加入了Theodore von Kármán西奥多·冯·卡门在加州理工学院的团队。在第二次世界大战期间,他参与了曼哈顿计划,帮助美国成功研制出第一颗原子弹。后来,他终于回到了中国,在那里他为中国的导弹和太空计划做出了重要贡献。<br />
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During the [[Second Red Scare]], in the 1950s, the [[US federal government]] accused him of [[communist]] sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance.<ref name="autogenerated57">{{cite journal |date = {{Date|2008-01-07|dmy}} |title = Person of the Year: Qian Xuesen |url = http://aviationweek.com/awin/qian-xuesen-laid-foundation-china-s-space-rise |journal = Aviation Week and Space Technology |volume = 168 |pages = 57–61 |last1 = Perrett |first1 = Bradley |last2 = Asker |first2 = James R. |number = 1 |access-date = {{Date|2015-02-02|dmy}} }} {{subreq}}</ref> He decided to return to China, but he was detained at [[Terminal Island]], near [[Los Angeles]].<ref>{{cite web |url = http://www.astronautix.com/astros/tsien.htm |author = <!--Staff writer(s); no by-line.--> |title = Tsien |website = Encyclopedia Astronautica |access-date = {{Date|2015-02-02|dmy}} |url-status = dead |archive-url = https://web.archive.org/web/20131013215748/http://www.astronautix.com/astros/tsien.htm |archive-date = 2013-10-13 }}</ref><br />
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During the Second Red Scare, in the 1950s, the US federal government accused him of communist sympathies. In 1950, despite protests by his colleagues, he was stripped of his security clearance. He decided to return to China, but he was detained at Terminal Island, near Los Angeles.<br />
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在20世纪50年代的第二次红色恐慌中,美国联邦政府指责他同情共产主义。1950年,尽管同事们一致抗议,他还是被剥夺了安全许可。他决定返回中国,但他被拘留在洛杉矶附近的终端岛。<br />
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After spending five years under [[house arrest]],<ref name="caltech1">{{cite web |url = http://today.caltech.edu/today/story-display.tcl?story_id=39604 |title = Tsien Hsue-Shen Dies |website = Caltech |author=<!--Staff writer(s); no by-line.--> |date = {{Date|2009-11-02|dmy}} |accessdate = {{Date|2015-02-02|dmy}} |archive-url = https://web.archive.org/web/20100612190920/http://today.caltech.edu/today/story-display.tcl?story_id=39604 |archive-date = {{date|2010-06-12|dmy}} |url-status = dead }}</ref> he was released in 1955 in exchange for the [[repatriation]] of American pilots who had been captured during the [[Korean War]]. He left the United States in September 1955 on the [[American President Lines]] passenger liner [[SS President Cleveland (1947)|SS ''President Cleveland'']], arriving in China via [[Hong Kong]].<ref name="MJ550913">{{cite news |url = https://news.google.com/newspapers?id=LAkkAAAAIBAJ&pg=7147%2C5707600 |title = US Deporting Rocket Expert |author=<!--Staff writer(s); no by-line.--> |date = {{Date|1955-09-13|dmy}} |newspaper=The Milwaukee Journal |access-date = {{Date|2015-02-02|dmy}} }}</ref><br />
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After spending five years under house arrest, he was released in 1955 in exchange for the repatriation of American pilots who had been captured during the Korean War. He left the United States in September 1955 on the American President Lines passenger liner SS President Cleveland, arriving in China via Hong Kong.<br />
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在软禁了五年之后,他于1955年被释放,作为交换,在朝鲜战争中被俘的美国飞行员也被遣返回美国。1955年9月,他离开美国,前往美国总统班轮克利夫兰航空公司的SS总统,经由香港抵达中国。 <br />
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Upon his return, he helped lead the [[China and weapons of mass destruction|Chinese nuclear weapons program]].<ref>{{cite web |url = https://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory|website = LA Times |date = {{Date|2016-09-16|dmy}} |access-date = {{Date|2019-11-26|dmy}} }}</ref> This effort ultimately led to China's first successful [[596 (nuclear test)|atomic bomb test]] and [[Test No. 6|hydrogen bomb test]], making China the fifth nuclear weapons state, and achieving the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history. Additionally, Qian's work led to the development of the [[Dongfeng (missile)|Dongfeng ballistic missile]] and the [[Chinese space program]]. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry".<ref>{{cite web |url = http://scitech.people.com.cn/GB/10294899.html |title = 钱学森:历尽险阻报效祖国 火箭之王淡泊名誉 |trans-title = Qian Xuesen: King of Rocketry who experienced obstacles in serving the Motherland |website = 人民网 (People.com.cn) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-10-31|dmy}} |language = zh-Hans-CN }}</ref><ref>{{cite web |url = http://news.163.com/09/1031/17/5MVIKNT90001124J.html |title = 美国航空周刊2008年度人物:钱学森 |trans-title = US Aviation Week & Space Technology Person of the Year 2008: Qian Xuesen |website = 网易探索(广州) |date = {{Date|2009-10-31|dmy}} |access-date = {{Date|2009-11-11|dmy}} |language = zh-Hans-CN }}</ref> He is recognized as one of the founding fathers of [[Two Bombs, One Satellite]].<ref>{{cite news |title = 23位两弹一星元勋已有17人离世 媒体解析其功绩 |url = http://news.china.com/domesticgd/10000159/20160529/22762769.html |website = China.com |date = 30 May 2016 |language = zh-Hans-CN}}</ref><br />
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Upon his return, he helped lead the Chinese nuclear weapons program. This effort ultimately led to China's first successful atomic bomb test and hydrogen bomb test, making China the fifth nuclear weapons state, and achieving the fastest fission-to-fusion development in history. Additionally, Qian's work led to the development of the Dongfeng ballistic missile and the Chinese space program. For his contributions, he became known as the "Father of Chinese Rocketry", nicknamed the "King of Rocketry". He is recognized as one of the founding fathers of Two Bombs, One Satellite.<br />
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回国后,他帮助领导了中国的核武器计划。这一努力最终导致了中国第一次成功的原子弹试验和氢弹试验,使中国成为第五个拥有核武器的国家,并实现了历史上最快的裂变-聚变发展。此外,钱的工作导致了东风弹道导弹和中国太空计划的发展。由于他的贡献,他被称为“中国火箭之父” ,绰号“火箭之王”。他被公认为“两炸一卫”的创始人之一。<br />
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In 1957, Qian was elected an [[academician]] of the [[Chinese Academy of Sciences]]. He served as a [[Vice Chairperson of the Chinese People's Political Consultative Conference|Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference]] from 1987 to 1998.<br />
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In 1957, Qian was elected an academician of the Chinese Academy of Sciences. He served as a Vice Chairman of the National Committee of the Chinese People's Political Consultative Conference from 1987 to 1998.<br />
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1957年钱当选中国科学院院士。1987年至1998年任中国人民政治协商会议全国委员会副主席。<br />
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He was the cousin of [[mechanical engineer]] [[Hsue-Chu Tsien]], who was involved in the aerospace industries of China and the United States; his nephew is [[Roger Y. Tsien]], the 2008 winner of the [[Nobel Prize in Chemistry]].<br />
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He was the cousin of mechanical engineer Hsue-Chu Tsien, who was involved in the aerospace industries of China and the United States; his nephew is Roger Y. Tsien, the 2008 winner of the Nobel Prize in Chemistry.<br />
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他的侄子是2008年诺贝尔化学奖得主钱学森。<br />
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== Early life and education ==<br />
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Qian was born in [[Shanghai]], with ancestral roots in [[Hangzhou]]. He graduated from [[The High School Affiliated to Beijing Normal University]], with [[Lu Shijia]] as classmate, and attended National Chiao Tung University (now [[Shanghai Jiaotong University]]) in 1934. There, he received a degree in [[mechanical engineering]] with an emphasis on railroad administration. He interned at [[Nanchang Laoyingfang Airport|Nanchang Air Force Base]].<br />
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Qian was born in Shanghai, with ancestral roots in Hangzhou. He graduated from The High School Affiliated to Beijing Normal University, with Lu Shijia as classmate, and attended National Chiao Tung University (now Shanghai Jiaotong University) in 1934. There, he received a degree in mechanical engineering with an emphasis on railroad administration. He interned at Nanchang Air Force Base.<br />
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钱生于上海,祖籍杭州。他毕业于北京师范大学附属中学,和陆世佳同学,并于1934年就读于国立交通大学交通大学。在那里,他获得了机械工程学位,重点是铁路管理。他在 Nanchang Air Force Base 实习。<br />
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In August 1935, Qian left China on a [[Boxer Indemnity Scholarship]] to study mechanical engineering at the [[Massachusetts Institute of Technology]] (MIT), where he earned a [[Master of Science]] degree after one year.<br />
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In August 1935, Qian left China on a Boxer Indemnity Scholarship to study mechanical engineering at the Massachusetts Institute of Technology (MIT), where he earned a Master of Science degree after one year.<br />
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1935年8月,钱获得庚款奖学金离开中国,前往麻省理工学院(MIT)学习机械工程,一年后获得理学硕士学位。<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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While at MIT he was called Hsue-Shen Tsien. He was influenced by the methods of American engineering education, especially its focus on experimentation. This was in contrast to the contemporary approach practiced by many Chinese scientists, which emphasized theoretical elements rather than "hands-on" experience. Tsien's experiments included plotting of pitot pressures using mercury-filled manometers.<br />
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在麻省理工学院的时候,他的名字叫许淑慎。他受到美国工程教育方法的影响,尤其是美国工程教育对实验的重视。这与许多中国科学家采用的当代方法形成了鲜明对比,当代方法强调理论要素,而不是“实践”经验。钱永健的实验包括使用充满水银的压力计绘制皮托管压力。<br />
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[[Theodore von Kármán]], Tsien's doctoral advisor, described their first meeting:<br />
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Theodore von Kármán, Tsien's doctoral advisor, described their first meeting:<br />
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钱永健的西奥多·冯·卡门,钱永健的博士生导师,描述了他们的第一次会面:<br />
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{{quote|One day in 1936 he came to me for advice on further graduate studies. This was our first meeting. I looked up to observe a slight short young man, with a serious look, who answered my questions with unusual precision. I was immediately impressed with the keenness and quickness of his mind, and I suggested that he enroll at Caltech for advanced study ... Tsien agreed. He worked with me on many mathematical problems. I found him to be quite imaginative, with a mathematical aptitude that he combined successfully with a great ability to visualize accurately the physical picture of natural phenomena. Even as a young student he helped clear up some of my own ideas on several difficult topics. These are gifts which I had not often encountered and Tsien and I became close colleagues.<ref name=TvK>Theodore von Kármán with Lee Edson (1967) ''The Wind and Beyond'', chapter 38: Dr. Tsien of Red China, pp.&nbsp;308–15.</ref>{{rp|309}}}}<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and [[Josephine de Karman|my sister]] took to him because of his interesting ideas and straightforward manner."<br />
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Kármán made his home a social scene for the aerodynamicists of Pasadena, and Tsien was drawn in: "Tsien enjoyed visiting my home, and my sister took to him because of his interesting ideas and straightforward manner."<br />
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对于帕萨迪纳的空气动力学家来说,卡门把自己的家变成了一个社交场所,钱被吸引了进来: “钱喜欢来我家,我姐姐喜欢他,因为他有趣的想法和直截了当的态度。”<br />
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== Career in the United States ==<br />
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[[File:Left-right Ludwig Prandtl, Theodore Von Karman, Tsien Hsue-sen.jpg|thumb|250px|Left to right: [[Ludwig Prandtl]] (German scientist), Hsue-Shen Tsien, [[Theodore von Kármán]]. Prandtl served Germany during [[World War II]]; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary [[United States Army|U.S. Army]] rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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Left to right: [[Ludwig Prandtl (German scientist), Hsue-Shen Tsien, Theodore von Kármán. Prandtl served Germany during World War II; von Kármán and Tsien served the United States; after 1956, Tsien served China. Tsien's overseas cap displays his temporary U.S. Army rank of colonel. Prandtl was von Kármán's doctoral adviser; von Kármán in turn was Tsien's.]]<br />
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从左到右: [路德维希普兰特尔(德国科学家) ,钱学森,西奥多·冯·卡门。普朗特在第二次世界大战期间为德国服务; 冯 · 卡尔曼和钱为美国服务; 1956年后,钱为中国服务。钱存训的海外军帽展示了他暂时的美国陆军上校军衔。普朗特是冯 · 卡门的博士生导师,而冯 · 卡门则是西恩的博士生导师<br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of [[Frank Malina]], other students of von Kármán, and their associates, including [[John Whiteside Parsons|Jack Parsons]]. Along with his fellow students, he was involved in rocket-related experiments at the [[Guggenheim Aeronautical Laboratory]] at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad."<ref name="caltech2" /><ref>{{cite book |url = https://archive.org/details/threadofsilkworm00chan/page/109 |last1 = Chang |first1 = Iris |authorlink = Iris Chang |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |pages = [https://archive.org/details/threadofsilkworm00chan/page/109 109–117] |location = New York |isbn = 978-0-465-08716-7 }}</ref> Tsien received his PhD from Caltech in 1939.<ref name="thesis-tsien-1939">{{cite thesis |url = http://resolver.caltech.edu/CaltechETD:etd-01122004-105646 |title = Problems in motion of compressible fluids and reaction propulsion |year = 1939 |institution = [[California Institute of Technology]] |degree = Ph.D. |last1 = Tsien |first1 = Hsue-shen }}</ref><br />
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Shortly after arriving at Caltech in 1936, Tsien became fascinated with the rocketry ideas of Frank Malina, other students of von Kármán, and their associates, including Jack Parsons. Along with his fellow students, he was involved in rocket-related experiments at the Guggenheim Aeronautical Laboratory at Caltech. Around the university, the dangerous and explosive nature of their work earned them the nickname "Suicide Squad." Tsien received his PhD from Caltech in 1939.<br />
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1936年到达加州理工学院后不久,钱就着迷于弗兰克 · 马里纳、冯 · 卡曼的其他学生以及他们的同事,包括杰克 · 帕森斯的火箭思想。和他的同学们一起,他在加州理工学院的古根海姆航空试验室参与了火箭相关的实验。在大学里,他们工作的危险性和爆炸性为他们赢得了“自杀小队”的绰号钱存训于1939年获得加州理工学院的博士学位。<br />
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During the [[Second World War]], Tsien worked in the [[Manhattan Project]], which led to America successfully developing the first [[atomic bomb]].<ref name="The Two Lives of Qian Xuesen"/><ref>{{Cite web|url=https://www.pri.org/stories/2017-02-06/us-trained-scientist-was-deported-then-became-father-chinese-rocketry|title=A US-trained scientist was deported, then became the 'father of Chinese rocketry'|website=Public Radio International|language=en|access-date=2019-11-21}}</ref><ref>{{Cite web|url=https://radiichina.com/its-not-rocket-science-except-when-it-is-the-strange-case-of-qian-xuesen/|title=It's Not Rocket Science, Except When it is: The Strange Case of Qian Xuesen|date=2018-08-15|website=RADII {{!}} Culture, Innovation, and Life in today's China|language=en-US|access-date=2019-11-21}}</ref> In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name [[Jet Propulsion Laboratory]] (JPL), originally a proposal to the Army for developing missiles in response to Germany's [[V-2 rocket]]. This led to [[Private (missile)|Private A]], which flew in 1944, and later the [[MGM-5 Corporal|Corporal]], the [[WAC Corporal]], and other designs.<br />
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During the Second World War, Tsien worked in the Manhattan Project, which led to America successfully developing the first atomic bomb. In 1943, Tsien and two other members of their rocketry group drafted the first document to use the name Jet Propulsion Laboratory (JPL), originally a proposal to the Army for developing missiles in response to Germany's V-2 rocket. This led to Private A, which flew in 1944, and later the Corporal, the WAC Corporal, and other designs.<br />
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第二次世界大战期间,钱存训参与曼哈顿计划,使美国成功研制出第一颗原子弹。1943年,钱永健和他们火箭研究小组的另外两名成员起草了第一份文件,使用了喷气推进实验室的名字,最初是为了应对德国的 V-2火箭而向陆军提出的开发导弹的建议。这导致了1944年飞行的二等兵 a,以及后来的下士、 WAC 下士和其他设计。<br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including [[Wernher von Braun]].<ref>{{Cite news|url=https://www.nytimes.com/2009/11/04/world/asia/04qian.html|title=Qian Xuesen, Father of China's Space Program, Dies at 98|last1=WINES|first1=MICHAEL|date=2009-11-04|work=[[New York Times]]|access-date=2019-11-24|language=en}}</ref><ref>{{Cite news|url=https://www.wsj.com/articles/SB125721495250424443|title=Trained in the U.S., Scientist Became China's 'Rocket King'|date=2009-11-04|work=[[Wall Street Journal]]|access-date=2019-11-24|language=en}}</ref><br />
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In 1945, as an Army colonel with a security clearance, Tsien was sent to Germany to investigate laboratories and question German scientists, including Wernher von Braun.<br />
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1945年,钱存训作为一名拥有安全许可的陆军上校,被派往德国调查实验室,质询包括沃纳·冯·布劳恩在内的德国科学家。<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion."<ref name="2008poy">{{cite journal |url = http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/aw010708p1.xml |title = Qian Xuesen Laid Foundation For Space Rise in China |last1 = Perrett |first1 = Bradley |date = {{Date|2008-01-06|dmy}} |journal = Aviation Week and Space Technology |volume = 168 |number = 1 |archive-url = https://web.archive.org/web/20110521055346/http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news%2Faw010708p1.xml |archive-date = 2011-05-21 |url-status = dead |access-date = {{Date|2015-02-02|dmy}} }}</ref> During this time, he worked on designing an intercontinental space plane, which would later inspire the [[X-20 Dyna-Soar]], a precursor to the American [[Space Shuttle]].<br />
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Von Kármán wrote of Tsien, "At the age of 36, he was an undisputed genius whose work was providing an enormous impetus to advances in high-speed aerodynamics and jet propulsion." During this time, he worked on designing an intercontinental space plane, which would later inspire the X-20 Dyna-Soar, a precursor to the American Space Shuttle.<br />
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冯 · 卡曼在提到钱存训时写道: “在他36岁的时候,他是一个无可争议的天才,他的工作为高速空气动力学和喷气推进技术的发展提供了巨大的推动力。”在此期间,他致力于设计一种洲际航天飞机,这种飞机后来激发了美国航天飞机的前身 X-20动力-翱翔。<br />
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Tsien married [[Jiang Ying (musician)|Jiang Ying]] (蒋英), a famed opera singer and the daughter of [[Jiang Baili]] (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to [[Kuomintang]] leader [[Chiang Kai-shek]]. The Tsiens were married on 14 September 1947<ref>Chang (1995), p.&nbsp;139.</ref> in [[Shanghai]], and had two children; their son [[Qian Yonggang]] (钱永刚, also known as Yucon Tsien<ref>{{cite web |url = https://dl.library.ucla.edu/islandora/object/edu.ucla.library.specialCollections.latimes:4566 |title = California Institute of Technology scientist, Dr. Hsue-shen Tsien with his family onboard SS President Cleveland, 1955 |publisher = Los Angeles Times Photographic Archive |access-date = 2019-03-24 }}</ref>) was born in [[Boston]] on 13 October 1948,<ref>Chang (1995), p.&nbsp;141.</ref> while their daughter [[Qian Yongzhen]] (钱永真) was born in early 1950<ref>Chang (1995), p.&nbsp;153.</ref> when the family was residing in [[Pasadena, California|Pasadena]], California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato. The elder Jiang was a military strategist and adviser to Kuomintang leader Chiang Kai-shek. The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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Tsien married Jiang Ying (蒋英), a famed opera singer and the daughter of Jiang Baili (蒋百里) and his wife, Japanese nurse Satô Yato.老蒋是国民党领袖蒋的军事战略家和顾问。The Tsiens were married on 14 September 1947 in Shanghai, and had two children; their son Qian Yonggang (钱永刚, also known as Yucon Tsien) was born in Boston on 13 October 1948, while their daughter Qian Yongzhen (钱永真) was born in early 1950 when the family was residing in Pasadena, California.<br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947.<ref>Chang (1995), pp.&nbsp;139–140.</ref> In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<ref name="caltech2">{{cite web |url = https://www.caltech.edu/about/history |title = GALCIT History }}{{dead link |date=December 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><br />
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Shortly after his wedding, Tsien returned to America to take up a teaching position at MIT. Jiang Ying would join him in December 1947. In 1949, with the recommendation of von Kármán, Tsien became Robert H. Goddard Professor of Jet Propulsion at Caltech.<br />
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婚礼后不久,钱存训回到美国,在麻省理工任教。1947年12月,蒋英加入了他的行列。1949年,在冯 · 卡门的推荐下,西恩成为加州理工学院喷气推进罗伯特·戈达德的教授。<br />
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In 1947, Tsien was granted a permanent resident permit,<ref name="MJ550913" /> and in 1949, he applied for naturalization, although he could not obtain citizenship.<ref name="autogenerated57" /> Except for the memories of a few individuals,<ref name="autogenerated57" /> there is no other official proof indicating that Tsien had tried to apply for naturalization. Years later, his wife Jiang Ying said in an interview with [[Phoenix Television]] that Tsien did not apply for naturalization.<ref>{{cite web |url = http://v.ifeng.com/history/renwujingdian//201202/18b53c55-2072-4e66-90d8-5cea9450fd38.shtml |script-title = zh:2012-02-18我的中国心 天籁美音——蒋英 |trans-title = My Chinese Heart heavenly tone: Jiang Ying |date = {{Date|2012-02-18|dmy}} |author = 凤凰卫视 |publisher = 凤凰网/凤凰视频 |access-date = {{Date|2015-02-02|dmy}} |language = zh }}</ref><br />
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In 1947, Tsien was granted a permanent resident permit,<br />
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1947年钱存训获得永久居留许可,<br />
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=== Detention ===<br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended.<ref>Chang (1995), p.&nbsp;158.</ref> However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by [[Mao Zedong]].<ref name="caltech1" /><ref>Chang (1995), pp.&nbsp;149–150.</ref><br />
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By the early 1940s, US Army Intelligence was already aware of allegations that Tsien was a Communist, but his security clearance was not suspended. However, on 6 June 1950, his security clearance was revoked and Tsien was questioned by the FBI. Two weeks later Tsien announced that he would be resigning from Caltech and returning to China, which by then was effectively governed by the Communist Party of China led by Mao Zedong.<br />
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到20世纪40年代早期,美国陆军情报局已经知道钱存训是共产主义者的指控,但是他的安全许可并没有被停职。然而,1950年6月6日,他的安全许可被撤销,钱存训受到联邦调查局的审问。两周后,钱存训宣布他将辞去加州理工学院的工作,回到中国,那时中国实际上是由毛泽东领导的中国共产党统治的。<br />
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In August, Tsien had a conversation on the subject with the then [[Under Secretary of the Navy]] [[Dan A. Kimball]], whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<ref>{{harvnb|Ryan|Summerlin|1968|p=215}}</ref><br />
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In August, Tsien had a conversation on the subject with the then Under Secretary of the Navy Dan A. Kimball, whom Tsien knew on a personal basis. After Tsien told him of the allegations, Kimball responded, "Hell, I don't think you're a Communist", at which point Tsien indicated that he still intended to leave the country, saying "I'm Chinese. I don't want to build weapons to kill my countrymen. It's that simple." Kimball then said, "I won't let you out of the country."<br />
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8月,钱存训与当时的海军副部长丹 · a · 金博尔(Dan a. Kimball)就这个问题进行了交谈,钱存训私下认识金博尔。钱存训告诉他这些指控后,金博尔回应说,“见鬼,我不认为你是共产主义者”。钱存训暗示,他仍然打算离开中国,并说“我是中国人。”。我不想制造杀死我同胞的武器。就是这么简单。”金博尔接着说,“我不会让你出国的。”<br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes."<ref>Chang (1995), p.&nbsp;157.</ref> Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as [[Klaus Fuchs]].<ref>Chang (1995), p.&nbsp;160.</ref> Subsequent examination of the documents showed they contained no classified material.<ref name="MJ550913" /><br />
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After the firm in charge of arranging Tsien's move back to China tipped off U.S. Customs that some of the papers encountered among his possessions were marked "Secret" or "Confidential," U.S. officials seized them from a Pasadena warehouse. The U.S. Immigration and Naturalization Service issued a warrant for Tsien's arrest on 25 August. Tsien claimed that the security-stamped documents were mostly written by himself and had outdated classifications, adding that, "There were some drawings and logarithm tables, etc., which someone might have mistaken for codes." Included in the material was a scrapbook with news clippings about the trials of those charged with atomic espionage, such as Klaus Fuchs. Subsequent examination of the documents showed they contained no classified material. Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him. Weinbaum was convicted of perjury and sentenced to four years. Tsien was taken into custody on 6 September 1950 for questioning<br />
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在负责安排钱存训返回中国的公司向美国海关透露,钱存训的一些文件被标记为“秘密”或“机密”之后,美国官员从帕萨迪纳市的一个仓库中没收了这些文件。8月25日,美国美国移民及归化局发出了对钱存训的逮捕令。钱存训声称,这些加了安全标签的文件大部分是他自己写的,分类已经过时,并补充说,“里面有一些绘图和对数表等,有人可能把它们误认为代码。”这些材料包括一本剪贴簿,里面有关于那些被指控从事原子间谍活动的人受审的剪报,比如克劳斯 · 福克斯。随后对这些文件的检查表明,其中没有任何机密材料。对 Weinbaum 的审判于8月30日开始,Frank Oppenheimer 和 Parsons 都作了不利于他的证词。温鲍姆因伪证罪被判刑四年。钱存训于1950年9月6日被拘留审问<br />
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While at Caltech, Tsien had secretly attended meetings with J. Robert Oppenheimer's brother [[Frank Oppenheimer]], [[John Whiteside Parsons|Jack Parsons]], and [[Frank Malina]] that were organized by the Russian-born Jewish chemist Sidney Weinbaum and called Professional Unit 122 of the Pasadena Communist Party.<ref>[[Ray Monk]], ''Robert Oppenheimer: A Life Inside the Center'' [[Random House]] {{ISBN|978-0-385-50407-2}} (2012)</ref> Weinbaum's trial commenced on 30 August and both Frank Oppenheimer and Parsons testified against him.<ref>[[George Pendle]], ''Strange Angel: The Otherworldly Life of Rocket Scientist John Whiteside Parsons'' [[Mariner Books]] (2006) {{ISBN|0-297-84853-4}} p.&nbsp;291.</ref> Weinbaum was convicted of perjury and sentenced to four years.<ref>Chang (1995), p.&nbsp;159.</ref> Tsien was taken into custody on 6 September 1950 for questioning<ref name="MJ550913" /> and for two weeks detained at [[Federal Correctional Institution, Terminal Island|Terminal Island]], a low-security United States federal prison near the ports of Los Angeles and [[Long Beach, California|Long Beach]].<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving Los Angeles County without permission, effectively placing him under house arrest.<br />
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1951年4月26日,钱存训被宣布被驱逐出境,未经许可不得离开洛杉矶县,实际上将他软禁在家。<br />
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When Tsien had returned from China with his new bride in 1947, he had answered "no" on an immigration questionnaire that asked if he ever had been a member of an organization advocating overthrow of the U.S. Government by force. This, together with an American [[CPUSA|Communist Party]] document from 1938 with Tsien's name on it, was used to argue that Tsien was a national security threat. Prosecutors also cited a cross-examination session where Tsien said, "I owe allegiance to the people of China" and would "certainly not" let the United States government make his decision for him as to whom he would owe allegiance to in the event of a conflict between the U.S. and communist China.<ref>{{harvnb|Ryan|Summerlin|1968|pp=113, 115}}</ref><br />
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During this time, Tsien wrote Engineering Cybernetics, which was published by McGraw Hill in 1954. The book deals with the practice of stabilizing servomechanisms. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by perturbation theory, and von Neumann's theory of error control (chapter 18). Ezra Krendel reviewed the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex control systems." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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在此期间,钱学森撰写了《工程控制论》 ,并于1954年由麦格劳 · 希尔出版社出版。这本书论述了稳定伺服机构的实践。在它的18章中,它考虑了多变量系统的非相互作用控制,摄动理论的控制设计,和 von Neumann 的错误控制理论(第18章)。埃兹拉 · 克伦德尔评论了这本书,指出“对于那些对复杂控制系统的整体理论感兴趣的人来说,很难夸大钱永健这本书的价值。”显然,钱的方法主要是实用的,正如克伦德尔指出,对于伺服机构,“通常的线性稳定性设计标准是不充分的,其他标准产生的物理问题必须使用。”<br />
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On 26 April 1951, Tsien was declared subject to deportation and forbidden from leaving [[Los Angeles County, California|Los Angeles County]] without permission, effectively placing him under [[house arrest]].<ref>{{harvnb|Ryan|Summerlin|1968|p=141}}</ref><br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties. Qian arrived at Hong Kong on 8 October 1955 and entered China via the Kowloon–Canton Railway later that day.<br />
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钱成为中美之间长达五年的秘密外交和谈判的对象。在这段时间里,他一直生活在监视之下,被允许在没有任何分类研究任务的情况下教书。钱于一九五五年十月八日抵达香港,并于当日稍后经九广铁路进入中国。<br />
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During this time, Tsien wrote ''Engineering Cybernetics'', which was published by [[McGraw Hill]] in 1954. The book deals with the practice of stabilizing [[servomechanism]]s. In its 18 chapters, it considers non-interacting controls of many-variable systems, control design by [[perturbation theory]], and [[John von Neumann|von Neumann]]'s theory of [[error control]] (chapter 18). Ezra Krendel reviewed<ref>Ezra Krendel (1955) "Review of Engineering Cybernetics", [[Journal of the Franklin Institute]] 259(4): 367</ref> the book, stating that it is "difficult to overstate the value of Tsien's book to those interested in the overall theory of complex [[control system]]s." Evidently, Tsien's approach is primarily practical, as Krendel notes that for servomechanisms, the "usual linear design criterion of stability is inadequate and other criteria arising from the physics of the problem must be used."<br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<br />
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几年来一直试图让钱留在美国的金博尔副国务卿评论了他的待遇: “这是这个国家做过的最愚蠢的事情。他和我一样不是共产主义者,我们强迫他离开。”<br />
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== Return to China ==<br />
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Qian became the subject of five years of secret diplomacy and negotiation between the U.S. and China. During this time, he lived under constant surveillance with the permission to teach without any classified research duties.<ref name="caltech1" /> Qian received support from his colleagues at Caltech during his incarceration, including president [[Lee DuBridge]], who flew to Washington to argue Qian's case. Caltech appointed attorney [[Grant Cooper (attorney)|Grant Cooper]] to defend Qian.<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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他于一九五八年参与中国科技大学的成立,并担任大学现代力学系系主任多年。<br />
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The travel ban on Qian was lifted on {{date|1955-08-04|dmy}},<ref name="MJ550913" /> and he resigned from Caltech shortly thereafter. With President [[Dwight Eisenhower]] personally agreeing, Qian departed from Los Angeles for Hong Kong aboard the ''[[SS President Cleveland (1947)|SS President Cleveland]]'' in September 1955 amidst rumors that his release was a swap for 11 U.S. airmen held captive by China since the end of the Korean War.<ref>Brownell, Richard. Space exploration. Detroit, Lucent Books, 2012. 82 p.</ref><ref>{{Cite web | url=http://www.astronautix.com/t/tsien.html | title=Tsien}}</ref><ref>{{cite news |url=https://news.google.com/newspapers?id=CooeAAAAIBAJ&pg=3115%2C1559834 |title=Scientist To Be Deported By U.S. |author=<!--Staff writer(s); no by-line.--> |date={{date|1955-09-13|dmy}} |newspaper=DAytona Beach Morning Journal |agency = AP |access-date = {{date|2015-02-02|dmy}} }}</ref> Qian arrived at Hong Kong on 8 October 1955 and entered China via the [[Kowloon–Canton Railway]] later that day.<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of systematics, and made contributions to science and technology systems, somatic science, engineering science, military science, social science, the natural sciences, geography, philosophy, literature and art, and education. His advancements in the concepts, theories, and methods of the system science field include studying the open complex giant system. Additionally, he helped establish the Chinese school of complexity science.<br />
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除了火箭技术,钱在许多领域的研究存在。他是系统科学的创始人之一,在科学技术体系、躯体科学、工程科学、军事科学、社会科学、自然科学、地理学、哲学、文学艺术和教育等方面做出了贡献。他在系统科学领域的概念、理论和方法方面的进展包括研究开放的复杂巨系统。此外,他还帮助建立了中国复杂性科学学派。<br />
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Under Secretary Kimball, who had tried for several years to keep Qian in the U.S., commented on his treatment: "It was the stupidest thing this country ever did. He was no more a Communist than I was, and we forced him to go."<ref name="autogenerated57" /><br />
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From the 1980s onward, Qian had advocated the scientific investigation of traditional Chinese medicine, Qigong, and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<br />
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自20世纪80年代以来,钱一直倡导对中医气功的科学研究,倡导“人体特殊功能”的概念。他特别鼓励科学家们积累气功的观测数据,以便建立未来的科学理论。<br />
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Upon his return, Qian began a remarkably successful career in rocket science, boosted by the reputation he garnered for his past achievements as well as Chinese state support for his nuclear research. He led and eventually became the father of the Chinese missile program, which constructed the [[Dongfeng (missile)|Dongfeng ballistic missiles]] and the [[Long March (rocket family)|Long March space rockets]].<br />
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Qian Xuesen Library, Xi'an Jiaotong University<br />
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西安交通大学钱学森图书馆<br />
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== Chinese nuclear program and other studies ==<br />
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In October 1956, he became the director of the [[China Aerospace Science and Technology Corporation|Fifth Academy]] of the [[Ministry of National Defense of the People's Republic of China|Ministry of National Defense]], tasked with ballistic missile and nuclear weapons development. He was part of the overall effort that resulted in the successful "596" atomic bomb test on 16 October 1964, and the "Test No. 6" hydrogen bomb test on 17 June 1967. This was the fastest [[Nuclear fission|fission]]-to-[[Nuclear fusion|fusion]] development in history at 32 months, compared to 86 months for the United States and 75 months for the USSR, and gave China a [[thermonuclear device]] ahead of major Western powers like [[France]].<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<br />
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钱于1991年退休,平静地生活在北京,拒绝与西方人交谈。<br />
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Qian's reputation as a prominent scientist who was caught up in the red scare in the United States gave him considerable influence in the era of [[Mao Zedong]] and afterward. Qian eventually rose through Party ranks to become a [[Central Committee of the Communist Party of China|Central Committee]] member. He became associated with the ''China's Space Program - From Conception to Manned Spaceflight'' initiative.<br />
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In 1979, Qian was awarded Caltech's Distinguished Alumni Award for his achievements. Qian eventually received his award from Caltech, and with the help of his friend Frank Marble brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
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1979年,钱获得加州理工学院杰出校友奖。钱最终从加州理工学院获得了这个奖项,在朋友弗兰克 · 马布尔的帮助下,钱在一个被广泛报道的仪式上把它带回了家。此外,在20世纪90年代早期,加州理工学院向他提供了装有钱研究成果的文件柜。<br />
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Qian was elected as an [[academician]] of the [[Chinese Academy of Sciences]] in 1957, a lifelong honor granted to Chinese scientists who have made significant advancements in their field. He organized scientific seminars and dedicated some of his time to training successors for his positions.<ref>[http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm 科技网 -《科技日报》- 钱学森的系统科学成就和贡献] {{webarchive |url = https://web.archive.org/web/20120514150132/http://www.stdaily.com/kjrb/content/2010-10/24/content_239983.htm |date = 2012-05-14 }}</ref><br />
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Qian was invited to visit the US by the American Institute of Aeronautics and Astronautics after the normalization of the Sino-US relationship, but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<br />
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在中美关系正常化之后,美国航天航空学会邀请钱访问美国,但他拒绝了邀请,并要求对拘留他一事进行正式道歉。在2002年发表的一份回忆录中,马柏表示,他认为钱“对美国政府失去了信心” ,但他“一直对美国人民怀有非常温暖的感情”<br />
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He was heavily involved in the establishment of the University of Science and Technology of China (USTC) in 1958 and served as the Chairman of the Department of Modern Mechanics of the university for a number of years.<br />
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The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the Long March rocket, which successfully launched the Shenzhou V mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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中国政府在1992年启动了载人航天计划,据报道,由于中国在太空的长期历史,得到了俄罗斯的一些帮助。钱的研究被用作长征火箭的基础,长征火箭于2003年10月成功发射了神舟五号任务。钱老在病床上通过电视观看了中国第一次载人航天飞行。<br />
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Outside of rocketry, Qian had a presence in numerous areas of study. He was among the creators of [[systematics]], and made contributions to science and technology systems, [[somatic science]], [[engineering science]], [[military science]], [[social science]], the [[natural sciences]], geography, [[philosophy]], literature and art, and education. His advancements in the concepts, theories, and methods of the [[system science]] field include studying the [[open complex giant system]].<ref>钱学森:《创建系统学(新世纪版)》,上海交通大学出版社</ref><ref>钱学森:《论系统工程(新世纪版)》,上海交通大学出版社</ref> Additionally, he helped establish the Chinese school of [[complexity science]].<br />
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In 2008, he was named Aviation Week and Space Technology Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year. Furthermore, that year China Central Television named Qian as one of the eleven most inspiring people in China.<br />
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2008年,他被评为航空周刊和航天技术年度人物。这种认可并不是一种荣誉,而是给予那些在过去一年中被认为对航空业影响最大的人。此外,那一年,中国中央电视台将钱列为中国十一个最鼓舞人心的人物之一。<br />
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From the 1980s onward, Qian had advocated the scientific investigation of [[traditional Chinese medicine]], [[Qigong]], and the concept of "special human body functions". He particularly encouraged scientists to accumulate observational data on qigong so that future scientific theories could be established.<ref>{{cite book |author = Qian Xuesen |title = 《创建人体科学》 |location = Chengdu |publisher = Sichuan Education Publishing House |date = May 1989 |edition = 1st |display-authors = etal }}</ref><br />
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In July 2009, the Omega Alpha Association, an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<br />
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2009年7月,欧米茄阿尔法协会,一个国际系统工程荣誉学会,命名为钱(钱)四名荣誉会员之一。<br />
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== Later life ==<br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<br />
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2009年10月31日,钱在北京去世,享年98岁。<br />
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[[File:钱学森图书馆.jpg|250px|thumb|Qian Xuesen Library, Xi'an Jiaotong University]]<br />
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A Chinese film production, Hsue-shen Tsien, directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in Asia and North America on December 11, 2011, and on March 2, 2012, it was released in China.<br />
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2011年12月11日,由张建亚导演、陈坤主演的中国电影《钱》在亚洲和北美同步上映,2012年3月2日在中国上映。<br />
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Qian retired in 1991 and lived quietly in Beijing, refusing to speak to Westerners.<ref>Peter Grier, "The forgotten 'spy' case of a rocket scientist" ''[[The Christian Science Monitor]]'' Vol. 92 Issue 244, November 2000</ref><br />
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<br />
In 1979, Qian was awarded Caltech's ''Distinguished Alumni Award'' for his achievements. Qian eventually received his award from Caltech, and with the help of his friend [[Frank Marble]] brought it to his home in a widely covered ceremony. Furthermore, in the early 1990s, the filing cabinets containing Qian's research work were offered to him by Caltech.<br />
<br />
Science fiction author Arthur C. Clarke, in his 1982 novel 2010: Odyssey Two, named a Chinese spaceship after him. The science fiction novel series The Expanse by James S. A. Corey also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel Noble House by James Clavell, the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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科幻小说作家亚瑟·查理斯·克拉克在他1982年的小说《2010: 奥德赛2》中,用他的名字命名了一艘中国的宇宙飞船。詹姆斯 · s · a · 科里(James s. a. Corey)的科幻小说系列《浩瀚无垠》(The exposure)也以他的名字命名了一艘火星宇宙飞船(MCRN Xuesen)。1981年,美籍华裔科学家詹姆斯 · 克拉维尔(James Clavell)投奔中国,帮助中国研制出了第一颗原子弹。在他的小说《贵族之家》(Noble House)中,余(Joseph Yu)博士是钱学森博士的虚构版本。<br />
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Qian was invited to visit the US by the [[American Institute of Aeronautics and Astronautics]] after the [[China-United States Relations|normalization of the Sino-US relationship]], but he refused the invitation, having wanted a formal apology for his detention. In a reminiscence published in 2002, Marble stated that he believed Qian had "lost faith in the American government" but that he had "always had very warm feelings for the American people."<ref>{{Cite web |url=http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |title=Tsien Revisited |access-date=2005-12-15 |archive-url=https://web.archive.org/web/20061211095210/http://pr.caltech.edu/periodicals/CaltechNews/articles/v36/tsien.html |archive-date=2006-12-11 |url-status=dead }}</ref><br />
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<br />
The Chinese government launched its manned space program in 1992, reportedly with some help from Russia due to their extended history in space. Qian's research was used as the basis for the [[Long March (rocket family)|Long March rocket]], which successfully launched the [[Shenzhou V]] mission in October 2003. The elderly Qian was able to watch China's first manned space mission on television from his hospital bed.<br />
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In 2008, he was named [[Aviation Week and Space Technology]] Person of the Year. The recognition was not intended as an honor, but is given to the person judged to have the greatest impact on aviation in the past year.<ref name="2008poy" /><ref>Hold Your Fire, Aviation Week and Space Technology, Vol. 168., No. 1, January 7, 2008, p.&nbsp;8.</ref> Furthermore, that year [[China Central Television]] named Qian as one of the eleven most inspiring people in China.<ref>Person of the Year, Aviation Week and Space Technology, Vol. 168., No. 12, March 24, 2008, p.&nbsp;22.</ref><br />
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In July 2009, the [[Omega Alpha Association]], an international systems engineering honor society, named Qian (H. S. Tsien) one of four Honorary Members.<ref name="Omega Alpha">http://www.omegalpha.org/honorary members/html</ref><br />
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On October 31, 2009, Qian died at the age of 98 in Beijing.<ref name="2009latimes">{{cite news |url = http://www.latimes.com/nation/la-me-qian-xuesen1-2009nov01-story.html |title = Qian Xuesen dies at 98; rocket scientist helped establish Jet Propulsion Laboratory |date = {{date|2009-11-01|dmy}} |newspaper = Los Angeles Times |first1 = Claire |last1 = Noland |access-date = 2015-02-02 }}</ref><ref>{{cite news |url = http://news.xinhuanet.com/english/2009-10/31/content_12365319.htm |title = China's "father of space technology" dies at 98 |agency = Xinhua |date = 2009-10-31 |accessdate = 2009-11-01 }}</ref><br />
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<br />
<br />
A Chinese film production, ''[[Hsue-shen Tsien (film)|Hsue-shen Tsien]]'', directed by Zhang Jianya and starring Chen Kun as Qian was simultaneously released in [[Asia]] and [[North America]] on December 11, 2011,<ref>{{YouTube|u0TVeM3HqU4|钱学森HD1280高清国语中英双字Hsue-shen Tsien (2012)}}</ref> and on March 2, 2012, it was released in China.<br />
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== In popular culture ==<br />
<br />
[[Science fiction]] author [[Arthur C. Clarke]], in his 1982 novel ''[[2010: Odyssey Two]],'' named a Chinese spaceship after him. The science fiction novel series ''[[The Expanse (novel series)|The Expanse]]'' by [[James S. A. Corey]] also named a Martian spaceship after him (MCRN Xuesen). In the 1981 novel '' [[Noble House (book)|Noble House]]'' by [[James Clavell]], the American-Chinese scientist who defected to China and helped develop the first atom bomb for China, Dr. Joseph Yu, is a fictionalized version of Dr. Qian Xuesen.<br />
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== Scientific papers ==<br />
<br />
* 1938: (with [[Theodore von Karman]]) "Boundary Layer in Compressible Fluids", ''Journal of Aeronautical Sciences'', April <br />
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* 1938: "Supersonic Flow Over an Inclined Body of Revolution", ''Journal of Aeronautical Sciences'', October<br />
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* 1938: (with [[Frank Malina]]) "Flight analysis of a Sounding Rocket with Special Reference to Propulsion by Successive Impulses", ''Journal of Aeronautical Sciences'', December<br />
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* 1939: [http://arc.aiaa.org/doi/abs/10.2514/8.916 Two-dimensional subsonic flow of compressible fluids], ''Journal of Aeronautical Sciences'' 6(10): 399–407.<ref>N. Coburn (1945) "The Kármán–Tsien Pressure-Volume Relation n the Two-dimensional Supersonic Flow of Compressible Fluids", ''Quarterly of Applied Mathematics'' 3: 106–16.</ref><br />
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* 1939: (with [[Theodore von Kármán]]) [http://arc.aiaa.org/doi/abs/10.2514/8.1019 The buckling of thin cylindrical shells under axial compression], ''Journal of Aeronautical Sciences'' 7(2):43 to 50.<br />
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* 1943: "Symmetrical Joukowsky Airfoils in shear flow", ''Quarterly of Applied Mathematics'', 1: 130–48.<br />
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* 1943: [http://arc.aiaa.org/doi/abs/10.2514/8.10985 On the Design of the Contraction Cone for a Wind Tunnel], ''Journal of Aeronautical Sciences'', 10(2): 68–70.<br />
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* 1945: (with Theodore von Kármán), "Lifting- line Theory for a Wing in Nonuniform Flow," ''Quarterly of Applied Mathematics'', 3: 1–11.<br />
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* 1946: "Similarity laws of hypersonic flows", [[MIT Journal of Mathematics and Physics]] 25: 247–251, {{mr |id = 0018074 }}.<br />
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* 1946: "Superaerodynamics, Mechanics of Rarefied Gases", ''Journal of the Aeronautical Sciences'', 13 (12)<br />
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* 1949: "Rockets and Other Thermal Jets Using Nuclear Energy", in ''The Science and Engineering of Nuclear Power'', Addison-Wesley, Vol. 2.<br />
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* 1950: "Instruction and Research at the Daniel and Florence Guggenheim Jet Propulsion Center", ''Journal of the American Rocket Society'', June 1950<br />
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* 1951: "Optimum Thrust Programming for a Sounding Rocket" (with Robert C. Evans), ''Journal of the American Rocket Society'' 21(5)<br />
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* 1952: "The Transfer Functions of Rocket Nozzles", ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "A Similarity Law for Stressing Rapidly Heated Thin-Walled Cylinders" (with C.M.Cheng), ''Journal of the American Rocket Society'' 22(3)<br />
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* 1952: "Automatic Navigation of a Long Range Rocket Vehicle", (with T.D.Adamson and E.L. Knuth) ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "A Method for Comparing the Performance of Power Plants for Vertical Flight", ''Journal of the American Rocket Society'' 22(4)<br />
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* 1952: "Serbo-Stabilization of Combustion in Rocket Motors", ''Journal of the American Rocket Society'' 22(5)<br />
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* 1953: "Physical Mechanics, a New Field in Engineering Science", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "The Properties of Pure Liquids", ''Journal of the American Rocket Society'' 23(1)<br />
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* 1953: "Take-Off from Satellite Orbit", ''Journal of the American Rocket Society'' 23(4)<br />
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* 1956: "The Poincaré-Lighthill-Kuo Method", ''Advances in Applied Mechanics'' 4: 281–349, {{mr |id = 0079929 }}.<br />
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* 1958: "The equations of gas dynamics", in ''Fundamentals of Gas Dynamics'' v. 3, [[Princeton University Press]], {{mr |id = 0097212 }}.<br />
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== Monographs ==<br />
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* 1954: {{cite book |url = https://babel.hathitrust.org/cgi/pt?id=uc1.b3734950;view=1up;seq=7 |title = Engineering Cybernetics |date = 4 April 2020 |publisher = McGraw Hill |oclc = 299574775 |location = New York, NY }}<br />
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** 1957: {{cite book |title = Technische Kybernetik |translator = Dr. H. Kaltenecker (into German) |publisher = Berliner Union |location = Stuttgart }}<br />
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* 2007: {{cite book |title = Hydrodynamics |year = 2007 |publisher = Jiaotong University Press |isbn = 978-7-313-04199-9 |type = manuscript facsimile }}<br />
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== See also ==<br />
<br />
{{Portal|China|Physics|Systems science|Engineering|Spaceflight|Aviation|World War II|Biography}}<br />
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* [[Aeronautics]]<br />
<br />
* [[Engineering cybernetics]]<br />
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* [[Jet Propulsion Laboratory]]<br />
<br />
* [[Theodore von Kármán]]<br />
<br />
* [[Chien-Shiung Wu]]<br />
<br />
* [[Ye Qisun]]<br />
<br />
* [[Guo Yonghuai]]<br />
<br />
Works cited<br />
<br />
引用作品<br />
<br />
* [[Hsue-Chu Tsien]]<br />
<br />
* [[McCarthyism]]<br />
<br />
* [[People's Liberation Army Rocket Force]]<br />
<br />
** [[Dongfeng (missile)]]<br />
<br />
* [[Chinese space program]]<br />
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** [[Long March (rocket family)]]<br />
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* [[China and weapons of mass destruction|Chinese nuclear program]]<br />
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** [[596 (nuclear test)|Project 596]]<br />
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** [[Test No. 6]]<br />
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* [[China Aerospace Science and Technology Corporation]] (formerly known as the Fifth Academy of the Ministry of Defense)<br />
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== References ==<br />
<br />
{{Reflist}}<br />
<br />
<br />
<br />
;Works cited<br />
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{{refbegin}}<br />
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* {{cite book |url = https://books.google.com/books?id=QtfndLdZhnAC |author-link = Iris Chang |last1 = Chang |first1 = Iris |title = Thread of the Silkworm |year = 1995 |publisher = BasicBooks |location = New York, NY |isbn = 978-0-465-08716-7 }}<br />
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* O'Donnell, Franklin (2002). [http://www.jpl.nasa.gov/about_JPL/jpl101.pdf JPL 101]. California Institute of Technology. JPL 400–1048.<br />
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* Harvey, Brian (2004). ''China's Space Program: From Conception to Manned Spaceflight''. Springer-Verlag. {{ISBN|978-1-85233-566-3}}.<br />
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* {{cite journal |last1 = Viorst |first1 = Milton |authorlink = Milton Viorst |title = The Bitter Tea of Dr. Tsien |date = September 1967 |journal = Esquire |url = |access-date = }}<br />
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* {{cite book|last1=Ryan|first1=William L.|last2=Summerlin|first2=Sam|title=The China Cloud: America's Tragic Blunder and China's Rise to Nuclear Power|place=Boston|publisher=Little, Brown and Company|year=1968|oclc=443363|lccn=68024245|ref=harv}}<br />
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{{refend}}<br />
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== External links ==<br />
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* [https://web.archive.org/web/20060502182903/http://www.astronautix.com/articles/china.htm China], Encyclopedia Astronautica<br />
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Category:2009 deaths<br />
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* [http://www.cnn.com/2003/TECH/space/10/03/china.space.timeline/ CNN.com timeline of China space program]<br />
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Category:20th-century Chinese engineers<br />
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类别: 20世纪中国工程师<br />
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* {{cite web |url = http://archives.caltech.edu/news/tsien.html |title = In the News: The father of Chinese rocketry |author = <!--Staff writer(s); no by-line.--> |date = |website = Caltech |access-date = {{Date|2015-02-02|dmy}} }}<br />
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<small>This page was moved from [[wikipedia:en:Qian Xuesen]]. Its edit history can be viewed at [[钱学森/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%94%A8%E6%88%B7:Henry&diff=19117用户:Henry2020-11-24T14:34:32Z<p>Henry:建立内容为“姓名:蔡笑天(Henry) 学校:山东大学 QQ:1920894929”的新页面</p>
<hr />
<div>姓名:蔡笑天(Henry)<br />
学校:山东大学<br />
QQ:1920894929</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=19046临界点(热力学)2020-11-22T14:25:47Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
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{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
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{{ordered list<br />
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{有序列表<br />
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|Subcritical [[ethane]], liquid and gas phase coexist.<br />
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|Subcritical ethane, liquid and gas phase coexist.<br />
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亚临界乙烷,液态和气态共存。<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
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|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
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|Supercritical ethane, fluid.<br />
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超临界乙烷,流体。<br />
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}}]]<br />
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In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
<br />
In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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在热力学中,<font color="#ff8000"> 临界点Critical point </font>(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
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== Liquid–vapor critical point液-汽临界点 ==<br />
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=== Overview 总览===<br />
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[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
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For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
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The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
<br />
The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
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右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
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In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
<br />
In water, the critical point occurs at and .<br />
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在水中,临界点发生在647.096K 和22.064MPa下。<br />
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In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
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In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
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在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,因为液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,所以它是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
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Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
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At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
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在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(<font color="#ff8000"> 临界等温线Critical isotherm</font>)中有一个固定的拐点。这意味着在临界点: <br />
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Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
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<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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左(frac { partial p }{ partial v } right) _ t = 0,<br />
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Elsevier.</ref><br />
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<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
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''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
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The critical isotherm with the critical point&nbsp;K<br />
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临界点 k 的临界等温线<br />
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: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
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在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
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: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
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有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
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''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
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Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
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临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
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The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
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=== History历史 ===<br />
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[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
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解决上述条件(∂p/∂V)T=0,对于范德华方程,可以计算临界点为<br />
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The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
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<math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
8 a }{27Rb } ,<br />
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* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
<br />
\quad V_\text{c} = 3nb,<br />
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3nb,<br />
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* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
27b ^ 2} . </math > <br />
<br />
* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
<br />
然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律<br />
<br />
=== Theory理论 ===<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
<br />
为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
<br />
<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
如果你想知道更多的信息,请访问我的网站,<br />
<br />
: <math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
<br />
The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
<br />
对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
<br />
<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
<br />
For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
<br />
对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
<br />
<br />
: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
<center><br />
<br />
< 中心 > <br />
<br />
<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
{ | class = “ wikitable sortable” style = “ text-align: center; ”<br />
<br />
The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
<br />
|-<br />
<br />
|-<br />
<br />
<br />
<br />
! Substance<br />
<br />
!物质<br />
<br />
For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
<br />
! Critical temperature<br />
<br />
!临界温度<br />
<br />
<br />
<br />
! Critical pressure (absolute)<br />
<br />
!临界压力(绝对值)<br />
<br />
=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
<br />
|-<br />
<br />
|-<br />
<br />
{{see also|Critical points of the elements (data page)}}<br />
<br />
| Argon<br />
<br />
| 氩气<br />
<br />
<center><br />
<br />
| }}<br />
<br />
| }}<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
<br />
| Ammonia (NH<sub>3</sub>)<br />
<br />
| 氨(NH < sub > 3 </sub >)<br />
<br />
! Critical temperature<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0652|{{convert|652|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Mercury (element)|Mercury]]<br />
<br />
| Iron<br />
<br />
铁<br />
<br />
| {{sort|1750.1|{{convert|1476.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|1720|{{convert|1720|atm|kPa|abbr=on}}}}<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfur]]<br />
<br />
| Gold<br />
<br />
| 黄金<br />
<br />
| {{sort|1314.00|{{convert|1040.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0207|{{convert|207|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Iron]]<br />
<br />
| Aluminium<br />
<br />
| 铝<br />
<br />
| {{sort|8500|{{convert|8227|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Gold]]<br />
<br />
| Water (H<sub>2</sub>O)<br />
<br />
| 水(h < sub > 2 </sub > o)<br />
<br />
| {{sort|7250|{{convert|6977|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|5000|{{convert|5000|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|- <br />
<br />
|-<br />
<br />
| [[Aluminium]]<br />
<br />
|}<br />
<br />
|}<br />
<br />
| {{sort|7850|{{convert|7577|C|K}}}}<br />
<br />
</center><br />
<br />
</center ><br />
<br />
|<br />
<br />
|-<br />
<br />
| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
<br />
| {{sort|0647.096|{{convert|373.946|C|K}}}}<br />
<br />
A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
<br />
典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
<br />
| {{sort|0217.7|{{convert|217.7|atm|kPa|abbr=on}}}}<br />
<br />
The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
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溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
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From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
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从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
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[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
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The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
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===Mathematical definition数学定义===<br />
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From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
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==See also参见==<br />
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* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
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== Footnotes脚注 ==<br />
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{{Reflist|38em}}<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
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== References参考 ==<br />
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*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
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Category:Condensed matter physics<br />
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类别: 凝聚态物理学<br />
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==External links外部链接==<br />
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Category:Conformal field theory<br />
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类别: 共形场论<br />
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* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
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Category:Critical phenomena<br />
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范畴: 关键现象<br />
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*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
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Category:Phase transitions<br />
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类别: 阶段转变<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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Category:Renormalization group<br />
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类别: 重整化群<br />
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Category:Threshold temperatures<br />
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类别: 临界温度<br />
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Category:Gases<br />
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分类: 气体<br />
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<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=19045临界点(热力学)2020-11-22T14:23:00Z<p>Henry:</p>
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<div>此词条暂由Henry翻译<br />
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{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
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|Subcritical [[ethane]], liquid and gas phase coexist.<br />
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|Subcritical ethane, liquid and gas phase coexist.<br />
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亚临界乙烷,液态和气态共存。<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
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|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
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|Supercritical ethane, fluid.<br />
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超临界乙烷,流体。<br />
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In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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在热力学中,<font color="#ff8000"> 临界点Critical point </font>(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
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== Liquid–vapor critical point液-汽临界点 ==<br />
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=== Overview 总览===<br />
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[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
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For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
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The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
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The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
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右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
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In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
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In water, the critical point occurs at and .<br />
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在水中,临界点发生在 和。<br />
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In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
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In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
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在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,因为液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,所以它是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
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Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
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At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
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在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(临界等温线)中有一个固定的拐点。这意味着在临界点: <br />
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Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
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<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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左(frac { partial p }{ partial v } right) _ t = 0,<br />
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Elsevier.</ref><br />
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<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
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''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
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The critical isotherm with the critical point&nbsp;K<br />
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临界点 k 的临界等温线<br />
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: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
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在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
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: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
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有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
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''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
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Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
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临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
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The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
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=== History历史 ===<br />
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[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
<br />
解决上述条件(∂p/∂V)T=0,对于范德华方程,可以计算临界点为<br />
<br />
The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
<br />
<math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
8 a }{27Rb } ,<br />
<br />
* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
3nb,<br />
<br />
* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
27b ^ 2} . </math > <br />
<br />
* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
<br />
然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律<br />
<br />
=== Theory理论 ===<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
<br />
为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
<br />
<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
如果你想知道更多的信息,请访问我的网站,<br />
<br />
: <math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
<br />
The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
<br />
对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
<br />
<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
<br />
For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
<br />
对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
<br />
<br />
: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
<center><br />
<br />
< 中心 > <br />
<br />
<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
{ | class = “ wikitable sortable” style = “ text-align: center; ”<br />
<br />
The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
<br />
|-<br />
<br />
|-<br />
<br />
<br />
<br />
! Substance<br />
<br />
!物质<br />
<br />
For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
<br />
! Critical temperature<br />
<br />
!临界温度<br />
<br />
<br />
<br />
! Critical pressure (absolute)<br />
<br />
!临界压力(绝对值)<br />
<br />
=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
<br />
|-<br />
<br />
|-<br />
<br />
{{see also|Critical points of the elements (data page)}}<br />
<br />
| Argon<br />
<br />
| 氩气<br />
<br />
<center><br />
<br />
| }}<br />
<br />
| }}<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
<br />
| Ammonia (NH<sub>3</sub>)<br />
<br />
| 氨(NH < sub > 3 </sub >)<br />
<br />
! Critical temperature<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
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| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
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A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
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典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
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The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
<br />
溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
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From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
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从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
<br />
<br />
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[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
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The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
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===Mathematical definition数学定义===<br />
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From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
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==See also参见==<br />
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* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
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== Footnotes脚注 ==<br />
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{{Reflist|38em}}<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
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== References参考 ==<br />
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*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
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Category:Condensed matter physics<br />
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类别: 凝聚态物理学<br />
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==External links外部链接==<br />
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Category:Conformal field theory<br />
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类别: 共形场论<br />
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* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
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Category:Critical phenomena<br />
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范畴: 关键现象<br />
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*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
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Category:Phase transitions<br />
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类别: 阶段转变<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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Category:Renormalization group<br />
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Category:Threshold temperatures<br />
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类别: 临界温度<br />
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Category:Gases<br />
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分类: 气体<br />
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<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%95%B4%E4%BD%93%E8%AE%BA_Holism&diff=18819整体论 Holism2020-11-20T15:02:35Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
'''Holism''' (from [[Ancient Greek|Greek]] {{lang|grc|ὅλος}} ''holos'' "all, whole, entire") is the idea that various [[system]]s (e.g. physical, biological, social) should be viewed as wholes, not merely as a collection of parts.<ref>{{Citation | first = Barry | last = Oshry | title = Seeing Systems: Unlocking the Mysteries of Organizational Life | publisher = Berrett-Koehler | year = 2008}}.</ref><ref>{{Citation | first = Sunny Y | last = Auyang | title = Foundations of Complex-system Theories: in Economics, Evolutionary Biology, and Statistical Physics | publisher = Cambridge University Press | year = 1999}}.</ref> The term "holism" was coined by [[Jan Smuts]] in his 1926 book ''[[Holism and Evolution]]''.<ref name=oed>"holism, n." OED Online, [[Oxford University Press]], September 2019, www.oed.com/view/Entry/87726. Accessed 23 October 2019.</ref><br />
<br />
Holism (from Greek holos "all, whole, entire") is the idea that various systems (e.g. physical, biological, social) should be viewed as wholes, not merely as a collection of parts. The term "holism" was coined by Jan Smuts in his 1926 book Holism and Evolution.<br />
<br />
<font color="#ff8000"> 整体主义Holism</font>(源自希腊holos“all,whole,entire”)是一种观点,即各种系统(例如物理的、生物的、社会的)应该被视为整体,而不仅仅是部分的集合。“整体主义”这个词是扬·斯密茨在1926年出版的《整体主义与进化》一书中提出的。 <br />
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==Meaning含义==<br />
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The exact meaning of "holism" depends on context. Smuts originally used "holism" to refer to the tendency in nature to produce wholes from the ordered grouping of unit structures.<ref name=oed /> However, in common usage, "holism" usually refers to the idea that a whole is greater than the sum of its parts.<ref name=poynton>J. C. Poynton (1987) SMUTS'S HOLISM AND EVOLUTION SIXTY YEARS ON, Transactions of the Royal Society of South Africa, 46:3, 181-189, DOI:10.1080/00359198709520121</ref> In this sense, "holism" may also be spelled "'''wholism'''", and it may be contrasted with [[reductionism]] or [[atomism]].<ref> "wholism, n." OED Online, Oxford University Press, September 2019, www.oed.com/view/Entry/228738. Accessed 23 October 2019.</ref><br />
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The exact meaning of "holism" depends on context. Smuts originally used "holism" to refer to the tendency in nature to produce wholes from the ordered grouping of unit structures. In this sense, "holism" may also be spelled "wholism", and it may be contrasted with reductionism or atomism.<br />
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“整体论”的确切含义取决于语境。Smuts最初用“整体论”来指自然界中从单元结构的有序组合中产生整体的倾向。在这个意义上,“整体论”也可以拼写为“整体主义”,它可以与还原论或原子论形成对比。<br />
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=== Diet and health饮食与健康 ===<br />
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The term holistic when applied to [[Diet (nutrition)|diet]] or medical [[health]] refers to [[intuitive]] approach to [[food]], [[eating]], or [[Lifestyle (sociology)|lifestyle]].<ref name="Chesak 2018">{{cite web | last=Chesak | first=Jennifer | title=The No BS Guide to Holistic, Healthier Eating | website=Healthline | date=October 23, 2018 | url=https://www.healthline.com/health/food-nutrition/how-to-start-intuitive-eating | access-date=August 15, 2020}}</ref> One example is in the context of [[holistic medicine]], "holism" refers to treating all aspects of a person's health, including psychological and societal factors, rather than only his/her physical conditions or symptoms.<ref>"holistic, adj." OED Online, Oxford University Press, September 2019, www.oed.com/view/Entry/87727. Accessed 23 October 2019.</ref> In this sense, holism may also be called "'''holiatry'''".<ref>[https://www.dictionary.com/browse/holism Dictionary.com: holism]</ref> Several approaches are used by [[medical doctors]], [[dietitian]]s, and [[religion|religious]] institutions, usually recommended based on an individual basis.<ref name="Fenton 2010">{{cite web | last=Fenton | first=Crystal | title=Holistic Diet | website=LIVESTRONG.COM | date=April 16, 2010 | url=https://www.livestrong.com/article/107401-holistic-diet/ | access-date=August 15, 2020}}</ref><ref name="doctoroz.com 2011">{{cite web | title=28-Day Holistic Health Overhaul | website=doctoroz.com | date=January 27, 2011 | url=https://www.doctoroz.com/article/28-day-holistic-health-overhaul | access-date=August 15, 2020}}</ref><ref name="TODAY.com 2016">{{cite web | title=8 foods for a longer, healthier life | website=TODAY.com | date=October 21, 2016 | url=https://www.today.com/health/eat-adventist-8-foods-longer-healthier-life-t13901 | access-date=August 15, 2020}}</ref> Adherents of religious institutions, that practice a holistic dietary and health approach, have been shown have longer lifespans than those of surrounding populations, including [[Hinduism]],<ref name="Fenton 2010"></ref> [[Shinto]],<ref name="Eesti Rahvaluule">{{cite web | title=FACING THE SPIRITS: ILLNESS AND HEALING IN A JAPANESE COMMUNITY | website=Eesti Rahvaluule | url=http://www.folklore.ee/rl/pubte/ee/usund/ingl/kalland.html | access-date=October 9, 2020}}</ref> and the [[Seventh-Day Adventist Church]].<ref name="TODAY.com 2016"></ref><br />
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The term holistic when applied to diet or medical health refers to intuitive approach to food, eating, or lifestyle. One example is in the context of holistic medicine, "holism" refers to treating all aspects of a person's health, including psychological and societal factors, rather than only his/her physical conditions or symptoms. In this sense, holism may also be called "holiatry". Several approaches are used by medical doctors, dietitians, and religious institutions, usually recommended based on an individual basis. Adherents of religious institutions, that practice a holistic dietary and health approach, have been shown have longer lifespans than those of surrounding populations, including Hinduism, and the Seventh-Day Adventist Church.<ref name="TODAY.com 2016"></ref><br />
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当用于饮食或医疗健康时,术语“整体”指的是对食物、饮食或生活方式的直觉方法。一个例子是在整体医学的背景下,“整体论”是指治疗一个人健康的所有方面,包括心理和社会因素,而不仅仅是他/她的身体状况或症状。从这个意义上讲,整体主义也可以称为“整体主义”。医生、营养师和宗教机构通常根据个人情况推荐几种方法。宗教机构的信徒,实行全面的饮食和健康方法,已经被证明比周围的人口,包括印度教和基督复临安息日会的信徒寿命更长。 <br />
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== See also参见 ==<br />
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*[[Antireductionism]]<br />
反还原论<br />
*[[Emergentism]]<br />
紧急情况论<br />
*[[Gaia hypothesis]]<br />
盖亚假说<br />
*[[Holistic education]]<br />
整体教育<br />
*[[Holism in science]]<br />
科学中的整体论<br />
* [[Monism]]<br />
一元论<br />
*[[Organicism]]<br />
有机主义<br />
*[[Synergy]]<br />
协同作用 <br />
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==References参考==<br />
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{{reflist}}<br />
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== Further reading 拓展阅读==<br />
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* Fodor, Jerry, and Ernst Lepore, ''Holism: A Shopper's Guide'' Wiley. New York. 1992<br />
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* Phillips, D.C. ''Holistic Thought in Social Science''. Stanford University Press. Stanford. 1976.<br />
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== External links外部链接 ==<br />
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类别: 涌现<br />
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类别: Jan Smuts<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Holism]]. Its edit history can be viewed at [[整体论/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=18772临界点(热力学)2020-11-19T08:15:18Z<p>Henry:</p>
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<div>此词条暂由Henry翻译<br />
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{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
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|Subcritical [[ethane]], liquid and gas phase coexist.<br />
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|Subcritical ethane, liquid and gas phase coexist.<br />
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亚临界乙烷,液态和气态共存。<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
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|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
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|Supercritical ethane, fluid.<br />
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超临界乙烷,流体。<br />
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In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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在热力学中,<font color="#ff8000"> 临界点Critical point </font>(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
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== Liquid–vapor critical point液-汽临界点 ==<br />
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=== Overview 总览===<br />
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[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
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For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
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The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
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The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
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右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
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In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
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In water, the critical point occurs at and .<br />
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在水中,临界点发生在 和。<br />
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In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
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In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
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在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
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Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
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At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
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在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(临界等温线)中有一个固定的拐点。这意味着在临界点: <br />
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Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
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<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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左(frac { partial p }{ partial v } right) _ t = 0,<br />
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Elsevier.</ref><br />
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<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
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''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
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The critical isotherm with the critical point&nbsp;K<br />
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临界点 k 的临界等温线<br />
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: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
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在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
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: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
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有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
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''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
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Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
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临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
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The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
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=== History历史 ===<br />
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[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
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解决上述条件(∂p/∂V)T=0,对于范德华方程,可以计算临界点为<br />
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The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
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<math>T_\text{c} = \frac{8a}{27Rb},<br />
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8 a }{27Rb } ,<br />
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* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
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\quad V_\text{c} = 3nb,<br />
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3nb,<br />
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* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
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\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
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27b ^ 2} . </math > <br />
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* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
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然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律<br />
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=== Theory理论 ===<br />
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To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
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为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
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<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
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如果你想知道更多的信息,请访问我的网站,<br />
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: <math>T_\text{c} = \frac{8a}{27Rb},<br />
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\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
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4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
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\quad V_\text{c} = 3nb,<br />
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\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
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4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
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\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
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However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
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The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
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对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
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To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
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For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
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对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
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: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
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\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
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\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
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The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
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For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
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=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
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{{see also|Critical points of the elements (data page)}}<br />
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! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
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| Ammonia (NH<sub>3</sub>)<br />
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! Critical temperature<br />
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<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0652|{{convert|652|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Mercury (element)|Mercury]]<br />
<br />
| Iron<br />
<br />
铁<br />
<br />
| {{sort|1750.1|{{convert|1476.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|1720|{{convert|1720|atm|kPa|abbr=on}}}}<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfur]]<br />
<br />
| Gold<br />
<br />
| 黄金<br />
<br />
| {{sort|1314.00|{{convert|1040.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0207|{{convert|207|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Iron]]<br />
<br />
| Aluminium<br />
<br />
| 铝<br />
<br />
| {{sort|8500|{{convert|8227|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Gold]]<br />
<br />
| Water (H<sub>2</sub>O)<br />
<br />
| 水(h < sub > 2 </sub > o)<br />
<br />
| {{sort|7250|{{convert|6977|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|5000|{{convert|5000|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|- <br />
<br />
|-<br />
<br />
| [[Aluminium]]<br />
<br />
|}<br />
<br />
|}<br />
<br />
| {{sort|7850|{{convert|7577|C|K}}}}<br />
<br />
</center><br />
<br />
</center ><br />
<br />
|<br />
<br />
|-<br />
<br />
| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
<br />
| {{sort|0647.096|{{convert|373.946|C|K}}}}<br />
<br />
A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
<br />
典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
<br />
| {{sort|0217.7|{{convert|217.7|atm|kPa|abbr=on}}}}<br />
<br />
The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
<br />
溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
<br />
|- <br />
<br />
|}<br />
<br />
</center><br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
<br />
从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
<br />
<br />
<br />
[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
<br />
The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
<br />
<br />
===Mathematical definition数学定义===<br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
<br />
<br />
==See also参见==<br />
<br />
<br />
<br />
{{colbegin}}<br />
<br />
* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
{{colend}}<br />
<br />
<br />
<br />
== Footnotes脚注 ==<br />
<br />
{{Reflist|38em}}<br />
<br />
| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
<br />
| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
<br />
<br />
<br />
== References参考 ==<br />
<br />
*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
<br />
<br />
<br />
Category:Condensed matter physics<br />
<br />
类别: 凝聚态物理学<br />
<br />
==External links外部链接==<br />
<br />
Category:Conformal field theory<br />
<br />
类别: 共形场论<br />
<br />
* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
<br />
Category:Critical phenomena<br />
<br />
范畴: 关键现象<br />
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*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
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Category:Phase transitions<br />
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类别: 阶段转变<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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Category:Renormalization group<br />
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类别: 重整化群<br />
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Category:Threshold temperatures<br />
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类别: 临界温度<br />
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{{Phase_of_matter}}<br />
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Category:Gases<br />
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分类: 气体<br />
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<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=18771临界点(热力学)2020-11-19T08:14:16Z<p>Henry:</p>
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<div>此词条暂由Henry翻译<br />
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{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
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|Subcritical [[ethane]], liquid and gas phase coexist.<br />
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|Subcritical ethane, liquid and gas phase coexist.<br />
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亚临界乙烷,液态和气态共存。<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
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|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
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|Supercritical ethane, fluid.<br />
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超临界乙烷,流体。<br />
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In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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在热力学中,临界点(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
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== Liquid–vapor critical point液-汽临界点 ==<br />
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=== Overview 总览===<br />
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[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
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For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
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The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
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The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
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右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
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In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
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In water, the critical point occurs at and .<br />
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在水中,临界点发生在 和。<br />
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In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
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In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
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在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
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Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
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At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
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在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(临界等温线)中有一个固定的拐点。这意味着在临界点: <br />
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Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
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<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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左(frac { partial p }{ partial v } right) _ t = 0,<br />
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Elsevier.</ref><br />
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<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
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''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
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The critical isotherm with the critical point&nbsp;K<br />
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临界点 k 的临界等温线<br />
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: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
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在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
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: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
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有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
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''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
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Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
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临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
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The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
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=== History历史 ===<br />
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[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
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解决上述条件(∂p/∂V)T=0,对于范德华方程,可以计算临界点为<br />
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The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
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<math>T_\text{c} = \frac{8a}{27Rb},<br />
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8 a }{27Rb } ,<br />
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* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
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\quad V_\text{c} = 3nb,<br />
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3nb,<br />
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* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
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\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
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27b ^ 2} . </math > <br />
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* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
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然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律<br />
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=== Theory理论 ===<br />
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To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
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为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
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<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
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如果你想知道更多的信息,请访问我的网站,<br />
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: <math>T_\text{c} = \frac{8a}{27Rb},<br />
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\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
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4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
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\quad V_\text{c} = 3nb,<br />
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\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
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4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
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\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
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However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
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The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
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对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
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To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
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For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
<br />
对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
<br />
<br />
: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
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<center><br />
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< 中心 > <br />
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<br />
{| class="wikitable sortable" style="text-align: center;"<br />
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{ | class = “ wikitable sortable” style = “ text-align: center; ”<br />
<br />
The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
<br />
|-<br />
<br />
|-<br />
<br />
<br />
<br />
! Substance<br />
<br />
!物质<br />
<br />
For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
<br />
! Critical temperature<br />
<br />
!临界温度<br />
<br />
<br />
<br />
! Critical pressure (absolute)<br />
<br />
!临界压力(绝对值)<br />
<br />
=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
<br />
|-<br />
<br />
|-<br />
<br />
{{see also|Critical points of the elements (data page)}}<br />
<br />
| Argon<br />
<br />
| 氩气<br />
<br />
<center><br />
<br />
| }}<br />
<br />
| }}<br />
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{| class="wikitable sortable" style="text-align: center;"<br />
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| }}<br />
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| }}<br />
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|-<br />
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|-<br />
<br />
|-<br />
<br />
! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
<br />
| Ammonia (NH<sub>3</sub>)<br />
<br />
| 氨(NH < sub > 3 </sub >)<br />
<br />
! Critical temperature<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0652|{{convert|652|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Mercury (element)|Mercury]]<br />
<br />
| Iron<br />
<br />
铁<br />
<br />
| {{sort|1750.1|{{convert|1476.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|1720|{{convert|1720|atm|kPa|abbr=on}}}}<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfur]]<br />
<br />
| Gold<br />
<br />
| 黄金<br />
<br />
| {{sort|1314.00|{{convert|1040.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0207|{{convert|207|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Iron]]<br />
<br />
| Aluminium<br />
<br />
| 铝<br />
<br />
| {{sort|8500|{{convert|8227|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Gold]]<br />
<br />
| Water (H<sub>2</sub>O)<br />
<br />
| 水(h < sub > 2 </sub > o)<br />
<br />
| {{sort|7250|{{convert|6977|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|5000|{{convert|5000|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|- <br />
<br />
|-<br />
<br />
| [[Aluminium]]<br />
<br />
|}<br />
<br />
|}<br />
<br />
| {{sort|7850|{{convert|7577|C|K}}}}<br />
<br />
</center><br />
<br />
</center ><br />
<br />
|<br />
<br />
|-<br />
<br />
| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
<br />
| {{sort|0647.096|{{convert|373.946|C|K}}}}<br />
<br />
A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
<br />
典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
<br />
| {{sort|0217.7|{{convert|217.7|atm|kPa|abbr=on}}}}<br />
<br />
The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
<br />
溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
<br />
|- <br />
<br />
|}<br />
<br />
</center><br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
<br />
从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
<br />
<br />
<br />
[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
<br />
The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
<br />
<br />
===Mathematical definition数学定义===<br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
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==See also参见==<br />
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{{colbegin}}<br />
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* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
{{colend}}<br />
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== Footnotes脚注 ==<br />
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{{Reflist|38em}}<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
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== References参考 ==<br />
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*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
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Category:Condensed matter physics<br />
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类别: 凝聚态物理学<br />
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==External links外部链接==<br />
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Category:Conformal field theory<br />
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类别: 共形场论<br />
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* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
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Category:Critical phenomena<br />
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范畴: 关键现象<br />
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*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
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Category:Phase transitions<br />
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类别: 阶段转变<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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Category:Renormalization group<br />
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类别: 重整化群<br />
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Category:Threshold temperatures<br />
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类别: 临界温度<br />
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{{Phase_of_matter}}<br />
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Category:Gases<br />
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分类: 气体<br />
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<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=18770临界点(热力学)2020-11-19T08:14:06Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
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{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
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{{ordered list<br />
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{有序列表<br />
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|Subcritical [[ethane]], liquid and gas phase coexist.<br />
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|Subcritical ethane, liquid and gas phase coexist.<br />
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亚临界乙烷,液态和气态共存。<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
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|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
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|Supercritical ethane, fluid.<br />
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超临界乙烷,流体。<br />
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}}]]<br />
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In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
<br />
In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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在热力学中,<font color="#ff8000"> 临界点Critical point</font>(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
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== Liquid–vapor critical point液-汽临界点 ==<br />
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=== Overview 总览===<br />
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[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
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For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
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The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
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The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
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右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
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In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
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In water, the critical point occurs at and .<br />
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在水中,临界点发生在 和。<br />
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In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
<br />
In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
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在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
<br />
Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
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At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
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在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(临界等温线)中有一个固定的拐点。这意味着在临界点: <br />
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Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
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<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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左(frac { partial p }{ partial v } right) _ t = 0,<br />
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Elsevier.</ref><br />
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<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
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''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
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The critical isotherm with the critical point&nbsp;K<br />
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临界点 k 的临界等温线<br />
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: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
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在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
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: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
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有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
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''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
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Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
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临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
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<br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
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The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
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=== History历史 ===<br />
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[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
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解决上述条件(∂p/∂V)T=0,对于范德华方程,可以计算临界点为<br />
<br />
The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
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<math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
8 a }{27Rb } ,<br />
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* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
<br />
\quad V_\text{c} = 3nb,<br />
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3nb,<br />
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* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
27b ^ 2} . </math > <br />
<br />
* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
<br />
然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律<br />
<br />
=== Theory理论 ===<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
<br />
为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
<br />
<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
如果你想知道更多的信息,请访问我的网站,<br />
<br />
: <math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
<br />
The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
<br />
对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
<br />
<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
<br />
For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
<br />
对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
<br />
<br />
: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
<center><br />
<br />
< 中心 > <br />
<br />
<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
{ | class = “ wikitable sortable” style = “ text-align: center; ”<br />
<br />
The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
<br />
|-<br />
<br />
|-<br />
<br />
<br />
<br />
! Substance<br />
<br />
!物质<br />
<br />
For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
<br />
! Critical temperature<br />
<br />
!临界温度<br />
<br />
<br />
<br />
! Critical pressure (absolute)<br />
<br />
!临界压力(绝对值)<br />
<br />
=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
<br />
|-<br />
<br />
|-<br />
<br />
{{see also|Critical points of the elements (data page)}}<br />
<br />
| Argon<br />
<br />
| 氩气<br />
<br />
<center><br />
<br />
| }}<br />
<br />
| }}<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
<br />
| Ammonia (NH<sub>3</sub>)<br />
<br />
| 氨(NH < sub > 3 </sub >)<br />
<br />
! Critical temperature<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0652|{{convert|652|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Mercury (element)|Mercury]]<br />
<br />
| Iron<br />
<br />
铁<br />
<br />
| {{sort|1750.1|{{convert|1476.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|1720|{{convert|1720|atm|kPa|abbr=on}}}}<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfur]]<br />
<br />
| Gold<br />
<br />
| 黄金<br />
<br />
| {{sort|1314.00|{{convert|1040.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0207|{{convert|207|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Iron]]<br />
<br />
| Aluminium<br />
<br />
| 铝<br />
<br />
| {{sort|8500|{{convert|8227|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Gold]]<br />
<br />
| Water (H<sub>2</sub>O)<br />
<br />
| 水(h < sub > 2 </sub > o)<br />
<br />
| {{sort|7250|{{convert|6977|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|5000|{{convert|5000|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|- <br />
<br />
|-<br />
<br />
| [[Aluminium]]<br />
<br />
|}<br />
<br />
|}<br />
<br />
| {{sort|7850|{{convert|7577|C|K}}}}<br />
<br />
</center><br />
<br />
</center ><br />
<br />
|<br />
<br />
|-<br />
<br />
| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
<br />
| {{sort|0647.096|{{convert|373.946|C|K}}}}<br />
<br />
A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
<br />
典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
<br />
| {{sort|0217.7|{{convert|217.7|atm|kPa|abbr=on}}}}<br />
<br />
The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
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溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
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From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
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从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
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[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
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The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
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===Mathematical definition数学定义===<br />
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From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
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==See also参见==<br />
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* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
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== Footnotes脚注 ==<br />
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{{Reflist|38em}}<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
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== References参考 ==<br />
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*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
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Category:Condensed matter physics<br />
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类别: 凝聚态物理学<br />
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==External links外部链接==<br />
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Category:Conformal field theory<br />
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类别: 共形场论<br />
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* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
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Category:Critical phenomena<br />
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范畴: 关键现象<br />
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*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
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Category:Phase transitions<br />
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类别: 阶段转变<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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Category:Renormalization group<br />
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类别: 重整化群<br />
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Category:Threshold temperatures<br />
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类别: 临界温度<br />
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Category:Gases<br />
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分类: 气体<br />
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<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=18769临界点(热力学)2020-11-19T08:12:42Z<p>Henry:/* History历史 */</p>
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<div>此词条暂由Henry翻译<br />
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{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
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|Subcritical [[ethane]], liquid and gas phase coexist.<br />
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|Subcritical ethane, liquid and gas phase coexist.<br />
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亚临界乙烷,液态和气态共存。<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
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| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
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|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
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|Supercritical ethane, fluid.<br />
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超临界乙烷,流体。<br />
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In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
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在热力学中,临界点(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
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== Liquid–vapor critical point液-汽临界点 ==<br />
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=== Overview 总览===<br />
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[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
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在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
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For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
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为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
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The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
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The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
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右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
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In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
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In water, the critical point occurs at and .<br />
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在水中,临界点发生在 和。<br />
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In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
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In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
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在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
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Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
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At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
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在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(临界等温线)中有一个固定的拐点。这意味着在临界点: <br />
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Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
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<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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左(frac { partial p }{ partial v } right) _ t = 0,<br />
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Elsevier.</ref><br />
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<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
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''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
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The critical isotherm with the critical point&nbsp;K<br />
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临界点 k 的临界等温线<br />
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: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
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Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
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在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
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: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
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有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
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''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
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Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
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临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
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Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
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The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
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临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
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=== History历史 ===<br />
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[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
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Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
<br />
解决上述条件(∂p/∂V)T=0,对于范德华方程,可以计算临界点为<br />
<br />
The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
<br />
<math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
8 a }{27Rb } ,<br />
<br />
* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
3nb,<br />
<br />
* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
27b ^ 2} . </math > <br />
<br />
* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
<br />
然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律<br />
<br />
=== Theory理论 ===<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
<br />
为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
<br />
<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
如果你想知道更多的信息,请访问我的网站,<br />
<br />
: <math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
<br />
The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
<br />
对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
<br />
<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
<br />
For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
<br />
对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
<br />
<br />
: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
<center><br />
<br />
< 中心 > <br />
<br />
<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
{ | class = “ wikitable sortable” style = “ text-align: center; ”<br />
<br />
The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
<br />
|-<br />
<br />
|-<br />
<br />
<br />
<br />
! Substance<br />
<br />
!物质<br />
<br />
For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
<br />
! Critical temperature<br />
<br />
!临界温度<br />
<br />
<br />
<br />
! Critical pressure (absolute)<br />
<br />
!临界压力(绝对值)<br />
<br />
=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
<br />
|-<br />
<br />
|-<br />
<br />
{{see also|Critical points of the elements (data page)}}<br />
<br />
| Argon<br />
<br />
| 氩气<br />
<br />
<center><br />
<br />
| }}<br />
<br />
| }}<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
<br />
| Ammonia (NH<sub>3</sub>)<br />
<br />
| 氨(NH < sub > 3 </sub >)<br />
<br />
! Critical temperature<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
<br />
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| {{sort|0652|{{convert|652|atm|kPa|abbr=on}}}}<br />
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| }}<br />
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|-<br />
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|-<br />
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| [[Mercury (element)|Mercury]]<br />
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| Iron<br />
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铁<br />
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| {{sort|1750.1|{{convert|1476.9|C|K}}}}<br />
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| }}<br />
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|-<br />
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| [[Sulfur]]<br />
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| Gold<br />
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| 黄金<br />
<br />
| {{sort|1314.00|{{convert|1040.85|C|K}}}}<br />
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| }}<br />
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| }}<br />
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| {{sort|0207|{{convert|207|atm|kPa|abbr=on}}}}<br />
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| }}<br />
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| }}<br />
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|-<br />
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|-<br />
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|-<br />
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| }}<br />
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| 水(h < sub > 2 </sub > o)<br />
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| {{sort|7250|{{convert|6977|C|K}}}}<br />
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| }}<br />
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|-<br />
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|}<br />
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</center><br />
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</center ><br />
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|<br />
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|-<br />
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| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
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| {{sort|0647.096|{{convert|373.946|C|K}}}}<br />
<br />
A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
<br />
典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
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| {{sort|0217.7|{{convert|217.7|atm|kPa|abbr=on}}}}<br />
<br />
The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
<br />
溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
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From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
<br />
从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
<br />
<br />
<br />
[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
<br />
The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
<br />
<br />
===Mathematical definition数学定义===<br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
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==See also参见==<br />
<br />
<br />
<br />
{{colbegin}}<br />
<br />
* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
{{colend}}<br />
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<br />
== Footnotes脚注 ==<br />
<br />
{{Reflist|38em}}<br />
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| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
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<br />
== References参考 ==<br />
<br />
*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
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Category:Condensed matter physics<br />
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类别: 凝聚态物理学<br />
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==External links外部链接==<br />
<br />
Category:Conformal field theory<br />
<br />
类别: 共形场论<br />
<br />
* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
<br />
Category:Critical phenomena<br />
<br />
范畴: 关键现象<br />
<br />
*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
<br />
Category:Phase transitions<br />
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类别: 阶段转变<br />
<br />
| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
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Category:Renormalization group<br />
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类别: 重整化群<br />
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Category:Threshold temperatures<br />
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类别: 临界温度<br />
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{{Phase_of_matter}}<br />
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Category:Gases<br />
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分类: 气体<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=18768临界点(热力学)2020-11-19T08:11:32Z<p>Henry:/* External links */</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
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{{ordered list<br />
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{{ordered list<br />
<br />
{有序列表<br />
<br />
|Subcritical [[ethane]], liquid and gas phase coexist.<br />
<br />
|Subcritical ethane, liquid and gas phase coexist.<br />
<br />
亚临界乙烷,液态和气态共存。<br />
<br />
|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
<br />
|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
<br />
| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
<br />
|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
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|Supercritical ethane, fluid.<br />
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超临界乙烷,流体。<br />
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}}]]<br />
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}}]]<br />
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}}]]<br />
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In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
<br />
In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
<br />
在热力学中,临界点(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
<br />
<br />
<br />
== Liquid–vapor critical point液-汽临界点 ==<br />
<br />
<br />
<br />
=== Overview 总览===<br />
<br />
<br />
<br />
[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
<br />
The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
<br />
在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
<br />
<br />
<br />
For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
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<br />
<br />
The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
<br />
The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
<br />
右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
<br />
<br />
<br />
In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
<br />
In water, the critical point occurs at and .<br />
<br />
在水中,临界点发生在 和。<br />
<br />
<br />
<br />
In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
<br />
In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
<br />
在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
<br />
Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
<br />
At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
<br />
在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(临界等温线)中有一个固定的拐点。这意味着在临界点: <br />
<br />
Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
<br />
<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
<br />
左(frac { partial p }{ partial v } right) _ t = 0,<br />
<br />
Elsevier.</ref><br />
<br />
<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
<br />
左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
<br />
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<br />
''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
<br />
The critical isotherm with the critical point&nbsp;K<br />
<br />
临界点 k 的临界等温线<br />
<br />
<br />
<br />
: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
<br />
Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
<br />
在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
<br />
: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
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<br />
<br />
Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
<br />
有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
<br />
<br />
<br />
''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
<br />
Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
<br />
临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
<br />
<br />
<br />
Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
<br />
The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
<br />
<br />
<br />
=== History历史 ===<br />
<br />
[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
<br />
解决上述条件 < math > (partial p/partial v) _ t = 0 </math > 对于范德华方程,可以计算临界点为<br />
<br />
The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
<br />
<math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
8 a }{27Rb } ,<br />
<br />
* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
3nb,<br />
<br />
* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
27b ^ 2} . </math > <br />
<br />
* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
<br />
然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律 <br />
<br />
<br />
<br />
=== Theory理论 ===<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
<br />
为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
<br />
<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
如果你想知道更多的信息,请访问我的网站,<br />
<br />
: <math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
<br />
The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
<br />
对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
<br />
<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
<br />
For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
<br />
对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
<br />
<br />
: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
<center><br />
<br />
< 中心 > <br />
<br />
<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
{ | class = “ wikitable sortable” style = “ text-align: center; ”<br />
<br />
The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
<br />
|-<br />
<br />
|-<br />
<br />
<br />
<br />
! Substance<br />
<br />
!物质<br />
<br />
For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
<br />
! Critical temperature<br />
<br />
!临界温度<br />
<br />
<br />
<br />
! Critical pressure (absolute)<br />
<br />
!临界压力(绝对值)<br />
<br />
=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
<br />
|-<br />
<br />
|-<br />
<br />
{{see also|Critical points of the elements (data page)}}<br />
<br />
| Argon<br />
<br />
| 氩气<br />
<br />
<center><br />
<br />
| }}<br />
<br />
| }}<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
<br />
| Ammonia (NH<sub>3</sub>)<br />
<br />
| 氨(NH < sub > 3 </sub >)<br />
<br />
! Critical temperature<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
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| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0652|{{convert|652|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Mercury (element)|Mercury]]<br />
<br />
| Iron<br />
<br />
铁<br />
<br />
| {{sort|1750.1|{{convert|1476.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|1720|{{convert|1720|atm|kPa|abbr=on}}}}<br />
<br />
|<br />
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|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfur]]<br />
<br />
| Gold<br />
<br />
| 黄金<br />
<br />
| {{sort|1314.00|{{convert|1040.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0207|{{convert|207|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
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|-<br />
<br />
|-<br />
<br />
| [[Iron]]<br />
<br />
| Aluminium<br />
<br />
| 铝<br />
<br />
| {{sort|8500|{{convert|8227|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Gold]]<br />
<br />
| Water (H<sub>2</sub>O)<br />
<br />
| 水(h < sub > 2 </sub > o)<br />
<br />
| {{sort|7250|{{convert|6977|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|5000|{{convert|5000|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
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| }}<br />
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|-<br />
<br />
|- <br />
<br />
|-<br />
<br />
| [[Aluminium]]<br />
<br />
|}<br />
<br />
|}<br />
<br />
| {{sort|7850|{{convert|7577|C|K}}}}<br />
<br />
</center><br />
<br />
</center ><br />
<br />
|<br />
<br />
|-<br />
<br />
| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
<br />
| {{sort|0647.096|{{convert|373.946|C|K}}}}<br />
<br />
A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
<br />
典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
<br />
| {{sort|0217.7|{{convert|217.7|atm|kPa|abbr=on}}}}<br />
<br />
The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
<br />
溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
<br />
|- <br />
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|}<br />
<br />
</center><br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
<br />
从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
<br />
<br />
<br />
[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
<br />
The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
<br />
<br />
===Mathematical definition数学定义===<br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
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<br />
==See also参见==<br />
<br />
<br />
<br />
{{colbegin}}<br />
<br />
* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
{{colend}}<br />
<br />
<br />
<br />
== Footnotes脚注 ==<br />
<br />
{{Reflist|38em}}<br />
<br />
| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
<br />
| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
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<br />
<br />
== References参考 ==<br />
<br />
*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
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<br />
Category:Condensed matter physics<br />
<br />
类别: 凝聚态物理学<br />
<br />
==External links外部链接==<br />
<br />
Category:Conformal field theory<br />
<br />
类别: 共形场论<br />
<br />
* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
<br />
Category:Critical phenomena<br />
<br />
范畴: 关键现象<br />
<br />
*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
<br />
Category:Phase transitions<br />
<br />
类别: 阶段转变<br />
<br />
| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
<br />
Category:Renormalization group<br />
<br />
类别: 重整化群<br />
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<br />
<br />
Category:Threshold temperatures<br />
<br />
类别: 临界温度<br />
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{{Phase_of_matter}}<br />
<br />
Category:Gases<br />
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分类: 气体<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E4%B8%B4%E7%95%8C%E7%82%B9%EF%BC%88%E7%83%AD%E5%8A%9B%E5%AD%A6%EF%BC%89&diff=18767临界点(热力学)2020-11-19T08:08:00Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译<br />
<br />
{{Other uses|Critical point (disambiguation){{!}}Critical point}}<br />
<br />
[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
<br />
[[Image:CriticalPointMeasurementEthane.jpg|thumb|right|upright=1.5|<br />
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[图片: 临界点测量乙烷 jpg | thumb | right | upright = 1.5 | <br />
<br />
{{ordered list<br />
<br />
{{ordered list<br />
<br />
{有序列表<br />
<br />
|Subcritical [[ethane]], liquid and gas phase coexist.<br />
<br />
|Subcritical ethane, liquid and gas phase coexist.<br />
<br />
亚临界乙烷,液态和气态共存。<br />
<br />
|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
<br />
|Critical point (32.17&nbsp;°C, 48.72&nbsp;bar), opalescence.<br />
<br />
| 临界点(32.17 ° c,48.72 bar) ,乳白色。<br />
<br />
|Supercritical [[ethane]], [[fluid]].<ref>{{cite thesis |first=Sven |last=Horstmann |title=Theoretische und experimentelle Untersuchungen zum Hochdruckphasengleichgewichtsverhalten fluider Stoffgemische für die Erweiterung der PSRK-Gruppenbeitragszustandsgleichung |language=de |trans-title=Theoretical and experimental investigations of the high-pressure phase equilibrium behavior of fluid mixtures for the expansion of the [[PSRK]] group contribution equation of state |type=Ph.D. |location=Oldenburg, Germany |publisher=[[University of Oldenburg|Carl-von-Ossietzky Universität Oldenburg]] |year=2000 |isbn=3-8265-7829-5|oclc=76176158}}</ref><br />
<br />
|Supercritical ethane, fluid.<br />
<br />
超临界乙烷,流体。<br />
<br />
}}]]<br />
<br />
}}]]<br />
<br />
}}]]<br />
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<br />
<br />
In [[thermodynamics]], a '''critical point''' (or '''critical state''') is the end point of a phase [[Equilibrium (thermodynamics)|equilibrium]] curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a [[liquid]] and its [[vapor]] can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''<sub>c</sub> and a ''critical pressure'' ''p''<sub>c</sub>, [[phase (matter)|phase]] boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
<br />
In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a critical temperature T<sub>c</sub> and a critical pressure p<sub>c</sub>, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures.<br />
<br />
在热力学中,临界点(或临界状态)是相平衡曲线的终点。最突出的例子是液-汽临界点,即压力-温度曲线的终点,它指明了液体和其蒸汽可以共存的条件。在较高的温度下,气体不能单靠压力液化。在由临界温度Tc和临界压力Pc定义的临界点,相边界消失。其他例子包括混合物中的液-液临界点。 <br />
<br />
<br />
<br />
== Liquid–vapor critical point液-汽临界点 ==<br />
<br />
<br />
<br />
=== Overview 总览===<br />
<br />
<br />
<br />
[[Image:phase-diag2.svg|thumb|upright=1.5|In a typical phase diagram, the boundary between gas and liquid runs from the triple point to the critical point.|The liquid–vapor critical point in a pressure–temperature [[phase diagram]] is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
<br />
The liquid–vapor critical point in a pressure–temperature [[phase diagram is at the high-temperature extreme of the liquid–gas phase boundary. The dotted green line shows the anomalous behavior of water.]]<br />
<br />
在压力-温度[[相图]中,液-汽临界点位于液-气相界面的高温极端处。绿色虚线显示了水的反常行为。]<br />
<br />
<br />
<br />
For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
For simplicity and clarity, the generic notion of critical point is best introduced by discussing a specific example, the liquid–vapor critical point. This was the first critical point to be discovered, and it is still the best known and most studied one.<br />
<br />
为了简单明了,临界点的一般概念最好通过讨论一个具体的例子来介绍,例如液体-蒸汽临界点。这是第一个被发现的临界点,也仍然是最著名和研究最多的一个。<br />
<br />
<br />
<br />
The figure to the right shows the schematic [[PT diagram]] of a ''pure substance'' (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known [[phase (matter)|phases]] ''solid'', ''liquid'' and ''vapor'' are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the [[triple point]], all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some ''critical temperature'' ''T''<sub>c</sub> and ''critical pressure'' ''p''<sub>c</sub>. This is the ''critical point''.<br />
<br />
The figure to the right shows the schematic PT diagram of a pure substance (as opposed to mixtures, which have additional state variables and richer phase diagrams, discussed below). The commonly known phases solid, liquid and vapor are separated by phase boundaries, i.e. pressure–temperature combinations where two phases can coexist. At the triple point, all three phases can coexist. However, the liquid–vapor boundary terminates in an endpoint at some critical temperature T<sub>c</sub> and critical pressure p<sub>c</sub>. This is the critical point.<br />
<br />
右图显示了纯物质的PT示意图(与混合物相反,混合物具有额外的状态变量和更丰富的相图,如下所述)。众所周知的固相、液相和汽相通过相边界分离,即两相可以共存的压力-温度组合。在三相点,所有三个相可以共存。然而,在临界温度Tc和临界压力Pc时,液-汽边界终止于一个端点。这便是临界点。 <br />
<br />
<br />
<br />
In water, the critical point occurs at {{convert|647.096|K|C F}} and {{convert|22.064|MPa|psi atm}}.<ref name=IAPWS95>{{cite journal |last1=Wagner |first1=W. |last2=Pruß |first2=A. |title=The IAPWS Formulation 1995 for the Thermodynamic Properties of Ordinary Water Substance for General and Scientific Use |journal=Journal of Physical and Chemical Reference Data |date=June 2002 |volume=31 |issue=2 |page=398 |doi=10.1063/1.1461829}}</ref><br />
<br />
In water, the critical point occurs at and .<br />
<br />
在水中,临界点发生在 和。<br />
<br />
<br />
<br />
In the ''vicinity'' of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high [[dielectric constant]], and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor [[dielectric]], a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<ref>Anisimov, Sengers, [[Anneke Levelt Sengers|Levelt Sengers]] (2004):<br />
<br />
In the vicinity of the critical point, the physical properties of the liquid and the vapor change dramatically, with both phases becoming ever more similar. For instance, liquid water under normal conditions is nearly incompressible, has a low thermal expansion coefficient, has a high dielectric constant, and is an excellent solvent for electrolytes. Near the critical point, all these properties change into the exact opposite: water becomes compressible, expandable, a poor dielectric, a bad solvent for electrolytes, and prefers to mix with nonpolar gases and organic molecules.<br />
<br />
在临界点附近,液体和蒸汽的物理性质发生了巨大的变化,两个相变得越来越相似。例如,液态水在正常条件下几乎不可压缩,热膨胀系数低,介电常数高,是电解液的优良溶剂。在临界点附近,所有这些性质都会发生完全相反的变化:水变得可压缩、可膨胀、介电性差、电解质溶剂性差,更容易与非极性气体和有机分子混合。 <br />
<br />
Near-critical behavior of aqueous systems.<br />
水体系的近临界行为<br />
Chapter 2 in<br />
<br />
At the critical point, only one phase exists. The heat of vaporization is zero. There is a stationary inflection point in the constant-temperature line (critical isotherm) on a PV diagram. This means that at the critical point:<br />
<br />
在临界点,只有一个相存在。汽化热为零。在PV图上的恒温线(临界等温线)中有一个固定的拐点。这意味着在临界点: <br />
<br />
Aqueous System at Elevated Temperatures and Pressures<br />
高温高压下的水体系 <br />
Palmer et al., eds.<br />
<br />
<math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
<br />
左(frac { partial p }{ partial v } right) _ t = 0,<br />
<br />
Elsevier.</ref><br />
<br />
<math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
<br />
左(frac { partial ^ 2p }{ partial v ^ 2} right) _ t = 0<br />
<br />
<br />
<br />
''At'' the critical point, only one phase exists. The [[heat of vaporization]] is zero. There is a [[stationary point|stationary]] [[inflection point]] in the constant-temperature line (''critical isotherm'') on a [[PV diagram]]. This means that at the critical point:<ref name=Atkins>P. Atkins and J. de Paula, Physical Chemistry, 8th ed. (W. H. Freeman 2006), p. 21.</ref><ref>K. J. Laidler and J. H. Meiser, Physical Chemistry (Benjamin/Cummings 1982), p. 27.</ref><ref>P. A. Rock, Chemical Thermodynamics (MacMillan 1969), p. 123.</ref><br />
<br />
The critical isotherm with the critical point&nbsp;K<br />
<br />
临界点 k 的临界等温线<br />
<br />
<br />
<br />
: <math>\left(\frac{\partial p}{\partial V}\right)_T = 0,</math><br />
<br />
Above the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called supercritical fluid. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by Fisher and Widom, who identified a p–T line that separates states with different asymptotic statistical properties (Fisher–Widom line).<br />
<br />
在临界点以上存在一种物质状态,它与液态和气态连续相连(无相变即可转化)。它被称为超临界流体。关于液体和蒸汽之间的所有区别都在临界点之外消失的共同教科书知识受到了费舍尔和威登的挑战,他们确定了一条p-T线,它将具有不同渐近统计性质的状态分开(Fisher-Widom线)。 <br />
<br />
: <math>\left(\frac{\partial^2p}{\partial V^2}\right)_T = 0.</math><br />
<br />
<br />
<br />
Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is hidden and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a hidden critical point, otherwise we have an exposed critical point.<br />
<br />
有时,临界点并不表现在大多数热力学或机械性质上,而是隐藏在弹性模量的不均匀性开始、非仿射液滴的外观和局部特性的显著变化以及缺陷对浓度的突然增强中。在这些情况下,我们有一个隐藏的临界点,否则说我们有一个暴露的临界点。 <br />
[[Image:Real Gas Isotherms.svg|thumb|upright=1.5|The ''critical isotherm'' with the critical point&nbsp;K]]<br />
<br />
<br />
<br />
''Above'' the critical point there exists a state of matter that is continuously connected with (can be transformed without phase transition into) both the liquid and the gaseous state. It is called [[supercritical fluid]]. The common textbook knowledge that all distinction between liquid and vapor disappears beyond the critical point has been challenged by [[Michael Fisher|Fisher]] and [[Benjamin Widom|Widom]],<ref>Fisher, Widom: ''Decay of Correlations in Linear Systems'', J. Chem. Phys. 50, 3756 (1969).</ref> who identified a ''p''–''T'' line that separates states with different asymptotic statistical properties ([[Fisher–Widom line]]).<br />
<br />
Critical [[carbon dioxide exuding fog while cooling from supercritical to critical temperature.]]<br />
<br />
临界温度[在从超临界温度冷却到临界温度时,二氧化碳释放出雾]<br />
<br />
<br />
<br />
Some times the critical point does not manifest in most thermodynamic or mechanical properties, but is ''hidden'' and reveals itself in the onset of inhomogeneities in elastic moduli, marked changes in the appearance and local properties of non-affine droplets and a sudden enhancement in defect pair concentration. In those cases we have a [[hidden critical point]], otherwise we have an [[exposed critical point]].<ref>{{cite journal |last1=Das |first1=Tamoghna |last2=Ganguly |first2=Saswati |last3=Sengupta |first3=Surajit |last4=Rao |first4=Madan |title=Pre-Yield Non-Affine Fluctuations and A Hidden Critical Point in Strained Crystals |journal=Scientific Reports |date=3 June 2015 |volume=5 |issue=1 |pages=10644 |doi=10.1038/srep10644 |pmid=26039380 |pmc=4454149 |bibcode=2015NatSR...510644D |doi-access=free }}</ref><br />
<br />
The existence of a critical point was first discovered by Charles Cagniard de la Tour in 1822 and named by Dmitri Mendeleev in 1860 and Thomas Andrews in 1869. Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
临界点的存在于1822年由查尔斯 卡尼亚 德拉图尔(Charles Cagniard de la Tour)首次发现,1860年由德米特里·门捷列夫(Dmitri mendelev)和托马斯·安德鲁斯(Thomas Andrews)于1869年分别命名。Cagniard表明,CO2在31°C的压力下可以液化,但在稍高的温度下,即使在高达3000 atm的压力下也不能液化。<br />
<br />
<br />
<br />
=== History历史 ===<br />
<br />
[[Image:Critical carbon dioxide.jpg|thumb|Critical [[carbon dioxide]] exuding [[fog]] while cooling from supercritical to critical temperature.]]<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the van der Waals equation, one can compute the critical point as <br />
<br />
解决上述条件 < math > (partial p/partial v) _ t = 0 </math > 对于范德华方程,可以计算临界点为<br />
<br />
The existence of a critical point was first discovered by [[Charles Cagniard de la Tour]] in 1822<ref>{{cite journal |author=Charles Cagniard de la Tour |date=1822 |url=https://books.google.com/books?id=rzNCAAAAcAAJ&q=Cagniard&pg=PA127 |title=Exposé de quelques résultats obtenu par l'action combinée de la chaleur et de la compression sur certains liquides, tels que l'eau, l'alcool, l'éther sulfurique et l'essence de pétrole rectifiée |trans-title=Presentation of some results obtained by the combined action of heat and compression on certain liquids, such as water, alcohol, sulfuric ether (i.e., diethyl ether), and distilled petroleum spirit |journal=Annales de Chimie et de Physique |volume=21 |pages=127–132 |language=fr}}</ref><ref>Berche, B., Henkel, M., Kenna, R (2009) Critical phenomena: 150 years since Cagniard de la Tour. Journal of Physical Studies 13 (3), pp. 3001-1–3001-4.</ref> and named by [[Dmitri Mendeleev]] in 1860<ref>Mendeleev called the critical point the "absolute temperature of boiling" ({{lang-ru|абсолютная температура кипения}}; {{lang-de|absolute Siedetemperatur}}).<br />
<br />
<math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
8 a }{27Rb } ,<br />
<br />
* {{cite journal |last1=Менделеев |first1=Д. |title=О расширении жидкостей от нагревания выше температуры кипения |journal=Горный Журнал [Mining Journal] |date=1861 |volume=4 |pages=141–152 |trans-title=On the expansion of liquids from heating above the temperature of boiling |language=ru}} The "absolute temperature of boiling" is defined on p. 151. Available at [https://upload.wikimedia.org/wikipedia/commons/e/e6/%D0%93%D0%BE%D1%80%D0%BD%D1%8B%D0%B9_%D0%B6%D1%83%D1%80%D0%BD%D0%B0%D0%BB%2C_1861%2C_%E2%84%9604_%28%D0%B0%D0%BF%D1%80%D0%B5%D0%BB%D1%8C%29.pdf Wikimedia]<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
3nb,<br />
<br />
* German translation: {{cite journal |last1=Mendelejeff |first1=D. |title=Ueber die Ausdehnung der Flüssigkeiten beim Erwärmen über ihren Siedepunkt |journal=Annalen der Chemie und Pharmacie |date=1861 |volume=119 |pages=1–11 |url=https://babel.hathitrust.org/cgi/pt?id=uc1.c036497486;view=1up;seq=13 |trans-title=On the expansion of fluids during heating above their boiling point |language=de |doi=10.1002/jlac.18611190102 }} The "absolute temperature of boiling" is defined on p. 11: "{{lang|de|2=Als absolute Siedetemperatur müssen wir den Punkt betrachten, bei welchem 1) die Cohäsion der Flüssigkeit = 0° ist und a<sup>2</sup> = 0, bei welcher 2) die latente Verdamfungswärme auch = 0 ist und bei welcher sich 3) die Flüssigkeit in Dampf verwandelt, unabhängig von Druck und Volum."}} (As the "absolute temperature of boiling" we must regard the point at which (1) the cohesion of the liquid equals 0° and ''a''<sup>2</sup> = 0 [where ''a''<sup>2</sup> is the coefficient of capillarity, p. 6], at which (2) the latent heat of vaporization also equals zero, and at which (3) the liquid is transformed into vapor, independently of the pressure and the volume.)<br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
27b ^ 2} . </math > <br />
<br />
* In 1870, Mendeleev asserted, against Thomas Andrews, his priority regarding the definition of the critical point: {{cite journal |last1=Mendelejeff |first1=D. |title=Bemerkungen zu den Untersuchungen von Andrews über die Compressibilität der Kohlensäure |journal=Annalen der Physik |date=1870 |volume=141 |pages=618–626 |url=https://babel.hathitrust.org/cgi/pt?id=wu.89048352249;view=1up;seq=648 |series=2nd series |trans-title=Comments on Andrews' investigations into the compressibility of carbon dioxide |language=de}}</ref><ref>Landau, Lifshitz, Theoretical Physics, Vol. V: Statistical Physics, Ch. 83 [German edition 1984].</ref> and [[Thomas Andrews (scientist)|Thomas Andrews]] in 1869.<ref>{{cite journal |author=Andrews, Thomas |date=1869 |url=http://rstl.royalsocietypublishing.org/content/159/575.full.pdf+html |title=The Bakerian lecture: On the continuity of the gaseous and liquid states of matter |journal=Philosophical Transactions of the Royal Society |location=London |volume=159 |pages=575–590 |doi=10.1098/rstl.1869.0021 |doi-access=free }} The term "critical point" appears on page 588.</ref> Cagniard showed that CO<sub>2</sub> could be liquefied at 31&nbsp;°C at a pressure of 73&nbsp;atm, but not at a slightly higher temperature, even under pressures as high as 3000&nbsp;atm.<br />
<br />
However, the van der Waals equation, based on a mean-field theory, does not hold near the critical point. In particular, it predicts wrong scaling laws.<br />
<br />
然而,基于平均场理论的van der Waals方程在临界点附近并不成立。尤其是,它预测了错误的标度定律 <br />
<br />
<br />
<br />
=== Theory理论 ===<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<br />
<br />
为了分析临界点附近的流体性质,有时需要定义相对于临界性质的简化状态变量<br />
<br />
<br />
<br />
Solving the above condition <math>(\partial p / \partial V)_T = 0</math> for the [[van der Waals equation]], one can compute the critical point as <br />
<br />
<math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
如果你想知道更多的信息,请访问我的网站,<br />
<br />
: <math>T_\text{c} = \frac{8a}{27Rb},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
4.1.1.1.2.2.2.2.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3<br />
<br />
\quad V_\text{c} = 3nb,<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
4 v _ text { r } = frac { v }{ RT _ text { c }/p _ text { c } . </math > <br />
<br />
\quad p_\text{c} = \frac{a}{27b^2}.</math><br />
<br />
However, the van der Waals equation, based on a [[mean-field theory]], does not hold near the critical point. In particular, it predicts wrong [[scaling law]]s.<br />
<br />
The principle of corresponding states indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of p<sub>r</sub>.<br />
<br />
对应态原理表明,在相同的减压和温度下,物质具有相等的还原体积。这种关系对于许多物质来说几乎是正确的,但是对于pr的大值,这种关系变得越来越不准确。<br />
<br />
<br />
<br />
To analyse properties of fluids near the critical point, reduced state variables are sometimes defined relative to the critical properties<ref>{{Cite book | last1 = Cengel | first1 = Yunus A. | last2 = Boles | first2 = Michael A. | title = Thermodynamics: an engineering approach | year = 2002 | publisher = McGraw-Hill | location = Boston | isbn = 978-0-07-121688-3 | pages = 91–93}}</ref><br />
<br />
For some gases, there is an additional correction factor, called Newton's correction, added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<br />
<br />
对于某些气体,在以这种方式计算的临界温度和临界压力上,还有一个额外的修正系数,叫做牛顿修正。这些是根据经验得出的值,并随感兴趣的压力范围而变化。<br />
<br />
<br />
: <math>T_\text{r} = \frac{T}{T_\text{c}},<br />
<br />
\quad p_\text{r} = \frac{p}{p_\text{c}},<br />
<br />
\quad V_\text{r} = \frac{V}{RT_\text{c} / p_\text{c}}.</math><br />
<br />
<center><br />
<br />
< 中心 > <br />
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<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
<br />
{ | class = “ wikitable sortable” style = “ text-align: center; ”<br />
<br />
The [[theorem of corresponding states|principle of corresponding states]] indicates that substances at equal reduced pressures and temperatures have equal reduced volumes. This relationship is approximately true for many substances, but becomes increasingly inaccurate for large values of ''p''<sub>r</sub>.<br />
<br />
|-<br />
<br />
|-<br />
<br />
<br />
<br />
! Substance<br />
<br />
!物质<br />
<br />
For some gases, there is an additional correction factor, called ''Newton's correction'', added to the critical temperature and critical pressure calculated in this manner. These are empirically derived values and vary with the pressure range of interest.<ref>{{cite journal |title= Compressibility Chart for Hydrogen and Inert Gases |first1= Frank D. |last1= Maslan |first2= Theodore M. |last2= Littman |journal= Ind. Eng. Chem. |year= 1953 |volume= 45 |issue= 7 |pages= 1566–1568 |doi= 10.1021/ie50523a054 }}</ref><br />
<br />
! Critical temperature<br />
<br />
!临界温度<br />
<br />
<br />
<br />
! Critical pressure (absolute)<br />
<br />
!临界压力(绝对值)<br />
<br />
=== Table of liquid–vapor critical temperature and pressure for selected substances ===<br />
<br />
|-<br />
<br />
|-<br />
<br />
{{see also|Critical points of the elements (data page)}}<br />
<br />
| Argon<br />
<br />
| 氩气<br />
<br />
<center><br />
<br />
| }}<br />
<br />
| }}<br />
<br />
{| class="wikitable sortable" style="text-align: center;"<br />
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| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
! Substance<ref>{{cite book |last= Emsley |first= John |title= The Elements |edition= Second |publisher= [[Oxford University Press]] |year= 1991 |isbn= 978-0-19-855818-7 }}</ref><ref>{{cite book |first1= Yunus A. |last1= Cengel |first2= Michael A. |last2= Boles |title= Thermodynamics: An Engineering Approach |pages= [https://archive.org/details/thermodynamicsen00ceng_0/page/824 824] |edition= Fourth |publisher= [[McGraw-Hill]] |year= 2002 |isbn= 978-0-07-238332-4 |url-access= registration |url= https://archive.org/details/thermodynamicsen00ceng_0/page/824 }}</ref><br />
<br />
| Ammonia (NH<sub>3</sub>)<br />
<br />
| 氨(NH < sub > 3 </sub >)<br />
<br />
! Critical temperature<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
! Critical pressure (absolute)<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Argon]]<br />
<br />
| {{sort|0150.8|{{convert|-122.4|C|K}}}}<br />
<br />
| R-134a <br />
<br />
| R-134a<br />
<br />
| {{sort|0048.1|{{convert|48.1|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[Ammonia]] (NH<sub>3</sub>)<ref>{{Cite web|url=http://www.engineeringtoolbox.com/ammonia-d_971.html|title=Ammonia - NH3 - Thermodynamic Properties|website=www.engineeringtoolbox.com|access-date=2017-04-07}}</ref><br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0405.6|{{convert|132.4|C|K}}}}<br />
<br />
| {{sort|0111.3|{{convert|111.3|atm|kPa|abbr=on}}}}<br />
<br />
| R-410A <br />
<br />
| R-410A<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-134a]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0374|{{convert|101.06|C|K}}}}<br />
<br />
| {{sort|0040|{{convert|40.06|atm|kPa|abbr=on}}}}<br />
<br />
| Bromine<br />
<br />
| 溴<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| [[R-410A]] <br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{sort|0346|{{convert|72.8|C|K}}}}<br />
<br />
| Caesium<br />
<br />
铯<br />
<br />
| {{sort|0047|{{convert|47.08|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Bromine]]<br />
<br />
| Chlorine<br />
<br />
| 氯气<br />
<br />
| {{sort|0584.0|{{convert|310.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0102|{{convert|102|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Caesium]]<br />
<br />
| Ethanol (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| 乙醇(c < sub > 2 </sub > h < sub > 5 </sub > OH)<br />
<br />
| {{sort|1938.00|{{convert|1664.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0094|{{convert|94|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Chlorine]]<br />
<br />
| Fluorine<br />
<br />
| 氟<br />
<br />
| {{sort|0417.0|{{convert|143.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0076.0|{{convert|76.0|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Ethanol]] (C<sub>2</sub>H<sub>5</sub>OH)<br />
<br />
| Helium<br />
<br />
| 氦气<br />
<br />
| {{sort|0514.0|{{convert|241|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0062.2|{{convert|62.18|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Fluorine]]<br />
<br />
| Hydrogen<br />
<br />
| 氢气<br />
<br />
| {{sort|0144.30|{{convert|-128.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0051.5|{{convert|51.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Helium]]<br />
<br />
| Krypton<br />
<br />
氪星<br />
<br />
| {{sort|0005.19|{{convert|-267.96|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0002.24|{{convert|2.24|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Hydrogen]]<br />
<br />
| Methane (CH<sub>4</sub>)<br />
<br />
| 甲烷(CH < sub > 4 </sub >)<br />
<br />
| {{sort|0033.20|{{convert|-239.95|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0012.8|{{convert|12.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Krypton]]<br />
<br />
| Neon<br />
<br />
霓虹灯<br />
<br />
| {{sort|0209.4|{{convert|-63.8|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0054.3|{{convert|54.3|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Methane]] (CH<sub>4</sub>)<br />
<br />
| Nitrogen<br />
<br />
| 氮气<br />
<br />
| {{sort|0190.8|{{convert|-82.3|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.79|{{convert|45.79|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Neon]]<br />
<br />
| Oxygen (O<sub>2</sub>)<br />
<br />
| 氧气(o < sub > 2 </sub >)<br />
<br />
| {{sort|0044.40|{{convert|-228.75|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0027.2|{{convert|27.2|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrogen]]<br />
<br />
| Carbon dioxide (CO<sub>2</sub>)<br />
<br />
| 二氧化碳(CO < sub > 2 </sub >)<br />
<br />
| {{sort|0126.3|{{convert|-146.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0033.5|{{convert|33.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Oxygen]] (O<sub>2</sub>)<br />
<br />
| Nitrous oxide (N<sub>2</sub>O)<br />
<br />
| 氧化亚氮(n < sub > 2 </sub > o)<br />
<br />
| {{sort|0154.6|{{convert|-118.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0049.8|{{convert|49.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Carbon dioxide]] (CO<sub>2</sub>)<br />
<br />
| Sulfuric acid (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| 硫酸(h < sub > 2 </sub > SO < sub > 4 </sub >)<br />
<br />
| {{sort|0304.19|{{convert|31.04|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|72.8|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Nitrous oxide]] (N<sub>2</sub>O)<br />
<br />
| Xenon<br />
<br />
| 氙气<br />
<br />
| {{sort|0304.19|{{convert|36.4|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0072.8|{{convert|71.5|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfuric acid]] (H<sub>2</sub>SO<sub>4</sub>)<br />
<br />
| Lithium<br />
<br />
| Lithium<br />
<br />
| {{sort|0927|{{convert|654|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0045.4|{{convert|45.4|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Xenon]]<br />
<br />
| Mercury<br />
<br />
水星<br />
<br />
| {{sort|0289.8|{{convert|16.6|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0057.6|{{convert|57.6|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Lithium]]<br />
<br />
| Sulfur<br />
<br />
硫磺<br />
<br />
| {{sort|3223|{{convert|2950|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0652|{{convert|652|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Mercury (element)|Mercury]]<br />
<br />
| Iron<br />
<br />
铁<br />
<br />
| {{sort|1750.1|{{convert|1476.9|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|1720|{{convert|1720|atm|kPa|abbr=on}}}}<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Sulfur]]<br />
<br />
| Gold<br />
<br />
| 黄金<br />
<br />
| {{sort|1314.00|{{convert|1040.85|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|0207|{{convert|207|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Iron]]<br />
<br />
| Aluminium<br />
<br />
| 铝<br />
<br />
| {{sort|8500|{{convert|8227|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|<br />
<br />
|<br />
<br />
|<br />
<br />
|-<br />
<br />
|-<br />
<br />
|-<br />
<br />
| [[Gold]]<br />
<br />
| Water (H<sub>2</sub>O)<br />
<br />
| 水(h < sub > 2 </sub > o)<br />
<br />
| {{sort|7250|{{convert|6977|C|K}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
| {{sort|5000|{{convert|5000|atm|kPa|abbr=on}}}}<br />
<br />
| }}<br />
<br />
| }}<br />
<br />
|-<br />
<br />
|- <br />
<br />
|-<br />
<br />
| [[Aluminium]]<br />
<br />
|}<br />
<br />
|}<br />
<br />
| {{sort|7850|{{convert|7577|C|K}}}}<br />
<br />
</center><br />
<br />
</center ><br />
<br />
|<br />
<br />
|-<br />
<br />
| [[Water]] (H<sub>2</sub>O)<ref name=IAPWS95/><ref>{{cite web | title = Critical Temperature and Pressure | publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-19 }}</ref><br />
<br />
| {{sort|0647.096|{{convert|373.946|C|K}}}}<br />
<br />
A plot of typical polymer solution phase behavior including two critical points: a [[LCST and an UCST]]<br />
<br />
典型的聚合物溶液相行为图,包括两个临界点: a [ LCST 和 UCST ]<br />
<br />
| {{sort|0217.7|{{convert|217.7|atm|kPa|abbr=on}}}}<br />
<br />
The liquid–liquid critical point of a solution, which occurs at the critical solution temperature, occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the upper critical solution temperature (UCST), which is the hottest point at which cooling induces phase separation, and the lower critical solution temperature (LCST), which is the coldest point at which heating induces phase separation.<br />
<br />
溶液的液-液临界点出现在临界溶液温度下,出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是上临界溶液温度(UCST),这是冷却导致相分离的最热点,而下临界溶液温度(LCST)是加热导致相分离的最冷点。<br />
<br />
|- <br />
<br />
|}<br />
<br />
</center><br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the spinodal curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the second derivative of the free energy with respect to concentration must equal zero), and the extremum condition (the third derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
<br />
从理论上讲,液-液临界点代表旋节曲线的温度-浓度极值(如右图所示)。因此,双组分体系的液-液临界点必须满足两个条件:旋节曲线的条件(自由能对浓度的二阶导数必须等于零),以及极值条件(自由能对浓度的三阶导数也必须等于零,或者旋节温度对浓度的导数必须等于零)<br />
==Mixtures: liquid–liquid critical point混合物:液体-液体临界点 ==<br />
<br />
<br />
<br />
[[Image:LCST-UCST plot.svg|thumb|upright=1.5|A plot of typical polymer solution phase behavior including two critical points: a [[LCST]] and an [[Upper critical solution temperature|UCST]]]]<br />
<br />
The [[liquid–liquid critical point]] of a solution, which occurs at the ''critical solution temperature'', occurs at the limit of the two-phase region of the phase diagram. In other words, it is the point at which an infinitesimal change in some thermodynamic variable (such as temperature or pressure) leads to separation of the mixture into two distinct liquid phases, as shown in the polymer–solvent phase diagram to the right. Two types of liquid–liquid critical points are the [[upper critical solution temperature]] (UCST), which is the hottest point at which cooling induces phase separation, and the [[lower critical solution temperature]] (LCST), which is the coldest point at which heating induces phase separation.<br />
在“临界溶液温度”下,溶液的[[液-液临界点]]出现在相图两相区的极限处。换言之,它是某个热力学变量(如温度或压力)的微小变化导致混合物分离为两个不同的液相的点,如右侧的聚合物-溶剂相图所示。两种类型的液-液临界点是[[上临界溶液温度]](UCST),这是冷却导致相分离的最热点,和[[下临界溶液温度]](LCST),这是加热导致相分离的最冷点。 <br />
<br />
<br />
===Mathematical definition数学定义===<br />
<br />
<br />
<br />
From a theoretical standpoint, the liquid–liquid critical point represents the temperature–concentration extremum of the [[spinodal]] curve (as can be seen in the figure to the right). Thus, the liquid–liquid critical point in a two-component system must satisfy two conditions: the condition of the spinodal curve (the ''second'' derivative of the [[Gibbs free energy|free energy]] with respect to concentration must equal zero), and the extremum condition (the ''third'' derivative of the free energy with respect to concentration must also equal zero or the derivative of the spinodal temperature with respect to concentration must equal zero).<br />
从理论上看,从液体的临界点(从理论上看,是指液体的临界温度)。因此,双组分体系中的液-液临界点必须满足两个条件:旋节曲线的条件([[Gibbs自由能|自由能]]相对于浓度的“二阶”导数必须等于零)和极值条件(自由能相对于浓度的“第三”导数)也必须等于零,或者旋节温度对浓度的导数必须等于零)。<br />
<br />
<br />
==See also参见==<br />
<br />
<br />
<br />
{{colbegin}}<br />
<br />
* [[Conformal field theory]]<br />
共形场论<br />
* [[Critical exponents]]<br />
临界指数<br />
* [[Critical phenomena]] (more advanced article)<br />
临界现象<br />
* [[Critical points of the elements (data page)]]<br />
要素临界点<br />
* [[Curie point]]<br />
居里点<br />
* [[Joback method]], [[Klincewicz method]], [[Lydersen method]] (estimation of critical temperature, pressure, and volume from molecular structure)<br />
Joback 方法 Klingewicz方法 Lydersen 方法(从分子结构估算临界温度、压力和体积)<br />
* [[Liquid–liquid critical point]]<br />
液体-液体临界点<br />
* [[Lower critical solution temperature]]<br />
较低临界溶液温度<br />
* [[Néel point]]<br />
Néel点<br />
* [[Percolation thresholds]]<br />
过滤阈值<br />
* [[Phase transition]]<br />
相变<br />
* [[Rushbrooke inequality]]<br />
Rushbrooke不等式<br />
* [[Scale invariance]]<br />
比例不变性<br />
* [[Self-organized criticality]]<br />
自组织临界性<br />
* [[Supercritical fluid]], [[Supercritical drying]], [[Supercritical water oxidation]], [[Supercritical fluid extraction]]<br />
超临界流体 超临界干燥 超临界水氧化 超临界流体萃取 <br />
* [[Tricritical point]]<br />
三临界点<br />
* [[Triple point]]<br />
三重点<br />
* [[Upper critical solution temperature]]<br />
上临界溶液温度<br />
* [[Widom scaling]]<br />
Widom缩放<br />
{{colend}}<br />
<br />
<br />
<br />
== Footnotes脚注 ==<br />
<br />
{{Reflist|38em}}<br />
<br />
| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
<br />
| publisher = 普渡大学 | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03}<br />
<br />
<br />
<br />
== References参考 ==<br />
<br />
*{{cite web | title = Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam | publisher = International Association for the Properties of Water and Steam | date = August 2007 | url = http://www.iapws.org/relguide/IF97-Rev.pdf | accessdate = 2009-06-09 }}<br />
<br />
<br />
<br />
Category:Condensed matter physics<br />
<br />
类别: 凝聚态物理学<br />
<br />
==External links==<br />
<br />
Category:Conformal field theory<br />
<br />
类别: 共形场论<br />
<br />
* {{cite web |title=Critical points for some common solvents |url=http://www.proscitech.com.au/catalogue/notes/cpd.htm |archiveurl=https://web.archive.org/web/20080131081956/http://www.proscitech.com.au/catalogue/notes/cpd.htm |publisher=ProSciTech |archivedate=2008-01-31}}<br />
<br />
Category:Critical phenomena<br />
<br />
范畴: 关键现象<br />
<br />
*{{cite web | title = Critical Temperature and Pressure | work = Department of Chemistry<br />
<br />
Category:Phase transitions<br />
<br />
类别: 阶段转变<br />
<br />
| publisher = Purdue University | url = http://www.chem.purdue.edu/gchelp/liquids/critical.html | accessdate = 2006-12-03 }}<br />
<br />
Category:Renormalization group<br />
<br />
类别: 重整化群<br />
<br />
<br />
<br />
Category:Threshold temperatures<br />
<br />
类别: 临界温度<br />
<br />
{{Phase_of_matter}}<br />
<br />
Category:Gases<br />
<br />
分类: 气体<br />
<br />
<noinclude><br />
<br />
<small>This page was moved from [[wikipedia:en:Critical point (thermodynamics)]]. Its edit history can be viewed at [[临界点(热力学)/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%B1%B3%E5%8B%92-%E5%B0%A4%E9%87%8C%E5%AE%9E%E9%AA%8C&diff=18467米勒-尤里实验2020-11-16T09:32:39Z<p>Henry:</p>
<hr />
<div>此词条暂由Henry翻译。<br />
<br />
{{short description|Chemical experiment that simulated conditions on the early Earth and tested the origin of life}}<br />
<br />
[[File:MUexperiment.png|thumb|upright=1.5|The experiment]]<br />
<br />
The experiment<br />
<br />
实验<br />
<br />
<br />
<br />
The '''Miller–Urey experiment'''<ref>{{cite journal |vauthors=Hill HG, Nuth JA |title=The catalytic potential of cosmic dust: implications for prebiotic chemistry in the solar nebula and other protoplanetary systems |journal=Astrobiology |volume=3 |issue=2 |pages=291–304 |year=2003 |pmid=14577878 |doi=10.1089/153110703769016389|bibcode = 2003AsBio...3..291H}}</ref> (or '''Miller experiment''')<ref>{{cite journal | title=The analysis of comet mass spectrometric data |author1=Balm SP |author2=Hare J.P. |author3=Kroto HW | journal=Space Science Reviews| year=1991| volume=56|issue=1–2 | pages=185–9 |doi=10.1007/BF00178408 | bibcode=1991SSRv...56..185B|url=https://www.semanticscholar.org/paper/9bce3627fcb31bac372e6610472e59008703ec4b }}</ref> was a chemical [[experiment]] that simulated the conditions thought at the time (1952) to be present on the [[early Earth]] and tested the [[abiogenesis|chemical origin of life]] under those conditions. The experiment at the time supported [[Alexander Oparin]]'s and [[J. B. S. Haldane]]'s hypothesis that putative conditions on the primitive Earth favoured chemical reactions that synthesized more complex [[organic compound]]s from simpler inorganic precursors. Considered to be the classic experiment investigating [[abiogenesis]], it was performed in 1952 by [[Stanley Miller]], supervised by [[Harold Urey]] at the [[University of Chicago]], and published the following year.<ref name=miller1953>{{cite journal |last=Miller |first=Stanley L. |url=http://www.abenteuer-universum.de/pdf/miller_1953.pdf |title=Production of Amino Acids Under Possible Primitive Earth Conditions |journal=[[Science (journal)|Science]] |year=1953 |volume=117 |pages=528–9 |doi=10.1126/science.117.3046.528 |pmid=13056598 |issue=3046 |bibcode=1953Sci...117..528M |url-status=dead |archiveurl=https://web.archive.org/web/20120317062622/http://www.abenteuer-universum.de/pdf/miller_1953.pdf |archivedate=2012-03-17 |access-date=2011-01-17 }}</ref><ref>{{cite journal |last=Miller |first=Stanley L. |author2=Harold C. Urey |title=Organic Compound Synthesis on the Primitive Earth |journal=[[Science (journal)|Science]] |year=1959 |volume=130 |pages=245–51 |doi=10.1126/science.130.3370.245 |pmid=13668555 |issue=3370|bibcode = 1959Sci...130..245M}} Miller states that he made "A more complete analysis of the products" in the 1953 experiment, listing additional results.</ref><ref>{{cite journal |title=The 1953 Stanley L. Miller Experiment: Fifty Years of Prebiotic Organic Chemistry |author1=A. Lazcano |author2=J. L. Bada |journal=Origins of Life and Evolution of Biospheres |volume=33 |year=2004 |pages=235–242 |doi=10.1023/A:1024807125069 |pmid=14515862 |issue=3|url=https://www.semanticscholar.org/paper/beda7cb912470cec6e1bf2d13535edeedf6c5b16 |bibcode=2003OLEB...33..235L }}</ref><br />
<br />
The Miller–Urey experiment (or Miller experiment) was a chemical experiment that simulated the conditions thought at the time (1952) to be present on the early Earth and tested the chemical origin of life under those conditions. The experiment at the time supported Alexander Oparin's and J. B. S. Haldane's hypothesis that putative conditions on the primitive Earth favoured chemical reactions that synthesized more complex organic compounds from simpler inorganic precursors. Considered to be the classic experiment investigating abiogenesis, it was performed in 1952 by Stanley Miller, supervised by Harold Urey at the University of Chicago, and published the following year.<br />
<br />
<font color="#ff8000"> 米勒尤里实验 Miller–Urey experiment</font>(或称 Miller 实验)是一个化学实验,模拟了当时(1952年)认为存在于早期地球上的条件,并在这些条件下测试了生命的化学起源。当时的实验支持了亚历山大·奥帕林和J·B·s·霍尔丹的假设,即原始地球上假定的条件有利于化学反应,即从简单的无机前体合成更复杂的有机化合物。它被认为是研究自然发生的经典实验,1952年由斯坦利·米勒完成,由芝加哥大学的哈罗德·尤里监督,并于次年出版。<br />
<br />
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After Miller's death in 2007, scientists examining sealed vials preserved from the original experiments were able to show that there were actually well over 20 different [[amino acid]]s produced in Miller's original experiments. That is considerably more than what Miller originally reported, and more than the 20 that naturally occur in the genetic code.<ref name="BBC"/> More recent evidence suggests that Earth's original atmosphere might have had a composition different from the gas used in the Miller experiment, but prebiotic experiments continue to produce [[racemic mixture]]s of simple-to-complex compounds under varying conditions.<ref name=bada2013>{{cite journal|last1=Bada|first1=Jeffrey L.|title=New insights into prebiotic chemistry from Stanley Miller's spark discharge experiments|journal=Chemical Society Reviews|year=2013|volume=42|issue=5|pages=2186–96|doi=10.1039/c3cs35433d|pmid=23340907|url=https://semanticscholar.org/paper/6f463e8a3611fa7f25c143991dfddac49c396b73}}</ref><br />
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After Miller's death in 2007, scientists examining sealed vials preserved from the original experiments were able to show that there were actually well over 20 different amino acids produced in Miller's original experiments. That is considerably more than what Miller originally reported, and more than the 20 that naturally occur in the genetic code.<br />
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2007年米勒去世后,科学家们检查了从原始实验中保存下来的密封小瓶,发现实际上米勒原始实验中产生了超过20种不同的氨基酸。这大大超过了米勒最初报道的数量,也超过了遗传密码中自然产生的20种。<br />
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== Experiment实验 ==<br />
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[[File:Miller-Urey experiment - Work by the C3BC consortium, licensed under CC-BY-3.0.webm|thumb|Descriptive video of the experiment]]<br />
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Descriptive video of the experiment<br />
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实验的描述性视频<br />
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The experiment used [[water]] (H<sub>2</sub>O), [[methane]] (CH<sub>4</sub>), [[ammonia]] (NH<sub>3</sub>), and [[hydrogen]] (H<sub>2</sub>). The chemicals were all sealed inside a sterile 5-liter glass flask connected to a 500 ml flask half-full of water. The water in the smaller flask was heated to induce [[evaporation]], and the water vapour was allowed to enter the larger flask. Continuous electrical sparks were fired between the electrodes to simulate [[lightning]] in the water vapour and gaseous mixture, and then the simulated atmosphere was cooled again so that the water condensed and trickled into a U-shaped trap at the bottom of the apparatus.<br />
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The experiment used water (H<sub>2</sub>O), methane (CH<sub>4</sub>), ammonia (NH<sub>3</sub>), and hydrogen (H<sub>2</sub>). The chemicals were all sealed inside a sterile 5-liter glass flask connected to a 500 ml flask half-full of water. The water in the smaller flask was heated to induce evaporation, and the water vapour was allowed to enter the larger flask. Continuous electrical sparks were fired between the electrodes to simulate lightning in the water vapour and gaseous mixture, and then the simulated atmosphere was cooled again so that the water condensed and trickled into a U-shaped trap at the bottom of the apparatus.<br />
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实验用水(H2O)、甲烷(CH4)、氨(NH3)和氢(H 2)。所有的化学物质都被密封在一个5升的无菌玻璃瓶里,这个玻璃瓶连接着一个500毫升的半满水的烧瓶。将小烧瓶中的水加热以诱导蒸发,使水蒸气进入大烧瓶。在电极之间连续地点燃电火花,以模拟水蒸气和气体混合物中的闪电,然后再次冷却模拟的大气,使水凝结并滴入装置底部的U形阱中。<br />
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After a day, the solution collected at the trap had turned pink in colour, and after a week of continuous operation the solution was deep red and turbid.<ref name=miller1953/> The boiling flask was then removed, and mercuric chloride was added to prevent microbial contamination. The reaction was stopped by adding barium hydroxide and sulfuric acid, and evaporated to remove impurities. Using [[paper chromatography]], Miller identified five amino acids present in the solution: [[glycine]], [[alanine|α-alanine]] and [[beta-Alanine|β-alanine]] were positively identified, while [[aspartic acid]] and [[alpha-Aminobutyric acid|α-aminobutyric acid]] (AABA) were less certain, due to the spots being faint.<ref name=miller1953/><br />
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After a day, the solution collected at the trap had turned pink in colour, and after a week of continuous operation the solution was deep red and turbid.<br />
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一天之后,在诱捕器上收集到的溶液变成了粉红色,连续操作一周之后,溶液变成了深红色和混浊的液体。<br />
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In a 1996 interview, Stanley Miller recollected his lifelong experiments following his original work and stated: "Just turning on the spark in a basic pre-biotic experiment will yield 11 out of 20 amino acids."<ref>{{cite web|url=http://www.accessexcellence.org/WN/NM/miller.php |title=Exobiology: An Interview with Stanley L. Miller |publisher=Accessexcellence.org |archiveurl=https://web.archive.org/web/20080518054852/http://www.accessexcellence.org/WN/NM/miller.php |archivedate=May 18, 2008 |accessdate=2009-08-20}}</ref><br />
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The original experiment remained in 2017 under the care of Miller and Urey's former student Jeffrey Bada, a professor at the UCSD, Scripps Institution of Oceanography. , the apparatus used to conduct the experiment was on display at the Denver Museum of Nature and Science.<br />
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最初的实验在2017年由 Miller 和 Urey以前的学生 Jeffrey Bada 负责,他是加州大学圣地亚哥分校斯克里普斯海洋研究所的教授。实验仪器在丹佛自然科学博物馆展出。<br />
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The original experiment remained in 2017 under the care of Miller and Urey's former student [[Jeffrey Bada]], a professor at the [[University of California, San Diego|UCSD]], [[Scripps Institution of Oceanography]].<ref>{{cite news |url=https://www.nytimes.com/2010/05/18/science/18conv.html |title=A Conversation With Jeffrey L. Bada: A Marine Chemist Studies How Life Began |newspaper=nytimes.com |date=2010-05-17 |first=Claudia |last=Dreifus |authorlink=Claudia Dreifus |url-status=live |archiveurl=https://web.archive.org/web/20170118034218/http://www.nytimes.com/2010/05/18/science/18conv.html |archivedate=2017-01-18 }}</ref> {{asof|2013}}, the apparatus used to conduct the experiment was on display at the [[Denver Museum of Nature and Science]].<ref>{{cite news|url=http://www.dmns.org/science/museum-scientists/david-grinspoon/funky-science-wonder-lab/research-updates/astrobiology-collection-miller-urey-apparatus | title=Astrobiology Collection: Miller-Urey Apparatus |archiveurl=https://web.archive.org/web/20130524090309/http://www.dmns.org/science/museum-scientists/david-grinspoon/funky-science-wonder-lab/research-updates/astrobiology-collection-miller-urey-apparatus/ |archivedate=2013-05-24 |publisher=Denver Museum of Nature & Science }}</ref>{{update after|2020|4|14}}<br />
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One-step reactions among the mixture components can produce hydrogen cyanide (HCN), formaldehyde (CH<sub>2</sub>O), and other active intermediate compounds (acetylene, cyanoacetylene, etc.):<br />
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混合组分之间的一步反应可以生成氰化氢、甲醛和其他活性中间体化合物(乙炔、氰乙炔等):<br />
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==Chemistry of experiment实验化学==<br />
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One-step reactions among the mixture components can produce [[hydrogen cyanide]] (HCN), [[formaldehyde]] (CH<sub>2</sub>O),<ref>https://www.webcitation.org/query?url=http://www.geocities.com/capecanaveral/lab/2948/orgel.html&date=2009-10-25+16:53:26 Origin of Life on Earth by Leslie E. Orgel</ref><ref>{{Cite book |url=http://books.nap.edu/openbook.php?record_id=11860&page=85 |title=Read "Exploring Organic Environments in the Solar System" at NAP.edu |accessdate=2008-10-25 |url-status=live |archiveurl=https://web.archive.org/web/20090621053626/http://books.nap.edu/openbook.php?record_id=11860&page=85 |archivedate=2009-06-21 |doi=10.17226/11860 |year=2007 |isbn=978-0-309-10235-3 |last1=Council |first1=National Research |last2=Studies |first2=Division on Earth Life |last3=Technology |first3=Board on Chemical Sciences and |last4=Sciences |first4=Division on Engineering Physical |last5=Board |first5=Space Studies |last6=System |first6=Task Group on Organic Environments in the Solar }} Exploring Organic Environments in the Solar System (2007)</ref> and other active intermediate compounds ([[acetylene]], [[cyanoacetylene]], etc.):{{Citation needed|date=June 2016}}<br />
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CO<sub>2</sub> &rarr; CO + [O] (atomic oxygen)<br />
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CO < sub > 2 </sub > & rarr; CO + [ o ](原子氧) <br />
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CH<sub>4</sub> + 2[O] &rarr; CH<sub>2</sub>O + H<sub>2</sub>O<br />
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CH < sub > 4 </sub > + 2[ o ] & rarr; CH < sub > 2 </sub > o + h < sub > 2 </sub > o<br />
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: CO<sub>2</sub> &rarr; CO + [O] (atomic oxygen)<br />
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CO + NH<sub>3</sub> &rarr; HCN + H<sub>2</sub>O<br />
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CO + NH < sub > 3 </sub > & rarr; HCN + h < sub > 2 </sub > o<br />
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: CH<sub>4</sub> + 2[O] &rarr; CH<sub>2</sub>O + H<sub>2</sub>O<br />
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CH<sub>4</sub> + NH<sub>3</sub> &rarr; HCN + 3H<sub>2</sub> (BMA process)<br />
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CH<sub>4</sub> + NH<sub>3</sub> &rarr; HCN + 3H<sub>2</sub> (BMA process)<br />
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: CO + NH<sub>3</sub> &rarr; HCN + H<sub>2</sub>O<br />
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: CH<sub>4</sub> + NH<sub>3</sub> &rarr; HCN + 3H<sub>2</sub> ([[BMA process]])<br />
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The formaldehyde, ammonia, and HCN then react by Strecker synthesis to form amino acids and other biomolecules:<br />
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然后,甲醛、氨和 HCN 通过 Strecker合成反应生成氨基酸和其他生物分子:<br />
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The formaldehyde, ammonia, and HCN then react by [[Strecker synthesis]] to form amino acids and other biomolecules:<br />
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CH<sub>2</sub>O + HCN + NH<sub>3</sub> &rarr; NH<sub>2</sub>-CH<sub>2</sub>-CN + H<sub>2</sub>O<br />
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CH<sub>2</sub>O + HCN + NH<sub>3</sub> &rarr; NH<sub>2</sub>-CH<sub>2</sub>-CN + H<sub>2</sub>O<br />
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NH<sub>2</sub>-CH<sub>2</sub>-CN + 2H<sub>2</sub>O &rarr; NH<sub>3</sub> + NH<sub>2</sub>-CH<sub>2</sub>-COOH (glycine)<br />
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NH<sub>2</sub>-CH<sub>2</sub>-CN + 2H<sub>2</sub>O &rarr; NH<sub>3</sub> + NH<sub>2</sub>-CH<sub>2</sub>-COOH (glycine)<br />
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: CH<sub>2</sub>O + HCN + NH<sub>3</sub> &rarr; NH<sub>2</sub>-CH<sub>2</sub>-CN + H<sub>2</sub>O<br />
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: NH<sub>2</sub>-CH<sub>2</sub>-CN + 2H<sub>2</sub>O &rarr; NH<sub>3</sub> + NH<sub>2</sub>-CH<sub>2</sub>-COOH ([[glycine]])<br />
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Furthermore, water and formaldehyde can react, via Butlerov's reaction to produce various sugars like ribose.<br />
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此外,水和甲醛可以反应,通过巴特列罗夫的反应产生各种糖,如核糖。<br />
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Furthermore, water and formaldehyde can react, via [[Formose reaction|Butlerov's reaction]] to produce various [[sugar]]s like [[ribose]].<br />
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The experiments showed that simple organic compounds of building blocks of proteins and other macromolecules can be formed from gases with the addition of energy.<br />
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实验表明,在添加能量的情况下,气体可以形成简单的有机化合物,由蛋白质和其他大分子组成 。<br />
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The experiments showed that simple organic compounds of building blocks of proteins and other macromolecules can be formed from gases with the addition of energy.<br />
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This experiment inspired many others. In 1961, Joan Oró found that the nucleotide base adenine could be made from hydrogen cyanide (HCN) and ammonia in a water solution. His experiment produced a large amount of adenine, the molecules of which were formed from 5 molecules of HCN. <br />
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这个实验启发了许多其他人。1961年,琼·奥雷奥发现,在水溶液中,由氰化氢和氨制成的核苷酸碱基腺嘌呤。他的实验产生了大量的腺嘌呤,其分子由5个HCN分子组成。<br />
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==Other experiments其他实验==<br />
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Also, many amino acids are formed from HCN and ammonia under these conditions. <br />
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此外,许多氨基酸是由 HCN 和氨在这些条件下形成。<br />
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This experiment inspired many others. In 1961, [[Joan Oró]] found that the [[nucleotide]] base [[adenine]] could be made from [[hydrogen cyanide]] (HCN) and [[ammonia]] in a water solution. His experiment produced a large amount of adenine, the molecules of which were formed from 5 molecules of HCN.<ref>{{cite journal |vauthors=Oró J, Kimball AP |title=Synthesis of purines under possible primitive earth conditions. I. Adenine from hydrogen cyanide |journal=Archives of Biochemistry and Biophysics |volume=94|issue=2 |pages=217–27 |date=August 1961 |pmid=13731263 |doi=10.1016/0003-9861(61)90033-9}}</ref> <br />
这个实验启发了许多其他人。1961年,[[Joan Oró]]发现[[核苷酸]]碱基[[腺嘌呤]]可以由[[氰化氢]](HCN)和[[氨]]在水溶液中制成。他的实验产生了大量腺嘌呤,腺嘌呤分子由5个HCN分子组成。 <br />
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Experiments conducted later showed that the other RNA and DNA nucleobases could be obtained through simulated prebiotic chemistry with a reducing atmosphere.<br />
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后来进行的实验表明,其他 RNA 和 DNA 碱基可以通过模拟生命前化学在还原气氛下获得。<br />
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Also, many amino acids are formed from HCN and ammonia under these conditions.<ref>{{cite journal |vauthors=Oró J, Kamat SS |title=Amino-acid synthesis from hydrogen cyanide under possible primitive earth conditions |journal=Nature |volume=190 |issue= 4774|pages=442–3 |date=April 1961 |pmid=13731262 |doi=10.1038/190442a0|bibcode = 1961Natur.190..442O |url=https://www.semanticscholar.org/paper/1aea2775f328d439e5bb65e61fdf3b988d829052 }}</ref> <br />
此外,在这些条件下,许多氨基酸由HCN和氨形成 <br />
Experiments conducted later showed that the other [[Nucleobase|RNA and DNA nucleobases]] could be obtained through simulated prebiotic chemistry with a [[reducing atmosphere]].<ref>{{cite book | title=Origins of Prebiological Systems and of Their Molecular Matrices| editor= Fox SW| author=Oró J| year=1967| pages=137| publisher=New York Academic Press}}</ref><br />
随后进行的实验表明,另一种[[核碱基| RNA和DNA碱基]]可以通过模拟益生元化学和[[还原气氛]]获得 <br />
There also had been similar electric discharge experiments related to the origin of life contemporaneous with Miller–Urey. An article in The New York Times (March 8, 1953:E9), titled "Looking Back Two Billion Years" describes the work of Wollman (William) M. MacNevin at The Ohio State University, before the Miller Science paper was published in May 1953. MacNevin was passing 100,000 volt sparks through methane and water vapor and produced "resinous solids" that were "too complex for analysis." The article describes other early earth experiments being done by MacNevin. It is not clear if he ever published any of these results in the primary scientific literature.<!--is it not clear because academics have researched this and somehow can't tell, or is it just not clear to the Wikipedia contributor from reading only the NYT article?--><br />
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与米勒-尤里同时期也有过类似的与生命起源有关的放电实验。《纽约时报》(1953年3月8日:E9)上的一篇题为“回顾20亿年”的文章描述了1953年5月米勒科学论文发表之前,俄亥俄州立大学的沃尔曼(William)M.MacNevin的工作。麦克尼文通过甲烷和水蒸气产生10万伏特的火花,产生“树脂固体”,这些“树脂固体”过于复杂,无法分析。目前还不清楚他是否曾在原始科学文献中发表过这些结果。(不清楚是因为学者们已经对此进行了研究,不知何故无法判断,还是仅仅因为阅读了《纽约时报》的文章,维基百科的撰稿人就不清楚了?) <br />
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There also had been similar electric discharge experiments related to the [[origin of life]] contemporaneous with Miller–Urey. An article in ''[[The New York Times]]'' (March 8, 1953:E9), titled "Looking Back Two Billion Years" describes the work of Wollman (William) M. MacNevin at [[The Ohio State University]], before the Miller ''Science'' paper was published in May 1953. MacNevin was passing 100,000 volt sparks through methane and water vapor and produced "resinous solids" that were "too complex for analysis." The article describes other early earth experiments being done by MacNevin. It is not clear if he ever published any of these results in the primary scientific literature.<ref>{{cite book | title=History of Shock Waves, Explosions and Impact: A Chronological and Biographical Reference | publisher=[[Springer-Verlag]] | author=Krehl, Peter O. K. | year=2009 | pages=603}}</ref><!--is it not clear because academics have researched this and somehow can't tell, or is it just not clear to the Wikipedia contributor from reading only the NYT article?--><br />
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K. A. Wilde submitted a paper to Science on December 15, 1952, before Miller submitted his paper to the same journal on February 10, 1953. Wilde's paper was published on July 10, 1953. Wilde used voltages up to only 600 V on a binary mixture of carbon dioxide (CO<sub>2</sub>) and water in a flow system. He observed only small amounts of carbon dioxide reduction to carbon monoxide, and no other significant reduction products or newly formed carbon compounds.<br />
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1952年12月15日,K·A· 王尔德向《科学》杂志提交了一篇论文,之后米勒又于1953年2月10日向同一杂志提交了他的论文。王尔德的论文发表于1953年7月10日。王尔德使用的电压只有600v 对二氧化碳(CO2)和流动系统中的水的二元混合物。他观察到只有少量的二氧化碳减少为一氧化碳,没有其他重要的还原产物或新形成的碳化合物。<br />
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Other researchers were studying UV-photolysis of water vapor with carbon monoxide. They have found that various alcohols, aldehydes and organic acids were synthesized in reaction mixture.<br />
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其他研究人员正在研究水蒸气与一氧化碳的紫外光解反应。他们发现各种醇类、醛类和有机酸都是在反应混合物中合成的。<br />
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K. A. Wilde submitted a paper to ''Science'' on December 15, 1952, before Miller submitted his paper to the same journal on February 10, 1953. Wilde's paper was published on July 10, 1953.<ref>{{cite journal |last=Wilde |first=Kenneth A. |authorlink= |first2=Bruno J. |last2=Zwolinski |first3=Ransom B. |last3=Parlin |date=July 1953 |title=The Reaction Occurring in CO<sub>2</sub>, <sub>2</sub>O Mixtures in a High-Frequency Electric Arc |journal=[[Science (journal)|Science]] |volume=118 |issue=3054 |pages=43–44 |id= |doi=10.1126/science.118.3054.43-a |pmid=13076175 |bibcode=1953Sci...118...43W |df= }}</ref> Wilde used voltages up to only 600 V on a binary mixture of [[carbon dioxide]] (CO<sub>2</sub>) and water in a flow system. He observed only small amounts of carbon dioxide reduction to carbon monoxide, and no other significant reduction products or newly formed carbon compounds.<br />
1952年12月15日,王尔德向《科学》杂志提交了一篇论文,米勒在1953年2月10日向同一家杂志提交了他的论文。王尔德的论文发表于1953年7月10日。[17]王尔德在一个流动系统中使用了高达600V的二氧化碳(CO2)和水的二元混合物。他观察到只有少量二氧化碳还原成一氧化碳,没有其他显著的还原产物或新形成的碳化合物<br />
Other researchers were studying [[Ultraviolet|UV]]-[[photolysis]] of water vapor with [[carbon monoxide]]. They have found that various alcohols, aldehydes and organic acids were synthesized in reaction mixture.<ref>[https://doi.org/10.1007%2FBF00931407 Synthesis of organic compounds from carbon monoxide and water by UV photolysis] ''Origins of Life''. December 1978, Volume 9, Issue 2, pp 93-101<br />
其他研究人员正在研究水蒸气与[[一氧化碳]]的[[紫外线|紫外线]]-[[光解]]。他们发现在反应混合物中可以合成各种醇、醛和有机酸 <br />
More recent experiments by chemists Jeffrey Bada, one of Miller's graduate students, and Jim Cleaves at Scripps Institution of Oceanography of the University of California, San Diego were similar to those performed by Miller. However, Bada noted that in current models of early Earth conditions, carbon dioxide and nitrogen (N<sub>2</sub>) create nitrites, which destroy amino acids as fast as they form. <!--However, the early Earth may have had significant amounts of iron and carbonate minerals able to neutralize the effects of the nitrites. --> <!-- Please find a scientific paper that makes this statement before removing the tag -- and then the remark may be visible again --> When Bada performed the Miller-type experiment with the addition of iron and carbonate minerals, the products were rich in amino acids. This suggests the origin of significant amounts of amino acids may have occurred on Earth even with an atmosphere containing carbon dioxide and nitrogen.<br />
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米勒的研究生之一、化学家杰弗里·巴达和加州大学圣地亚哥斯克里普斯海洋学研究所的吉姆·克里夫斯最近的实验与米勒的实验相似。然而,Bada指出,在目前的早期地球条件模型中,二氧化碳和氮(N2)会产生亚硝酸盐,亚硝酸盐在氨基酸形成的同时也会被破坏。<!--然而,早期地球可能有大量的铁和碳酸盐矿物能够中和亚硝酸盐的影响。--> <!--在去掉标签之前,请先找到一篇科学论文来说明这一点——然后这句话可能会再次显现出来——当Bada进行米勒式实验,添加铁和碳酸盐矿物时,产品富含氨基酸。这表明,即使在含有二氧化碳和氮气的大气中,也可能有大量氨基酸的起源。 <br />
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Akiva Bar-nun, Hyman Hartman.</ref><br />
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More recent experiments by chemists Jeffrey Bada, one of Miller's graduate students, and Jim Cleaves at [[Scripps Institution of Oceanography]] of the [[University of California, San Diego]] were similar to those performed by Miller. However, Bada noted that in current models of early Earth conditions, carbon dioxide and [[nitrogen]] (N<sub>2</sub>) create [[nitrite]]s, which destroy amino acids as fast as they form. <!--However, the early Earth may have had significant amounts of iron and [[carbonate minerals]] able to neutralize the effects of the nitrites.{{Citation needed|date=January 2016}} --> <!-- Please find a scientific paper that makes this statement before removing the tag -- and then the remark may be visible again --> When Bada performed the Miller-type experiment with the addition of iron and carbonate minerals, the products were rich in amino acids. This suggests the origin of significant amounts of amino acids may have occurred on Earth even with an atmosphere containing carbon dioxide and nitrogen.<ref name=Fox>{{Cite news |last=Fox |first=Douglas |date=2007-03-28 |title=Primordial Soup's On: Scientists Repeat Evolution's Most Famous Experiment |periodical=Scientific American |series=History of Science |publisher=Scientific American Inc. |url=http://www.sciam.com/article.cfm?id=primordial-soup-urey-miller-evolution-experiment-repeated |accessdate=2008-07-09 }}<br>{{Cite journal | last1 = Cleaves | first1 = H. J. | last2 = Chalmers | first2 = J. H. | last3 = Lazcano | first3 = A. | last4 = Miller | first4 = S. L. | last5 = Bada | first5 = J. L. | title = A Reassessment of Prebiotic Organic Synthesis in Neutral Planetary Atmospheres | doi = 10.1007/s11084-007-9120-3 | journal = Origins of Life and Evolution of Biospheres | volume = 38 | issue = 2 | pages = 105–115 | year = 2008 | pmid = 18204914| bibcode = 2008OLEB...38..105C |url=http://www.astro.ulg.ac.be/~mouchet/BIOC0701-1/Cleaves-etal-2008.pdf |url-status=dead |archive-url=https://web.archive.org/web/20131107134729/http://www.astro.ulg.ac.be/~mouchet/BIOC0701-1/Cleaves-etal-2008.pdf |archive-date=2013-11-07 }}</ref><br />
米勒的研究生之一、化学家杰弗里·巴达和加州大学圣地亚哥斯克里普斯海洋学研究所的吉姆·克里夫斯最近的实验与米勒的实验相似。然而,巴达指出,在目前的早期地球条件模型中,二氧化碳和氮气(N2)产生亚硝酸盐,亚硝酸盐在氨基酸形成的同时就被破坏。Bada在进行Miller型实验时添加了铁和碳酸盐矿物,产物富含氨基酸。这表明,即使在含有二氧化碳和氮气的大气中,也可能有大量氨基酸的起源 <br />
Some evidence suggests that Earth's original atmosphere might have contained fewer of the reducing molecules than was thought at the time of the Miller–Urey experiment. There is abundant evidence of major volcanic eruptions 4 billion years ago, which would have released carbon dioxide, nitrogen, hydrogen sulfide (H<sub>2</sub>S), and sulfur dioxide (SO<sub>2</sub>) into the atmosphere. Experiments using these gases in addition to the ones in the original Miller–Urey experiment have produced more diverse molecules. The experiment created a mixture that was racemic (containing both L and D enantiomers) and experiments since have shown that "in the lab the two versions are equally likely to appear"; however, in nature, L amino acids dominate. Later experiments have confirmed disproportionate amounts of L or D oriented enantiomers are possible.<br />
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一些证据表明,地球原始大气层中还原分子的含量可能比 Miller-Urey 实验时所认为的要少。有大量的证据表明,40亿年前的大型火山爆发会向大气中释放二氧化碳、氮、硫化氢(H2S)和二氧化硫(SO2)。除了最初的 Miller-Urey 实验中使用的气体之外,使用这些气体的实验已经产生了更多样化的分子。该实验创造了一种外消旋体(包含L和D对映体)的混合物,此后的实验表明,“在实验室中,这两种化合物出现的可能性相等” ; 然而,在自然界中,l 氨基酸占主导地位。后来的实验证实了不成比例的L或D取向对映异构体是可能的。<br />
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==Earth's early atmosphere地球最早的大气层==<br />
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Originally it was thought that the primitive secondary atmosphere contained mostly ammonia and methane. However, it is likely that most of the atmospheric carbon was CO<sub>2</sub> with perhaps some CO and the nitrogen mostly N<sub>2</sub>. In practice gas mixtures containing CO, CO<sub>2</sub>, N<sub>2</sub>, etc. give much the same products as those containing CH<sub>4</sub> and NH<sub>3</sub> so long as there is no O<sub>2</sub>. The hydrogen atoms come mostly from water vapor. In fact, in order to generate aromatic amino acids under primitive earth conditions it is necessary to use less hydrogen-rich gaseous mixtures. Most of the natural amino acids, hydroxyacids, purines, pyrimidines, and sugars have been made in variants of the Miller experiment.<br />
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起初人们认为原始的二次大气主要含有氨和甲烷。但是,大气中的大部分碳可能是 CO2 ,也可能是一些 CO 和氮大部分是N2 。在实际应用中,含有 CO、 CO2 、 N2 等的混合气体。只要没有O 2 ,就可以给出与含 CH4和 NH3 相同的产品。氢原子主要来自水蒸气。事实上,为了在原始土壤条件下生成芳香族氨基酸,必须使用较少的富氢气体混合物。大多数天然氨基酸、羟基酸、嘌呤、嘧啶和糖都是米勒实验的变体。<br />
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Some evidence suggests that Earth's original atmosphere might have contained fewer of the reducing molecules than was thought at the time of the Miller–Urey experiment. There is abundant evidence of major volcanic eruptions 4 billion years ago, which would have released carbon dioxide, nitrogen, [[hydrogen sulfide]] (H<sub>2</sub>S), and [[sulfur dioxide]] (SO<sub>2</sub>) into the atmosphere.<ref name=Green>{{Cite journal|last=Green|first=Jack|title=Academic Aspects of Lunar Water Resources and Their Relevance to Lunar Protolife|journal=International Journal of Molecular Sciences|year=2011|volume=12|issue=9|pages=6051–6076|doi=10.3390/ijms12096051|pmid=22016644|pmc=3189768|ref=harv}}</ref> Experiments using these gases in addition to the ones in the original Miller–Urey experiment have produced more diverse molecules. The experiment created a mixture that was racemic (containing both L and D [[enantiomer]]s) and experiments since have shown that "in the lab the two versions are equally likely to appear";<ref name="NS">{{Cite news |date=2006-06-02 |title=Right-handed amino acids were left behind |periodical=[[New Scientist]] |publisher=Reed Business Information Ltd |issue=2554 |pages=18 |url=https://www.newscientist.com/channel/life/mg19025545.200-righthanded-amino-acids-were-left-behind.html |accessdate=2008-07-09 |url-status=live |archiveurl=https://web.archive.org/web/20081024211531/http://www.newscientist.com/channel/life/mg19025545.200-righthanded-amino-acids-were-left-behind.html |archivedate=2008-10-24 }}</ref> however, in nature, L amino acids dominate. Later experiments have confirmed disproportionate amounts of L or D oriented enantiomers are possible.<ref>{{cite journal |last=Kojo |first=Shosuke |first2=Hiromi |last2=Uchino |first3=Mayu |last3=Yoshimura |first4=Kyoko |last4=Tanaka |date=October 2004 |title=Racemic D,L-asparagine causes enantiomeric excess of other coexisting racemic D,L-amino acids during recrystallization: a hypothesis accounting for the origin of L-amino acids in the biosphere |journal=Chemical Communications |volume= |issue=19 |pages=2146–2147 |pmid=15467844 |doi=10.1039/b409941a}}</ref><br />
一些证据表明,地球原始大气中含有的还原分子可能比米勒-尤里实验时所认为的要少。有大量证据表明,40亿年前的大型火山喷发会向大气中释放二氧化碳、氮气、硫化氢(H2S)和二氧化硫(SO2)。[20]除了最初米勒-尤里(Miller-Urey)实验中的实验外,使用这些气体的实验产生了更多不同的分子。实验产生了一种外消旋的混合物(同时含有L和D对映体),此后的实验表明,“在实验室中,两种对映体出现的可能性相等”;然而,在自然界中,L氨基酸占主导地位。后来的实验证实了不相称数量的L或D取向的对映体是可能的。 <br />
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More recent results may question these conclusions. The University of Waterloo and University of Colorado conducted simulations in 2005 that indicated that the early atmosphere of Earth could have contained up to 40 percent hydrogen—implying a much more hospitable environment for the formation of prebiotic organic molecules. The escape of hydrogen from Earth's atmosphere into space may have occurred at only one percent of the rate previously believed based on revised estimates of the upper atmosphere's temperature. One of the authors, Owen Toon notes: "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept... I think this study makes the experiments by Miller and others relevant again." Outgassing calculations using a chondritic model for the early earth complement the Waterloo/Colorado results in re-establishing the importance of the Miller–Urey experiment.<br />
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最近的研究结果可能会质疑这些结论。滑铁卢大学和科罗拉多大学在2005年进行了模拟,结果表明地球早期大气中可能含有高达40%的氢,这意味着有利于形成益生元有机分子的环境更加有利。氢从地球大气层逃逸到太空的速度可能只有先前根据对高层大气温度的修正估计所相信的速率的百分之一。作者之一欧文·图恩指出:“在这个新的场景中,有机物可以在早期大气中高效地产生,这让我们回到海洋中富含有机物的汤的概念。。。我认为这项研究使米勒和其他人的实验再次具有相关性。“利用早期地球的球粒陨石模型进行放气计算,补充了滑铁卢/科罗拉多的结果,重新确立了米勒-乌雷实验的重要性<br />
Originally it was thought that the primitive [[secondary atmosphere]] contained mostly ammonia and methane. However, it is likely that most of the atmospheric carbon was CO<sub>2</sub> with perhaps some CO and the nitrogen mostly N<sub>2</sub>. In practice gas mixtures containing CO, CO<sub>2</sub>, N<sub>2</sub>, etc. give much the same products as those containing CH<sub>4</sub> and NH<sub>3</sub> so long as there is no O<sub>2</sub>. The hydrogen atoms come mostly from water vapor. In fact, in order to generate aromatic amino acids under primitive earth conditions it is necessary to use less hydrogen-rich gaseous mixtures. Most of the natural amino acids, [[hydroxy acid|hydroxyacids]], purines, pyrimidines, and sugars have been made in variants of the Miller experiment.<ref name=bada2013/><ref>{{cite journal|last1=Ruiz-Mirazo|first1=Kepa|last2=Briones|first2=Carlos|last3=de la Escosura|first3=Andrés|title=Prebiotic Systems Chemistry: New Perspectives for the Origins of Life|journal=Chemical Reviews|year=2014|volume=114|issue=1|pages=285–366|doi=10.1021/cr2004844|pmid=24171674}}</ref><br />
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最初人们认为原始的二次大气主要含有氨和甲烷。然而,大气中的碳很可能大部分是二氧化碳,也许还有一些一氧化碳,氮主要是氮气。实际上,只要没有氧气,含有CO、CO2、N2等的气体混合物产生的产物与含有CH4和NH3的气体混合物的产物基本相同。氢原子主要来自水蒸气。事实上,为了在原始地球条件下产生芳香族氨基酸,有必要使用较少的富氢气体混合物。大多数天然氨基酸、羟基酸、嘌呤、嘧啶和糖都是在米勒实验的变体中制造的 <br />
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In contrast to the general notion of early earth's reducing atmosphere, researchers at the Rensselaer Polytechnic Institute in New York reported the possibility of oxygen available around 4.3 billion years ago. Their study reported in 2011 on the assessment of Hadean zircons from the earth's interior (magma) indicated the presence of oxygen traces similar to modern-day lavas. This study suggests that oxygen could have been released in the earth's atmosphere earlier than generally believed.<br />
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与早期地球还原大气层的普遍观点不同,纽约伦斯勒理工学院的研究人员在43亿年前报告了氧气的可能性。他们在2011年报告了对来自地球内部(岩浆)的哈迪恩锆石的评估研究,研究表明存在类似于现代熔岩的氧气痕迹。这项研究表明,氧气在地球大气中释放的时间可能比人们通常认为的要早。<br />
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More recent results may question these conclusions. The University of Waterloo and University of Colorado conducted simulations in 2005 that indicated that the early atmosphere of Earth could have contained up to 40 percent hydrogen—implying a much more hospitable environment for the formation of prebiotic organic molecules. The escape of hydrogen from Earth's atmosphere into space may have occurred at only one percent of the rate previously believed based on revised estimates of the upper atmosphere's temperature.<ref>{{cite web |url=http://newsrelease.uwaterloo.ca/news.php?id=4348 |accessdate=2005-12-17 |title=Early Earth atmosphere favorable to life: study |publisher=University of Waterloo |url-status=dead |archiveurl=https://web.archive.org/web/20051214230357/http://newsrelease.uwaterloo.ca/news.php?id=4348 |archivedate=2005-12-14 }}</ref> One of the authors, Owen Toon notes: "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept... I think this study makes the experiments by Miller and others relevant again." Outgassing calculations using a chondritic model for the early earth complement the Waterloo/Colorado results in re-establishing the importance of the Miller–Urey experiment.<ref>{{cite web |url=http://news-info.wustl.edu/news/page/normal/5513.html |accessdate=2005-12-17 |title=Calculations favor reducing atmosphere for early earth – Was Miller–Urey experiment correct? |first=Tony |last=Fitzpatrick |publisher=Washington University in St. Louis |year=2005 |url-status=dead |archiveurl=https://web.archive.org/web/20080720174657/http://news-info.wustl.edu/news/page/normal/5513.html |archivedate=2008-07-20 }}</ref><br />
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最近的研究结果可能会质疑这些结论。滑铁卢大学和科罗拉多大学在2005年进行了模拟,结果表明地球早期大气中可能含有高达40%的氢,这意味着有利于形成益生元有机分子的环境更加有利。氢从地球大气层逃逸到太空的速度可能只有先前根据对高层大气温度的修正估计而认为的速率的百分之一。[24]作者之一欧文·图恩指出:“在这种新的情况下,早期大气中可以有效地产生有机物,带我们回到海洋中有机丰富的汤的概念。我认为这项研究使米勒和其他人的实验再次具有相关性。“利用早期地球的球粒陨石模型进行放气计算,补充了滑铁卢/科罗拉多州的结果,重新确立了米勒-尤里实验的重要性 <br />
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In contrast to the general notion of early earth's reducing atmosphere, researchers at the [[Rensselaer Polytechnic Institute]] in New York reported the possibility of oxygen available around 4.3 billion years ago. Their study reported in 2011 on the assessment of Hadean [[zircons]] from the earth's interior ([[magma]]) indicated the presence of oxygen traces similar to modern-day lavas.<ref>{{cite journal|last1=Trail|first1=Dustin|last2=Watson|first2=E. Bruce|last3=Tailby|first3=Nicholas D.|title=The oxidation state of Hadean magmas and implications for early Earth's atmosphere|journal=Nature|year=2011|volume=480|issue=7375|pages=79–82|doi=10.1038/nature10655|pmid=22129728|bibcode=2011Natur.480...79T|url=https://www.semanticscholar.org/paper/e87ff5db353f56ac40649b2a4ca618f3c2067cdb}}</ref> This study suggests that oxygen could have been released in the earth's atmosphere earlier than generally believed.<ref>{{cite journal|last1=Scaillet|first1=Bruno|last2=Gaillard|first2=Fabrice|title=Earth science: Redox state of early magmas|journal=Nature|date=2011|volume=480|issue=7375|pages=48–49|doi=10.1038/480048a|pmid=22129723|bibcode=2011Natur.480...48S|url=https://hal.archives-ouvertes.fr/file/index/docid/648930/filename/Scaillet-Nature2-2011.pdf|url-status=live|archiveurl=https://web.archive.org/web/20171026110646/https://hal.archives-ouvertes.fr/file/index/docid/648930/filename/Scaillet-Nature2-2011.pdf|archivedate=2017-10-26|citeseerx=10.1.1.659.2086}}</ref><br />
与早期地球大气还原的一般观念不同,纽约伦斯勒理工学院的研究人员报告说,大约43亿年前,有可能存在氧气。他们在2011年对来自地球内部(岩浆)的Hadean锆石进行评估的研究表明,存在着类似于现代熔岩的氧痕迹。这项研究表明,地球大气中的氧气可能比一般认为的更早释放。<br />
Conditions similar to those of the Miller–Urey experiments are present in other regions of the solar system, often substituting ultraviolet light for lightning as the energy source for chemical reactions. The Murchison meteorite that fell near Murchison, Victoria, Australia in 1969 was found to contain over 90 different amino acids, nineteen of which are found in Earth life. Comets and other icy outer-solar-system bodies are thought to contain large amounts of complex carbon compounds (such as tholins) formed by these processes, darkening surfaces of these bodies. The early Earth was bombarded heavily by comets, possibly providing a large supply of complex organic molecules along with the water and other volatiles they contributed. This has been used to infer an origin of life outside of Earth: the panspermia hypothesis.<br />
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类似 Miller-Urey 实验的条件在太阳系的其他区域也存在,常常以紫外线代替闪电作为化学反应的能源。1969年落在默奇森河附近的默奇森陨石被发现含有超过90种不同的氨基酸,其中十九种存在于地球生命中。彗星和其他太阳系外围冰冷的天体被认为含有大量复杂的碳化合物(例如塞林) ,这些碳化合物是由这些天体的暗化表面形成的。早期的地球被彗星大量撞击,可能提供了大量复杂的有机分子以及它们贡献的水和其他挥发物。这被用来推断地球以外生命的起源: 胚种说。<br />
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==Extraterrestrial sources外星源==<br />
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Conditions similar to those of the Miller–Urey experiments are present in other regions of the [[solar system]], often substituting [[ultraviolet]] light for lightning as the energy source for chemical reactions.<ref>{{cite journal|last1=Nunn|first1=JF|title=Evolution of the atmosphere|journal=Proceedings of the Geologists' Association. Geologists' Association|year=1998|volume=109|issue=1|pages=1–13|pmid=11543127|doi=10.1016/s0016-7878(98)80001-1}}</ref><ref>{{cite journal|last1=Raulin|first1=F|last2=Bossard|first2=A|title=Organic syntheses in gas phase and chemical evolution in planetary atmospheres.|journal=Advances in Space Research|year=1984|volume=4|issue=12|pages=75–82|pmid=11537798|doi=10.1016/0273-1177(84)90547-7|bibcode=1984AdSpR...4...75R}}</ref><ref>{{cite journal|last1=Raulin|first1=François|last2=Brassé|first2=Coralie|last3=Poch|first3=Olivier|last4=Coll|first4=Patrice|title=Prebiotic-like chemistry on Titan|journal= Chemical Society Reviews|year=2012|volume=41|issue=16|pages=5380–93|doi=10.1039/c2cs35014a|pmid=22481630}}</ref> The [[Murchison meteorite]] that fell near [[Murchison, Victoria]], Australia in 1969 was found to contain over 90 different amino acids, nineteen of which are found in Earth life. [[Comet]]s and other [[Trans-Neptunian object|icy outer-solar-system bodies]] are thought to contain large amounts of complex carbon compounds (such as [[tholin]]s) formed by these processes, darkening surfaces of these bodies.<ref>{{cite journal |vauthors=Thompson WR, Murray BG, Khare BN, Sagan C |title=Coloration and darkening of methane clathrate and other ices by charged particle irradiation: applications to the outer solar system |journal=Journal of Geophysical Research |volume=92 |issue=A13 |pages=14933–47 |date=December 1987 |pmid=11542127 |doi=10.1029/JA092iA13p14933 |bibcode=1987JGR....9214933T|title-link=methane clathrate }}</ref> The early Earth was bombarded heavily by comets, possibly providing a large supply of complex organic molecules along with the water and other volatiles they contributed.<ref>{{cite journal|last=PIERAZZO|first=E.|author2=CHYBA C.F.|title=Amino acid survival in large cometary impacts|journal=Meteoritics & Planetary Science|year=2010|volume=34|issue=6|pages=909–918|doi=10.1111/j.1945-5100.1999.tb01409.x|bibcode=1999M&PS...34..909P}}</ref> This has been used to infer an origin of life outside of Earth: the [[panspermia]] hypothesis.<br />
与米勒-尤里实验相似的条件也存在于太阳系的其他区域,通常用紫外线代替闪电作为化学反应的能源。1969年落在澳大利亚维多利亚州默奇森附近的莫奇森陨石被发现含有90多种不同的氨基酸,地球上有19个生命。彗星和其他冰冷的太阳系外天体被认为含有大量由这些过程形成的复杂碳化合物(如索林类化合物),使这些天体的表面变暗。早期地球受到彗星的猛烈轰炸,可能与水和其他挥发物一起提供了大量复杂的有机分子他们对此作出了贡献。这被用来推断地球外生命的起源:胚种假说。<br />
In recent years, studies have been made of the amino acid composition of the products of "old" areas in "old" genes, defined as those that are found to be common to organisms from several widely separated species, assumed to share only the last universal ancestor (LUA) of all extant species. These studies found that the products of these areas are enriched in those amino acids that are also most readily produced in the Miller–Urey experiment. This suggests that the original genetic code was based on a smaller number of amino acids – only those available in prebiotic nature – than the current one.<br />
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近年来,人们对“老”基因中“老”区域产物的氨基酸组成进行了研究,这些“老”基因被定义为是几种广泛分离的物种的有机体所共有的氨基酸成分,假设它们只共享所有现存物种的最后一个宇宙祖先(LUA)。这些研究发现,这些区域的产物富含那些在 Miller-Urey 实验中也最容易产生的氨基酸。这表明,最初的遗传密码是基于比现在更少的氨基酸-只有那些具有益生元性质的氨基酸<br />
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==Recent related studies近年相关研究==<br />
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Jeffrey Bada, himself Miller's student, inherited the original equipment from the experiment when Miller died in 2007. Based on sealed vials from the original experiment, scientists have been able to show that although successful, Miller was never able to find out, with the equipment available to him, the full extent of the experiment's success. Later researchers have been able to isolate even more different amino acids, 25 altogether. Bada has estimated that more accurate measurements could easily bring out 30 or 40 more amino acids in very low concentrations, but the researchers have since discontinued the testing. Miller's experiment was therefore a remarkable success at synthesizing complex organic molecules from simpler chemicals, considering that all known life uses just 20 different amino acids.<br />
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杰弗里·巴达(Jeffrey Bada)是米勒的学生,他在2007年米勒去世时继承了这项实验的原始设备。根据最初实验中的密封小瓶,科学家们已经能够证明,虽然米勒成功了,但在现有设备的情况下,米勒始终无法发现实验成功的全部程度。后来的研究人员已经能够分离出更多不同的氨基酸,总共25种。Bada估计,更精确的测量可以很容易地在非常低的浓度下提取出30或40种氨基酸,但是研究人员已经停止了这项测试。考虑到所有已知生命只使用20种不同的氨基酸,米勒的实验因此在从较简单的化学物质合成复杂有机分子方面取得了显著成功。<br />
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In recent years, studies have been made of the [[amino acid]] composition of the products of "old" areas in "old" genes, defined as those that are found to be common to organisms from several widely separated [[species]], assumed to share only the [[last universal ancestor]] (LUA) of all extant species. These studies found that the products of these areas are enriched in those amino acids that are also most readily produced in the Miller–Urey experiment. This suggests that the original genetic code was based on a smaller number of amino acids – only those available in prebiotic nature – than the current one.<ref>{{cite journal |author1=Brooks D.J. |author2=Fresco J.R. |author3=Lesk A.M. |author4=Singh M. |url=http://mbe.oupjournals.org/cgi/content/full/19/10/1645 |title=Evolution of amino acid frequencies in proteins over deep time: inferred order of introduction of amino acids into the genetic code |journal=Molecular Biology and Evolution |date=October 1, 2002 |volume=19 |pages=1645–55 |pmid=12270892 |issue=10 |doi=10.1093/oxfordjournals.molbev.a003988 |url-status=dead |archiveurl=https://web.archive.org/web/20041213094516/http://mbe.oupjournals.org/cgi/content/full/19/10/1645 |archivedate=December 13, 2004 |doi-access=free }}</ref><br />
近年来,人们对“老”基因中“老”区域产物的氨基酸组成进行了研究,这些“老”基因被定义为是几种广泛分离的物种的有机体所共有的氨基酸成分,假设它们只共享所有现存物种的最后一个宇宙祖先(LUA)。这些研究发现,这些地区的产品富含在米勒-尤里实验中最容易产生的氨基酸。这表明,最初的遗传密码是基于比现在更少的氨基酸-只有那些在益生元性质-比目前的<br />
<br />
<br />
In 2008, a group of scientists examined 11 vials left over from Miller's experiments of the early 1950s. In addition to the classic experiment, reminiscent of Charles Darwin's envisioned "warm little pond", Miller had also performed more experiments, including one with conditions similar to those of volcanic eruptions. This experiment had a nozzle spraying a jet of steam at the spark discharge. By using high-performance liquid chromatography and mass spectrometry, the group found more organic molecules than Miller had. They found that the volcano-like experiment had produced the most organic molecules, 22 amino acids, 5 amines and many hydroxylated molecules, which could have been formed by hydroxyl radicals produced by the electrified steam. The group suggested that volcanic island systems became rich in organic molecules in this way, and that the presence of carbonyl sulfide there could have helped these molecules form peptides.<br />
<br />
2008年,一组科学家检查了米勒20世纪50年代早期实验遗留下来的11个小瓶。除了经典的实验(让人想起查尔斯·达尔文设想的“温暖的小池塘”)外,米勒还进行了更多的实验,其中一个实验的条件与火山爆发时相似。这个实验有一个喷嘴在火花放电处喷射蒸汽。通过使用高效液相色谱和质谱,研究小组发现了比米勒更多的有机分子。他们发现,类似火山的实验产生了最多的有机分子,22个氨基酸,5个胺和许多羟基化分子,这些分子可能是由通电蒸汽产生的羟基自由基形成的。研究小组认为,火山岛系统以这种方式富含有机分子,而羰基硫化物的存在可能有助于这些分子形成肽。 <br />
[[Jeffrey Bada]], himself Miller's student, inherited the original equipment from the experiment when Miller died in 2007. Based on sealed vials from the original experiment, scientists have been able to show that although successful, Miller was never able to find out, with the equipment available to him, the full extent of the experiment's success. Later researchers have been able to isolate even more different amino acids, 25 altogether. Bada has estimated that more accurate measurements could easily bring out 30 or 40 more amino acids in very low concentrations, but the researchers have since discontinued the testing. Miller's experiment was therefore a remarkable success at synthesizing complex organic molecules from simpler chemicals, considering that all known life uses just 20 different amino acids.<ref name="BBC">{{cite web |website=BBC Four |url=http://www.bbc.co.uk/programmes/b00mbvfh |title=The Spark of Life |url-status=live |archive-url=https://web.archive.org/web/20101113011054/http://www.bbc.co.uk/programmes/b00mbvfh |archive-date=2010-11-13 |postscript=. TV Documentary. |date=26 August 2009}}</ref><br />
杰弗里·巴达(Jeffrey Bada)是米勒的学生,他在2007年米勒去世时继承了这项实验的原始设备。根据最初实验中的密封小瓶,科学家们已经能够证明,虽然米勒成功了,但在现有设备的情况下,米勒始终无法发现实验成功的全部程度。后来的研究人员已经能够分离出更多不同的氨基酸,总共25种。Bada估计,更精确的测量可以很容易地在非常低的浓度下提取出30或40种氨基酸,但是研究人员已经停止了这项测试。考虑到所有已知生命只使用20种不同的氨基酸,米勒的实验因此在从较简单的化学物质合成复杂有机分子方面取得了显著成功。<br />
<br />
<br />
The main problem of theories based around amino acids is the difficulty in obtaining spontaneous formation of peptides. Since John Desmond Bernal's suggestion that clay surfaces could have played a role in abiogenesis, scientific efforts have been dedicated to investigating clay-mediated peptide bond formation, with limited success. Peptides formed remained over-protected and shown no evidence of inheritance or metabolism. In December 2017 a theoretical model developed by Erastova and collaborators suggested that peptides could form at the interlayers of layered double hydroxides such as green rust in early earth conditions. According to the model, drying of the intercalated layered material should provide energy and co-alignment required for peptide bond formation in a ribosome-like fashion, while re-wetting should allow mobilising the newly formed peptides and repopulate the interlayer with new amino acids. This mechanism is expected to lead to the formation of 12+ amino acid-long peptides within 15-20 washes. Researches also observed slightly different adsorption preferences for different amino acids, and postulated that, if coupled to a diluted solution of mixed amino acids, such preferences could lead to sequencing.<br />
<br />
以氨基酸为基础的理论的主要问题是很难获得肽的自发形成。自从约翰·德斯蒙德·伯纳尔提出粘土表面可能在自然发生中起作用以来,科学家致力于研究粘土介导的肽键的形成,但成效有限。形成的肽保护过度,没有遗传或新陈代谢的证据。2017年12月,Erastova和他的合作者开发的一个理论模型表明,在早期的地球条件下,多肽可以在层状双氢氧化物的中间层形成,例如绿锈。根据该模型,插层材料的干燥应提供能量和以核糖体样的方式形成肽键所需的共排列,而再湿润应允许活化新形成的肽和重新填充层与新的氨基酸。这一机制有望在15-20次洗涤过程中形成12 + 氨基酸长肽。研究人员还观察到对不同氨基酸的吸附偏好略有不同,并假定,如果与混合氨基酸的稀释溶液相结合,这种偏好可能导致排序。<br />
<br />
In 2008, a group of scientists examined 11 vials left over from Miller's experiments of the early 1950s. In addition to the classic experiment, reminiscent of [[Charles Darwin]]'s envisioned "warm little pond", Miller had also performed more experiments, including one with conditions similar to those of [[volcano|volcanic]] eruptions. This experiment had a nozzle spraying a jet of steam at the spark discharge. By using [[high-performance liquid chromatography]] and [[mass spectrometry]], the group found more organic molecules than Miller had. They found that the volcano-like experiment had produced the most organic molecules, 22 amino acids, 5 [[amine]]s and many [[hydroxylate]]d molecules, which could have been formed by [[hydroxyl radical]]s produced by the electrified steam. The group suggested that volcanic island systems became rich in organic molecules in this way, and that the presence of [[carbonyl sulfide]] there could have helped these molecules form [[peptide]]s.<ref name=Johnson2008>{{cite journal |vauthors=Johnson AP, Cleaves HJ, Dworkin JP, Glavin DP, Lazcano A, Bada JL |title=The Miller volcanic spark discharge experiment |journal=Science |volume=322 |issue=5900 |pages=404 |date=October 2008 |pmid=18927386 |doi=10.1126/science.1161527|bibcode = 2008Sci...322..404J }}</ref><ref>{{cite web | title='Lost' Miller–Urey Experiment Created More Of Life's Building Blocks | date=October 17, 2008 | website=Science Daily | url=https://www.sciencedaily.com/releases/2008/10/081016141411.htm | accessdate=2008-10-18 | url-status=live | archiveurl=https://web.archive.org/web/20081019111114/http://www.sciencedaily.com/releases/2008/10/081016141411.htm | archivedate=October 19, 2008 }}</ref><br />
20世纪50年代,除了经典的实验,让人想起查尔斯达尔文设想的“温暖的小池塘”,米勒还进行了更多的实验,包括一个条件类似于火山喷发的实验。这个实验有一个喷嘴在火花放电处喷射蒸汽。通过液相色谱法和质谱法发现了比米勒组更多的有机分子。他们发现,类似火山的实验产生了最多的有机分子,22个氨基酸,5个胺和许多羟基化分子,这些分子可能是由通电蒸汽产生的羟基自由基形成的。该小组认为,火山岛系统通过这种方式变得富含有机分子,而那里的羰基硫化物可能有助于这些分子形成肽。<br />
<br />
<br />
In October 2018, researchers at McMaster University on behalf of the Origins Institute announced the development of a new technology, called a Planet Simulator, to help study the origin of life on planet Earth and beyond.<br />
<br />
2018年10月,麦马士达大学的研究人员代表起源研究所宣布了一项名为行星模拟器的新技术的发展,以帮助研究行星地球及其他地方的生命起源。<br />
<br />
The main problem of theories based around [[amino acids]] is the difficulty in obtaining spontaneous formation of peptides. Since [[John Desmond Bernal]]'s suggestion that clay surfaces could have played a role in [[abiogenesis]]<ref name=Bernal1949>{{cite journal |vauthors=Bernal JD |title=The physical basis of life |journal=Proc. Phys. Soc. A | issue=9 |volume=62 |pages=537–558 |date=1949|doi=10.1088/0370-1298/62/9/301 |bibcode=1949PPSA...62..537B }}</ref>, scientific efforts have been dedicated to investigating clay-mediated [[peptide bond]] formation, with limited success. Peptides formed remained over-protected and shown no evidence of inheritance or metabolism. In December 2017 a theoretical model developed by Erastova and collaborators <ref name="RT-2018">{{cite news | publisher=RT | url=https://www.rt.com/news/416581-scientists-unlock-life-puzzle-protein/ | title='How did life form from rocks?' Protein puzzle reveals secrets of Earth's evolution | date=January 2017}}</ref><ref name="Erastova2017">{{cite journal |vauthors=Erastova V, Degiacomi MT, Fraser D, Greenwell HC |title=Mineral surface chemistry control for origin of prebiotic peptides |journal=Nature Communications |volume=8 |issue=1 |pages=2033 |date=December 2017|pmid=29229963 |pmc=5725419 |doi=10.1038/s41467-017-02248-y |bibcode=2017NatCo...8.2033E }}</ref> suggested that peptides could form at the interlayers of [[layered double hydroxides]] such as [[green rust]] in early earth conditions. According to the model, drying of the intercalated layered material should provide energy and co-alignment required for peptide bond formation in a [[ribosome]]-like fashion, while re-wetting should allow mobilising the newly formed peptides and repopulate the interlayer with new amino acids. This mechanism is expected to lead to the formation of 12+ amino acid-long peptides within 15-20 washes. Researches also observed slightly different adsorption preferences for different amino acids, and postulated that, if coupled to a diluted solution of mixed amino acids, such preferences could lead to sequencing.<br />
以氨基酸为基础的理论的主要问题是难以获得肽的自发形成。自从John Desmond Bernal提出粘土表面可能在非生物发生中起作用[36]以来,科学界一直致力于研究粘土介导的肽键形成,但收效甚微。形成的肽仍然受到过度保护,没有遗传或代谢的证据。2017年12月,Erastova及其合作者开发的一个理论模型表明,在早期地球条件下,肽可以在层状双氢氧化物(如绿锈)的层间形成。根据该模型,夹层材料的干燥应能以类似假种体的方式提供肽键形成所需的能量和协同排列,而再润湿应能使新形成的肽活化,并在夹层中重新填充新的氨基酸。这一机制有望在15-20次洗涤过程中形成12+氨基酸长肽。研究还观察到不同氨基酸的吸附偏好稍有不同,并假设,如果与混合氨基酸的稀释溶液相结合,这种偏好可能导致测序。<br />
<br />
<br />
In October 2018, researchers at [[McMaster University]] on behalf of the [[Origins Institute]] announced the development of a new technology, called a ''[[Planet Simulator]]'', to help study the [[origin of life]] on planet [[Earth]] and beyond.<ref name="BW-20181004">{{cite news |last=Balch |first=Erica |title=Ground-breaking lab poised to unlock the mystery of the origins of life on Earth and beyond |url=https://brighterworld.mcmaster.ca/articles/ground-breaking-lab-poised-to-unlock-the-mystery-of-the-origins-of-life-on-earth-and-beyond/ |date=4 October 2018 |work=[[McMaster University]] |accessdate=4 October 2018 }}</ref><ref name="EA-20181004">{{cite news |author=Staff |title=Ground-breaking lab poised to unlock the mystery of the origins of life |url=https://www.eurekalert.org/pub_releases/2018-10/mu-glp100418.php |date=4 October 2018 |work=[[EurekAlert!]] |accessdate=14 October 2018 }}</ref><ref name="IVG-2018">{{cite web |author=Staff |title=Planet Simulator |url=https://www.intravisiongroup.com/planet-simulator |date=2018 |work=IntraVisionGroup.com |accessdate=14 October 2018 }}</ref><ref name="ES-209181014">{{cite web |last=Anderson |first=Paul Scott |title=New technology may help solve mystery of life's origins - How did life on Earth begin? A new technology, called Planet Simulator, might finally help solve the mystery. |url=http://earthsky.org/space/new-technology-solve-mystery-of-lifes-origins |date=14 October 2018 |work=[[EarthSky]] |accessdate=14 October 2018 }}</ref><br />
<br />
2018年10月,麦克马斯特大学(McMaster University)的研究人员代表起源研究所(Origins Institute)宣布开发一种新技术,名为“行星模拟器”(Planet Simulator),以帮助研究行星地球及其他星球上生命的起源。<br />
<br />
==Amino acids identified氨基酸鉴定 ==<br />
<br />
Below is a table of amino acids produced and identified in the "classic" 1952 experiment, as published by Miller in 1953, and the 2010 re-analysis of vials from the H<sub>2</sub>S-rich spark discharge experiment.<br />
<br />
下面是由 Miller 在1953年发表的1952年“经典”实验中产生和鉴定的氨基酸表,以及2010年对H2S高密度火花放电实验中小瓶的重新分析。<br />
<br />
{{Category see also|Chemical synthesis of amino acids}}<br />
<br />
<br />
<br />
{|class="wikitable sortable" style="text-align:right"<br />
<br />
{ | class = “ wikitable sortable” style = “ text-align: right”<br />
<br />
Below is a table of amino acids produced and identified in the "classic" 1952 experiment, as published by Miller in 1953,<ref name=miller1953/> the 2008 re-analysis of vials from the volcanic spark discharge experiment,<ref>{{cite web|last1=Myers|first1=P. Z.|title=Old scientists never clean out their refrigerators|url=http://scienceblogs.com/pharyngula/2008/10/old_scientists_never_clean_out.php|website=Pharyngula|accessdate=7 April 2016|archiveurl=https://web.archive.org/web/20081017231050/http://scienceblogs.com/pharyngula/2008/10/old_scientists_never_clean_out.php|archivedate=October 17, 2008|date=October 16, 2008}}</ref> and the 2010 re-analysis of vials from the H<sub>2</sub>S-rich spark discharge experiment.<ref>{{cite journal|title=Primordial synthesis of amines and amino acids in a 1958 Miller H2S-rich spark discharge experiment|journal=Proceedings of the National Academy of Sciences|date=February 14, 2011|volume=108|issue=14|doi=10.1073/pnas.1019191108|pmid=21422282|pmc=3078417|pages=5526–31|last1=Parker|first1=ET|last2=Cleaves|first2=HJ|last3=Dworkin|first3=JP|display-authors=etal |bibcode=2011PNAS..108.5526P|df=}}</ref><br />
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|-<br />
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|-<br />
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! scope="col" rowspan="2" | Amino acid<br />
<br />
!范围 = “ col” rowspan = “2” | 氨基酸<br />
<br />
{|class="wikitable sortable" style="text-align:right"<br />
<br />
! scope="col" colspan="3" | Produced in experiment<br />
<br />
!在实验中产生<br />
<br />
|-<br />
<br />
! scope="col" rowspan="2" | Proteinogenic<br />
<br />
!Scope = “ col” rowspan = “2” | Proteinogenic<br />
<br />
! scope="col" rowspan="2" | Amino acid<br />
<br />
|-<br />
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|-<br />
<br />
! scope="col" colspan="3" | Produced in experiment<br />
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! scope="col" | Miller–Urey<br/><br />
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!“ col” | Miller-Urey < br/> <br />
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! scope="col" rowspan="2" | [[Proteinogenic]]<br />
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! scope="col" | Volcanic spark discharge<br/><br />
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!火山火花放电 < br/> <br />
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|-<br />
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! scope="col" | H<sub>2</sub>S-rich spark discharge<br/><br />
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!范围 = “ col” | h < sub > 2 </sub > 富 s 火花放电 < br/> <br />
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! scope="col" | Miller–Urey<br/>{{small|(1952)}}<br />
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|-<br />
<br />
|-<br />
<br />
! scope="col" | Volcanic spark discharge<br/>{{small|(2008)}}<br />
<br />
|Glycine<br />
<br />
| 甘氨酸<br />
<br />
! scope="col" | H<sub>2</sub>S-rich spark discharge<br/>{{small|(2010)}}<br />
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| <br />
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| <br />
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|<br />
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|[[Glycine]]<br />
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| <br />
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|<br />
<br />
| {{ya}}<br />
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| <br />
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|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|α-Alanine<br />
<br />
|α-Alanine<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[alanine|α-Alanine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|β-Alanine<br />
<br />
|β-Alanine<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[beta-Alanine|β-Alanine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Aspartic acid<br />
<br />
天冬氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
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|-<br />
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| <br />
<br />
|<br />
<br />
|[[Aspartic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|α-Aminobutyric acid<br />
<br />
|α-Aminobutyric acid<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[alpha-Aminobutyric acid|α-Aminobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Serine<br />
<br />
| Serine<br />
<br />
| {{no}}<br />
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| <br />
<br />
|<br />
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|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Serine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
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| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Isoserine<br />
<br />
| 异丝氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Isoserine]]<br />
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| <br />
<br />
|<br />
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| {{na}}<br />
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| <br />
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|<br />
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| {{ya}}<br />
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|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|α-Aminoisobutyric acid<br />
<br />
|α-Aminoisobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[2-Aminoisobutyric acid|α-Aminoisobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|β-Aminoisobutyric acid<br />
<br />
|β-Aminoisobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[3-Aminoisobutyric acid|β-Aminoisobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|β-Aminobutyric acid<br />
<br />
|β-Aminobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[beta-Aminobutyric acid|β-Aminobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|γ-Aminobutyric acid<br />
<br />
|γ-Aminobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[gamma-Aminobutyric acid|γ-Aminobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Valine<br />
<br />
瓦林<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Valine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Isovaline<br />
<br />
异缬氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Isovaline]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Glutamic acid<br />
<br />
谷氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Glutamic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Norvaline<br />
<br />
诺瓦林<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Norvaline]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|α-Aminoadipic acid<br />
<br />
Α-氨基己二酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[alpha-Aminoadipic acid|α-Aminoadipic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Homoserine<br />
<br />
高丝氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Homoserine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|2-Methylserine<br />
<br />
| 2- 甲基丝氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[2-Methylserine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|β-Hydroxyaspartic acid<br />
<br />
|β-Hydroxyaspartic acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[3-Hydroxyaspartic acid|β-Hydroxyaspartic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Ornithine<br />
<br />
鸟氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Ornithine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|2-Methylglutamic acid<br />
<br />
| 2- 甲基谷氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[2-Methylglutamic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Phenylalanine<br />
<br />
| 苯丙氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Phenylalanine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Homocysteic acid<br />
<br />
高同型半胱氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Homocysteic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|S-Methylcysteine<br />
<br />
S- 甲基半胱氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[S-methylcysteine|''S''-Methylcysteine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Methionine<br />
<br />
| 蛋氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Methionine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Methionine sulfoxide<br />
<br />
蛋氨酸亚砜<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Methionine sulfoxide]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Methionine sulfone<br />
<br />
蛋氨酸砜<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Methionine sulfone]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Isoleucine<br />
<br />
异亮氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Isoleucine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Leucine<br />
<br />
亮氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Leucine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Ethionine<br />
<br />
|Ethionine<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Ethionine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Cysteine<br />
<br />
半胱氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Cysteine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Histidine<br />
<br />
| 组氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Histidine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Lysine<br />
<br />
赖氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Lysine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Asparagine<br />
<br />
天冬酰胺<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Asparagine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Pyrrolysine<br />
<br />
| 吡咯赖氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Pyrrolysine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Proline<br />
<br />
| Proline<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Proline]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Glutamine<br />
<br />
谷氨酰胺<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Glutamine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Arginine<br />
<br />
精氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Arginine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Threonine<br />
<br />
苏氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Threonine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Selenocysteine<br />
<br />
硒代半胱氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Selenocysteine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Tryptophan<br />
<br />
色氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Tryptophan]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Tyrosine<br />
<br />
| 酪氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Tyrosine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|}<br />
<br />
|}<br />
<br />
| {{na}}<br />
<br />
| {{yes}}<br />
<br />
|}<br />
<br />
<br />
<br />
==References参考==<br />
<br />
{{Reflist|30em}}<br />
<br />
<br />
<br />
==External links外部链接==<br />
<br />
*[http://millerureyexperiment.com A simulation of the Miller–Urey Experiment along with a video Interview with Stanley Miller] by Scott Ellis from CalSpace (UCSD)<br />
<br />
* [https://web.archive.org/web/20081019122408/http://www.pubs.acs.org/cen/news/86/i42/8642notw4.html Origin-Of-Life Chemistry Revisited: Reanalysis of famous spark-discharge experiments reveals a richer collection of amino acids were formed.] <br />
<br />
* [https://web.archive.org/web/20090821213017/http://www.chem.duke.edu/~jds/cruise_chem/Exobiology/miller.html Miller–Urey experiment explained]<br />
<br />
* [http://www.althofer.de/miller-experiment-with-lego.html Miller experiment with Lego bricks]<br />
<br />
*[https://www.pbs.org/exploringspace/meteorites/murchison/page5.html "Stanley Miller's Experiment: Sparking the Building Blocks of Life" on PBS]<br />
<br />
*[http://www.millerureyexperiment.com/ The Miller-Urey experiment website]<br />
<br />
*{{cite journal|doi=10.1016/0022-5193(66)90178-0|pmid=5964688|title=The origin of life and the nature of the primitive gene|journal=Journal of Theoretical Biology|volume=10|issue=1|pages=53–88|year=1966|last1=Cairns-Smith|first1=A.G.}}<br />
<br />
*[http://astrobiology.gsfc.nasa.gov/analytical/PDF/Johnsonetal2008.pdf Details of 2008 re-analysis]<br />
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<small>This page was moved from [[wikipedia:en:Miller–Urey experiment]]. Its edit history can be viewed at [[米勒-尤里实验/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%B1%B3%E5%8B%92-%E5%B0%A4%E9%87%8C%E5%AE%9E%E9%AA%8C&diff=18466米勒-尤里实验2020-11-16T09:27:18Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Chemical experiment that simulated conditions on the early Earth and tested the origin of life}}<br />
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[[File:MUexperiment.png|thumb|upright=1.5|The experiment]]<br />
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The experiment<br />
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实验<br />
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The '''Miller–Urey experiment'''<ref>{{cite journal |vauthors=Hill HG, Nuth JA |title=The catalytic potential of cosmic dust: implications for prebiotic chemistry in the solar nebula and other protoplanetary systems |journal=Astrobiology |volume=3 |issue=2 |pages=291–304 |year=2003 |pmid=14577878 |doi=10.1089/153110703769016389|bibcode = 2003AsBio...3..291H}}</ref> (or '''Miller experiment''')<ref>{{cite journal | title=The analysis of comet mass spectrometric data |author1=Balm SP |author2=Hare J.P. |author3=Kroto HW | journal=Space Science Reviews| year=1991| volume=56|issue=1–2 | pages=185–9 |doi=10.1007/BF00178408 | bibcode=1991SSRv...56..185B|url=https://www.semanticscholar.org/paper/9bce3627fcb31bac372e6610472e59008703ec4b }}</ref> was a chemical [[experiment]] that simulated the conditions thought at the time (1952) to be present on the [[early Earth]] and tested the [[abiogenesis|chemical origin of life]] under those conditions. The experiment at the time supported [[Alexander Oparin]]'s and [[J. B. S. Haldane]]'s hypothesis that putative conditions on the primitive Earth favoured chemical reactions that synthesized more complex [[organic compound]]s from simpler inorganic precursors. Considered to be the classic experiment investigating [[abiogenesis]], it was performed in 1952 by [[Stanley Miller]], supervised by [[Harold Urey]] at the [[University of Chicago]], and published the following year.<ref name=miller1953>{{cite journal |last=Miller |first=Stanley L. |url=http://www.abenteuer-universum.de/pdf/miller_1953.pdf |title=Production of Amino Acids Under Possible Primitive Earth Conditions |journal=[[Science (journal)|Science]] |year=1953 |volume=117 |pages=528–9 |doi=10.1126/science.117.3046.528 |pmid=13056598 |issue=3046 |bibcode=1953Sci...117..528M |url-status=dead |archiveurl=https://web.archive.org/web/20120317062622/http://www.abenteuer-universum.de/pdf/miller_1953.pdf |archivedate=2012-03-17 |access-date=2011-01-17 }}</ref><ref>{{cite journal |last=Miller |first=Stanley L. |author2=Harold C. Urey |title=Organic Compound Synthesis on the Primitive Earth |journal=[[Science (journal)|Science]] |year=1959 |volume=130 |pages=245–51 |doi=10.1126/science.130.3370.245 |pmid=13668555 |issue=3370|bibcode = 1959Sci...130..245M}} Miller states that he made "A more complete analysis of the products" in the 1953 experiment, listing additional results.</ref><ref>{{cite journal |title=The 1953 Stanley L. Miller Experiment: Fifty Years of Prebiotic Organic Chemistry |author1=A. Lazcano |author2=J. L. Bada |journal=Origins of Life and Evolution of Biospheres |volume=33 |year=2004 |pages=235–242 |doi=10.1023/A:1024807125069 |pmid=14515862 |issue=3|url=https://www.semanticscholar.org/paper/beda7cb912470cec6e1bf2d13535edeedf6c5b16 |bibcode=2003OLEB...33..235L }}</ref><br />
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The Miller–Urey experiment (or Miller experiment) was a chemical experiment that simulated the conditions thought at the time (1952) to be present on the early Earth and tested the chemical origin of life under those conditions. The experiment at the time supported Alexander Oparin's and J. B. S. Haldane's hypothesis that putative conditions on the primitive Earth favoured chemical reactions that synthesized more complex organic compounds from simpler inorganic precursors. Considered to be the classic experiment investigating abiogenesis, it was performed in 1952 by Stanley Miller, supervised by Harold Urey at the University of Chicago, and published the following year.<br />
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<font color="#ff8000"> 米勒尤里实验 Miller–Urey experiment</font>(或称 Miller 实验)是一个化学实验,模拟了当时(1952年)认为存在于早期地球上的条件,并在这些条件下测试了生命的化学起源。当时的实验支持了亚历山大·奥帕林和J·B·s·霍尔丹的假设,即原始地球上假定的条件有利于化学反应,即从简单的无机前体合成更复杂的有机化合物。它被认为是研究自然发生的经典实验,1952年由斯坦利·米勒完成,由芝加哥大学的哈罗德·尤里监督,并于次年出版。<br />
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After Miller's death in 2007, scientists examining sealed vials preserved from the original experiments were able to show that there were actually well over 20 different [[amino acid]]s produced in Miller's original experiments. That is considerably more than what Miller originally reported, and more than the 20 that naturally occur in the genetic code.<ref name="BBC"/> More recent evidence suggests that Earth's original atmosphere might have had a composition different from the gas used in the Miller experiment, but prebiotic experiments continue to produce [[racemic mixture]]s of simple-to-complex compounds under varying conditions.<ref name=bada2013>{{cite journal|last1=Bada|first1=Jeffrey L.|title=New insights into prebiotic chemistry from Stanley Miller's spark discharge experiments|journal=Chemical Society Reviews|year=2013|volume=42|issue=5|pages=2186–96|doi=10.1039/c3cs35433d|pmid=23340907|url=https://semanticscholar.org/paper/6f463e8a3611fa7f25c143991dfddac49c396b73}}</ref><br />
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After Miller's death in 2007, scientists examining sealed vials preserved from the original experiments were able to show that there were actually well over 20 different amino acids produced in Miller's original experiments. That is considerably more than what Miller originally reported, and more than the 20 that naturally occur in the genetic code.<br />
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2007年米勒去世后,科学家们检查了从原始实验中保存下来的密封小瓶,发现实际上米勒原始实验中产生了超过20种不同的氨基酸。这大大超过了米勒最初报道的数量,也超过了遗传密码中自然产生的20种。<br />
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== Experiment实验 ==<br />
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[[File:Miller-Urey experiment - Work by the C3BC consortium, licensed under CC-BY-3.0.webm|thumb|Descriptive video of the experiment]]<br />
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Descriptive video of the experiment<br />
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实验的描述性视频<br />
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The experiment used [[water]] (H<sub>2</sub>O), [[methane]] (CH<sub>4</sub>), [[ammonia]] (NH<sub>3</sub>), and [[hydrogen]] (H<sub>2</sub>). The chemicals were all sealed inside a sterile 5-liter glass flask connected to a 500 ml flask half-full of water. The water in the smaller flask was heated to induce [[evaporation]], and the water vapour was allowed to enter the larger flask. Continuous electrical sparks were fired between the electrodes to simulate [[lightning]] in the water vapour and gaseous mixture, and then the simulated atmosphere was cooled again so that the water condensed and trickled into a U-shaped trap at the bottom of the apparatus.<br />
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The experiment used water (H<sub>2</sub>O), methane (CH<sub>4</sub>), ammonia (NH<sub>3</sub>), and hydrogen (H<sub>2</sub>). The chemicals were all sealed inside a sterile 5-liter glass flask connected to a 500 ml flask half-full of water. The water in the smaller flask was heated to induce evaporation, and the water vapour was allowed to enter the larger flask. Continuous electrical sparks were fired between the electrodes to simulate lightning in the water vapour and gaseous mixture, and then the simulated atmosphere was cooled again so that the water condensed and trickled into a U-shaped trap at the bottom of the apparatus.<br />
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实验用水(H2O)、甲烷(CH4)、氨(NH3)和氢(H 2)。所有的化学物质都被密封在一个5升的无菌玻璃瓶里,这个玻璃瓶连接着一个500毫升的半满水的烧瓶。将小烧瓶中的水加热以诱导蒸发,使水蒸气进入大烧瓶。在电极之间连续地点燃电火花,以模拟水蒸气和气体混合物中的闪电,然后再次冷却模拟的大气,使水凝结并滴入装置底部的U形阱中。<br />
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After a day, the solution collected at the trap had turned pink in colour, and after a week of continuous operation the solution was deep red and turbid.<ref name=miller1953/> The boiling flask was then removed, and mercuric chloride was added to prevent microbial contamination. The reaction was stopped by adding barium hydroxide and sulfuric acid, and evaporated to remove impurities. Using [[paper chromatography]], Miller identified five amino acids present in the solution: [[glycine]], [[alanine|α-alanine]] and [[beta-Alanine|β-alanine]] were positively identified, while [[aspartic acid]] and [[alpha-Aminobutyric acid|α-aminobutyric acid]] (AABA) were less certain, due to the spots being faint.<ref name=miller1953/><br />
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After a day, the solution collected at the trap had turned pink in colour, and after a week of continuous operation the solution was deep red and turbid.<br />
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一天之后,在诱捕器上收集到的溶液变成了粉红色,连续操作一周之后,溶液变成了深红色和混浊的液体。<br />
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In a 1996 interview, Stanley Miller recollected his lifelong experiments following his original work and stated: "Just turning on the spark in a basic pre-biotic experiment will yield 11 out of 20 amino acids."<ref>{{cite web|url=http://www.accessexcellence.org/WN/NM/miller.php |title=Exobiology: An Interview with Stanley L. Miller |publisher=Accessexcellence.org |archiveurl=https://web.archive.org/web/20080518054852/http://www.accessexcellence.org/WN/NM/miller.php |archivedate=May 18, 2008 |accessdate=2009-08-20}}</ref><br />
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The original experiment remained in 2017 under the care of Miller and Urey's former student Jeffrey Bada, a professor at the UCSD, Scripps Institution of Oceanography. , the apparatus used to conduct the experiment was on display at the Denver Museum of Nature and Science.<br />
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最初的实验在2017年由 Miller 和 Urey以前的学生 Jeffrey Bada 负责,他是加州大学圣地亚哥分校斯克里普斯海洋研究所的教授。实验仪器在丹佛自然科学博物馆展出。<br />
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The original experiment remained in 2017 under the care of Miller and Urey's former student [[Jeffrey Bada]], a professor at the [[University of California, San Diego|UCSD]], [[Scripps Institution of Oceanography]].<ref>{{cite news |url=https://www.nytimes.com/2010/05/18/science/18conv.html |title=A Conversation With Jeffrey L. Bada: A Marine Chemist Studies How Life Began |newspaper=nytimes.com |date=2010-05-17 |first=Claudia |last=Dreifus |authorlink=Claudia Dreifus |url-status=live |archiveurl=https://web.archive.org/web/20170118034218/http://www.nytimes.com/2010/05/18/science/18conv.html |archivedate=2017-01-18 }}</ref> {{asof|2013}}, the apparatus used to conduct the experiment was on display at the [[Denver Museum of Nature and Science]].<ref>{{cite news|url=http://www.dmns.org/science/museum-scientists/david-grinspoon/funky-science-wonder-lab/research-updates/astrobiology-collection-miller-urey-apparatus | title=Astrobiology Collection: Miller-Urey Apparatus |archiveurl=https://web.archive.org/web/20130524090309/http://www.dmns.org/science/museum-scientists/david-grinspoon/funky-science-wonder-lab/research-updates/astrobiology-collection-miller-urey-apparatus/ |archivedate=2013-05-24 |publisher=Denver Museum of Nature & Science }}</ref>{{update after|2020|4|14}}<br />
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One-step reactions among the mixture components can produce hydrogen cyanide (HCN), formaldehyde (CH<sub>2</sub>O), and other active intermediate compounds (acetylene, cyanoacetylene, etc.):<br />
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混合组分之间的一步反应可以生成氰化氢、甲醛和其他活性中间体化合物(乙炔、氰乙炔等):<br />
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==Chemistry of experiment实验化学==<br />
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One-step reactions among the mixture components can produce [[hydrogen cyanide]] (HCN), [[formaldehyde]] (CH<sub>2</sub>O),<ref>https://www.webcitation.org/query?url=http://www.geocities.com/capecanaveral/lab/2948/orgel.html&date=2009-10-25+16:53:26 Origin of Life on Earth by Leslie E. Orgel</ref><ref>{{Cite book |url=http://books.nap.edu/openbook.php?record_id=11860&page=85 |title=Read "Exploring Organic Environments in the Solar System" at NAP.edu |accessdate=2008-10-25 |url-status=live |archiveurl=https://web.archive.org/web/20090621053626/http://books.nap.edu/openbook.php?record_id=11860&page=85 |archivedate=2009-06-21 |doi=10.17226/11860 |year=2007 |isbn=978-0-309-10235-3 |last1=Council |first1=National Research |last2=Studies |first2=Division on Earth Life |last3=Technology |first3=Board on Chemical Sciences and |last4=Sciences |first4=Division on Engineering Physical |last5=Board |first5=Space Studies |last6=System |first6=Task Group on Organic Environments in the Solar }} Exploring Organic Environments in the Solar System (2007)</ref> and other active intermediate compounds ([[acetylene]], [[cyanoacetylene]], etc.):{{Citation needed|date=June 2016}}<br />
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CO<sub>2</sub> &rarr; CO + [O] (atomic oxygen)<br />
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CO < sub > 2 </sub > & rarr; CO + [ o ](原子氧) <br />
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CH<sub>4</sub> + 2[O] &rarr; CH<sub>2</sub>O + H<sub>2</sub>O<br />
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CH < sub > 4 </sub > + 2[ o ] & rarr; CH < sub > 2 </sub > o + h < sub > 2 </sub > o<br />
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: CO<sub>2</sub> &rarr; CO + [O] (atomic oxygen)<br />
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CO + NH<sub>3</sub> &rarr; HCN + H<sub>2</sub>O<br />
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CO + NH < sub > 3 </sub > & rarr; HCN + h < sub > 2 </sub > o<br />
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: CH<sub>4</sub> + 2[O] &rarr; CH<sub>2</sub>O + H<sub>2</sub>O<br />
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CH<sub>4</sub> + NH<sub>3</sub> &rarr; HCN + 3H<sub>2</sub> (BMA process)<br />
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CH<sub>4</sub> + NH<sub>3</sub> &rarr; HCN + 3H<sub>2</sub> (BMA process)<br />
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: CO + NH<sub>3</sub> &rarr; HCN + H<sub>2</sub>O<br />
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: CH<sub>4</sub> + NH<sub>3</sub> &rarr; HCN + 3H<sub>2</sub> ([[BMA process]])<br />
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The formaldehyde, ammonia, and HCN then react by Strecker synthesis to form amino acids and other biomolecules:<br />
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然后,甲醛、氨和 HCN 通过 Strecker合成反应生成氨基酸和其他生物分子:<br />
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The formaldehyde, ammonia, and HCN then react by [[Strecker synthesis]] to form amino acids and other biomolecules:<br />
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CH<sub>2</sub>O + HCN + NH<sub>3</sub> &rarr; NH<sub>2</sub>-CH<sub>2</sub>-CN + H<sub>2</sub>O<br />
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CH<sub>2</sub>O + HCN + NH<sub>3</sub> &rarr; NH<sub>2</sub>-CH<sub>2</sub>-CN + H<sub>2</sub>O<br />
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NH<sub>2</sub>-CH<sub>2</sub>-CN + 2H<sub>2</sub>O &rarr; NH<sub>3</sub> + NH<sub>2</sub>-CH<sub>2</sub>-COOH (glycine)<br />
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NH<sub>2</sub>-CH<sub>2</sub>-CN + 2H<sub>2</sub>O &rarr; NH<sub>3</sub> + NH<sub>2</sub>-CH<sub>2</sub>-COOH (glycine)<br />
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: CH<sub>2</sub>O + HCN + NH<sub>3</sub> &rarr; NH<sub>2</sub>-CH<sub>2</sub>-CN + H<sub>2</sub>O<br />
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: NH<sub>2</sub>-CH<sub>2</sub>-CN + 2H<sub>2</sub>O &rarr; NH<sub>3</sub> + NH<sub>2</sub>-CH<sub>2</sub>-COOH ([[glycine]])<br />
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Furthermore, water and formaldehyde can react, via Butlerov's reaction to produce various sugars like ribose.<br />
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此外,水和甲醛可以反应,通过巴特列罗夫的反应产生各种糖,如核糖。<br />
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Furthermore, water and formaldehyde can react, via [[Formose reaction|Butlerov's reaction]] to produce various [[sugar]]s like [[ribose]].<br />
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The experiments showed that simple organic compounds of building blocks of proteins and other macromolecules can be formed from gases with the addition of energy.<br />
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实验表明,在添加能量的情况下,气体可以形成简单的有机化合物,由蛋白质和其他大分子组成 。<br />
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The experiments showed that simple organic compounds of building blocks of proteins and other macromolecules can be formed from gases with the addition of energy.<br />
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This experiment inspired many others. In 1961, Joan Oró found that the nucleotide base adenine could be made from hydrogen cyanide (HCN) and ammonia in a water solution. His experiment produced a large amount of adenine, the molecules of which were formed from 5 molecules of HCN. <br />
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这个实验启发了许多其他人。1961年,琼·奥雷奥发现,在水溶液中,由氰化氢和氨制成的核苷酸碱基腺嘌呤。他的实验产生了大量的腺嘌呤,其分子由5个HCN分子组成。<br />
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==Other experiments其他实验==<br />
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Also, many amino acids are formed from HCN and ammonia under these conditions. <br />
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此外,许多氨基酸是由 HCN 和氨在这些条件下形成。<br />
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This experiment inspired many others. In 1961, [[Joan Oró]] found that the [[nucleotide]] base [[adenine]] could be made from [[hydrogen cyanide]] (HCN) and [[ammonia]] in a water solution. His experiment produced a large amount of adenine, the molecules of which were formed from 5 molecules of HCN.<ref>{{cite journal |vauthors=Oró J, Kimball AP |title=Synthesis of purines under possible primitive earth conditions. I. Adenine from hydrogen cyanide |journal=Archives of Biochemistry and Biophysics |volume=94|issue=2 |pages=217–27 |date=August 1961 |pmid=13731263 |doi=10.1016/0003-9861(61)90033-9}}</ref> <br />
这个实验启发了许多其他人。1961年,[[Joan Oró]]发现[[核苷酸]]碱基[[腺嘌呤]]可以由[[氰化氢]](HCN)和[[氨]]在水溶液中制成。他的实验产生了大量腺嘌呤,腺嘌呤分子由5个HCN分子组成。 <br />
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Experiments conducted later showed that the other RNA and DNA nucleobases could be obtained through simulated prebiotic chemistry with a reducing atmosphere.<br />
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后来进行的实验表明,其他 RNA 和 DNA 碱基可以通过模拟生命前化学在还原气氛下获得。<br />
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Also, many amino acids are formed from HCN and ammonia under these conditions.<ref>{{cite journal |vauthors=Oró J, Kamat SS |title=Amino-acid synthesis from hydrogen cyanide under possible primitive earth conditions |journal=Nature |volume=190 |issue= 4774|pages=442–3 |date=April 1961 |pmid=13731262 |doi=10.1038/190442a0|bibcode = 1961Natur.190..442O |url=https://www.semanticscholar.org/paper/1aea2775f328d439e5bb65e61fdf3b988d829052 }}</ref> <br />
此外,在这些条件下,许多氨基酸由HCN和氨形成 <br />
Experiments conducted later showed that the other [[Nucleobase|RNA and DNA nucleobases]] could be obtained through simulated prebiotic chemistry with a [[reducing atmosphere]].<ref>{{cite book | title=Origins of Prebiological Systems and of Their Molecular Matrices| editor= Fox SW| author=Oró J| year=1967| pages=137| publisher=New York Academic Press}}</ref><br />
随后进行的实验表明,另一种[[核碱基| RNA和DNA碱基]]可以通过模拟益生元化学和[[还原气氛]]获得 <br />
There also had been similar electric discharge experiments related to the origin of life contemporaneous with Miller–Urey. An article in The New York Times (March 8, 1953:E9), titled "Looking Back Two Billion Years" describes the work of Wollman (William) M. MacNevin at The Ohio State University, before the Miller Science paper was published in May 1953. MacNevin was passing 100,000 volt sparks through methane and water vapor and produced "resinous solids" that were "too complex for analysis." The article describes other early earth experiments being done by MacNevin. It is not clear if he ever published any of these results in the primary scientific literature.<!--is it not clear because academics have researched this and somehow can't tell, or is it just not clear to the Wikipedia contributor from reading only the NYT article?--><br />
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与米勒-尤里同时期也有过类似的与生命起源有关的放电实验。《纽约时报》(1953年3月8日:E9)上的一篇题为“回顾20亿年”的文章描述了1953年5月米勒科学论文发表之前,俄亥俄州立大学的沃尔曼(William)M.MacNevin的工作。麦克尼文通过甲烷和水蒸气产生10万伏特的火花,产生“树脂固体”,这些“树脂固体”过于复杂,无法分析。目前还不清楚他是否曾在原始科学文献中发表过这些结果。(不清楚是因为学者们已经对此进行了研究,不知何故无法判断,还是仅仅因为阅读了《纽约时报》的文章,维基百科的撰稿人就不清楚了?) <br />
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There also had been similar electric discharge experiments related to the [[origin of life]] contemporaneous with Miller–Urey. An article in ''[[The New York Times]]'' (March 8, 1953:E9), titled "Looking Back Two Billion Years" describes the work of Wollman (William) M. MacNevin at [[The Ohio State University]], before the Miller ''Science'' paper was published in May 1953. MacNevin was passing 100,000 volt sparks through methane and water vapor and produced "resinous solids" that were "too complex for analysis." The article describes other early earth experiments being done by MacNevin. It is not clear if he ever published any of these results in the primary scientific literature.<ref>{{cite book | title=History of Shock Waves, Explosions and Impact: A Chronological and Biographical Reference | publisher=[[Springer-Verlag]] | author=Krehl, Peter O. K. | year=2009 | pages=603}}</ref><!--is it not clear because academics have researched this and somehow can't tell, or is it just not clear to the Wikipedia contributor from reading only the NYT article?--><br />
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K. A. Wilde submitted a paper to Science on December 15, 1952, before Miller submitted his paper to the same journal on February 10, 1953. Wilde's paper was published on July 10, 1953. Wilde used voltages up to only 600 V on a binary mixture of carbon dioxide (CO<sub>2</sub>) and water in a flow system. He observed only small amounts of carbon dioxide reduction to carbon monoxide, and no other significant reduction products or newly formed carbon compounds.<br />
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1952年12月15日,K·A· 王尔德向《科学》杂志提交了一篇论文,之后米勒又于1953年2月10日向同一杂志提交了他的论文。王尔德的论文发表于1953年7月10日。王尔德使用的电压只有600v 对二氧化碳(CO2)和流动系统中的水的二元混合物。他观察到只有少量的二氧化碳减少为一氧化碳,没有其他重要的还原产物或新形成的碳化合物。<br />
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Other researchers were studying UV-photolysis of water vapor with carbon monoxide. They have found that various alcohols, aldehydes and organic acids were synthesized in reaction mixture.<br />
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其他研究人员正在研究水蒸气与一氧化碳的紫外光解反应。他们发现各种醇类、醛类和有机酸都是在反应混合物中合成的。<br />
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K. A. Wilde submitted a paper to ''Science'' on December 15, 1952, before Miller submitted his paper to the same journal on February 10, 1953. Wilde's paper was published on July 10, 1953.<ref>{{cite journal |last=Wilde |first=Kenneth A. |authorlink= |first2=Bruno J. |last2=Zwolinski |first3=Ransom B. |last3=Parlin |date=July 1953 |title=The Reaction Occurring in CO<sub>2</sub>, <sub>2</sub>O Mixtures in a High-Frequency Electric Arc |journal=[[Science (journal)|Science]] |volume=118 |issue=3054 |pages=43–44 |id= |doi=10.1126/science.118.3054.43-a |pmid=13076175 |bibcode=1953Sci...118...43W |df= }}</ref> Wilde used voltages up to only 600 V on a binary mixture of [[carbon dioxide]] (CO<sub>2</sub>) and water in a flow system. He observed only small amounts of carbon dioxide reduction to carbon monoxide, and no other significant reduction products or newly formed carbon compounds.<br />
1952年12月15日,王尔德向《科学》杂志提交了一篇论文,米勒在1953年2月10日向同一家杂志提交了他的论文。王尔德的论文发表于1953年7月10日。[17]王尔德在一个流动系统中使用了高达600V的二氧化碳(CO2)和水的二元混合物。他观察到只有少量二氧化碳还原成一氧化碳,没有其他显著的还原产物或新形成的碳化合物<br />
Other researchers were studying [[Ultraviolet|UV]]-[[photolysis]] of water vapor with [[carbon monoxide]]. They have found that various alcohols, aldehydes and organic acids were synthesized in reaction mixture.<ref>[https://doi.org/10.1007%2FBF00931407 Synthesis of organic compounds from carbon monoxide and water by UV photolysis] ''Origins of Life''. December 1978, Volume 9, Issue 2, pp 93-101<br />
其他研究人员正在研究水蒸气与[[一氧化碳]]的[[紫外线|紫外线]]-[[光解]]。他们发现在反应混合物中可以合成各种醇、醛和有机酸 <br />
More recent experiments by chemists Jeffrey Bada, one of Miller's graduate students, and Jim Cleaves at Scripps Institution of Oceanography of the University of California, San Diego were similar to those performed by Miller. However, Bada noted that in current models of early Earth conditions, carbon dioxide and nitrogen (N<sub>2</sub>) create nitrites, which destroy amino acids as fast as they form. <!--However, the early Earth may have had significant amounts of iron and carbonate minerals able to neutralize the effects of the nitrites. --> <!-- Please find a scientific paper that makes this statement before removing the tag -- and then the remark may be visible again --> When Bada performed the Miller-type experiment with the addition of iron and carbonate minerals, the products were rich in amino acids. This suggests the origin of significant amounts of amino acids may have occurred on Earth even with an atmosphere containing carbon dioxide and nitrogen.<br />
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米勒的研究生之一、化学家杰弗里·巴达和加州大学圣地亚哥斯克里普斯海洋学研究所的吉姆·克里夫斯最近的实验与米勒的实验相似。然而,Bada指出,在目前的早期地球条件模型中,二氧化碳和氮(N2)会产生亚硝酸盐,亚硝酸盐在氨基酸形成的同时也会被破坏。<!--然而,早期地球可能有大量的铁和碳酸盐矿物能够中和亚硝酸盐的影响。--> <!--在去掉标签之前,请先找到一篇科学论文来说明这一点——然后这句话可能会再次显现出来——当Bada进行米勒式实验,添加铁和碳酸盐矿物时,产品富含氨基酸。这表明,即使在含有二氧化碳和氮气的大气中,也可能有大量氨基酸的起源。 <br />
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Akiva Bar-nun, Hyman Hartman.</ref><br />
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More recent experiments by chemists Jeffrey Bada, one of Miller's graduate students, and Jim Cleaves at [[Scripps Institution of Oceanography]] of the [[University of California, San Diego]] were similar to those performed by Miller. However, Bada noted that in current models of early Earth conditions, carbon dioxide and [[nitrogen]] (N<sub>2</sub>) create [[nitrite]]s, which destroy amino acids as fast as they form. <!--However, the early Earth may have had significant amounts of iron and [[carbonate minerals]] able to neutralize the effects of the nitrites.{{Citation needed|date=January 2016}} --> <!-- Please find a scientific paper that makes this statement before removing the tag -- and then the remark may be visible again --> When Bada performed the Miller-type experiment with the addition of iron and carbonate minerals, the products were rich in amino acids. This suggests the origin of significant amounts of amino acids may have occurred on Earth even with an atmosphere containing carbon dioxide and nitrogen.<ref name=Fox>{{Cite news |last=Fox |first=Douglas |date=2007-03-28 |title=Primordial Soup's On: Scientists Repeat Evolution's Most Famous Experiment |periodical=Scientific American |series=History of Science |publisher=Scientific American Inc. |url=http://www.sciam.com/article.cfm?id=primordial-soup-urey-miller-evolution-experiment-repeated |accessdate=2008-07-09 }}<br>{{Cite journal | last1 = Cleaves | first1 = H. J. | last2 = Chalmers | first2 = J. H. | last3 = Lazcano | first3 = A. | last4 = Miller | first4 = S. L. | last5 = Bada | first5 = J. L. | title = A Reassessment of Prebiotic Organic Synthesis in Neutral Planetary Atmospheres | doi = 10.1007/s11084-007-9120-3 | journal = Origins of Life and Evolution of Biospheres | volume = 38 | issue = 2 | pages = 105–115 | year = 2008 | pmid = 18204914| bibcode = 2008OLEB...38..105C |url=http://www.astro.ulg.ac.be/~mouchet/BIOC0701-1/Cleaves-etal-2008.pdf |url-status=dead |archive-url=https://web.archive.org/web/20131107134729/http://www.astro.ulg.ac.be/~mouchet/BIOC0701-1/Cleaves-etal-2008.pdf |archive-date=2013-11-07 }}</ref><br />
米勒的研究生之一、化学家杰弗里·巴达和加州大学圣地亚哥斯克里普斯海洋学研究所的吉姆·克里夫斯最近的实验与米勒的实验相似。然而,巴达指出,在目前的早期地球条件模型中,二氧化碳和氮气(N2)产生亚硝酸盐,亚硝酸盐在氨基酸形成的同时就被破坏。Bada在进行Miller型实验时添加了铁和碳酸盐矿物,产物富含氨基酸。这表明,即使在含有二氧化碳和氮气的大气中,也可能有大量氨基酸的起源 <br />
Some evidence suggests that Earth's original atmosphere might have contained fewer of the reducing molecules than was thought at the time of the Miller–Urey experiment. There is abundant evidence of major volcanic eruptions 4 billion years ago, which would have released carbon dioxide, nitrogen, hydrogen sulfide (H<sub>2</sub>S), and sulfur dioxide (SO<sub>2</sub>) into the atmosphere. Experiments using these gases in addition to the ones in the original Miller–Urey experiment have produced more diverse molecules. The experiment created a mixture that was racemic (containing both L and D enantiomers) and experiments since have shown that "in the lab the two versions are equally likely to appear"; however, in nature, L amino acids dominate. Later experiments have confirmed disproportionate amounts of L or D oriented enantiomers are possible.<br />
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一些证据表明,地球原始大气层中还原分子的含量可能比 Miller-Urey 实验时所认为的要少。有大量的证据表明,40亿年前的大型火山爆发会向大气中释放二氧化碳、氮、硫化氢(H2S)和二氧化硫(SO2)。除了最初的 Miller-Urey 实验中使用的气体之外,使用这些气体的实验已经产生了更多样化的分子。该实验创造了一种外消旋体(包含L和D对映体)的混合物,此后的实验表明,“在实验室中,这两种化合物出现的可能性相等” ; 然而,在自然界中,l 氨基酸占主导地位。后来的实验证实了不成比例的L或D取向对映异构体是可能的。<br />
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==Earth's early atmosphere地球最早的大气层==<br />
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Originally it was thought that the primitive secondary atmosphere contained mostly ammonia and methane. However, it is likely that most of the atmospheric carbon was CO<sub>2</sub> with perhaps some CO and the nitrogen mostly N<sub>2</sub>. In practice gas mixtures containing CO, CO<sub>2</sub>, N<sub>2</sub>, etc. give much the same products as those containing CH<sub>4</sub> and NH<sub>3</sub> so long as there is no O<sub>2</sub>. The hydrogen atoms come mostly from water vapor. In fact, in order to generate aromatic amino acids under primitive earth conditions it is necessary to use less hydrogen-rich gaseous mixtures. Most of the natural amino acids, hydroxyacids, purines, pyrimidines, and sugars have been made in variants of the Miller experiment.<br />
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起初人们认为原始的二次大气主要含有氨和甲烷。但是,大气中的大部分碳可能是 CO2 ,也可能是一些 CO 和氮大部分是N2 。在实际应用中,含有 CO、 CO2 、 N2 等的混合气体。只要没有O 2 ,就可以给出与含 CH4和 NH3 相同的产品。氢原子主要来自水蒸气。事实上,为了在原始土壤条件下生成芳香族氨基酸,必须使用较少的富氢气体混合物。大多数天然氨基酸、羟基酸、嘌呤、嘧啶和糖都是米勒实验的变体。<br />
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Some evidence suggests that Earth's original atmosphere might have contained fewer of the reducing molecules than was thought at the time of the Miller–Urey experiment. There is abundant evidence of major volcanic eruptions 4 billion years ago, which would have released carbon dioxide, nitrogen, [[hydrogen sulfide]] (H<sub>2</sub>S), and [[sulfur dioxide]] (SO<sub>2</sub>) into the atmosphere.<ref name=Green>{{Cite journal|last=Green|first=Jack|title=Academic Aspects of Lunar Water Resources and Their Relevance to Lunar Protolife|journal=International Journal of Molecular Sciences|year=2011|volume=12|issue=9|pages=6051–6076|doi=10.3390/ijms12096051|pmid=22016644|pmc=3189768|ref=harv}}</ref> Experiments using these gases in addition to the ones in the original Miller–Urey experiment have produced more diverse molecules. The experiment created a mixture that was racemic (containing both L and D [[enantiomer]]s) and experiments since have shown that "in the lab the two versions are equally likely to appear";<ref name="NS">{{Cite news |date=2006-06-02 |title=Right-handed amino acids were left behind |periodical=[[New Scientist]] |publisher=Reed Business Information Ltd |issue=2554 |pages=18 |url=https://www.newscientist.com/channel/life/mg19025545.200-righthanded-amino-acids-were-left-behind.html |accessdate=2008-07-09 |url-status=live |archiveurl=https://web.archive.org/web/20081024211531/http://www.newscientist.com/channel/life/mg19025545.200-righthanded-amino-acids-were-left-behind.html |archivedate=2008-10-24 }}</ref> however, in nature, L amino acids dominate. Later experiments have confirmed disproportionate amounts of L or D oriented enantiomers are possible.<ref>{{cite journal |last=Kojo |first=Shosuke |first2=Hiromi |last2=Uchino |first3=Mayu |last3=Yoshimura |first4=Kyoko |last4=Tanaka |date=October 2004 |title=Racemic D,L-asparagine causes enantiomeric excess of other coexisting racemic D,L-amino acids during recrystallization: a hypothesis accounting for the origin of L-amino acids in the biosphere |journal=Chemical Communications |volume= |issue=19 |pages=2146–2147 |pmid=15467844 |doi=10.1039/b409941a}}</ref><br />
一些证据表明,地球原始大气中含有的还原分子可能比米勒-尤里实验时所认为的要少。有大量证据表明,40亿年前的大型火山喷发会向大气中释放二氧化碳、氮气、硫化氢(H2S)和二氧化硫(SO2)。[20]除了最初米勒-尤里(Miller-Urey)实验中的实验外,使用这些气体的实验产生了更多不同的分子。实验产生了一种外消旋的混合物(同时含有L和D对映体),此后的实验表明,“在实验室中,两种对映体出现的可能性相等”;然而,在自然界中,L氨基酸占主导地位。后来的实验证实了不相称数量的L或D取向的对映体是可能的。 <br />
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More recent results may question these conclusions. The University of Waterloo and University of Colorado conducted simulations in 2005 that indicated that the early atmosphere of Earth could have contained up to 40 percent hydrogen—implying a much more hospitable environment for the formation of prebiotic organic molecules. The escape of hydrogen from Earth's atmosphere into space may have occurred at only one percent of the rate previously believed based on revised estimates of the upper atmosphere's temperature. One of the authors, Owen Toon notes: "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept... I think this study makes the experiments by Miller and others relevant again." Outgassing calculations using a chondritic model for the early earth complement the Waterloo/Colorado results in re-establishing the importance of the Miller–Urey experiment.<br />
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最近的研究结果可能会质疑这些结论。滑铁卢大学和科罗拉多大学在2005年进行了模拟,结果表明地球早期大气中可能含有高达40%的氢,这意味着有利于形成益生元有机分子的环境更加有利。氢从地球大气层逃逸到太空的速度可能只有先前根据对高层大气温度的修正估计所相信的速率的百分之一。作者之一欧文·图恩指出:“在这个新的场景中,有机物可以在早期大气中高效地产生,这让我们回到海洋中富含有机物的汤的概念。。。我认为这项研究使米勒和其他人的实验再次具有相关性。“利用早期地球的球粒陨石模型进行放气计算,补充了滑铁卢/科罗拉多的结果,重新确立了米勒-乌雷实验的重要性<br />
Originally it was thought that the primitive [[secondary atmosphere]] contained mostly ammonia and methane. However, it is likely that most of the atmospheric carbon was CO<sub>2</sub> with perhaps some CO and the nitrogen mostly N<sub>2</sub>. In practice gas mixtures containing CO, CO<sub>2</sub>, N<sub>2</sub>, etc. give much the same products as those containing CH<sub>4</sub> and NH<sub>3</sub> so long as there is no O<sub>2</sub>. The hydrogen atoms come mostly from water vapor. In fact, in order to generate aromatic amino acids under primitive earth conditions it is necessary to use less hydrogen-rich gaseous mixtures. Most of the natural amino acids, [[hydroxy acid|hydroxyacids]], purines, pyrimidines, and sugars have been made in variants of the Miller experiment.<ref name=bada2013/><ref>{{cite journal|last1=Ruiz-Mirazo|first1=Kepa|last2=Briones|first2=Carlos|last3=de la Escosura|first3=Andrés|title=Prebiotic Systems Chemistry: New Perspectives for the Origins of Life|journal=Chemical Reviews|year=2014|volume=114|issue=1|pages=285–366|doi=10.1021/cr2004844|pmid=24171674}}</ref><br />
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最初人们认为原始的二次大气主要含有氨和甲烷。然而,大气中的碳很可能大部分是二氧化碳,也许还有一些一氧化碳,氮主要是氮气。实际上,只要没有氧气,含有CO、CO2、N2等的气体混合物产生的产物与含有CH4和NH3的气体混合物的产物基本相同。氢原子主要来自水蒸气。事实上,为了在原始地球条件下产生芳香族氨基酸,有必要使用较少的富氢气体混合物。大多数天然氨基酸、羟基酸、嘌呤、嘧啶和糖都是在米勒实验的变体中制造的 <br />
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In contrast to the general notion of early earth's reducing atmosphere, researchers at the Rensselaer Polytechnic Institute in New York reported the possibility of oxygen available around 4.3 billion years ago. Their study reported in 2011 on the assessment of Hadean zircons from the earth's interior (magma) indicated the presence of oxygen traces similar to modern-day lavas. This study suggests that oxygen could have been released in the earth's atmosphere earlier than generally believed.<br />
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与早期地球还原大气层的普遍观点不同,纽约伦斯勒理工学院的研究人员在43亿年前报告了氧气的可能性。他们在2011年报告了对来自地球内部(岩浆)的哈迪恩锆石的评估研究,研究表明存在类似于现代熔岩的氧气痕迹。这项研究表明,氧气在地球大气中释放的时间可能比人们通常认为的要早。<br />
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More recent results may question these conclusions. The University of Waterloo and University of Colorado conducted simulations in 2005 that indicated that the early atmosphere of Earth could have contained up to 40 percent hydrogen—implying a much more hospitable environment for the formation of prebiotic organic molecules. The escape of hydrogen from Earth's atmosphere into space may have occurred at only one percent of the rate previously believed based on revised estimates of the upper atmosphere's temperature.<ref>{{cite web |url=http://newsrelease.uwaterloo.ca/news.php?id=4348 |accessdate=2005-12-17 |title=Early Earth atmosphere favorable to life: study |publisher=University of Waterloo |url-status=dead |archiveurl=https://web.archive.org/web/20051214230357/http://newsrelease.uwaterloo.ca/news.php?id=4348 |archivedate=2005-12-14 }}</ref> One of the authors, Owen Toon notes: "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept... I think this study makes the experiments by Miller and others relevant again." Outgassing calculations using a chondritic model for the early earth complement the Waterloo/Colorado results in re-establishing the importance of the Miller–Urey experiment.<ref>{{cite web |url=http://news-info.wustl.edu/news/page/normal/5513.html |accessdate=2005-12-17 |title=Calculations favor reducing atmosphere for early earth – Was Miller–Urey experiment correct? |first=Tony |last=Fitzpatrick |publisher=Washington University in St. Louis |year=2005 |url-status=dead |archiveurl=https://web.archive.org/web/20080720174657/http://news-info.wustl.edu/news/page/normal/5513.html |archivedate=2008-07-20 }}</ref><br />
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最近的研究结果可能会质疑这些结论。滑铁卢大学和科罗拉多大学在2005年进行了模拟,结果表明地球早期大气中可能含有高达40%的氢,这意味着有利于形成益生元有机分子的环境更加有利。氢从地球大气层逃逸到太空的速度可能只有先前根据对高层大气温度的修正估计而认为的速率的百分之一。[24]作者之一欧文·图恩指出:“在这种新的情况下,早期大气中可以有效地产生有机物,带我们回到海洋中有机丰富的汤的概念。】我认为这项研究使米勒和其他人的实验再次具有相关性。“利用早期地球的球粒陨石模型进行放气计算,补充了滑铁卢/科罗拉多州的结果,重新确立了米勒-尤里实验的重要性 <br />
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In contrast to the general notion of early earth's reducing atmosphere, researchers at the [[Rensselaer Polytechnic Institute]] in New York reported the possibility of oxygen available around 4.3 billion years ago. Their study reported in 2011 on the assessment of Hadean [[zircons]] from the earth's interior ([[magma]]) indicated the presence of oxygen traces similar to modern-day lavas.<ref>{{cite journal|last1=Trail|first1=Dustin|last2=Watson|first2=E. Bruce|last3=Tailby|first3=Nicholas D.|title=The oxidation state of Hadean magmas and implications for early Earth's atmosphere|journal=Nature|year=2011|volume=480|issue=7375|pages=79–82|doi=10.1038/nature10655|pmid=22129728|bibcode=2011Natur.480...79T|url=https://www.semanticscholar.org/paper/e87ff5db353f56ac40649b2a4ca618f3c2067cdb}}</ref> This study suggests that oxygen could have been released in the earth's atmosphere earlier than generally believed.<ref>{{cite journal|last1=Scaillet|first1=Bruno|last2=Gaillard|first2=Fabrice|title=Earth science: Redox state of early magmas|journal=Nature|date=2011|volume=480|issue=7375|pages=48–49|doi=10.1038/480048a|pmid=22129723|bibcode=2011Natur.480...48S|url=https://hal.archives-ouvertes.fr/file/index/docid/648930/filename/Scaillet-Nature2-2011.pdf|url-status=live|archiveurl=https://web.archive.org/web/20171026110646/https://hal.archives-ouvertes.fr/file/index/docid/648930/filename/Scaillet-Nature2-2011.pdf|archivedate=2017-10-26|citeseerx=10.1.1.659.2086}}</ref><br />
与早期地球大气还原的一般观念不同,纽约伦斯勒理工学院的研究人员报告说,大约43亿年前,有可能存在氧气。他们在2011年对来自地球内部(岩浆)的Hadean锆石进行评估的研究表明,存在着类似于现代熔岩的氧痕迹。这项研究表明,地球大气中的氧气可能比一般认为的更早释放。<br />
Conditions similar to those of the Miller–Urey experiments are present in other regions of the solar system, often substituting ultraviolet light for lightning as the energy source for chemical reactions. The Murchison meteorite that fell near Murchison, Victoria, Australia in 1969 was found to contain over 90 different amino acids, nineteen of which are found in Earth life. Comets and other icy outer-solar-system bodies are thought to contain large amounts of complex carbon compounds (such as tholins) formed by these processes, darkening surfaces of these bodies. The early Earth was bombarded heavily by comets, possibly providing a large supply of complex organic molecules along with the water and other volatiles they contributed. This has been used to infer an origin of life outside of Earth: the panspermia hypothesis.<br />
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类似 Miller-Urey 实验的条件在太阳系的其他区域也存在,常常以紫外线代替闪电作为化学反应的能源。1969年落在默奇森河附近的默奇森陨石被发现含有超过90种不同的氨基酸,其中十九种存在于地球生命中。彗星和其他太阳系外围冰冷的天体被认为含有大量复杂的碳化合物(例如塞林) ,这些碳化合物是由这些天体的暗化表面形成的。早期的地球被彗星大量撞击,可能提供了大量复杂的有机分子以及它们贡献的水和其他挥发物。这被用来推断地球以外生命的起源: 胚种说。<br />
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==Extraterrestrial sources外星源==<br />
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Conditions similar to those of the Miller–Urey experiments are present in other regions of the [[solar system]], often substituting [[ultraviolet]] light for lightning as the energy source for chemical reactions.<ref>{{cite journal|last1=Nunn|first1=JF|title=Evolution of the atmosphere|journal=Proceedings of the Geologists' Association. Geologists' Association|year=1998|volume=109|issue=1|pages=1–13|pmid=11543127|doi=10.1016/s0016-7878(98)80001-1}}</ref><ref>{{cite journal|last1=Raulin|first1=F|last2=Bossard|first2=A|title=Organic syntheses in gas phase and chemical evolution in planetary atmospheres.|journal=Advances in Space Research|year=1984|volume=4|issue=12|pages=75–82|pmid=11537798|doi=10.1016/0273-1177(84)90547-7|bibcode=1984AdSpR...4...75R}}</ref><ref>{{cite journal|last1=Raulin|first1=François|last2=Brassé|first2=Coralie|last3=Poch|first3=Olivier|last4=Coll|first4=Patrice|title=Prebiotic-like chemistry on Titan|journal= Chemical Society Reviews|year=2012|volume=41|issue=16|pages=5380–93|doi=10.1039/c2cs35014a|pmid=22481630}}</ref> The [[Murchison meteorite]] that fell near [[Murchison, Victoria]], Australia in 1969 was found to contain over 90 different amino acids, nineteen of which are found in Earth life. [[Comet]]s and other [[Trans-Neptunian object|icy outer-solar-system bodies]] are thought to contain large amounts of complex carbon compounds (such as [[tholin]]s) formed by these processes, darkening surfaces of these bodies.<ref>{{cite journal |vauthors=Thompson WR, Murray BG, Khare BN, Sagan C |title=Coloration and darkening of methane clathrate and other ices by charged particle irradiation: applications to the outer solar system |journal=Journal of Geophysical Research |volume=92 |issue=A13 |pages=14933–47 |date=December 1987 |pmid=11542127 |doi=10.1029/JA092iA13p14933 |bibcode=1987JGR....9214933T|title-link=methane clathrate }}</ref> The early Earth was bombarded heavily by comets, possibly providing a large supply of complex organic molecules along with the water and other volatiles they contributed.<ref>{{cite journal|last=PIERAZZO|first=E.|author2=CHYBA C.F.|title=Amino acid survival in large cometary impacts|journal=Meteoritics & Planetary Science|year=2010|volume=34|issue=6|pages=909–918|doi=10.1111/j.1945-5100.1999.tb01409.x|bibcode=1999M&PS...34..909P}}</ref> This has been used to infer an origin of life outside of Earth: the [[panspermia]] hypothesis.<br />
与米勒-乌雷实验相似的条件也存在于太阳系的其他区域,通常用紫外线代替闪电作为化学反应的能源。1969年落在澳大利亚维多利亚州默奇森附近的莫奇森陨石被发现含有90多种不同的氨基酸,地球上有19个生命。彗星和其他冰冷的太阳系外天体被认为含有大量由这些过程形成的复杂碳化合物(如索林类化合物),使这些天体的表面变暗。早期地球受到彗星的猛烈轰炸,可能与水和其他挥发物一起提供了大量复杂的有机分子他们对此作出了贡献。这被用来推断地球外生命的起源:胚种假说。<br />
In recent years, studies have been made of the amino acid composition of the products of "old" areas in "old" genes, defined as those that are found to be common to organisms from several widely separated species, assumed to share only the last universal ancestor (LUA) of all extant species. These studies found that the products of these areas are enriched in those amino acids that are also most readily produced in the Miller–Urey experiment. This suggests that the original genetic code was based on a smaller number of amino acids – only those available in prebiotic nature – than the current one.<br />
<br />
近年来,人们对“老”基因中“老”区域的产物的氨基酸组成进行了研究,“老”基因被定义为来自几个相距甚远的物种的生物体所共有的氨基酸组成,这些物种被认为在所有现存物种中只共享最后共同祖先。这些研究发现,这些区域的产物富含那些在 Miller-Urey 实验中也最容易产生的氨基酸。这表明,最初的遗传密码是基于比现在更少的氨基酸-只有那些在益生元性质-比目前的。<br />
<br />
<br />
==Recent related studies近年相关研究==<br />
<br />
Jeffrey Bada, himself Miller's student, inherited the original equipment from the experiment when Miller died in 2007. Based on sealed vials from the original experiment, scientists have been able to show that although successful, Miller was never able to find out, with the equipment available to him, the full extent of the experiment's success. Later researchers have been able to isolate even more different amino acids, 25 altogether. Bada has estimated that more accurate measurements could easily bring out 30 or 40 more amino acids in very low concentrations, but the researchers have since discontinued the testing. Miller's experiment was therefore a remarkable success at synthesizing complex organic molecules from simpler chemicals, considering that all known life uses just 20 different amino acids.<br />
<br />
杰弗里·巴达(Jeffrey Bada)是米勒的学生,他在2007年米勒去世时继承了这项实验的原始设备。根据最初实验中的密封小瓶,科学家们已经能够证明,虽然米勒成功了,但在现有设备的情况下,米勒始终无法发现实验成功的全部程度。后来的研究人员已经能够分离出更多不同的氨基酸,总共25种。Bada估计,更精确的测量可以很容易地在非常低的浓度下提取出30或40种氨基酸,但是研究人员已经停止了这项测试。考虑到所有已知生命只使用20种不同的氨基酸,米勒的实验因此在从较简单的化学物质合成复杂有机分子方面取得了显著成功。<br />
<br />
In recent years, studies have been made of the [[amino acid]] composition of the products of "old" areas in "old" genes, defined as those that are found to be common to organisms from several widely separated [[species]], assumed to share only the [[last universal ancestor]] (LUA) of all extant species. These studies found that the products of these areas are enriched in those amino acids that are also most readily produced in the Miller–Urey experiment. This suggests that the original genetic code was based on a smaller number of amino acids – only those available in prebiotic nature – than the current one.<ref>{{cite journal |author1=Brooks D.J. |author2=Fresco J.R. |author3=Lesk A.M. |author4=Singh M. |url=http://mbe.oupjournals.org/cgi/content/full/19/10/1645 |title=Evolution of amino acid frequencies in proteins over deep time: inferred order of introduction of amino acids into the genetic code |journal=Molecular Biology and Evolution |date=October 1, 2002 |volume=19 |pages=1645–55 |pmid=12270892 |issue=10 |doi=10.1093/oxfordjournals.molbev.a003988 |url-status=dead |archiveurl=https://web.archive.org/web/20041213094516/http://mbe.oupjournals.org/cgi/content/full/19/10/1645 |archivedate=December 13, 2004 |doi-access=free }}</ref><br />
近年来,人们对“老”基因中“老”区域产物的氨基酸组成进行了研究,这些“老”基因被定义为是几种广泛分离的物种的有机体所共有的氨基酸成分,假设它们只共享所有现存物种的最后一个宇宙祖先(LUA)。这些研究发现,这些地区的产品富含在米勒-尤里实验中最容易产生的氨基酸。这表明,最初的遗传密码是基于比现在更少的氨基酸-只有那些在益生元性质-比目前的<br />
<br />
<br />
In 2008, a group of scientists examined 11 vials left over from Miller's experiments of the early 1950s. In addition to the classic experiment, reminiscent of Charles Darwin's envisioned "warm little pond", Miller had also performed more experiments, including one with conditions similar to those of volcanic eruptions. This experiment had a nozzle spraying a jet of steam at the spark discharge. By using high-performance liquid chromatography and mass spectrometry, the group found more organic molecules than Miller had. They found that the volcano-like experiment had produced the most organic molecules, 22 amino acids, 5 amines and many hydroxylated molecules, which could have been formed by hydroxyl radicals produced by the electrified steam. The group suggested that volcanic island systems became rich in organic molecules in this way, and that the presence of carbonyl sulfide there could have helped these molecules form peptides.<br />
<br />
2008年,一组科学家检查了米勒20世纪50年代早期实验遗留下来的11个小瓶。除了经典的实验(让人想起查尔斯·达尔文设想的“温暖的小池塘”)外,米勒还进行了更多的实验,其中一个实验的条件与火山爆发时相似。这个实验有一个喷嘴在火花放电处喷射蒸汽。通过使用高效液相色谱和质谱,研究小组发现了比米勒更多的有机分子。他们发现,类似火山的实验产生了最多的有机分子,22个氨基酸,5个胺和许多羟基化分子,这些分子可能是由通电蒸汽产生的羟基自由基形成的。研究小组认为,火山岛系统以这种方式富含有机分子,而羰基硫化物的存在可能有助于这些分子形成肽。 <br />
[[Jeffrey Bada]], himself Miller's student, inherited the original equipment from the experiment when Miller died in 2007. Based on sealed vials from the original experiment, scientists have been able to show that although successful, Miller was never able to find out, with the equipment available to him, the full extent of the experiment's success. Later researchers have been able to isolate even more different amino acids, 25 altogether. Bada has estimated that more accurate measurements could easily bring out 30 or 40 more amino acids in very low concentrations, but the researchers have since discontinued the testing. Miller's experiment was therefore a remarkable success at synthesizing complex organic molecules from simpler chemicals, considering that all known life uses just 20 different amino acids.<ref name="BBC">{{cite web |website=BBC Four |url=http://www.bbc.co.uk/programmes/b00mbvfh |title=The Spark of Life |url-status=live |archive-url=https://web.archive.org/web/20101113011054/http://www.bbc.co.uk/programmes/b00mbvfh |archive-date=2010-11-13 |postscript=. TV Documentary. |date=26 August 2009}}</ref><br />
杰弗里·巴达(Jeffrey Bada)是米勒的学生,他在2007年米勒去世时继承了这项实验的原始设备。根据最初实验中的密封小瓶,科学家们已经能够证明,虽然米勒成功了,但在现有设备的情况下,米勒始终无法发现实验成功的全部程度。后来的研究人员已经能够分离出更多不同的氨基酸,总共25种。Bada估计,更精确的测量可以很容易地在非常低的浓度下提取出30或40种氨基酸,但是研究人员已经停止了这项测试。考虑到所有已知生命只使用20种不同的氨基酸,米勒的实验因此在从较简单的化学物质合成复杂有机分子方面取得了显著成功。<br />
<br />
<br />
The main problem of theories based around amino acids is the difficulty in obtaining spontaneous formation of peptides. Since John Desmond Bernal's suggestion that clay surfaces could have played a role in abiogenesis, scientific efforts have been dedicated to investigating clay-mediated peptide bond formation, with limited success. Peptides formed remained over-protected and shown no evidence of inheritance or metabolism. In December 2017 a theoretical model developed by Erastova and collaborators suggested that peptides could form at the interlayers of layered double hydroxides such as green rust in early earth conditions. According to the model, drying of the intercalated layered material should provide energy and co-alignment required for peptide bond formation in a ribosome-like fashion, while re-wetting should allow mobilising the newly formed peptides and repopulate the interlayer with new amino acids. This mechanism is expected to lead to the formation of 12+ amino acid-long peptides within 15-20 washes. Researches also observed slightly different adsorption preferences for different amino acids, and postulated that, if coupled to a diluted solution of mixed amino acids, such preferences could lead to sequencing.<br />
<br />
以氨基酸为基础的理论的主要问题是很难获得肽的自发形成。自从约翰·德斯蒙德·伯纳尔提出粘土表面可能在自然发生中起作用以来,科学家致力于研究粘土介导的肽键的形成,但成效有限。形成的肽保护过度,没有遗传或新陈代谢的证据。2017年12月,Erastova和他的合作者开发的一个理论模型表明,在早期的地球条件下,多肽可以在层状双氢氧化物的中间层形成,例如绿锈。根据该模型,插层材料的干燥应提供能量和以核糖体样的方式形成肽键所需的共排列,而再湿润应允许活化新形成的肽和重新填充层与新的氨基酸。这一机制有望在15-20次洗涤过程中形成12 + 氨基酸长肽。研究人员还观察到对不同氨基酸的吸附偏好略有不同,并假定,如果与混合氨基酸的稀释溶液相结合,这种偏好可能导致排序。<br />
<br />
In 2008, a group of scientists examined 11 vials left over from Miller's experiments of the early 1950s. In addition to the classic experiment, reminiscent of [[Charles Darwin]]'s envisioned "warm little pond", Miller had also performed more experiments, including one with conditions similar to those of [[volcano|volcanic]] eruptions. This experiment had a nozzle spraying a jet of steam at the spark discharge. By using [[high-performance liquid chromatography]] and [[mass spectrometry]], the group found more organic molecules than Miller had. They found that the volcano-like experiment had produced the most organic molecules, 22 amino acids, 5 [[amine]]s and many [[hydroxylate]]d molecules, which could have been formed by [[hydroxyl radical]]s produced by the electrified steam. The group suggested that volcanic island systems became rich in organic molecules in this way, and that the presence of [[carbonyl sulfide]] there could have helped these molecules form [[peptide]]s.<ref name=Johnson2008>{{cite journal |vauthors=Johnson AP, Cleaves HJ, Dworkin JP, Glavin DP, Lazcano A, Bada JL |title=The Miller volcanic spark discharge experiment |journal=Science |volume=322 |issue=5900 |pages=404 |date=October 2008 |pmid=18927386 |doi=10.1126/science.1161527|bibcode = 2008Sci...322..404J }}</ref><ref>{{cite web | title='Lost' Miller–Urey Experiment Created More Of Life's Building Blocks | date=October 17, 2008 | website=Science Daily | url=https://www.sciencedaily.com/releases/2008/10/081016141411.htm | accessdate=2008-10-18 | url-status=live | archiveurl=https://web.archive.org/web/20081019111114/http://www.sciencedaily.com/releases/2008/10/081016141411.htm | archivedate=October 19, 2008 }}</ref><br />
20世纪50年代,除了经典的实验,让人想起查尔斯达尔文设想的“温暖的小池塘”,米勒还进行了更多的实验,包括一个条件类似于火山喷发的实验。这个实验有一个喷嘴在火花放电处喷射蒸汽。通过液相色谱法和质谱法发现了比米勒组更多的有机分子。他们发现,类似火山的实验产生了最多的有机分子,22个氨基酸,5个胺和许多羟基化分子,这些分子可能是由通电蒸汽产生的羟基自由基形成的。该小组认为,火山岛系统通过这种方式变得富含有机分子,而那里的羰基硫化物可能有助于这些分子形成肽。<br />
<br />
<br />
In October 2018, researchers at McMaster University on behalf of the Origins Institute announced the development of a new technology, called a Planet Simulator, to help study the origin of life on planet Earth and beyond.<br />
<br />
2018年10月,麦马士达大学的研究人员代表起源研究所宣布了一项名为行星模拟器的新技术的发展,以帮助研究行星地球及其他地方的生命起源。<br />
<br />
The main problem of theories based around [[amino acids]] is the difficulty in obtaining spontaneous formation of peptides. Since [[John Desmond Bernal]]'s suggestion that clay surfaces could have played a role in [[abiogenesis]]<ref name=Bernal1949>{{cite journal |vauthors=Bernal JD |title=The physical basis of life |journal=Proc. Phys. Soc. A | issue=9 |volume=62 |pages=537–558 |date=1949|doi=10.1088/0370-1298/62/9/301 |bibcode=1949PPSA...62..537B }}</ref>, scientific efforts have been dedicated to investigating clay-mediated [[peptide bond]] formation, with limited success. Peptides formed remained over-protected and shown no evidence of inheritance or metabolism. In December 2017 a theoretical model developed by Erastova and collaborators <ref name="RT-2018">{{cite news | publisher=RT | url=https://www.rt.com/news/416581-scientists-unlock-life-puzzle-protein/ | title='How did life form from rocks?' Protein puzzle reveals secrets of Earth's evolution | date=January 2017}}</ref><ref name="Erastova2017">{{cite journal |vauthors=Erastova V, Degiacomi MT, Fraser D, Greenwell HC |title=Mineral surface chemistry control for origin of prebiotic peptides |journal=Nature Communications |volume=8 |issue=1 |pages=2033 |date=December 2017|pmid=29229963 |pmc=5725419 |doi=10.1038/s41467-017-02248-y |bibcode=2017NatCo...8.2033E }}</ref> suggested that peptides could form at the interlayers of [[layered double hydroxides]] such as [[green rust]] in early earth conditions. According to the model, drying of the intercalated layered material should provide energy and co-alignment required for peptide bond formation in a [[ribosome]]-like fashion, while re-wetting should allow mobilising the newly formed peptides and repopulate the interlayer with new amino acids. This mechanism is expected to lead to the formation of 12+ amino acid-long peptides within 15-20 washes. Researches also observed slightly different adsorption preferences for different amino acids, and postulated that, if coupled to a diluted solution of mixed amino acids, such preferences could lead to sequencing.<br />
以氨基酸为基础的理论的主要问题是难以获得肽的自发形成。自从John Desmond Bernal提出粘土表面可能在非生物发生中起作用[36]以来,科学界一直致力于研究粘土介导的肽键形成,但收效甚微。形成的肽仍然受到过度保护,没有遗传或代谢的证据。2017年12月,Erastova及其合作者开发的一个理论模型表明,在早期地球条件下,肽可以在层状双氢氧化物(如绿锈)的层间形成。根据该模型,夹层材料的干燥应能以类似假种体的方式提供肽键形成所需的能量和协同排列,而再润湿应能使新形成的肽活化,并在夹层中重新填充新的氨基酸。这一机制有望在15-20次洗涤过程中形成12+氨基酸长肽。研究还观察到不同氨基酸的吸附偏好稍有不同,并假设,如果与混合氨基酸的稀释溶液相结合,这种偏好可能导致测序。<br />
<br />
<br />
In October 2018, researchers at [[McMaster University]] on behalf of the [[Origins Institute]] announced the development of a new technology, called a ''[[Planet Simulator]]'', to help study the [[origin of life]] on planet [[Earth]] and beyond.<ref name="BW-20181004">{{cite news |last=Balch |first=Erica |title=Ground-breaking lab poised to unlock the mystery of the origins of life on Earth and beyond |url=https://brighterworld.mcmaster.ca/articles/ground-breaking-lab-poised-to-unlock-the-mystery-of-the-origins-of-life-on-earth-and-beyond/ |date=4 October 2018 |work=[[McMaster University]] |accessdate=4 October 2018 }}</ref><ref name="EA-20181004">{{cite news |author=Staff |title=Ground-breaking lab poised to unlock the mystery of the origins of life |url=https://www.eurekalert.org/pub_releases/2018-10/mu-glp100418.php |date=4 October 2018 |work=[[EurekAlert!]] |accessdate=14 October 2018 }}</ref><ref name="IVG-2018">{{cite web |author=Staff |title=Planet Simulator |url=https://www.intravisiongroup.com/planet-simulator |date=2018 |work=IntraVisionGroup.com |accessdate=14 October 2018 }}</ref><ref name="ES-209181014">{{cite web |last=Anderson |first=Paul Scott |title=New technology may help solve mystery of life's origins - How did life on Earth begin? A new technology, called Planet Simulator, might finally help solve the mystery. |url=http://earthsky.org/space/new-technology-solve-mystery-of-lifes-origins |date=14 October 2018 |work=[[EarthSky]] |accessdate=14 October 2018 }}</ref><br />
<br />
2018年10月,麦克马斯特大学(McMaster University)的研究人员代表起源研究所(Origins Institute)宣布开发一种新技术,名为“行星模拟器”(Planet Simulator),以帮助研究行星地球及其他星球上生命的起源。<br />
<br />
==Amino acids identified氨基酸鉴定 ==<br />
<br />
Below is a table of amino acids produced and identified in the "classic" 1952 experiment, as published by Miller in 1953, and the 2010 re-analysis of vials from the H<sub>2</sub>S-rich spark discharge experiment.<br />
<br />
下面是由 Miller 在1953年发表的1952年“经典”实验中产生和鉴定的氨基酸表,以及2010年对H2S高密度火花放电实验中小瓶的重新分析。<br />
<br />
{{Category see also|Chemical synthesis of amino acids}}<br />
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<br />
{|class="wikitable sortable" style="text-align:right"<br />
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{ | class = “ wikitable sortable” style = “ text-align: right”<br />
<br />
Below is a table of amino acids produced and identified in the "classic" 1952 experiment, as published by Miller in 1953,<ref name=miller1953/> the 2008 re-analysis of vials from the volcanic spark discharge experiment,<ref>{{cite web|last1=Myers|first1=P. Z.|title=Old scientists never clean out their refrigerators|url=http://scienceblogs.com/pharyngula/2008/10/old_scientists_never_clean_out.php|website=Pharyngula|accessdate=7 April 2016|archiveurl=https://web.archive.org/web/20081017231050/http://scienceblogs.com/pharyngula/2008/10/old_scientists_never_clean_out.php|archivedate=October 17, 2008|date=October 16, 2008}}</ref> and the 2010 re-analysis of vials from the H<sub>2</sub>S-rich spark discharge experiment.<ref>{{cite journal|title=Primordial synthesis of amines and amino acids in a 1958 Miller H2S-rich spark discharge experiment|journal=Proceedings of the National Academy of Sciences|date=February 14, 2011|volume=108|issue=14|doi=10.1073/pnas.1019191108|pmid=21422282|pmc=3078417|pages=5526–31|last1=Parker|first1=ET|last2=Cleaves|first2=HJ|last3=Dworkin|first3=JP|display-authors=etal |bibcode=2011PNAS..108.5526P|df=}}</ref><br />
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! scope="col" rowspan="2" | Amino acid<br />
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!范围 = “ col” rowspan = “2” | 氨基酸<br />
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{|class="wikitable sortable" style="text-align:right"<br />
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! scope="col" colspan="3" | Produced in experiment<br />
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! scope="col" rowspan="2" | Proteinogenic<br />
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!Scope = “ col” rowspan = “2” | Proteinogenic<br />
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! scope="col" rowspan="2" | Amino acid<br />
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! scope="col" colspan="3" | Produced in experiment<br />
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! scope="col" | Miller–Urey<br/><br />
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!“ col” | Miller-Urey < br/> <br />
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! scope="col" rowspan="2" | [[Proteinogenic]]<br />
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! scope="col" | Volcanic spark discharge<br/><br />
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!火山火花放电 < br/> <br />
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! scope="col" | H<sub>2</sub>S-rich spark discharge<br/><br />
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!范围 = “ col” | h < sub > 2 </sub > 富 s 火花放电 < br/> <br />
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! scope="col" | Miller–Urey<br/>{{small|(1952)}}<br />
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! scope="col" | Volcanic spark discharge<br/>{{small|(2008)}}<br />
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|Glycine<br />
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| 甘氨酸<br />
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! scope="col" | H<sub>2</sub>S-rich spark discharge<br/>{{small|(2010)}}<br />
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| {{ya}}<br />
<br />
|α-Alanine<br />
<br />
|α-Alanine<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[alanine|α-Alanine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|β-Alanine<br />
<br />
|β-Alanine<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[beta-Alanine|β-Alanine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Aspartic acid<br />
<br />
天冬氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Aspartic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|α-Aminobutyric acid<br />
<br />
|α-Aminobutyric acid<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[alpha-Aminobutyric acid|α-Aminobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Serine<br />
<br />
| Serine<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Serine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Isoserine<br />
<br />
| 异丝氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Isoserine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|α-Aminoisobutyric acid<br />
<br />
|α-Aminoisobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[2-Aminoisobutyric acid|α-Aminoisobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|β-Aminoisobutyric acid<br />
<br />
|β-Aminoisobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[3-Aminoisobutyric acid|β-Aminoisobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|β-Aminobutyric acid<br />
<br />
|β-Aminobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[beta-Aminobutyric acid|β-Aminobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|γ-Aminobutyric acid<br />
<br />
|γ-Aminobutyric acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[gamma-Aminobutyric acid|γ-Aminobutyric acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Valine<br />
<br />
瓦林<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Valine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Isovaline<br />
<br />
异缬氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Isovaline]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Glutamic acid<br />
<br />
谷氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Glutamic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Norvaline<br />
<br />
诺瓦林<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Norvaline]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|α-Aminoadipic acid<br />
<br />
Α-氨基己二酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[alpha-Aminoadipic acid|α-Aminoadipic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Homoserine<br />
<br />
高丝氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Homoserine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|2-Methylserine<br />
<br />
| 2- 甲基丝氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[2-Methylserine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|β-Hydroxyaspartic acid<br />
<br />
|β-Hydroxyaspartic acid<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[3-Hydroxyaspartic acid|β-Hydroxyaspartic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Ornithine<br />
<br />
鸟氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Ornithine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|2-Methylglutamic acid<br />
<br />
| 2- 甲基谷氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[2-Methylglutamic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Phenylalanine<br />
<br />
| 苯丙氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Phenylalanine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{ya}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Homocysteic acid<br />
<br />
高同型半胱氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Homocysteic acid]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|S-Methylcysteine<br />
<br />
S- 甲基半胱氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[S-methylcysteine|''S''-Methylcysteine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Methionine<br />
<br />
| 蛋氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Methionine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Methionine sulfoxide<br />
<br />
蛋氨酸亚砜<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Methionine sulfoxide]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Methionine sulfone<br />
<br />
蛋氨酸砜<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Methionine sulfone]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Isoleucine<br />
<br />
异亮氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Isoleucine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Leucine<br />
<br />
亮氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Leucine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Ethionine<br />
<br />
|Ethionine<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Ethionine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Cysteine<br />
<br />
半胱氨酸<br />
<br />
| {{no}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Cysteine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Histidine<br />
<br />
| 组氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Histidine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Lysine<br />
<br />
赖氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Lysine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Asparagine<br />
<br />
天冬酰胺<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Asparagine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Pyrrolysine<br />
<br />
| 吡咯赖氨酸<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Pyrrolysine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Proline<br />
<br />
| Proline<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Proline]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{ya}}<br />
<br />
|Glutamine<br />
<br />
谷氨酰胺<br />
<br />
| {{yes}}<br />
<br />
| <br />
<br />
|<br />
<br />
|-<br />
<br />
| <br />
<br />
|<br />
<br />
|[[Glutamine]]<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
| <br />
<br />
|<br />
<br />
| {{na}}<br />
<br />
|-<br />
<br />
|-<br />
<br />
| {{na}}<br />
<br />
|Arginine<br />
<br />
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==References参考==<br />
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{{Reflist|30em}}<br />
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==External links外部链接==<br />
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*[http://millerureyexperiment.com A simulation of the Miller–Urey Experiment along with a video Interview with Stanley Miller] by Scott Ellis from CalSpace (UCSD)<br />
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* [https://web.archive.org/web/20081019122408/http://www.pubs.acs.org/cen/news/86/i42/8642notw4.html Origin-Of-Life Chemistry Revisited: Reanalysis of famous spark-discharge experiments reveals a richer collection of amino acids were formed.] <br />
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* [https://web.archive.org/web/20090821213017/http://www.chem.duke.edu/~jds/cruise_chem/Exobiology/miller.html Miller–Urey experiment explained]<br />
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* [http://www.althofer.de/miller-experiment-with-lego.html Miller experiment with Lego bricks]<br />
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*[https://www.pbs.org/exploringspace/meteorites/murchison/page5.html "Stanley Miller's Experiment: Sparking the Building Blocks of Life" on PBS]<br />
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*[http://www.millerureyexperiment.com/ The Miller-Urey experiment website]<br />
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*{{cite journal|doi=10.1016/0022-5193(66)90178-0|pmid=5964688|title=The origin of life and the nature of the primitive gene|journal=Journal of Theoretical Biology|volume=10|issue=1|pages=53–88|year=1966|last1=Cairns-Smith|first1=A.G.}}<br />
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*[http://astrobiology.gsfc.nasa.gov/analytical/PDF/Johnsonetal2008.pdf Details of 2008 re-analysis]<br />
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<small>This page was moved from [[wikipedia:en:Miller–Urey experiment]]. Its edit history can be viewed at [[米勒-尤里实验/edithistory]]</small></noinclude><br />
<br />
[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E6%9C%89%E6%95%88%E5%9C%BA%E8%AE%BA&diff=18465有效场论2020-11-16T09:25:58Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{More footnotes|date=May 2013}}<br />
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{{Quantum field theory|cTopic=Some models}}<br />
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In [[physics]], an '''effective field theory''' is a type of approximation, or [[effective theory]], for an underlying physical theory, such as a [[quantum field theory]] or a [[statistical mechanics]] model. An effective field theory includes the appropriate [[degrees of freedom (physics and chemistry)|degrees of freedom]] to describe physical phenomena occurring at a chosen [[length scale]] or energy scale, while ignoring substructure and degrees of freedom at shorter distances (or, equivalently, at higher energies). Intuitively, one averages over the behavior of the underlying theory at shorter length scales to derive what is hoped to be a simplified model at longer length scales. Effective field theories typically work best when there is a large separation between length scale of interest and the length scale of the underlying dynamics. Effective field theories have found use in [[particle physics]], [[statistical mechanics]], [[condensed matter physics]], [[general relativity]], and [[hydrodynamics]]. They simplify calculations, and allow treatment of [[Dissipative system|dissipation]] and [[radiation]] effects.<ref>{{Cite journal|doi=10.1103/PhysRevLett.110.174301|pmid=23679733|url=http://authors.library.caltech.edu/38643/1/PhysRevLett.110.174301.pdf|title=Classical Mechanics of Nonconservative Systems|journal=Physical Review Letters|volume=110|issue=17|pages=174301|year=2013|last1=Galley|first1=Chad R.|s2cid=14591873|access-date=2014-03-03|archive-url=https://web.archive.org/web/20140303174914/http://authors.library.caltech.edu/38643/1/PhysRevLett.110.174301.pdf|archive-date=2014-03-03|url-status=dead}}</ref><ref>{{Cite journal |arxiv = 1402.2610|last1 = Birnholtz|first1 = Ofek|title = Radiation reaction at the level of the action|journal = International Journal of Modern Physics A|volume = 29|issue = 24|pages = 1450132|last2 = Hadar|first2 = Shahar|last3 = Kol|first3 = Barak|year = 2014|doi = 10.1142/S0217751X14501322|s2cid = 118541484}}</ref><br />
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In physics, an effective field theory is a type of approximation, or effective theory, for an underlying physical theory, such as a quantum field theory or a statistical mechanics model. An effective field theory includes the appropriate degrees of freedom to describe physical phenomena occurring at a chosen length scale or energy scale, while ignoring substructure and degrees of freedom at shorter distances (or, equivalently, at higher energies). Intuitively, one averages over the behavior of the underlying theory at shorter length scales to derive what is hoped to be a simplified model at longer length scales. Effective field theories typically work best when there is a large separation between length scale of interest and the length scale of the underlying dynamics. Effective field theories have found use in particle physics, statistical mechanics, condensed matter physics, general relativity, and hydrodynamics. They simplify calculations, and allow treatment of dissipation and radiation effects.<br />
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在物理学中,<font color="#ff8000"> 有效场论Effective field theory</font>是一种近似的理论,或者说是一种有效的理论,用于基础的物理理论,比如量子场论或者统计力学模型理论。一个有效的场论包括用适当的自由度来描述在选定的长度尺度或能量尺度下发生的物理现象,而忽略在较短距离上的子结构和自由度(或者等效地,在较高的能量上)。直观上,一个人可以用较短的长度尺度对潜在理论的行为进行平均,从而希望得出一个在较长长度尺度下的简化模型。有效的领域理论通常最好的时候有一个大分离的我们感兴趣的长度尺度和长度尺度的基本动态。有效的场理论已经在粒子物理学、统计力学、凝聚态物理学、广义相对论和流体力学中得到了应用。它们简化了计算,并可以处理耗散和辐射效应。<br />
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==The renormalization group重整化群 ==<br />
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Presently, effective field theories are discussed in the context of the [[renormalization group]] (RG) where the process of ''integrating out'' short distance degrees of freedom is made systematic. Although this method is not sufficiently concrete to allow the actual construction of effective field theories, the gross understanding of their usefulness becomes clear through an RG analysis. This method also lends credence to the main technique of constructing effective field theories, through the analysis of [[symmetry|symmetries]]. If there is a single mass scale '''M''' in the ''microscopic'' theory, then the effective field theory can be seen as an expansion in '''1/M'''. The construction of an effective field theory accurate to some power of '''1/M''' requires a new set of free parameters at each order of the expansion in '''1/M'''. This technique is useful for [[scattering]] or other processes where the maximum momentum scale '''k''' satisfies the condition '''k/M≪1'''. Since effective field theories are not valid at small length scales, they need not be [[Renormalization#Renormalizability|renormalizable]]. Indeed, the ever expanding number of parameters at each order in '''1/M''' required for an effective field theory means that they are generally not renormalizable in the same sense as [[quantum electrodynamics]] which requires only the renormalization of two parameters.<br />
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Presently, effective field theories are discussed in the context of the renormalization group (RG) where the process of integrating out short distance degrees of freedom is made systematic. Although this method is not sufficiently concrete to allow the actual construction of effective field theories, the gross understanding of their usefulness becomes clear through an RG analysis. This method also lends credence to the main technique of constructing effective field theories, through the analysis of symmetries. If there is a single mass scale M in the microscopic theory, then the effective field theory can be seen as an expansion in 1/M. The construction of an effective field theory accurate to some power of 1/M requires a new set of free parameters at each order of the expansion in 1/M. This technique is useful for scattering or other processes where the maximum momentum scale k satisfies the condition k/M≪1. Since effective field theories are not valid at small length scales, they need not be renormalizable. Indeed, the ever expanding number of parameters at each order in 1/M required for an effective field theory means that they are generally not renormalizable in the same sense as quantum electrodynamics which requires only the renormalization of two parameters.<br />
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目前,有效场理论是在<font color="#ff8000"> 重整化群Renormalization group</font>(RG)的背景下讨论的,重整化群使短距离自由度的积分过程变得系统化。尽管这种方法不够具体,无法实际构建有效场理论,但通过RG分析,对其有用性的总体理解变得清晰。通过对对称性的分析,该方法也为构造有效场理论的主要技术提供了依据。如果微观理论中只有一个质量尺度M,因此,有效场理论可以看作是1/M的展开式。建立精确到1/M幂次的有效场理论需要在1/M展开的每一阶上都有一组新的自由参数。这种方法对于散射或其他最大动量标度k满足条件k/M≪1的过程是有用的。由于有效场理论在小尺度下是无效的,所以它们不必是可重正化的。事实上,有效场理论所要求的每阶1/M的参数数目不断增加,这意味着它们通常不能像只需要两个参数重正化的量子电动力学那样可重整化。<br />
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==Examples of effective field theories有效场理论实例==<br />
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===Fermi theory of beta decay贝塔衰变的费米理论 ===<br />
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The best-known example of an effective field theory is the [[Fermi's interaction|Fermi theory of beta decay]]. This theory was developed during the early study of weak decays of [[Atomic nucleus|nuclei]] when only the [[hadron]]s and [[lepton]]s undergoing weak decay were known. The typical [[elementary particle reaction|reactions]] studied were:<br />
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The best-known example of an effective field theory is the Fermi theory of beta decay. This theory was developed during the early study of weak decays of nuclei when only the hadrons and leptons undergoing weak decay were known. The typical reactions studied were:<br />
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有效场理论最著名的例子是贝塔衰变费米理论。这个理论是在早期研究弱衰变核时发展起来的,当时物理学家只知道经历弱衰变的强子和轻子。研究的典型反应有:<br />
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《数学》<br />
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N & to p + e ^-+ overline nu _ e<br />
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\mu^- & \to e^-+\overline\nu_e+\nu_\mu.<br />
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\mu^- & \to e^-+\overline\nu_e+\nu_\mu.<br />
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Mu ^-& to e ^-+ overline nu _ e + nu _ mu.<br />
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数学<br />
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This theory posited a pointlike interaction between the four [[fermion]]s involved in these reactions. The theory had great [[phenomenology (particle physics)|phenomenological]] success and was eventually understood to arise from the [[gauge theory]] of [[electroweak interaction]]s, which forms a part of the [[standard model]] of particle physics. In this more fundamental theory, the interactions are mediated by a [[flavour (particle physics)|flavour]]-changing [[gauge boson]], the W<sup>±</sup>. The immense success of the Fermi theory was because the W particle has mass of about 80 [[GeV]], whereas the early experiments were all done at an energy scale of less than 10 [[MeV]]. Such a separation of scales, by over 3 orders of magnitude, has not been met in any other situation as yet.<br />
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This theory posited a pointlike interaction between the four fermions involved in these reactions. The theory had great phenomenological success and was eventually understood to arise from the gauge theory of electroweak interactions, which forms a part of the standard model of particle physics. In this more fundamental theory, the interactions are mediated by a flavour-changing gauge boson, the W<sup>±</sup>. The immense success of the Fermi theory was because the W particle has mass of about 80 GeV, whereas the early experiments were all done at an energy scale of less than 10 MeV. Such a separation of scales, by over 3 orders of magnitude, has not been met in any other situation as yet.<br />
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这个理论假定了参与这些反应的四个费米子之间的点状相互作用。这个理论在现象学上取得了巨大的成功,并最终被理解为产生于弱电相互作用的规范理论,它构成了粒子物理学标准模型的一部分。在这个更基本的理论中,相互作用是由一个可以改变味的规范玻色子w±介导的。费米理论的巨大成功是因为 w 粒子的质量约为80gev,而早期的实验都是在能量小于10mev 的情况下进行的。这样的分离在超过3个数量级时,还没有在任何其他情况下达到。<br />
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===BCS theory of superconductivityBCS超导理论 ===<br />
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Another famous example is the [[BCS theory]] of [[superconductivity]]. Here the underlying theory is of [[electron]]s in a [[metal]] interacting with lattice vibrations called [[phonon]]s. The phonons cause attractive interactions between some electrons, causing them to form [[Cooper pair]]s. The length scale of these pairs is much larger than the wavelength of phonons, making it possible to neglect the dynamics of phonons and construct a theory in which two electrons effectively interact at a point. This theory has had remarkable success in describing and predicting the results of experiments on superconductivity.<br />
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Another famous example is the BCS theory of superconductivity. Here the underlying theory is of electrons in a metal interacting with lattice vibrations called phonons. The phonons cause attractive interactions between some electrons, causing them to form Cooper pairs. The length scale of these pairs is much larger than the wavelength of phonons, making it possible to neglect the dynamics of phonons and construct a theory in which two electrons effectively interact at a point. This theory has had remarkable success in describing and predicting the results of experiments on superconductivity.<br />
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另一个著名的例子是超导现象的 BCS 理论。这里的基本理论是金属中的电子与称为声子的晶格振动相互作用。声子在一些电子之间引起吸引力的相互作用,导致它们形成库珀对。这些对的长度比声子的波长大得多,因此可以忽略声子的动力学,并建立一个两个电子在一个点上有效相互作用的理论。这个理论在描述和预测超导现象的实验结果方面取得了显著的成功。<br />
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===Effective Field Theories in Gravity重力中的有效场理论 ===<br />
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[[General relativity]] itself is expected to be the low energy effective field theory of a full theory of [[quantum gravity]], such as [[string theory]] or [[Loop Quantum Gravity]]. The expansion scale is the [[Planck mass]].<br />
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General relativity itself is expected to be the low energy effective field theory of a full theory of quantum gravity, such as string theory or Loop Quantum Gravity. The expansion scale is the Planck mass.<br />
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<font color="#ff8000"> 广义相对论General relativity</font>本身有望成为完整的量子引力理论的低能有效场论,如弦论或回圈量子重力理论。膨胀尺度是普朗克质量。<br />
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Effective field theories have also been used to simplify problems in General Relativity, in particular in calculating the [[gravitational wave]] signature of inspiralling finite-sized objects.<ref>{{Cite journal |arxiv = hep-th/0409156|last1 = Goldberger|first1 = Walter|title = An Effective Field Theory of Gravity for Extended Objects|journal = Physical Review D|volume = 73|issue = 10|last2 = Rothstein|first2 = Ira|year = 2004|doi = 10.1103/PhysRevD.73.104029|s2cid = 54188791}}</ref> The most common EFT in GR is "[[Non-Relativistic General Relativity]]" (NRGR),<ref>[http://online.kitp.ucsb.edu/online/numrel-m08/buonanno/pdf1/Porto_NumRelData_KITP.pdf]</ref><ref>{{Cite journal |arxiv = 0712.4116|last1 = Kol|first1 = Barak|title = Non-Relativistic Gravitation: From Newton to Einstein and Back|journal = Classical and Quantum Gravity|volume = 25|issue = 14|pages = 145011|last2 = Smolkin|first2 = Lee|year = 2008|doi = 10.1088/0264-9381/25/14/145011|s2cid = 119216835}}</ref><ref>{{Cite journal |arxiv = gr-qc/0511061|last1 = Porto|first1 = Rafael A|title = Post-Newtonian corrections to the motion of spinning bodies in NRGR|journal = Physical Review D|volume = 73|issue = 104031|pages = 104031|year = 2006|doi = 10.1103/PhysRevD.73.104031|s2cid = 119377563}}</ref> which is similar to the [[post-Newtonian expansion]].<ref>{{Cite journal |doi = 10.1103/PhysRevD.88.104037|title = Theory of post-Newtonian radiation and reaction|journal = Physical Review D|volume = 88|issue = 10|pages = 104037|year = 2013|last1 = Birnholtz|first1 = Ofek|last2 = Hadar|first2 = Shahar|last3 = Kol|first3 = Barak|arxiv = 1305.6930|s2cid = 119170985}}</ref> Another common GR EFT is the Extreme Mass Ratio (EMR), which in the context of the inspiralling problem is called [[Extreme mass ratio inspiral|EMRI]].<br />
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Effective field theories have also been used to simplify problems in General Relativity, in particular in calculating the gravitational wave signature of inspiralling finite-sized objects. The most common EFT in GR is "Non-Relativistic General Relativity" (NRGR), which is similar to the post-Newtonian expansion. Another common GR EFT is the Extreme Mass Ratio (EMR), which in the context of the inspiralling problem is called EMRI.<br />
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有效的场理论也被用来简化广义相对论中的问题,特别是在计算有限大小的物体的引力波特征时。GR 中最常见的 EFT 是“非相对论广义相对论”(NRGR) ,它类似于后牛顿力学近似方法。另一个常见的 GR EFT 是极端质量比(EMR) ,在激励问题的背景下被称为 EMRI。<br />
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===Other examples其他例子===<br />
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Presently, effective field theories are written for many situations.<br />
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Presently, effective field theories are written for many situations.<br />
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目前,有效场理论是针对多种情况而编写的。<br />
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*One major branch of [[nuclear physics]] is [[quantum hadrodynamics]], where the interactions of [[hadron]]s are treated as a field theory, which should be derivable from the underlying theory of [[quantum chromodynamics]]. Quantum hadrodynamics is the theory of the [[nuclear force]], similarly to quantum chromodynamics being the theory of the [[strong interaction]] and quantum electrodynamics being the theory of the [[electromagnetic force]]. Due to the smaller separation of length scales here, this effective theory has some classificatory power, but not the spectacular success of the Fermi theory.<br />
*[[量子物理]]的一个主要分支是[[量子强子动力学]],其中[[强子]]的相互作用被视为场理论,它应该从[[量子色动力学]]的基础理论中衍生出来。量子强子动力学是[[核力]]的理论,类似于量子色动力学是[[强相互作用]的理论,量子电动力学是[[电磁力]的理论。由于长度尺度的分离较小,这一有效理论具有一定的分类能力,但没有费米理论的惊人成功。<br />
*In [[particle physics]] the effective field theory of [[Quantum chromodynamics|QCD]] called [[chiral perturbation theory]] has had better success.<ref>{{Cite journal |arxiv = hep-ph/9311274|last1 = Leutwyler|first1 = H|title = On the Foundations of Chiral Perturbation Theory|journal = Annals of Physics|volume = 235|pages = 165–203|year = 1994|doi = 10.1006/aphy.1994.1094|s2cid = 16739698}}</ref> This theory deals with the interactions of [[hadron]]s with [[pion]]s or [[kaon]]s, which are the [[Goldstone boson]]s of [[spontaneous chiral symmetry breaking]]. The expansion parameter is the [[pion]] energy/momentum.<br />
在[[粒子物理]]中,[[量子色动力学| QCD]]中称为[[手征微扰理论]的有效场理论有更好的表现成功。他的理论研究[[强子]]s与[[π]]s或[[kaon]]s的相互作用,它们是[[自发手征对称性破坏]]的[[金石玻色子]]s。膨胀参数是[[pion]]能量/动量。<br />
*For [[hadron]]s containing one heavy [[quark]] (such as the [[bottom quark|bottom]] or [[Charm quark|charm]]), an effective field theory which expands in powers of the quark mass, called the [[heavy quark effective theory]] (HQET), has been found useful.<br />
对于含有一个重的[[夸克]]的[[强子]]s(例如[[底夸克|底]]或[[魅力夸克|魅力]]),一种以夸克质量为幂展开的有效场理论,称为[[重夸克有效理论](HQET)。<br />
*For [[hadron]]s containing two heavy quarks, an effective field theory which expands in powers of the [[relative velocity]] of the heavy quarks, called [[non-relativistic QCD]] (NRQCD), has been found useful, especially when used in conjunctions with [[lattice QCD]].<br />
*对于含有两个重夸克的[[强子]],一种有效场理论被认为是有用的,它以重夸克的[[相对速度]]的幂次展开,称为[[非相对论性QCD]](NRQCD),特别是在与[[晶格QCD]]结合时。 <br />
*For [[hadron]] reactions with light energetic ([[collinear]]) particles, the interactions with low-energetic (soft) degrees of freedom are described by the [[soft-collinear effective theory]] (SCET).<br />
对于与光能([[共线]])粒子的[[强子]]反应,用[[软共线有效理论]](SCET)描述了与低能(软)自由度的相互作用。 <br />
*Much of [[condensed matter physics]] consists of writing effective field theories for the particular property of matter being studied.<br />
*许多[[凝聚态物理]]都是为所研究的物质的特殊性质写有效的场理论。<br />
*[[Hydrodynamics]] can also be treated using Effective Field Theories<ref>{{Cite journal |arxiv = 1211.6461|last1 = Endlich|first1 = Solomon|title = Dissipation in the effective field theory for hydrodynamics: First order effects|journal = Physical Review D|volume = 88|issue = 10|pages = 105001|last2 = Nicolis|first2 = Alberto|last3 = Porto|first3 = Rafael|last4 = Wang|first4 = Junpu|year = 2013|doi = 10.1103/PhysRevD.88.105001|s2cid = 118441607}}</ref><br />
[流体力学]也可以使用有效场理论进行处理 <br />
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==See also参见==<br />
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*[[Form factor (quantum field theory)]]<br />
形状因子(量子场论)<br />
*[[Renormalization group]]<br />
重整化群 <br />
*[[Quantum field theory]]<br />
量子场论<br />
*[[Quantum triviality]]<br />
量子平凡性<br />
*[[Ginzburg–Landau theory]]<br />
金茨堡-兰道理论<br />
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==References参考==<br />
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{{Reflist}}<br />
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==External links外部链接==<br />
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*{{cite arxiv |eprint=hep-ph/9806303|last1=Birnholtz|first1=Ofek|title=Effective Field Theory|last2=Hadar|first2=Shahar|last3=Kol|first3=Barak|year=1998}}<br />
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*{{cite journal |doi=10.1016/S1355-2198(01)00005-3 |url=http://philsci-archive.pitt.edu/93/1/Hartmann.pdf|title=Effective Field Theories, Reductionism and Scientific Explanation|journal=Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics|volume=32|issue=2|pages=267–304|year=2001|last1=Hartmann|first1=Stephan}}<br />
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*{{Cite journal |arxiv=hep-ph/9703290|last1=Birnholtz|first1=Ofek|title=Aspects of Heavy Quark Theory|journal= Annual Review of Nuclear and Particle Science|volume=47|pages=591–661|last2=Hadar|first2=Shahar|last3=Kol|first3=Barak|year=1997|doi=10.1146/annurev.nucl.47.1.591|s2cid=13843227}}<br />
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*[http://www.fuw.edu.pl/~dobaczew/maub-42w/node18.html Effective field theory] (Interactions, Symmetry Breaking and Effective Fields - from Quarks to Nuclei. an Internet Lecture by Jacek Dobaczewski)<br />
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{{Industrial and applied mathematics}}<br />
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范畴: 量子场论<br />
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Category:Condensed matter physics<br />
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类别: 凝聚态物理学<br />
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<small>This page was moved from [[wikipedia:en:Effective field theory]]. Its edit history can be viewed at [[有效场论/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%9B%96%E4%BA%9A%E5%81%87%E8%AF%B4&diff=18464盖亚假说2020-11-16T09:21:55Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Hypothesis that living organisms interact with their surroundings in a self-regulating system}}<br />
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[[File:The Earth seen from Apollo 17.jpg|thumb|The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth]]'s conditions, as the Earth is the only planet currently known to harbour life (''[[The Blue Marble]]'', 1972 [[Apollo 17]] photograph)]]<br />
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The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth's conditions, as the Earth is the only planet currently known to harbour life (The Blue Marble, 1972 Apollo 17 photograph)]]<br />
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行星可居住性的研究部分基于对[[地球条件]的了解推断,因为地球是目前已知的唯一一颗拥有生命的行星 <br />
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The '''Gaia hypothesis''' {{IPAc-en|ˈ|ɡ|aɪ|.|ə}}, also known as the '''Gaia theory''' or the '''Gaia principle''', proposes that living [[organism]]s interact with their [[Inorganic compound|inorganic]] surroundings on [[Earth]] to form a [[Synergy|synergistic]] and [[Homeostasis|self-regulating]], [[complex system]] that helps to maintain and perpetuate the conditions for [[life]] on the planet.<br />
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The Gaia hypothesis , also known as the Gaia theory or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet.<br />
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盖亚假说(又称盖亚理论或盖亚原理)提出,生物体与地球上的无机环境相互作用,形成一个协同和自我调节的复杂系统,有助于维持和延续地球上的生命条件。<br />
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The hypothesis was formulated by the chemist [[James Lovelock]]<ref name="J1972" /> and co-developed by the microbiologist [[Lynn Margulis]] in the 1970s.<ref name="lovelock1974">{{cite journal|last1=Lovelock|first1=J.E.|last2=Margulis|first2=L.|title=Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis|journal=Tellus|date=1974|volume=26|series=Series A|issue=1–2|pages=2–10|doi=10.1111/j.2153-3490.1974.tb01946.x|publisher=International Meteorological Institute|location=Stockholm|issn=1600-0870|ref=harv|bibcode=1974Tell...26....2L}}</ref> Lovelock named the idea after [[Gaia]], the primordial goddess who personified the Earth in [[Greek mythology]]. In 2006, the [[Geological Society of London]] awarded Lovelock the [[Wollaston Medal]] in part for his work on the Gaia hypothesis.<ref>{{cite web|title=Wollaston Award Lovelock|url=https://www.geolsoc.org.uk/About/History/Awards-Citations-Replies-2001-Onwards/2006-Awards-Citations-Replies|accessdate=19 October 2015}}</ref><br />
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The hypothesis was formulated by the chemist James Lovelock Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis.<br />
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这个假设是由化学家詹姆斯 洛夫洛克提出的,他以希腊神话中地球的化身盖亚的名字命名了这个想法。2006年,伦敦地质学会授予洛夫洛克沃拉斯顿勋章,部分原因是他在<font color="#ff8000"> 盖亚假说Gaia hypothesis</font>方面的工作。 <br />
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Topics related to the hypothesis include how the [[biosphere]] and the [[evolution]] of organisms affect the stability of [[global temperature]], [[salinity]] of [[seawater]], [[atmospheric oxygen]] levels, the maintenance of a [[hydrosphere]] of liquid water and other environmental variables that affect the [[habitability of Earth]].<br />
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Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth.<br />
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与该假设有关的主题包括生物圈和生物体的进化如何影响全球温度的稳定性、海水的盐度、大气中的氧含量、液态水的水圈的维持以及其他影响地球宜居性的环境变量。<br />
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The Gaia hypothesis was initially criticized for being [[teleological]] and against the principles of [[natural selection]], but later refinements aligned the Gaia hypothesis with ideas from fields such as [[Earth system science]], [[biogeochemistry]] and [[systems ecology]].<ref name="Turney, Jon 2003"/><ref name="Schwartzman2002">{{cite book |author=Schwartzman, David |title=Life, Temperature, and the Earth: The Self-Organizing Biosphere |publisher=Columbia University Press |date=2002 |isbn=978-0-231-10213-1 }}</ref><ref>Gribbin, John (1990), "Hothouse earth: The greenhouse effect and Gaia" (Weidenfeld & Nicolson)</ref> Lovelock also once described the "geophysiology" of the Earth.<ref name="agesofgaia">Lovelock, James, (1995) "The Ages of Gaia: A Biography of Our Living Earth" (W.W.Norton & Co)</ref>{{Explain|date=December 2017}} Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<ref name="kirchner2002">{{Citation |last= Kirchner |first = James W. |title =Toward a future for Gaia theory |journal=[[Climatic Change (journal)|Climatic Change]] |volume = 52 |issue = 4 |pages = 391–408 |date = 2002 | doi = 10.1023/a:1014237331082 }}</ref><ref name="volk2002">{{Citation |last= Volk |first = Tyler |title =The Gaia hypothesis: fact, theory, and wishful thinking |journal = Climatic Change |volume = 52 |issue = 4 |pages = 423–430 |date = 2002 | doi = 10.1023/a:1014218227825 }}</ref><ref name="beerling2007">{{cite book |last=Beerling |first=David |authorlink=David Beerling|date=2007 |title=The Emerald Planet: How plants changed Earth's history |url=http://ukcatalogue.oup.com/product/9780192806024.do |location=Oxford|publisher=Oxford University Press |page= |isbn= 978-0-19-280602-4 |accessdate= }}</ref><br />
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The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Lovelock also once described the "geophysiology" of the Earth. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<br />
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盖亚假说最初被批评为目的论和反对自然选择的原则,但后来的改进使盖亚假说与来自地球系统科学、生物地球化学和系统生态学等领域的想法相一致。洛夫洛克还曾经描述过地球的“地球物理学”。即便如此,盖亚假说仍然受到批评,今天许多科学家认为它只有微弱的支持,或与现有的证据相矛盾。<br />
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==Overview总览==<br />
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Gaian hypotheses suggest that organisms [[Co-evolution|co-evolve]] with their environment: that is, they "influence their [[abiotic]] environment, and that environment in turn influences the [[Biota (ecology)|biota]] by [[Darwinism|Darwinian process]]". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early [[Bacteria|thermo-acido-philic]] and [[methanogenic bacteria]] towards the oxygen-enriched [[atmosphere]] today that supports more [[Phanerozoic|complex life]].<br />
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Gaian hypotheses suggest that organisms co-evolve with their environment: that is, they "influence their abiotic environment, and that environment in turn influences the biota by Darwinian process". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early thermo-acido-philic and methanogenic bacteria towards the oxygen-enriched atmosphere today that supports more complex life.<br />
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盖恩假说认为,生物体与其环境共同进化:也就是说,它们“影响它们的非生物环境,而环境反过来又通过达尔文的过程影响生物群”。Lovelock(1995)在他的第二本书中提供了证据,展示了从早期嗜酸和产甲烷细菌的世界向今天支持更复杂生命的富氧大气的进化。<br />
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A reduced version of the hypothesis has been called "influential Gaia"<ref name=":02">{{Cite journal|last=Lapenis|first=Andrei G.|year=2002|title=Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?|url=|journal=The Professional Geographer|volume=54 |issue=3|pages=379–391|via=[Peer Reviewed Journal]|doi=10.1111/0033-0124.00337}}</ref> in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the [[Biota (ecology)|biota]] influence certain aspects of the abiotic world, e.g. [[temperature]] and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<ref name=":02" /> and biogeochemical processes. An example is how the activity of [[Photosynthesis|photosynthetic]] bacteria during Precambrian times completely modified the [[Earth's atmosphere|Earth atmosphere]] to turn it aerobic, and thus supports the evolution of life (in particular [[eukaryotic]] life).<br />
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A reduced version of the hypothesis has been called "influential Gaia" in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the biota influence certain aspects of the abiotic world, e.g. temperature and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<br />
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在《生物圈的定向进化: 生物地球化学选择还是盖亚? 》一书中,这一假说的简化版被称为“有影响力的盖亚”由安德烈·G·拉佩尼斯所著,他指出生物群影响着非生物世界的某些方面,例如:温度和大气。这不是一个人的工作,而是一个俄罗斯科学研究的集体,合并成这个同行评议的出版物。它通过“微观力量”阐述了生命与环境的共同进化<br />
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Since barriers existed throughout the twentieth century between Russia and the rest of the world, it is only relatively recently that the early Russian scientists who introduced concepts overlapping the Gaia hypothesis have become better known to the Western scientific community.<ref name=":02" /> These scientists include [[Piotr Kropotkin|Piotr Alekseevich Kropotkin]] (1842–1921) (although he spent much of his professional life outside Russia), Vasil’evich Rizpolozhensky (1847–1918), [[Vladimir Ivanovich Vernadsky]] (1863–1945), and Vladimir Alexandrovich Kostitzin (1886–1963).<br />
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由于二十世纪俄罗斯与世界其他地区之间存在着隔阂,直到最近,引进了盖亚假说重叠概念的早期俄罗斯科学家才为西方科学界所熟知 <br />
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The Gaia hypothesis posits that the Earth is a self-regulating complex system involving the biosphere, the atmosphere, the hydrospheres and the pedosphere, tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<br />
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盖亚假说认为,地球是一个自我调节的复杂系统,包括生物圈、大气层、水圈和土壤圈,作为一个进化的系统紧密结合在一起。这个假说认为,这个被称为盖亚的系统作为一个整体,寻求一个适合当代生命的物理和化学环境。<br />
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Biologists and Earth scientists usually view the factors that stabilize the characteristics of a period as an undirected [[emergent property]] or [[entelechy]] of the system; as each individual species pursues its own self-interest, for example, their combined actiYons may have counterbalancing effects on environmental change. Opponents of this view sometimes reference examples of events that resulted in dramatic change rather than stable equilibrium, such as the conversion of the Earth's atmosphere from a [[reducing environment]] to an [[oxygen]]-rich one at the end of the [[Archean|Archaean]] and the beginning of the [[Proterozoic]] periods.<br />
生物学家和地球科学家通常将稳定一个时期特征的因素视为系统的一个无方向的[[涌现属性]]或[[有目的行为]];例如,由于每个物种都追求自身利益,它们的联合行动可能对环境变化产生抵消作用。反对这一观点的人有时会举出一些事件的例子,这些事件导致了巨大的变化,而不是稳定的平衡,例如在[[太古宙|太古代]]末期和[[元古代]]时期开始时,地球大气从[[还原环境]]转变为富含[[氧气]]。 <br />
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Gaia evolves through a cybernetic feedback system operated unconsciously by the biota, leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially microorganisms, with inorganic elements. These processes establish a global control system that regulates Earth's surface temperature, atmosphere composition and ocean salinity, powered by the global thermodynamic disequilibrium state of the Earth system.<!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
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盖亚通过一个由生物群无意识操作的控制论反馈系统进化,在一个完全的内稳态中达成可居住条件的广泛稳定。地球表面的许多过程对生命的条件至关重要,这些过程依赖于生命形式,特别是微生物与无机元素的相互作用。这些过程建立了一个全球控制系统,由地球系统的全球热力学不平衡状态提供动力,调节地球表面温度、大气成分和海洋盐度。<br />
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Less accepted versions of the hypothesis claim that changes in the biosphere are brought about through the [[Superorganism|coordination of living organisms]] and maintain those conditions through [[homeostasis]]. In some versions of [[Gaia philosophy]], all lifeforms are considered part of one single living planetary being called ''Gaia''. In this view, the atmosphere, the seas and the terrestrial crust would be results of interventions carried out by Gaia through the [[Coevolution|coevolving]] diversity of living organisms.<br />
不太被接受的假说声称生物圈的变化是通过[[超级有机体|生物体的协调]]来实现的,并通过[[内稳态]]来维持这些条件。在一些版本的[[盖亚哲学]]中,所有的生命形式都被认为是一个被称为“盖亚”的生命行星的一部分。在这种观点下,大气、海洋和地壳将是盖亚通过生物多样性进行干预的结果。 <br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of biogeochemistry, and it is being investigated also in other fields like Earth system science. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<br />
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以前在生物地球化学领域已经观察到受生命形式影响的行星内稳态的存在,而且在地球系统科学等其他领域也在研究这一现象。盖亚假说的原创性依赖于这样一种评估: 即使地球或外部事件威胁到这种平衡,这种平衡也是为了保持生命的最佳状态而积极追求的。<br />
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The Gaia hypothesis was an influence on the [[deep ecology]] movement.<ref>David Landis Barnhill, Roger S. Gottlieb (eds.), ''Deep Ecology and World Religions: New Essays on Sacred Ground'', SUNY Press, 2010, p. 32.</ref><br />
盖亚假说对[[深层生态学]]运动产生了影响 <br />
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==Details细节==<br />
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Rob Rohde's palaeotemperature graphs<br />
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罗布·罗德的古温度图<br />
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The Gaia hypothesis posits that the Earth is a self-regulating [[complex system]] involving the [[biosphere]], the [[Earth's atmosphere|atmosphere]], the [[hydrosphere]]s and the [[pedosphere]], tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<ref name="vanishing255">Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 255. {{ISBN|978-0-465-01549-8}}</ref><br />
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盖亚假说假设地球是一个自我调节的[[复杂系统]],包括[[生物圈]]、[[地球大气|大气]]、[[水圈]]和[[土壤圈]],作为一个进化系统紧密耦合。该假说认为,这个系统作为一个整体,称为盖亚,寻求一个最适合当代生活的物理和化学环境 <br />
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Since life started on Earth, the energy provided by the Sun has increased by 25% to 30%; however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on Titan. research has suggested that "oxygen shocks" and reduced methane levels led, during the Huronian, Sturtian and Marinoan/Varanger Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre Phanerozoic biosphere to fully self-regulate.<br />
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自从地球上有生命以来,太阳提供的能量增加了25%到30%;然而,地球表面温度一直保持在适宜居住的水平上,达到了相当规律的高低边缘。洛夫洛克还假设,产甲烷菌在早期大气中产生了较高水平的甲烷,这与在石化烟雾中发现的观点相似,在某些方面与土卫六上的大气相似。研究表明,在休伦期、斯图尔特期和马里诺/瓦朗格冰期,“氧冲击”和甲烷含量降低导致世界几乎变成了一个坚实的“雪球”。这些时代是前显生宙生物圈完全自我调节能力的证据。<br />
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Gaia evolves through a [[Cybernetic#In biology|cybernetic]] [[feedback]] system operated unconsciously by the [[biota (ecology)|biota]], leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially [[microorganisms]], with inorganic elements. These processes establish a global control system that regulates Earth's [[Sea surface temperature|surface temperature]], [[atmosphere composition]] and [[ocean]] [[salinity]], powered by the global thermodynamic disequilibrium state of the Earth system.<ref>Kleidon, Axel. ''How does the earth system generate and maintain thermodynamic disequilibrium and what does it imply for the future of the planet?''. Article submitted to the ''Philosophical Transactions of the Royal Society'' on Thu, 10 Mar 2011</ref><!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
盖亚通过一个[[控制论|生物学|控制论]][[反馈]]系统在[[生物群(生态学)|生物群]]的无意识运作中进化,导致在完全的内稳态中可居住条件的广泛稳定。地球表面对生命条件至关重要的许多过程都依赖于生物,特别是[微生物]与无机元素的相互作用。这些过程建立了一个全球控制系统,调节地球的[[海表温度|表面温度]]、[[大气组成]]和[[海洋]][[盐度]],其动力来自地球系统的全球热力学不平衡状态。<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
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说明了处理温室气体CO2在维持地球温度在可居住范围内起着关键作用。<br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of [[biogeochemistry]], and it is being investigated also in other fields like [[Earth system science]]. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 179. {{ISBN|978-0-465-01549-8}}</ref><br />
受生命形式影响的行星内稳态的存在,以前在[[生物地球化学]]领域就已被观察到,而且在其他领域,如[[地球系统科学]]也在研究中。盖亚假说的独创性依赖于这样一种评估,即积极追求这种体内平衡,以保持生命的最佳状态,即使是在地球或外部事件威胁它们的时候。<br />
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The CLAW hypothesis, inspired by the Gaia hypothesis, proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative feedback loop that acts to stabilise the temperature of the Earth's atmosphere.<br />
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受盖亚假说的启发,CLAW 假说提出了一个在海洋生态系统和地球气候之间运行的反馈回路。该假说特别提出,产生二甲硫醚的浮游植物对气候强迫的变化有反应,这些反应导致了一个负反馈循环,稳定了地球大气的温度。<br />
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===Regulation of global surface temperature地球表面温度的调控===<br />
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[[File:All palaeotemps.png|thumb|480px|Rob Rohde's palaeotemperature graphs]]<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of greenhouse gases may cause negative feedbacks in the environment to become positive feedback. Lovelock has stated that this could bring an extremely accelerated global warming, but he has since stated the effects will likely occur more slowly.<br />
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目前,人口的增加及其活动对环境的影响,例如温室气体的增加,可能导致环境中的负反馈成为正反馈。洛夫洛克表示,这可能会极大地加速全球变暖,但他后来又表示,这种影响可能会发生得更慢。<br />
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{{See also|Paleoclimatology}}<br />
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Since life started on Earth, the energy provided by the [[Sun]] has increased by 25% to 30%;<ref name="Owen1979">{{cite journal | author = Owen, T. | author2 = Cess, R.D. | author3 = Ramanathan, V. | date = 1979 | title = Earth: An enhanced carbon dioxide greenhouse to compensate for reduced solar luminosity | journal = [[Nature (journal)|Nature]] | volume = 277 | pages = 640–2 | doi = 10.1038/277640a0 | issue=5698 | bibcode = 1979Natur.277..640O | ref = harv }}</ref> however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on [[Titan (moon)|Titan]].<ref name="agesofgaia"/> This, he suggests tended to screen out ultraviolet until the formation of the ozone screen, maintaining a degree of homeostasis. However, the [[Snowball Earth]]<ref>Hoffman, P.F. 2001. [http://www.snowballearth.org ''Snowball Earth theory'']</ref> research has suggested that "oxygen shocks" and reduced methane levels led, during the [[Huronian]], [[Sturtian]] and [[Marinoan]]/[[Cryogenian|Varanger]] Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre [[Phanerozoic]] biosphere to fully self-regulate.<br />
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Plots from a standard black and white [[Daisyworld simulation]]<br />
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从一个标准的黑白图[[雏菊世界模拟]]<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
说明了在温室气体维持低于临界温度的过程中,CO2起着至关重要的作用。 <br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic group selection and cooperation between organisms, James Lovelock and Andrew Watson developed a mathematical model, Daisyworld, in which ecological competition underpinned planetary temperature regulation.<br />
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有人批评盖亚假说似乎需要不切实际的群体选择和有机体之间的合作,为了回应这种批评,James Lovelock 和 Andrew Watson建立了一个数学模型---- 雏菊世界,其中生态竞争支撑着地。<br />
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The [[CLAW hypothesis]], inspired by the Gaia hypothesis, proposes a [[feedback|feedback loop]] that operates between [[ocean]] [[ecosystem]]s and the [[Earth]]'s [[climate]].<ref name="CLAW87">{{cite journal |doi=10.1038/326655a0 |author=[[Robert Jay Charlson|Charlson, R. J.]], [[James Lovelock|Lovelock, J. E]], Andreae, M. O. and Warren, S. G. |title=Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate |journal=Nature |volume=326 |issue=6114 |pages=655–661 |date=1987 |bibcode=1987Natur.326..655C |ref=harv }}</ref> The [[hypothesis]] specifically proposes that particular [[phytoplankton]] that produce [[dimethyl sulfide]] are responsive to variations in [[climate forcing]], and that these responses lead to a [[negative feedback|negative feedback loop]] that acts to stabilise the [[temperature]] of the [[Earth's atmosphere]].<br />
受到盖亚假说启发的[[爪假说]]提出了一个在[[海洋]][[生态系统]]和[[地球]]的[[气候]]之间运行的[[反馈|反馈回路]]。<br />
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Daisyworld examines the energy budget of a planet populated by two different types of plants, black daisies and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the albedo of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
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《雏菊世界》调查了一个星球的能量预算,这个星球上生长着两种不同的植物,黑色雏菊和白色雏菊,这两种植物被认为占据了星球表面的很大一部分。雏菊的颜色影响了地球的反照率,黑色的雏菊吸收更多的光线,使地球变暖,而白色的雏菊则反射更多的光线,使地球变冷。人们认为黑色雏菊在较低的温度下生长和繁殖最好,而白色雏菊则被认为在较高的温度下生长最好。当温度上升到接近白色雏菊所喜欢的温度时,白色雏菊伸展出黑色雏菊,导致更大比例的白色表面,更多的阳光被反射,减少热量输入,最终使地球降温。相反,随着气温的下降,黑色雏菊长出了白色雏菊,吸收了更多的阳光,使地球变暖。因此,温度会收敛到与植物繁殖率相等的值。<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of [[greenhouse gases]] may cause [[negative feedback]]s in the environment to become [[positive feedback]]. Lovelock has stated that this could bring an [[James Lovelock#The revenge of Gaia|extremely accelerated global warming]],<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, {{ISBN|978-0-465-01549-8}}</ref> but he has since stated the effects will likely occur more slowly.<ref>Lovelock J., NBC News. [http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite Link] Published 23 April 2012, accessed 22 August 2012. {{Webarchive|url=https://web.archive.org/web/20120913163635/http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite |date=13 September 2012 }}</ref><br />
目前,人口的增加及其活动对环境的影响,如[[温室气体]]的倍增,可能导致环境中的[[负反馈]]变成[[正反馈]]。洛夫洛克曾表示,这可能会带来一场【【James Loveloc【《盖亚的复仇』极度加速的全球变暖】】 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this negative feedback due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
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洛夫洛克和沃森指出,在有限的条件下,如果太阳的能量输出发生变化,由于竞争而产生的负反馈可以将地球温度稳定在支持生命的数值上,而没有生命的地球则会表现出巨大的温度波动。白色和黑色雏菊的百分比会不断变化,以保持植物繁殖率相等的温度值,使两种生命形式都能茁壮成长。<br />
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====Daisyworld simulations雏菊世界模拟====<br />
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[[File:StandardDaisyWorldRun2color.gif|thumb|280px|Plots from a standard black and white [[Daisyworld]] simulation]]<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<br />
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有人认为,这些结果是可以预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的答案。<br />
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{{Main|Daisyworld}}<br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic [[group selection]] and [[Cooperation (evolution)|cooperation]] between organisms, James Lovelock and [[Andrew Watson (scientist)|Andrew Watson]] developed a mathematical model, [[Daisyworld]], in which [[Competition (biology)|ecological competition]] underpinned planetary temperature regulation.<ref name="daisyworld">{{cite journal<br />
有人批评盖亚假说似乎需要有机体之间不切实际的[[群体选择]]和[[合作(进化)|合作]],詹姆斯·洛夫洛克和[[安德鲁·沃森(科学家)|安德鲁·沃森]]开发了一个数学模型,[[雏菊世界]],其中[[竞争(生物学)|生态竞争]]为基础行星温度调节。 <br />
|date = 1983<br />
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Ocean salinity has been constant at about 3.5% for a very long time. Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested that salinity may also be strongly influenced by seawater circulation through hot basaltic rocks, and emerging as hot water vents on mid-ocean ridges. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<br />
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长期以来,海洋盐度一直保持在3.5% 左右。海洋环境中盐度的稳定性很重要,因为大多数细胞需要相当恒定的盐度,一般不能容忍超过5% 的盐度值。恒定的海洋盐度是一个长期存在的秘密,因为没有任何方法可以抵消来自河流的盐的流入。最近有人提出,盐度也可能受到穿过炽热玄武岩的海水循环的强烈影响,并在洋中脊上出现热水喷口。然而,海水的组成离平衡还很远,如果没有有机过程的影响,很难解释这一事实。有一种解释认为,地球历史上盐原的形成是原因之一。据推测,这些是由细菌菌落产生的,它们在生命过程中固定离子和重金属。<br />
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|title = Biological homeostasis of the global environment: the parable of Daisyworld<br />
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|journal = Tellus<br />
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|volume = 35B<br />
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Vostok, Antarctica research station. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
沃斯托克,南极洲研究站。当前期间在左边。<!--基于此图表的GIMP-FX版本的非源材料。现在的版本是正确的,原版的。必须删除这句话:请注意,当前CO2水平超过390ppm,远高于过去40万年来的任何时候-->] <br />
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|pages = 286–9<br />
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|bibcode = 1983TellB..35..284W<br />
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|doi = 10.1111/j.1600-0889.1983.tb00031.x<br />
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The Gaia hypothesis states that the Earth's atmospheric composition is kept at a dynamically steady state by the presence of life. The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than noble gases present in the atmosphere are either made by organisms or processed by them.<br />
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盖亚假说认为,地球的大气组成是由于生命的存在而保持在动态稳定的状态。大气成分提供了现代生活已经适应的条件。大气中除惰性气体以外的所有大气气体,要么是由生物体产生的,要么是由生物体加工的。<br />
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|last1 = Watson | first1= A.J. | last2= Lovelock | first2= J.E<br />
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|issue = 4<br />
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The stability of the atmosphere in Earth is not a consequence of chemical equilibrium. Oxygen is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the Great Oxygenation Event. Since the start of the Cambrian period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume. Traces of methane (at an amount of 100,000 tonnes produced per year) should not exist, as methane is combustible in an oxygen atmosphere.<br />
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地球大气层的稳定性不是化学平衡的结果。氧是一种活性化合物,最终会与地球大气层和地壳中的气体和矿物质结合。在大氧化事件空间站开始之前,大约5000万年左右,氧气才开始在大气中少量地持续存在。自寒武纪以来,大气中氧浓度一直在大气体积的15% 至35% 之间波动。微量的甲烷(每年产生100,000吨)不应该存在,因为甲烷在氧气氛中是可燃的。<br />
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|ref = harv<br />
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}}</ref><br />
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Dry air in the atmosphere of Earth contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases including methane. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. <br />
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地球大气层中的干燥空气大致(按体积计算)含有78.09% 的氮气、20.95% 的氧气、0.93% 的氩气、0.039% 的二氧化碳以及少量的其他气体,包括甲烷。洛夫洛克最初推测,高于25% 的氧气浓度会增加森林大火和森林大火的发生频率。最近在石炭纪和白垩纪煤系地质时期,当O2确实超过了25%时,火成木炭的研究结果支持了 Lovelock 的论点。<br />
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Daisyworld examines the [[Earth's energy budget|energy budget]] of a [[planet]] populated by two different types of plants, black [[Asteraceae|daisies]] and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the [[albedo]] of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
Daisyworld研究了[[地球的能源预算|能源预算]]的[[地球的能源预算]]居住着两种不同类型的植物,黑色的[[菊科的雏菊]]和白色的雏菊,这两种植物被认为占据了地表的很大一部分。雏菊的颜色影响着这个星球的[反照率],因此黑色雏菊吸收更多的光并温暖地球,而白色雏菊则反射更多的光并使地球降温。黑雏菊在较低温度下生长繁殖最好,而白雏菊在较高温度下生长繁殖最好。当温度上升到接近白色雏菊的数值时,白色雏菊的繁殖能力超过了黑色雏菊,导致白色表面的比例增大,更多的阳光被反射,减少了热量输入,最终使地球变冷。相反,随着温度的下降,黑雏菊的繁殖能力超过了白雏菊,吸收了更多的阳光,使地球变暖。因此,温度将收敛到植物繁殖率相等的值。 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this [[negative feedback]] due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
Lovelock和Watson表明,在有限的条件范围内,如果太阳的能量输出发生变化,由于竞争而产生的[[负面反馈]]可以将地球的温度稳定在支持生命的值上,而没有生命的行星则会出现大范围的温度波动。白雏菊和黑雏菊的比例会不断变化,以使温度保持在植物繁殖率相等的值,从而使两种生命形式都能茁壮成长。 <br />
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Gaia scientists see the participation of living organisms in the carbon cycle as one of the complex processes that maintain conditions suitable for life. The only significant natural source of atmospheric carbon dioxide (CO<sub>2</sub>) is volcanic activity, while the only significant removal is through the precipitation of carbonate rocks. Carbon precipitation, solution and fixation are influenced by the bacteria and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
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盖亚假说的科学家们把生物体参与碳循环看作是维持适合生命条件的复杂过程之一。火山活动是大气中二氧化碳的唯一重要自然来源,而碳酸盐岩的沉淀是大气中二氧化碳唯一重要的去除途径。碳沉淀、溶解和固定受到土壤中细菌和植物根系的影响,这些细菌和植物根系可以改善气体循环,或者在珊瑚礁中,碳酸钙以固体的形式沉积在海底。碳酸钙被活的有机体用来制造含碳的试验和外壳。一旦死亡,生物体的外壳就会沉到海底,在那里它们产生白垩和石灰石的沉淀物。<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<ref>{{cite journal | doi = 10.1023/A:1023494111532 | date = 2003 | last1 = Kirchner | first1 = James W. | journal = Climatic Change | volume = 58 |issue=1–2| pages = 21–45 |title=The Gaia Hypothesis: Conjectures and Refutations | ref = harv}}</ref><br />
有人认为,结果是可预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的反应。 <br />
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One of these organisms is Emiliania huxleyi, an abundant coccolithophore algae which also has a role in the formation of clouds. CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants. Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean algal blooms are also increasing.<br />
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其中一种是赫氏圆石藻,这是一种数量丰富的颗石藻类,也参与了云的形成。CO < sub > 2 </sub > 过量通过增加球石氟化物的寿命来补偿,增加了锁定在海底的 CO < sub > 2 </sub > 的数量。球石粉会增加云量,从而控制地表温度,有助于降低整个地球的温度,有利于地球上植物所必需的降水。近年来,大气中 CO < < sub > 2 </sub > 浓度有所增加,有证据表明,海洋藻华的浓度也在增加。<br />
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===Regulation of oceanic salinity海洋盐度调节 ===<br />
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Lichen and other organisms accelerate the weathering of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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地衣和其他生物加速了岩石表面的风化,而岩石在土壤中的分解也加快了,这要归功于根、真菌、细菌和地下动物的活动。因此,二氧化碳从大气层流向土壤的过程是在生物的帮助下进行调节的。当大气中 CO2水平升高时,温度升高,植物生长。这种生长会增加植物对二氧化碳的消耗,植物会将二氧化碳处理到土壤中,从大气中排出。<br />
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Ocean [[salinity]] has been constant at about 3.5% for a very long time.<ref name=":0">{{Cite book|title=The Introduction to Ocean Sciences|last=Segar|first=Douglas|publisher=Library of Congress|year=2012|isbn=978-0-9857859-0-1|location=http://www.reefimages.com/oceans/SegarOcean3Chap05.pdf|pages=Chapter 5 3rd Edition|quote=|via=}}</ref> Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested<ref name="Gorham19912">{{cite journal|last=Gorham|first=Eville|date=1 January 1991|title=Biogeochemistry: its origins and development|journal=Biogeochemistry|publisher=Kluwer Academic|volume=13|issue=3|pages=199–239|doi=10.1007/BF00002942|issn=1573-515X|ref=harv}}</ref> that salinity may also be strongly influenced by [[seawater]] circulation through hot [[basalt]]ic rocks, and emerging as hot water vents on [[mid-ocean ridge]]s. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<ref name=":0" /><br />
在很长一段时间内,海洋盐度一直保持在3.5%左右。[23]海洋环境中的盐度稳定性非常重要,因为大多数细胞需要相当恒定的盐度,并且通常不能容忍超过5%的盐度值。恒定的海洋盐度是一个长期存在的谜团,因为没有任何过程可以抵消河流中的盐流入。最近有人认为[24]海水通过热玄武质岩石时也会受到海水循环的强烈影响,并在大洋中脊上出现热水喷口。然而,海水的组成远未达到平衡,如果没有有机过程的影响,很难解释这一事实。一个建议的解释是,在整个地球的历史中,盐平原的形成。据推测,这些细菌是由在生命过程中固定离子和重金属的菌落产生的<br />
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In the biogeochemical processes of Earth, sources and sinks are the movement of elements. The composition of salt ions within our oceans and seas is: sodium (Na<sup>+</sup>), chlorine (Cl<sup>−</sup>), sulfate (SO<sub>4</sub><sup>2−</sup>), magnesium (Mg<sup>2+</sup>), calcium (Ca<sup>2+</sup>) and potassium (K<sup>+</sup>). The elements that comprise salinity do not readily change and are a conservative property of seawater.<ref name=":0" /> There are many mechanisms that change salinity from a particulate form to a dissolved form and back. The known sources of sodium i.e. salts are when weathering, erosion, and dissolution of rocks are transported into rivers and deposited into the oceans.<br />
在地球的生物地球化学过程中,源和汇是元素的运动。我们海洋中盐离子的组成是:钠(Na+)、氯(Cl-)、硫酸盐(SO42-)、镁(Mg2+)、钙(Ca2+)和钾(K+)。构成盐度的元素不易变化,是海水的一种保守属性。[23]有许多机制可以将盐度从颗粒形态改变为溶解形态,然后再返回。已知的钠(即盐)来源于岩石的风化、侵蚀和溶解作用被输送到河流中并沉积到海洋中。 <br />
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The [[Mediterranean Sea]] as being Gaia's kidney is found ([http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/ here]) by Kenneth J. Hsue, a correspondence author in 2001. The "[[desiccation]]" of the Mediterranean is the evidence of a functioning kidney. Earlier "kidney functions" were performed during the "[[Deposition (geology)|deposition]] of the [[Cretaceous]] ([[Atlantic Ocean|South Atlantic]]), [[Jurassic]] ([[Gulf of Mexico]]), [[Permian–Triassic extinction event|Permo-Triassic]] ([[Europe]]), [[Devonian]] ([[Canada]]), [[Cambrian]]/[[Precambrian]] ([[Gondwana]]) saline giants."<ref>{{Cite web|url=http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/|title=Scientia Marina: List of Issues|last=http://www.webviva.com|first=Justino Martinez. Web Viva 2007|website=scimar.icm.csic.es|language=English|access-date=2017-02-04}}</ref><br />
地中海是盖亚的肾脏,由肯尼斯·J·休伊(KennethJ.Hsue)在2001年发现的。地中海的“干涸”是肾功能正常的证据。早期的“肾功能”是在“白垩纪(南大西洋)、侏罗纪(墨西哥湾)、二叠纪-三叠纪(欧洲)、泥盆纪(加拿大)、寒武纪/前寒武纪(冈瓦纳)盐沼沉积时期进行的。” <br />
[[Earthrise taken from Apollo 8 on December 24, 1968]]<br />
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[1968年12月24日阿波罗8号拍摄的地出]<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The mythical Gaia was the primal Greek goddess personifying the Earth, the Greek version of "Mother Nature" (from Ge = Earth, and Aia = <br />
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地球作为一个完整的整体,一个有生命的存在,这个观念有着悠久的传统。神话中的盖亚是拟人化地球的原始希腊女神,是希腊版本的“自然母亲”(来自 Ge = 地球,和 Aia = <br />
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===Regulation of oxygen in the atmosphere大气层的氧气调节===<br />
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PIE grandmother), or the Earth Mother. James Lovelock gave this name to his hypothesis after a suggestion from the novelist William Golding, who was living in the same village as Lovelock at the time (Bowerchalke, Wiltshire, UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry. Later, the naturalist and explorer Alexander von Humboldt recognized the coevolution of living organisms, climate, and Earth's crust. His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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派祖母,或地球母亲。詹姆斯·洛夫洛克根据小说家威廉·戈尔丁的建议给他的假设起了这个名字,他当时和洛夫洛克住在同一个村子里(英国威尔特郡鲍尔查尔克)。戈尔丁的建议是以Gea为基础的,Gea是希腊女神名字的另一种拼写,在地质学、地球物理和地球化学中,Gea是前缀。后来,博物学家和探险家亚历山大·冯·洪堡认识到生物、气候和地壳的共同进化。他的远见卓识的声明在西方没有被广泛接受,几十年后,盖亚假说受到了科学界同样类型的最初抵制。<br />
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[[File:Vostok 420ky 4curves insolation.jpg|thumb|280px|Levels of gases in the atmosphere in 420,000 years of ice core data from [[Vostok Station|Vostok, Antarctica research station]]. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
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{{See also|Geological history of oxygen}}<br />
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Also in the turn to the 20th century Aldo Leopold, pioneer in the development of modern environmental ethics and in the movement for wilderness conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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同样在20世纪之交,现代环境伦理学发展的先驱、荒野保护运动的先驱奥尔多 · 利奥波德在他的生物中心或整体的土地伦理学中提出了一个有生命的地球。<br />
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The Gaia hypothesis states that the Earth's [[Atmospheric chemistry#Atmospheric composition|atmospheric composition]] is kept at a dynamically steady state by the presence of life.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 163. {{ISBN|978-0-465-01549-8}}</ref> The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than [[noble gas]]es present in the atmosphere are either made by organisms or processed by them.<br />
盖亚假说指出,地球的大气成分由于生命的存在而保持在动态稳定的状态。大气中除惰性气体以外的所有大气气体都是由生物体制造或加工而成。<br />
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The stability of the atmosphere in Earth is not a consequence of [[chemical equilibrium]]. [[Oxygen]] is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the [[Great Oxygenation Event]].<ref name=Anabar2007>{{Cite journal| last4 = Arnold| last6 = Creaser| last3 = Lyons| first1 = A. | first2 = Y.| last9 = Scott| last2 = Duan | first3 = T. | first4 = G.| last8 = Gordon | first5 = B. | first10 = J. | first6 = R.| last10 = Garvin | first7 = A.| last11 = Buick | first8 = G. | first11 = R. | first9 = C.| title = A whiff of oxygen before the great oxidation event?| journal = Science| volume = 317| issue = 5846| year = 2007| last7 = Kaufman| pages = 1903–1906| last5 = Kendall| pmid = 17901330| last1 = Anbar | doi = 10.1126/science.1140325|bibcode = 2007Sci...317.1903A }}</ref> Since the start of the [[Cambrian]] period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume.<ref name=Berner1999>{{Cite journal<br />
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Another influence for the Gaia hypothesis and the environmental movement in general came as a side effect of the Space Race between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph Earthrise taken by astronaut William Anders in 1968 during the Apollo 8 mission became, through the Overview Effect an early symbol for the global ecology movement.<br />
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盖亚假说和环境运动的另一个影响来自于苏联和美利坚合众国之间太空竞赛的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球作为一个整体的样子。1968年,宇航员威廉 · 安德斯在阿波罗8号任务期间拍摄的地出照片,通过总体效应成为全球生态运动的早期象征。<br />
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| pmid = 10500106<br />
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| date=Sep 1999 | last1 = Berner | first1 = R. A.<br />
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| title = Atmospheric oxygen over Phanerozoic time<br />
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[[James Lovelock, 2005]]<br />
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[ James Lovelock,2005]<br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the Jet Propulsion Laboratory in California on methods of detecting life on Mars. The first paper to mention it was Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life, co-authored with C.E. Giffin. A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the Pic du Midi observatory, planets like Mars or Venus had atmospheres in chemical equilibrium. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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65年9月,洛夫洛克在加利福尼亚喷气推进实验室研究探测火星生命的方法时,开始定义由生物群落控制的自我调节地球的概念。第一篇提到它的论文是行星大气:与C.E.Giffin合著的与生命存在有关的成分和其他变化。一个主要的概念是,通过大气的化学成分可以在行星尺度上探测到生命。根据picdumidi天文台收集的数据,像火星或金星这样的行星,其大气层处于化学平衡状态。这种与地球大气的差异被认为是这些行星上没有生命的证据。 <br />
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Lovelock formulated the Gaia Hypothesis in journal articles in 1972 and 1974, and a popular book length version of the hypothesis, published in 1979 as The Quest for Gaia, began to attract scientific and critical attention.<br />
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洛夫洛克在1972年和1974年的期刊文章中提出了盖亚假说,并在1979年出版了一本畅销书,名为《寻找盖亚》 ,开始引起科学界和批判界的关注。<br />
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Lovelock called it first the Earth feedback hypothesis, and it was a way to explain the fact that combinations of chemicals including oxygen and methane persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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洛夫洛克首先将其称为地球反馈假说,这是一种解释包括氧气和甲烷在内的化学物质在地球大气中保持稳定浓度的方法。洛夫洛克认为,在其他行星的大气层中探测这种组合,是一种相对可靠和廉价的探测生命的方法。<br />
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| doi = 10.1073/pnas.96.20.10955<br />
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[[Lynn Margulis]]<br />
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|bibcode = 1999PNAS...9610955B }}</ref> Traces of [[Atmospheric methane|methane]] (at an amount of 100,000 tonnes produced per year)<ref name="Cicerone1988">{{cite journal |last1=Cicerone |first1=R.J. |last2=Oremland |first2=R.S. |date=1988 |title=Biogeochemical aspects of atmospheric methane |journal=Global Biogeochemical Cycles |volume=2 |issue=4 |pages=299–327 |url=//webfiles.uci.edu/setrumbo/public/Methane_papers/Cicerone_Global%20Biogeochem%20Cy_1988.pdf |doi=10.1029/GB002i004p00299 |bibcode=1988GBioC...2..299C}}</ref> should not exist, as methane is combustible in an oxygen atmosphere.<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<br />
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后来出现了其他关系,例如海洋生物产生的硫和碘的数量与陆地生物所需的数量大致相同,这些都支持了这一假说。<br />
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Dry air in the [[atmosphere of Earth]] contains roughly (by volume) 78.09% [[nitrogen]], 20.95% oxygen, 0.93% [[argon]], 0.039% [[Carbon dioxide in the Earth's atmosphere|carbon dioxide]], and small amounts of other gases including [[methane]]. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. {{citation needed|date=June 2012}}<br />
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[[地球大气]]中的干空气大约(按体积)包含78.09%[[氮]],20.95%的氧,0.93%[[氩]],0.039%[地球大气中的二氧化碳|二氧化碳]],以及少量其他气体,包括[[甲烷]]。洛夫洛克最初推测,氧气浓度超过25%会增加森林火灾和火灾的发生率。最近在石炭纪和白垩纪煤系中发现的由火引起的木炭的研究,在地质时期O<sub>2</sub>超过25%,支持了Lovelock的观点 <br />
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In 1971 microbiologist Dr. Lynn Margulis joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet. The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of eukaryotic organelles and her contributions to the endosymbiotic theory, nowadays accepted. Margulis dedicated the last of eight chapters in her book, The Symbiotic Planet, to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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1971年,微生物学家 Lynn Margulis 博士加入了 Lovelock 的行列,努力将最初的假设充实为科学证明的概念,贡献了她关于微生物如何影响大气层和地球表面不同层次的知识。这位美国生物学家也唤醒了科学界的批评,因为她倡导真核细胞器起源的理论,以及她对美国共生发源学会的贡献,现在被接受了。玛格丽丝在她的书《共生星球》中将最后八章献给了盖亚。然而,她反对对盖亚的广泛拟人化,并强调盖亚“不是一个有机体” ,而是“有机体之间相互作用的一个新兴属性”。她将盖亚定义为“组成地球表面一个巨大生态系统的一系列相互作用的生态系统”。句号”。这本书最令人难忘的“口号”实际上是由马古利斯的一个学生打趣说的: “从太空看,盖亚只是共生而已。”。<br />
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===Processing of CO<sub>2</sub>二氧化碳处理===<br />
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{{See also|Carbon cycle}}<br />
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James Lovelock called his first proposal the Gaia hypothesis but has also used the term Gaia theory. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments and provided a number of useful predictions. In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating. The principal sponsor was the National Audubon Society. Speakers included James Lovelock, George Wald, Mary Catherine Bateson, Lewis Thomas, John Todd, Donald Michael, Christopher Bird, Thomas Berry, David Abram, Michael Cohen, and William Fields. Some 500 people attended.<br />
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詹姆斯 · 洛夫洛克称他的第一个提议为盖亚假说,但也使用了盖亚理论这个术语。洛夫洛克说,最初的提法是基于观察,但仍然缺乏科学的解释。盖亚假说从那以后得到了一些科学实验的支持,并提供了一些有用的预测。事实上,更广泛的研究证明了最初的假设是错误的,在这个意义上,不是生命本身,而是整个地球系统在调节。主要赞助者是奥杜邦学会。讲者包括 James Lovelock、 George Wald、 Mary Catherine Bateson、 Lewis Thomas、 John Todd、 Donald Michael、 Christopher Bird、 Thomas Berry、 David Abram、 Michael Cohen 和 William Fields。大约有500人参加。<br />
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Gaia scientists see the participation of living organisms in the [[carbon cycle]] as one of the complex processes that maintain conditions suitable for life. The only significant natural source of [[Carbon dioxide in Earth's atmosphere|atmospheric carbon dioxide]] ([[Carbon dioxide|CO<sub>2</sub>]]) is [[volcanic activity]], while the only significant removal is through the precipitation of [[carbonate rocks]].<ref name="Karhu1996">{{cite journal | author = Karhu, J.A. | author2 = Holland, H.D. | date = 1 October 1996 | title = Carbon isotopes and the rise of atmospheric oxygen | journal = [[Geology (journal)|Geology]] | volume = 24 | issue = 10 | pages = 867–870 | doi = 10.1130/0091-7613(1996)024<0867:CIATRO>2.3.CO;2|bibcode = 1996Geo....24..867K | ref = harv}}</ref> Carbon precipitation, solution and [[Carbon fixation|fixation]] are influenced by the [[bacteria]] and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
盖亚的科学家认为,生物参与[[碳循环]是维持适宜生命条件的复杂过程之一。[[地球大气中的二氧化碳|大气二氧化碳]]([[二氧化碳| CO2]])的唯一重要自然来源是[[火山活动]],而唯一显著的清除是通过[[碳酸盐岩]]的沉淀,溶液和[[固碳|固碳]]受土壤中的[[细菌]]和植物根的影响,它们改善了气体循环,珊瑚礁中碳酸钙以固体形式沉积在海底。碳酸钙被生物用来制造含碳测试和贝壳。一旦死亡,这些生物的壳就会落到海底,在那里它们会产生白垩和石灰岩的沉积物。 <br />
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One of these organisms is ''[[Emiliania huxleyi]]'', an abundant [[coccolithophore]] [[algae]] which also has a role in the formation of [[cloud]]s.<ref name="Harding2006">{{cite book |author=Harding, Stephan |title=Animate Earth |publisher=Chelsea Green Publishing |date=2006 |pages=65 |isbn=978-1-933392-29-5 }}</ref> CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants.{{citation needed|date=July 2015}} Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean [[algal bloom]]s are also increasing.<ref>{{Cite web | date = 12 September 2007 | title = Interagency Report Says Harmful Algal Blooms Increasing | url = http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | url-status = dead | archiveurl = https://web.archive.org/web/20080209234239/http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | archivedate = 9 February 2008 }}</ref><br />
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In 1988, climatologist Stephen Schneider organised a conference of the American Geophysical Union. The first Chapman Conference on Gaia,<br />
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在1988年,气候学家史蒂芬·史奈德组织了一次美国美国地球物理联盟协会的会议。关于盖亚假说的第一次查普曼会议,<br />
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[[Lichen]] and other organisms accelerate the [[weathering]] of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the Daisyworld Model (and its modifications, above) as evidence against most of these criticisms.<br />
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然而,洛夫洛克和其他支持盖亚理论的科学家确实试图反驳这样一种说法,即这种假设不科学,因为不可能通过控制实验来检验它。例如,针对盖亚假说是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修正,上文)作为反驳大多数这些批评的证据。<br />
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==History历史==<br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of teleologism ceased, following this conference.<br />
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洛夫洛克谨慎地提出了盖亚假说的一个版本,该假说没有声称盖亚假说有意或有意地在她的环境中维持生命赖以生存的复杂平衡。看起来,盖亚假说“故意”行为的说法只是他那本广受欢迎的书中的一个比喻性陈述,并不是字面意义上的理解。这种对盖亚假说的新陈述更能为科学界所接受。在这次会议之后,大多数关于目的论的指责都停止了。<br />
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===Precedents先例===<br />
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[[File:NASA-Apollo8-Dec24-Earthrise.jpg|thumb|''[[Earthrise]]'' taken from [[Apollo 8]] on December 24, 1968]]<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000, the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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到2000年6月23日在西班牙巴伦西亚举行关于盖亚假说的第二次查普曼会议时,情况发生了重大变化。与其讨论盖亚假说的目的论观点,或盖亚假说的“类型” ,不如将重点放在具体的机制上,通过这些机制,基本的短期内稳态在一个重要的进化的长期结构变化的框架内得以维持。<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The [[Gaia (mythology)|mythical Gaia]] was the primal Greek goddess personifying the [[Earth]], the Greek version of "[[Mother Nature]]" (from Ge = Earth, and Aia = <br />
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[[PIE]] grandmother), or the [[Earth Mother]]. James Lovelock gave this name to his hypothesis after a suggestion from the novelist [[William Golding]], who was living in the same village as Lovelock at the time ([[Bowerchalke]], [[Wiltshire]], UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry.<ref name=vanish09 /> Golding later made reference to Gaia in his [[Nobel prize]] acceptance speech.<br />
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The major questions were:<br />
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主要的问题是:<br />
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In the eighteenth century, as [[geology]] consolidated as a modern science, [[James Hutton]] maintained that geological and biological processes are interlinked.<ref name=CapraWeb>{{cite book |author=Capra, Fritjof |title=The web of life: a new scientific understanding of living systems |publisher=Anchor Books |location=Garden City, N.Y |date=1996 |page=[https://archive.org/details/weboflifenewscie00capr/page/23 23] |isbn=978-0-385-47675-1 |url=https://archive.org/details/weboflifenewscie00capr/page/23 }}</ref> Later, the [[naturalist]] and explorer [[Alexander von Humboldt]] recognized the coevolution of living organisms, climate, and Earth's crust.<ref name=CapraWeb /> In the twentieth century, [[Vladimir Vernadsky]] formulated a theory of Earth's development that is now one of the foundations of ecology. Vernadsky was a Ukrainian [[geochemist]] and was one of the first scientists to recognize that the oxygen, nitrogen, and carbon dioxide in the Earth's atmosphere result from biological processes. During the 1920s he published works arguing that living organisms could reshape the planet as surely as any physical force. Vernadsky was a pioneer of the scientific bases for the environmental sciences.<ref>S.R. Weart, 2003, ''The Discovery of Global Warming'', Cambridge, Harvard Press</ref> His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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"How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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“被称为盖亚的全球生物地球化学/气候系统是如何及时发生变化的?它的历史是什么?盖亚假说能够在一个时间尺度上保持系统的稳定性,但是在更长的时间尺度上仍然经历矢量变化吗?如何利用地质记录来检验这些问题? ”<br />
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"What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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“盖亚假说的结构是什么?这些反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由在任何特定时间进行的学科研究务实地决定的,还是有一些部分应该被认为是最真实的,以了解盖亚假说随着时间的推移包含进化中的生物体?盖亚系统这些不同部分之间的反馈是什么? 对盖亚假说作为全球生态系统的结构和生命的生产力来说,物质的近乎封闭意味着什么? ”<br />
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Also in the turn to the 20th century [[Aldo Leopold]], pioneer in the development of modern [[environmental ethics]] and in the movement for [[wilderness]] conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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"How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
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“盖亚假说过程和现象的模型如何与现实相关,它们如何帮助解决和理解盖亚?雏菊世界的成果如何转移到现实世界?什么是“雏菊”的主要候选人?我们发现雏菊与否对盖亚理论重要吗?我们应该怎样寻找雏菊,我们应该加紧寻找吗?如何利用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖亚机制? ”<br />
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{{quotation|It is at least not impossible to regard the earth's parts—soil, mountains, rivers, atmosphere etc,—as organs or parts of organs of a coordinated whole, each part with its definite function. And if we could see this whole, as a whole, through a great period of time, we might perceive not only organs with coordinated functions, but possibly also that process of consumption as replacement which in biology we call metabolism, or growth. In such case we would have all the visible attributes of a living thing, which we do not realize to be such because it is too big, and its life processes too slow.| Stephan Harding | ''Animate Earth''.<ref>Harding, Stephan. ''Animate Earth Science, Intuition and Gaia''. Chelsea Green Publishing, 2006, p. 44. {{ISBN|1-933392-29-0}}</ref>}}<br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise entropy production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
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1997年,泰勒·沃尔克认为,盖亚系统几乎不可避免地会产生,这是一种向远离平衡的稳态演化的结果,这种平衡状态使熵产生最大化,克莱顿(2004)同意这样的说法:“自稳态行为可以从与行星反照率相关的MEP状态中产生”;“……一个如盖亚假说所述,处于MEP状态的生物地球很可能导致地球系统在长时间尺度上的近稳态行为。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。<br />
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Another influence for the Gaia hypothesis and the [[environmental movement]] in general came as a side effect of the [[Space Race]] between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph ''[[Earthrise]]'' taken by astronaut [[William Anders]] in 1968 during the [[Apollo 8]] mission became, through the [[Overview Effect]] an early symbol for the global ecology movement.<ref>[http://digitaljournalist.org/issue0309/lm11.html 100 Photographs that Changed the World by Life - The Digital Journalist]</ref><br />
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盖亚假说和[[环境运动]]的另一个总体影响来自苏联和美利坚合众国之间[[太空竞赛]]的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球的整体面貌。1968年宇航员[[William Anders]]在[[Apollo 8]]任务期间拍摄的照片“[[地球升起]”,通过[[概述效果]]成为全球生态运动的早期标志<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<br />
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第四次关于盖亚假说的国际会议,由北弗吉尼亚地区公园管理局和其他机构主办,于2006年10月在弗吉尼亚州乔治梅森大学的阿灵顿校区举行。<br />
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===Formulation of the hypothesis假说形成===<br />
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[[File:James Lovelock in 2005.jpg|thumb|[[James Lovelock]], 2005]]<br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
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马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。Lynn Margulis是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the [[Jet Propulsion Laboratory]] in California on methods of detecting [[life on Mars (planet)|life on Mars]].<ref name="Lovelock1965">{{cite journal | author = Lovelock, J.E. | date = 1965 | title = A physical basis for life detection experiments | journal = [[Nature (journal)|Nature]] | volume = 207 | issue = 7 | pages = 568–570 | doi = 10.1038/207568a0 | pmid=5883628|bibcode = 1965Natur.207..568L | ref = harv}}</ref><ref>{{Cite web |url=http://www.jameslovelock.org/page4.html |title=Geophysiology |access-date=2007-05-05 |archive-url=https://web.archive.org/web/20070506073502/http://www.jameslovelock.org/page4.html |archive-date=2007-05-06 |url-status=dead }}</ref> The first paper to mention it was ''Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life'', co-authored with C.E. Giffin.<ref>{{cite journal | author1 = Lovelock, J.E. | author2 = Giffin, C.E. | date = 1969 | title = Planetary Atmospheres: Compositional and other changes associated with the presence of Life | journal = Advances in the Astronautical Sciences | volume = 25 | pages = 179–193 | isbn = 978-0-87703-028-7 | ref = harv}}</ref> A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the [[Pic du Midi de Bigorre|Pic du Midi observatory]], planets like Mars or Venus had atmospheres in [[chemical equilibrium]]. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
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这次会议将盖亚假说作为一种科学和隐喻的手段,来理解我们如何开始解决21世纪的问题,如气候变化和持续的环境破坏。<br />
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Lovelock formulated the ''Gaia Hypothesis'' in journal articles in 1972<ref name="J1972">{{cite journal | author = J. E. Lovelock | title = Gaia as seen through the atmosphere | date = 1972 | journal = [[Atmospheric Environment]] | volume = 6 | issue = 8 | pages = 579–580 | doi = 10.1016/0004-6981(72)90076-5 | ref = harv|bibcode = 1972AtmEn...6..579L }}</ref> and 1974,<ref name="lovelock1974" /> followed by a popularizing 1979 book ''Gaia: A new look at life on Earth''. An article in the ''[[New Scientist]]'' of February 6, 1975,<ref>Lovelock, John and Sidney Epton, (February 8, 1975). "The quest for Gaia". [https://books.google.com/books?id=pnV6UYEkU4YC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false New Scientist], p. 304.</ref> and a popular book length version of the hypothesis, published in 1979 as ''The Quest for Gaia'', began to attract scientific and critical attention.<br />
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Lovelock called it first the Earth feedback hypothesis,<ref name="Lovelock01">{{harvnb|Lovelock, James|2001}}</ref> and it was a way to explain the fact that combinations of chemicals including [[oxygen]] and [[methane]] persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as Ford Doolittle, Richard Dawkins and Stephen Jay Gould. Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists, He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as autopoietic or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole. With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<br />
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在最初几乎没有引起科学家的注意之后(从1969年到1977年) ,有一段时间,最初的盖亚假说受到了一些科学家的批评,如福特杜利特,理查德道金斯和史蒂芬·古尔德。洛夫洛克说,因为他的假说是以一位希腊女神的名字命名的,并得到许多非科学家的拥护,他想知道实现自我调节体内平衡的实际机制。在为盖亚辩护时,戴维•阿布拉姆认为,古尔德忽视了一个事实,即“机制”本身就是一个隐喻——尽管这个隐喻极其常见,而且往往不为人所知——这个隐喻让我们把自然和生命系统看作是由外部组织和建造的机器(而不是自动生成或自组织现象)。根据阿布拉姆的说法,机械隐喻使我们忽略了生命实体的活跃性或代表性,而盖亚假说的有机隐喻强调了生物群和整个生物圈的活跃性。关于盖亚的因果关系,洛夫洛克认为没有单一的机制是负责任的,各种已知机制之间的联系可能永远不会被人知道,这在生物学和生态学的其他领域是理所当然地被接受的,并且由于其他原因,特定的敌意是保留给他自己的假设的。<br />
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[[File:Lynn Margulis.jpg|thumb|left|[[Lynn Margulis]]]]<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of greedy reductionism in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<br />
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除了澄清他的语言和理解什么是生命形式,洛夫洛克自己把大部分的批评归因于他的批评者缺乏对非线性数学的理解,以及贪婪还原主义的线性化形式,在这种形式中,所有事件都必须立即归因于事件发生之前的特定原因。他还表示,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,以及一些自我调节现象可能无法在数学上解释。<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<ref>{{cite journal | first1=W.D. | last1=Hamilton | first2=T.M. | last2=Lenton | title=Spora and Gaia: how microbes fly with their clouds | journal=Ethology Ecology & Evolution | volume=10 | pages=1–16 | date=1998 | issue=1 | url=http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | format=PDF | doi=10.1080/08927014.1998.9522867 | ref=harv | url-status=dead | archiveurl=https://web.archive.org/web/20110723055017/http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | archivedate=2011-07-23 }}</ref><br />
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Evolutionary biologist W. D. Hamilton called the concept of Gaia Copernican, adding that it would take another Newton to explain how Gaian self-regulation takes place through Darwinian natural selection. More recently Ford Doolittle building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis. <br />
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进化生物学家W.D.Hamilton称盖亚假说为哥白尼式的概念,并补充说,需要另一个牛顿来解释盖亚的自我调节是如何通过达尔文的自然选择发生的。最近,Ford Doolittle在他和Inkpen的ITSNTS(这是歌手而不是歌曲)的建议中提出,差异持续性可以在自然选择进化中起到与差异生殖相似的作用,从而为自然选择理论和盖亚假说之间提供了一种可能的调和。 <br />
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In 1971 [[microbiologist]] Dr. [[Lynn Margulis]] joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet.<ref name="Turney, Jon 2003">{{cite book |author=Turney, Jon |title=Lovelock and Gaia: Signs of Life |publisher=Icon Books |location=UK |date=2003 |isbn=978-1-84046-458-0 |url-access=registration |url=https://archive.org/details/lovelockgaiasign0000turn }}</ref> The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of [[eukaryote|eukaryotic]] [[organelle]]s and her contributions to the [[endosymbiotic theory]], nowadays accepted. Margulis dedicated the last of eight chapters in her book, ''The Symbiotic Planet'', to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal Climatic Change in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it. to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background" The CLAW hypothesis, In 2009 the Medea hypothesis was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<br />
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盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论据是,生命对环境产生了有害或不稳定的影响,而不是采取行动加以调节。为了“令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚假说牢牢地放在背景下。”爪假说,2009年提出的美狄亚假说:生命对行星条件有高度有害的(生物杀灭)影响,与盖亚假说直接相反。 <br />
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James Lovelock called his first proposal the ''Gaia hypothesis'' but has also used the term ''Gaia theory''. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments<ref name="J1990">{{cite journal | author = J. E. Lovelock | title = Hands up for the Gaia hypothesis | date = 1990 | journal = [[Nature (journal)|Nature]] | volume = 344 | issue = 6262 | pages = 100–2 | doi = 10.1038/344100a0|bibcode = 1990Natur.344..100L | ref = harv}}</ref> and provided a number of useful predictions.<ref name="Volk2003">{{cite book |author=Volk, Tyler |title=Gaia's Body: Toward a Physiology of Earth |publisher=[[MIT Press]] |location=Cambridge, Massachusetts |date=2003 |isbn=978-0-262-72042-7 }}</ref> In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating.<ref name="vanishing255"/><br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it". Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works". This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<br />
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2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚假说是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚假说的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新想法,并倡导一种整体的方法来研究地球”。在其他地方,他提出了自己的结论:“盖亚假说并不是我们这个世界如何运转的精确图像”。这种说法需要被理解为是指盖亚假说的“强”和“中”形式,生物群遵循的原则是使地球成为最佳(强度5)或有利于生命(强度4),或是作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚假说的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚假说的两种较弱的形式:共同进化的盖亚假说和有影响力的盖亚假说,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚假说”一词是没有用的,两种形式已经被自然选择和适应过程所接受和解释。<br />
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===First Gaia conference第一次盖亚会议===<br />
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In 1985, the first public symposium on the Gaia hypothesis, ''Is The Earth A Living Organism?'' was held at [[University of Massachusetts Amherst]], August 1–6.<ref>{{cite news |last=Joseph |first=Lawrence E. |title=Britain's Whole Earth Guru |work=The New York Times Magazine |date=November 23, 1986 |url=https://www.nytimes.com/1986/11/23/magazine/britain-s-whole-earth-guru.html |accessdate=1 December 2013}}</ref> The principal sponsor was the [[National Audubon Society]]. Speakers included James Lovelock, [[George Wald]], [[Mary Catherine Bateson]], [[Lewis Thomas]], [[John Todd (Canadian biologist)|John Todd]], Donald Michael, [[Christopher Bird]], [[Thomas Berry]], [[David Abram]], [[Michael A. Cohen|Michael Cohen]], and William Fields. Some 500 people attended.<ref>Bunyard, Peter (1996), "Gaia in Action: Science of the Living Earth" (Floris Books)</ref><br />
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1985年,关于盖亚假说的第一次公开研讨会,“地球是一个活的有机体吗?”在马萨诸塞大学阿默斯特举行 <br />
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===Second Gaia conference第二次盖亚会议===<br />
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In 1988, [[climatology|climatologist]] [[Stephen Schneider]] organised a conference of the [[American Geophysical Union]]. The first Chapman Conference on Gaia,<ref name="ReferenceB"/> was held in San Diego, California on March 7, 1988.<br />
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1988年,climatology和Stephen Schneider组织了一次美国地球物理联合会会议。关于盖亚假说的第一次查普曼会议 <br />
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During the "philosophical foundations" session of the conference, [[David Abram]] spoke on the influence of metaphor in science, and of the Gaia hypothesis as offering a new and potentially game-changing metaphorics, while [[James Kirchner]] criticised the Gaia hypothesis for its imprecision. Kirchner claimed that Lovelock and Margulis had not presented one Gaia hypothesis, but four -<br />
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在会议的“哲学基础”会议上,David Abram谈到了隐喻在科学中的影响,盖亚假说提供了一种新的、可能改变游戏规则的隐喻,而James Kirchner则批评盖亚假说的不精确性。基什纳声称,洛夫洛克和马古利斯提出的盖亚假说不是一个,而是四个- <br />
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* [[Coevolution|CoEvolutionary]] Gaia: that life and the environment had evolved in a coupled way. Kirchner claimed that this was already accepted scientifically and was not new.<br />
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* [[Homeostatic]] Gaia: that life maintained the stability of the natural environment, and that this stability enabled life to continue to exist.<br />
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* [[Geophysics|Geophysical]] Gaia: that the Gaia hypothesis generated interest in geophysical cycles and therefore led to interesting new research in terrestrial geophysical dynamics.<br />
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* Optimising Gaia: that Gaia shaped the planet in a way that made it an optimal environment for life as a whole. Kirchner claimed that this was not testable and therefore was not scientific.<br />
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盖亚:生命和环境是以耦合的方式进化的。基什内尔声称,这已经被科学界接受,并不是什么新鲜事。 <br />
盖亚:生命维持着自然环境的稳定,这种稳定性使生命得以继续存在。 <br />
盖亚:盖亚假说引起了人们对地球物理周期的兴趣,因此导致了地球物理动力学中有趣的新研究。 <br />
优化盖亚:盖亚塑造了地球,使之成为整个生命的最佳环境。基什内尔声称,这是不可测试的,因此是不科学的。 <br />
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Of Homeostatic Gaia, Kirchner recognised two alternatives. "Weak Gaia" asserted that life tends to make the environment stable for the flourishing of all life. "Strong Gaia" according to Kirchner, asserted that life tends to make the environment stable, ''to enable'' the flourishing of all life. Strong Gaia, Kirchner claimed, was untestable and therefore not scientific.<ref>{{cite journal | bibcode=1989RvGeo..27..223K | doi = 10.1029/RG027i002p00223 | title=The Gaia hypothesis: Can it be tested? | date=1989 | last1=Kirchner | first1=James W. | journal=Reviews of Geophysics | volume=27 | issue=2 | pages=223 | ref=harv}}</ref><br />
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基什内尔发现了两种选择“软弱的盖亚”断言,为了所有生命的繁衍,生命往往会使环境变得稳定根据基什内尔的说法,“强大的盖亚”断言,生命趋向于使环境稳定,“使”所有生命繁荣昌盛。基什内尔声称,强大的盖亚是不稳定的,因此不科学。 <br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the [[Daisyworld]] Model (and its modifications, above) as evidence against most of these criticisms.<ref name="daisyworld"/> Lovelock said that the Daisyworld model "demonstrates that self-regulation of the global environment can emerge from competition amongst types of life altering their local environment in different ways".<ref>{{cite journal | pmid=10968941 | date=2000 | last1=Lenton | first1=TM | last2=Lovelock | first2=JE | s2cid=5486128 | title=Daisyworld is Darwinian: Constraints on adaptation are important for planetary self-regulation | volume=206 | issue=1 | pages=109–14 | doi=10.1006/jtbi.2000.2105 | journal=Journal of Theoretical Biology | ref=harv}}</ref><br />
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然而,洛夫洛克和其他支持盖亚假说的科学家,确实试图反驳这种说法,即这个假设是不科学的,因为不可能通过受控实验来检验它。例如,针对盖亚假说是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修改,洛夫洛克说,雏菊世界模型“证明了全球环境的自我调节可以通过不同方式改变当地环境的生活类型之间的竞争产生”。 <br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of [[teleology|teleologism]] ceased, following this conference.<br />
洛夫洛克谨慎地提出了盖亚假说的一个版本,没有声称盖亚有意或有意识地维持着生命生存所需的复杂平衡。看来盖亚假说“故意”的行为是他最受欢迎的第一本书中的隐喻性陈述,并不是字面意思。盖亚假说的这一新说法更为科学界所接受。在这次会议之后,[[目的论|目的论]]的大多数指控都停止了。<br />
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===Third Gaia conference第三次盖亚会议===<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000,<ref>{{cite news|last=Simón|first=Federico|title=GEOLOGÍA Enfoque multidisciplinar La hipótesis Gaia madura en Valencia con los últimos avances científicos|journal=El País|date=21 June 2000|url=http://elpais.com/diario/2000/06/21/futuro/961538404_850215.html|accessdate=1 December 2013|language=spanish}}</ref> the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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The major questions were:<ref>{{cite web|title=General Information Chapman Conference on the Gaia Hypothesis University of Valencia Valencia, Spain June 19-23, 2000 (Monday through Friday) |url=http://www.agu.org/meetings/chapman/chapman_archive/cc00bcall.html |work=AGU Meetings |accessdate=7 January 2017 |author=American Geophysical Union }}</ref><br />
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# "How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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# "What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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# "How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
“被称为盖亚的全球生物地球化学/气候系统是如何随时间变化的?它的历史是什么?盖亚能在一个时间尺度上保持系统的稳定性,但在较长的时间尺度上仍能经历向量变化吗?如何利用地质记录来检验这些问题?” <br />
“盖亚假说的结构是什么?反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由任何给定时间正在进行的任何学科研究实际确定的,还是有一组应该被视为最真实的部分来理解盖亚假说,即随着时间的推移包含进化中的有机体?盖亚系统的这些不同部分之间的反馈是什么?物质的接近封闭对盖亚作为全球生态系统的结构和生命的生产力意味着什么?” <br />
“盖亚假说过程和现象的模型如何与现实联系起来,它们如何帮助解决和理解盖亚假说?雏菊世界的结果如何传递到真实世界?“雏菊”的主要候选对象是什么?我们是否找到雏菊对盖亚理论有意义吗?我们应该如何寻找雏菊,我们应该加强搜索?如何使用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖亚机制?” <br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise [[entropy]] production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
1997年,泰勒·沃尔克认为,盖亚系统几乎不可避免地会产生,这是朝着使熵产量最大化的远非平衡平衡平衡状态演化的结果,克莱顿(2004)同意这样的说法:“自稳行为可以从与行星反照率相关的MEP状态中产生”;“……生物地球在MEP状态下的行为很可能导致地球系统在长时间尺度上的近稳态行为,正如盖亚假说所述”。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。 <br />
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===Fourth Gaia conference第四次盖亚会议===<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<ref>{{cite web|title=Gaia Theory Conference at George Mason University Law School|url=http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|accessdate=1 December 2013|author=Official Site of Arlington County Virginia|archive-url=https://web.archive.org/web/20131203043657/http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|archive-date=2013-12-03|url-status=dead}}</ref><br />
第四届盖亚假说国际会议于2006年10月在乔治梅森大学阿灵顿分校举行,会议由北弗吉尼亚州公园管理局和其他机构赞助。 <br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。林恩 马古拉斯是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
这次会议将盖亚假说作为一种科学和隐喻来探讨,以此来理解我们如何着手解决21世纪的问题,如气候变化和持续的环境破坏<br />
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==Criticism批评==<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as [[Ford Doolittle]],<ref name=":1">{{Cite journal|last=Doolittle|first=W. F.|year=1981|title=Is Nature Really Motherly|url=|journal=The Coevolution Quarterly|volume=Spring|pages=58–63|via=}}</ref> [[Richard Dawkins]]<ref name=":2">{{Cite book|title=The Extended Phenotype: the Long Reach of the Gene|last=Dawkins|first=Richard|publisher=Oxford University Press|year=1982|isbn=978-0-19-286088-0|location=|pages=}}</ref> and [[Stephen Jay Gould]].<ref name="ReferenceB">Turney, Jon. "Lovelock and Gaia: Signs of Life" (Revolutions in Science)</ref> Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists,<ref name="Lovelock01"/> the Gaia hypothesis was interpreted as a [[neo-Pagan]] [[religion]]. Many scientists in particular also criticised the approach taken in his popular book ''Gaia, a New Look at Life on Earth'' for being [[teleology|teleological]]—a belief that things are purposeful and aimed towards a goal. Responding to this critique in 1990, Lovelock stated, "Nowhere in our writings do we express the idea that planetary self-regulation is purposeful, or involves foresight or planning by the [[biota (ecology)|biota]]".<br />
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最初很少受到科学家的关注(从1969年到1977年),此后的一段时间里,最初的盖亚假说受到了许多科学家的批评,比如福特·杜利特,理查德·道金斯和斯蒂芬·杰伊·古尔德洛夫洛克曾说过,因为他的假设是以希腊女神的名字命名的,新盖亚假说被许多非教派的科学家解释为。特别是许多科学家还批评了他的畅销书《盖亚》中采用的方法,认为地球上的生命是目的论的,认为事物是有目的的,是有目的的。洛夫洛克在1990年回应这一批评时说:“在我们的著作中我们没有任何地方表达行星自我调节是有目的的,或涉及生物群的远见或计划。”<br />
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[[Stephen Jay Gould]] criticised Gaia as being "a metaphor, not a mechanism."<ref name="Gould 1997">{{cite journal |author=Gould S.J. |title=Kropotkin was no crackpot |journal=Natural History |volume=106 |pages=12–21 |date=June 1997 |url=http://libcom.org/library/kropotkin-was-no-crackpot |ref=harv}}</ref> He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as [[autopoiesis|autopoietic]] or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole.<ref>Abram, D. (1988) "The Mechanical and the Organic: On the Impact of Metaphor in Science" in Scientists on Gaia, edited by Stephen Schneider and Penelope Boston, Cambridge, Massachusetts: MIT Press, 1991</ref><ref>{{cite web|url=http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |title=The Mechanical and the Organic |accessdate=August 27, 2012 |url-status=dead |archiveurl=https://web.archive.org/web/20120223165936/http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |archivedate=February 23, 2012 }}</ref> With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<ref name="Lovelock, James 2001">Lovelock, James (2001), ''Homage to Gaia: The Life of an Independent Scientist'' (Oxford University Press)</ref><br />
史蒂芬·杰伊·古尔德批评盖亚假说是“一种隐喻,而不是一种机制。”他想知道实现自我调节内稳态的实际机制。在为盖亚假说辩护时,大卫·艾布拉姆认为古尔德忽略了一个事实,即“机制”本身就是一个隐喻——尽管这是一个非常常见且常常未被人认识的隐喻——它使我们把自然和生命系统看作是从外部组织和建造的机器(而不是自动或自组织的)现象)。艾布拉姆认为,机械隐喻使我们忽视了生命实体的活动性或能动性,而盖亚假说的有机体隐喻强调了生物群和生物圈作为一个整体的能动性。关于盖亚假说的因果关系,洛夫洛克认为没有单一的机制负责各种已知机制之间的联系可能永远不为人所知,这一点在其他生物学和生态学领域都是理所当然的,而具体的敌意是出于其他原因留给他自己的假设的<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of [[greedy reductionism]] in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<ref name="Lovelock, James 2001"/><br />
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除了澄清自己的语言和对生命形式的理解之外,洛夫洛克自己将大部分批评归咎于批评家对非线性数学的缺乏理解,以及贪婪还原论的线性化形式,在这种形式中,所有事件都必须在事实发生之前立即归因于特定的原因。他还指出,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,有些自我调节的现象可能无法用数学解释 <br />
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===Natural selection and evolution自然选择和进化===<br />
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Lovelock has suggested that global biological feedback mechanisms could evolve by [[natural selection]], stating that organisms that improve their environment for their survival do better than those that damage their environment. However, in the early 1980s, [[Ford Doolittle|W. Ford Doolittle]] and [[Richard Dawkins]] separately argued against this aspect of Gaia. Doolittle argued that nothing in the [[genome]] of individual organisms could provide the feedback mechanisms proposed by Lovelock, and therefore the Gaia hypothesis proposed no plausible mechanism and was unscientific.<ref name=":1" /> Dawkins meanwhile stated that for organisms to act in concert would require foresight and planning, which is contrary to the current scientific understanding of evolution.<ref name=":2" /> Like Doolittle, he also rejected the possibility that feedback loops could stabilize the system.<br />
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洛夫洛克提出,全球生物反馈机制可以通过自然选择而进化,他指出,为生存而改善环境的生物比那些破坏环境的生物做得更好。然而,在20世纪80年代早期,W·福特·杜立德和理查德·道金斯分别反对盖亚假说的这一方面。杜立德认为,单个生物体的基因组中没有任何东西能够提供洛夫洛克提出的反馈机制,因此盖亚假说没有提出任何合理的机制,是不科学的。道金斯同时指出,要使有机体协同行动,就需要有远见和计划,这与当前科学界对进化论的理解相悖和杜立德一样,他也拒绝了反馈回路可以稳定系统的可能性。<br />
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[[Lynn Margulis]], a microbiologist who collaborated with Lovelock in supporting the Gaia hypothesis, argued in 1999, that "[[Charles Darwin|Darwin]]'s grand vision was not wrong, only incomplete. In accentuating the direct competition between individuals for resources as the primary selection mechanism, Darwin (and especially his followers) created the impression that the environment was simply a static arena". She wrote that the composition of the Earth's atmosphere, hydrosphere, and lithosphere are regulated around "set points" as in [[homeostasis]], but those set points change with time.<ref name="ReferenceA">Margulis, Lynn. Symbiotic Planet: A New Look At Evolution. Houston: Basic Book 1999</ref><br />
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Lynn Margulis,一位与Lovelock合作支持盖亚假说的微生物学家,在1999年指出,“达尔文的宏伟愿景没有错,只是不完整。达尔文(特别是他的追随者)强调个人之间对资源的直接竞争是主要的选择机制,他给人的印象是环境只是一个静态的竞技场”。她写道,地球大气、水圈和岩石圈的组成都是围绕着“设定点”来调节的,就像在体内平衡中一样,但是这些设定点会随着时间的推移而变化 <br />
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Evolutionary biologist [[W. D. Hamilton]] called the concept of Gaia [[Nicolaus Copernicus|Copernican]], adding that it would take another [[Isaac Newton|Newton]] to explain how Gaian self-regulation takes place through Darwinian [[natural selection]].<ref name=vanish09>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, pp. 195-197. {{ISBN|978-0-465-01549-8}}</ref>{{better source|date=September 2012|reason=it should be possible to find the original place where Hamilton said this}} More recently [[Ford Doolittle]] building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal<ref name="ITSNTS">Doolittle WF, Inkpen SA. Processes and patterns of interaction as units of selection: An introduction to ITSNTS thinking. [https://www.pnas.org/content/115/16/4006 PNAS April 17, 2018 115 (16)] 4006-4014 </ref> proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis<ref name="Darwinizing Gaia">Doolittle WF. Darwinizing Gaia. [https://doi.org/10.1016/j.jtbi.2017.02.015 Journal of Theoretical BiologyVolume 434], 7 December 2017, Pages 11-19 </ref>. <br />
进化生物学家汉密尔顿称盖亚哥白尼为盖亚的概念,他补充说,需要另一个牛顿来解释盖亚的自我调节是如何通过达尔文的自然选择发生的。通过自然选择在进化过程中的繁殖,从而为自然选择理论和盖亚假说提供了可能的调和。 <br />
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===Criticism in the 21st century21世纪的批评===<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal ''Climatic Change'' in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it.<ref name="kirchner2002"/><ref name="volk2002"/> Several recent books have criticised the Gaia hypothesis, expressing views ranging from "... the Gaia hypothesis lacks unambiguous observational support and has significant theoretical difficulties"<ref>{{cite book |last=Waltham |first=David |authorlink=David Waltham |date=2014 |title=Lucky Planet: Why Earth is Exceptional – and What that Means for Life in the Universe |url=https://archive.org/details/luckyplanetwhyea0000walt |location= |publisher=Icon Books |page= |isbn=9781848316560 |accessdate= |url-access=registration }}</ref> to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background"<ref name="beerling2007"/> to "The Gaia hypothesis is supported neither by evolutionary theory nor by the empirical evidence of the geological record".<ref>{{cite book |last1=Cockell |first1=Charles |authorlink1=Charles Cockell |last2=Corfield |first2=Richard |last3=Dise |first3= Nancy |last4=Edwards |first4=Neil |last5=Harris |first5=Nigel |date=2008 |title= An Introduction to the Earth-Life System |url= http://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/palaeontology-and-life-history/introduction-earth-life-system |location=Cambridge (UK) |publisher= Cambridge University Press |page= |isbn= 9780521729536 |accessdate= }}</ref> The [[CLAW hypothesis]],<ref name="CLAW87" /> initially suggested as a potential example of direct Gaian feedback, has subsequently been found to be less credible as understanding of [[cloud condensation nuclei]] has improved.<ref>{{Citation |last1= Quinn |first1=P.K. |last2= Bates |first2=T.S. |title =The case against climate regulation via oceanic phytoplankton sulphur emissions |journal =Nature |volume=480 |issue=7375 |pages =51–56 |date = 2011 |doi=10.1038/nature10580|bibcode = 2011Natur.480...51Q |pmid=22129724|url=https://zenodo.org/record/1233319 }}</ref> In 2009 the [[Medea hypothesis]] was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<ref>Peter Ward (2009), ''The Medea Hypothesis: Is Life on Earth Ultimately Self-Destructive?'', {{ISBN|0-691-13075-2}}</ref><br />
盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论点是许多例子,其中生命对环境产生了有害或不稳定的影响,而不是采取行动来调节它。最近几本书批评了盖亚假说,表达了从“盖亚假说缺乏明确的观察支持,并且有重大的理论困难“到”令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在背景中“到”盖亚假说既没有进化论的支持,也没有地质记录的经验证据的支持。爪假说最初被认为是盖安直接反馈的一个潜在例子,后来被发现对云的理解不那么可信凝聚核已经得到了改善2009年,美狄亚假说被提出:生命对行星的状况有非常有害的(杀生的)影响,这与盖亚假说直接相反 <br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it".<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=209 |isbn=9780691121581 |accessdate= }}</ref> Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works".<ref>{{Citation |last= Tyrrell |first = Toby |title =Gaia: the verdict is… |journal = New Scientist |volume = 220 |issue = 2940 |pages = 30–31 |date= 26 October 2013 |doi=10.1016/s0262-4079(13)62532-4}}</ref> This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=208 |isbn=9780691121581 |accessdate= }}</ref><br />
2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚假说是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚假说的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新思想,并倡导一种研究地球的整体方法。”在其他地方,他提出了自己的结论:“盖亚假说并不是一个关于如何进行的精确描述我们的世界在运转。”这种说法需要被理解为是指盖亚假说的“强大”和“温和”形式,生物群遵循的原则是使地球处于最佳状态(强度5)或有利于生命(强度4),或者它作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚假说的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚假说的两种较弱的形式:共同进化德盖亚假说和有影响力的盖亚假说,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚假说”一词是没有用的,两种形式已经被自然选择和适应过程所接受和解释 <br />
Category:Cybernetics<br />
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类别: 控制论<br />
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Category:Ecological theories<br />
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范畴: 生态学理论<br />
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==See also==<br />
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Category:Superorganisms<br />
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类别: 超级有机体<br />
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{{Portal|Environment|Earth sciences|Geography}}<br />
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Category:Climate change feedbacks<br />
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类别: 气候变化反馈<br />
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Category:1965 introductions<br />
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类别: 1965年引言<br />
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* {{annotated link|Biocoenosis}}<br />
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Category:Biogeochemistry<br />
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类别: 生物地球化学<br />
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* {{annotated link|Earth science}}<br />
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Category:Earth<br />
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类别: 地球<br />
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* {{annotated link|Environmentalism}}<br />
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Category:Biological hypotheses<br />
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类别: 生物学假说<br />
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* {{annotated link|Gaianism}}<br />
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Category:Astronomical hypotheses<br />
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* {{annotated link|Holism}}<br />
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Category:Meteorological hypotheses<br />
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类别: 气象假说<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Gaia hypothesis]]. Its edit history can be viewed at [[盖亚假说/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%9B%96%E4%BA%9A%E5%81%87%E8%AF%B4&diff=18463盖亚假说2020-11-16T09:10:36Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Hypothesis that living organisms interact with their surroundings in a self-regulating system}}<br />
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[[File:The Earth seen from Apollo 17.jpg|thumb|The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth]]'s conditions, as the Earth is the only planet currently known to harbour life (''[[The Blue Marble]]'', 1972 [[Apollo 17]] photograph)]]<br />
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The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth's conditions, as the Earth is the only planet currently known to harbour life (The Blue Marble, 1972 Apollo 17 photograph)]]<br />
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行星可居住性的研究部分基于对[[地球条件]的了解推断,因为地球是目前已知的唯一一颗拥有生命的行星 <br />
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The '''Gaia hypothesis''' {{IPAc-en|ˈ|ɡ|aɪ|.|ə}}, also known as the '''Gaia theory''' or the '''Gaia principle''', proposes that living [[organism]]s interact with their [[Inorganic compound|inorganic]] surroundings on [[Earth]] to form a [[Synergy|synergistic]] and [[Homeostasis|self-regulating]], [[complex system]] that helps to maintain and perpetuate the conditions for [[life]] on the planet.<br />
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The Gaia hypothesis , also known as the Gaia theory or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet.<br />
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盖亚假说(又称盖亚理论或盖亚原理)提出,生物体与地球上的无机环境相互作用,形成一个协同和自我调节的复杂系统,有助于维持和延续地球上的生命条件。<br />
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The hypothesis was formulated by the chemist [[James Lovelock]]<ref name="J1972" /> and co-developed by the microbiologist [[Lynn Margulis]] in the 1970s.<ref name="lovelock1974">{{cite journal|last1=Lovelock|first1=J.E.|last2=Margulis|first2=L.|title=Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis|journal=Tellus|date=1974|volume=26|series=Series A|issue=1–2|pages=2–10|doi=10.1111/j.2153-3490.1974.tb01946.x|publisher=International Meteorological Institute|location=Stockholm|issn=1600-0870|ref=harv|bibcode=1974Tell...26....2L}}</ref> Lovelock named the idea after [[Gaia]], the primordial goddess who personified the Earth in [[Greek mythology]]. In 2006, the [[Geological Society of London]] awarded Lovelock the [[Wollaston Medal]] in part for his work on the Gaia hypothesis.<ref>{{cite web|title=Wollaston Award Lovelock|url=https://www.geolsoc.org.uk/About/History/Awards-Citations-Replies-2001-Onwards/2006-Awards-Citations-Replies|accessdate=19 October 2015}}</ref><br />
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The hypothesis was formulated by the chemist James Lovelock Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis.<br />
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这个假设是由化学家詹姆斯 洛夫洛克提出的,他以希腊神话中地球的化身盖亚的名字命名了这个想法。2006年,伦敦地质学会授予洛夫洛克沃拉斯顿勋章,部分原因是他在<font color="#ff8000"> 盖亚假说Gaia hypothesis</font>方面的工作。 <br />
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Topics related to the hypothesis include how the [[biosphere]] and the [[evolution]] of organisms affect the stability of [[global temperature]], [[salinity]] of [[seawater]], [[atmospheric oxygen]] levels, the maintenance of a [[hydrosphere]] of liquid water and other environmental variables that affect the [[habitability of Earth]].<br />
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Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth.<br />
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与该假设有关的主题包括生物圈和生物体的进化如何影响全球温度的稳定性、海水的盐度、大气中的氧含量、液态水的水圈的维持以及其他影响地球宜居性的环境变量。<br />
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The Gaia hypothesis was initially criticized for being [[teleological]] and against the principles of [[natural selection]], but later refinements aligned the Gaia hypothesis with ideas from fields such as [[Earth system science]], [[biogeochemistry]] and [[systems ecology]].<ref name="Turney, Jon 2003"/><ref name="Schwartzman2002">{{cite book |author=Schwartzman, David |title=Life, Temperature, and the Earth: The Self-Organizing Biosphere |publisher=Columbia University Press |date=2002 |isbn=978-0-231-10213-1 }}</ref><ref>Gribbin, John (1990), "Hothouse earth: The greenhouse effect and Gaia" (Weidenfeld & Nicolson)</ref> Lovelock also once described the "geophysiology" of the Earth.<ref name="agesofgaia">Lovelock, James, (1995) "The Ages of Gaia: A Biography of Our Living Earth" (W.W.Norton & Co)</ref>{{Explain|date=December 2017}} Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<ref name="kirchner2002">{{Citation |last= Kirchner |first = James W. |title =Toward a future for Gaia theory |journal=[[Climatic Change (journal)|Climatic Change]] |volume = 52 |issue = 4 |pages = 391–408 |date = 2002 | doi = 10.1023/a:1014237331082 }}</ref><ref name="volk2002">{{Citation |last= Volk |first = Tyler |title =The Gaia hypothesis: fact, theory, and wishful thinking |journal = Climatic Change |volume = 52 |issue = 4 |pages = 423–430 |date = 2002 | doi = 10.1023/a:1014218227825 }}</ref><ref name="beerling2007">{{cite book |last=Beerling |first=David |authorlink=David Beerling|date=2007 |title=The Emerald Planet: How plants changed Earth's history |url=http://ukcatalogue.oup.com/product/9780192806024.do |location=Oxford|publisher=Oxford University Press |page= |isbn= 978-0-19-280602-4 |accessdate= }}</ref><br />
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The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Lovelock also once described the "geophysiology" of the Earth. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<br />
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盖亚假说最初被批评为目的论和反对自然选择的原则,但后来的改进使盖亚假说与来自地球系统科学、生物地球化学和系统生态学等领域的想法相一致。洛夫洛克还曾经描述过地球的“地球物理学”。即便如此,盖亚假说仍然受到批评,今天许多科学家认为它只有微弱的支持,或与现有的证据相矛盾。<br />
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==Overview总览==<br />
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Gaian hypotheses suggest that organisms [[Co-evolution|co-evolve]] with their environment: that is, they "influence their [[abiotic]] environment, and that environment in turn influences the [[Biota (ecology)|biota]] by [[Darwinism|Darwinian process]]". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early [[Bacteria|thermo-acido-philic]] and [[methanogenic bacteria]] towards the oxygen-enriched [[atmosphere]] today that supports more [[Phanerozoic|complex life]].<br />
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Gaian hypotheses suggest that organisms co-evolve with their environment: that is, they "influence their abiotic environment, and that environment in turn influences the biota by Darwinian process". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early thermo-acido-philic and methanogenic bacteria towards the oxygen-enriched atmosphere today that supports more complex life.<br />
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盖恩假说认为,生物体与其环境共同进化:也就是说,它们“影响它们的非生物环境,而环境反过来又通过达尔文的过程影响生物群”。Lovelock(1995)在他的第二本书中提供了证据,展示了从早期嗜酸和产甲烷细菌的世界向今天支持更复杂生命的富氧大气的进化。<br />
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A reduced version of the hypothesis has been called "influential Gaia"<ref name=":02">{{Cite journal|last=Lapenis|first=Andrei G.|year=2002|title=Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?|url=|journal=The Professional Geographer|volume=54 |issue=3|pages=379–391|via=[Peer Reviewed Journal]|doi=10.1111/0033-0124.00337}}</ref> in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the [[Biota (ecology)|biota]] influence certain aspects of the abiotic world, e.g. [[temperature]] and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<ref name=":02" /> and biogeochemical processes. An example is how the activity of [[Photosynthesis|photosynthetic]] bacteria during Precambrian times completely modified the [[Earth's atmosphere|Earth atmosphere]] to turn it aerobic, and thus supports the evolution of life (in particular [[eukaryotic]] life).<br />
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A reduced version of the hypothesis has been called "influential Gaia" in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the biota influence certain aspects of the abiotic world, e.g. temperature and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<br />
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在《生物圈的定向进化: 生物地球化学选择还是盖亚? 》一书中,这一假说的简化版被称为“有影响力的盖亚”由安德烈·G·拉佩尼斯所著,他指出生物群影响着非生物世界的某些方面,例如:温度和大气。这不是一个人的工作,而是一个俄罗斯科学研究的集体,合并成这个同行评议的出版物。它通过“微观力量”阐述了生命与环境的共同进化<br />
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Since barriers existed throughout the twentieth century between Russia and the rest of the world, it is only relatively recently that the early Russian scientists who introduced concepts overlapping the Gaia hypothesis have become better known to the Western scientific community.<ref name=":02" /> These scientists include [[Piotr Kropotkin|Piotr Alekseevich Kropotkin]] (1842–1921) (although he spent much of his professional life outside Russia), Vasil’evich Rizpolozhensky (1847–1918), [[Vladimir Ivanovich Vernadsky]] (1863–1945), and Vladimir Alexandrovich Kostitzin (1886–1963).<br />
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由于二十世纪俄罗斯与世界其他地区之间存在着隔阂,直到最近,引进了盖亚假说重叠概念的早期俄罗斯科学家才为西方科学界所熟知 <br />
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The Gaia hypothesis posits that the Earth is a self-regulating complex system involving the biosphere, the atmosphere, the hydrospheres and the pedosphere, tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<br />
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盖亚假说认为,地球是一个自我调节的复杂系统,包括生物圈、大气层、水圈和土壤圈,作为一个进化的系统紧密结合在一起。这个假说认为,这个被称为盖亚的系统作为一个整体,寻求一个适合当代生命的物理和化学环境。<br />
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Biologists and Earth scientists usually view the factors that stabilize the characteristics of a period as an undirected [[emergent property]] or [[entelechy]] of the system; as each individual species pursues its own self-interest, for example, their combined actiYons may have counterbalancing effects on environmental change. Opponents of this view sometimes reference examples of events that resulted in dramatic change rather than stable equilibrium, such as the conversion of the Earth's atmosphere from a [[reducing environment]] to an [[oxygen]]-rich one at the end of the [[Archean|Archaean]] and the beginning of the [[Proterozoic]] periods.<br />
生物学家和地球科学家通常将稳定一个时期特征的因素视为系统的一个无方向的[[涌现属性]]或[[有目的行为]];例如,由于每个物种都追求自身利益,它们的联合行动可能对环境变化产生抵消作用。反对这一观点的人有时会举出一些事件的例子,这些事件导致了巨大的变化,而不是稳定的平衡,例如在[[太古宙|太古代]]末期和[[元古代]]时期开始时,地球大气从[[还原环境]]转变为富含[[氧气]]。 <br />
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Gaia evolves through a cybernetic feedback system operated unconsciously by the biota, leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially microorganisms, with inorganic elements. These processes establish a global control system that regulates Earth's surface temperature, atmosphere composition and ocean salinity, powered by the global thermodynamic disequilibrium state of the Earth system.<!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
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盖亚通过一个由生物群无意识操作的控制论反馈系统进化,在一个完全的内稳态中达成可居住条件的广泛稳定。地球表面的许多过程对生命的条件至关重要,这些过程依赖于生命形式,特别是微生物与无机元素的相互作用。这些过程建立了一个全球控制系统,由地球系统的全球热力学不平衡状态提供动力,调节地球表面温度、大气成分和海洋盐度。<br />
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Less accepted versions of the hypothesis claim that changes in the biosphere are brought about through the [[Superorganism|coordination of living organisms]] and maintain those conditions through [[homeostasis]]. In some versions of [[Gaia philosophy]], all lifeforms are considered part of one single living planetary being called ''Gaia''. In this view, the atmosphere, the seas and the terrestrial crust would be results of interventions carried out by Gaia through the [[Coevolution|coevolving]] diversity of living organisms.<br />
不太被接受的假说声称生物圈的变化是通过[[超级有机体|生物体的协调]]来实现的,并通过[[内稳态]]来维持这些条件。在一些版本的[[盖亚哲学]]中,所有的生命形式都被认为是一个被称为“盖亚”的生命行星的一部分。在这种观点下,大气、海洋和地壳将是盖亚通过生物多样性进行干预的结果。 <br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of biogeochemistry, and it is being investigated also in other fields like Earth system science. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<br />
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以前在生物地球化学领域已经观察到受生命形式影响的行星内稳态的存在,而且在地球系统科学等其他领域也在研究这一现象。盖亚假说的原创性依赖于这样一种评估: 即使地球或外部事件威胁到这种平衡,这种平衡也是为了保持生命的最佳状态而积极追求的。<br />
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The Gaia hypothesis was an influence on the [[deep ecology]] movement.<ref>David Landis Barnhill, Roger S. Gottlieb (eds.), ''Deep Ecology and World Religions: New Essays on Sacred Ground'', SUNY Press, 2010, p. 32.</ref><br />
盖亚假说对[[深层生态学]]运动产生了影响 <br />
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==Details细节==<br />
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Rob Rohde's palaeotemperature graphs<br />
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罗布·罗德的古温度图<br />
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The Gaia hypothesis posits that the Earth is a self-regulating [[complex system]] involving the [[biosphere]], the [[Earth's atmosphere|atmosphere]], the [[hydrosphere]]s and the [[pedosphere]], tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<ref name="vanishing255">Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 255. {{ISBN|978-0-465-01549-8}}</ref><br />
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盖亚假说假设地球是一个自我调节的[[复杂系统]],包括[[生物圈]]、[[地球大气|大气]]、[[水圈]]和[[土壤圈]],作为一个进化系统紧密耦合。该假说认为,这个系统作为一个整体,称为盖亚,寻求一个最适合当代生活的物理和化学环境 <br />
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Since life started on Earth, the energy provided by the Sun has increased by 25% to 30%; however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on Titan. research has suggested that "oxygen shocks" and reduced methane levels led, during the Huronian, Sturtian and Marinoan/Varanger Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre Phanerozoic biosphere to fully self-regulate.<br />
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自从地球上有生命以来,太阳提供的能量增加了25%到30%;然而,地球表面温度一直保持在适宜居住的水平上,达到了相当规律的高低边缘。洛夫洛克还假设,产甲烷菌在早期大气中产生了较高水平的甲烷,这与在石化烟雾中发现的观点相似,在某些方面与土卫六上的大气相似。研究表明,在休伦期、斯图尔特期和马里诺/瓦朗格冰期,“氧冲击”和甲烷含量降低导致世界几乎变成了一个坚实的“雪球”。这些时代是前显生宙生物圈完全自我调节能力的证据。<br />
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Gaia evolves through a [[Cybernetic#In biology|cybernetic]] [[feedback]] system operated unconsciously by the [[biota (ecology)|biota]], leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially [[microorganisms]], with inorganic elements. These processes establish a global control system that regulates Earth's [[Sea surface temperature|surface temperature]], [[atmosphere composition]] and [[ocean]] [[salinity]], powered by the global thermodynamic disequilibrium state of the Earth system.<ref>Kleidon, Axel. ''How does the earth system generate and maintain thermodynamic disequilibrium and what does it imply for the future of the planet?''. Article submitted to the ''Philosophical Transactions of the Royal Society'' on Thu, 10 Mar 2011</ref><!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
盖亚通过一个[[控制论|生物学|控制论]][[反馈]]系统在[[生物群(生态学)|生物群]]的无意识运作中进化,导致在完全的内稳态中可居住条件的广泛稳定。地球表面对生命条件至关重要的许多过程都依赖于生物,特别是[微生物]与无机元素的相互作用。这些过程建立了一个全球控制系统,调节地球的[[海表温度|表面温度]]、[[大气组成]]和[[海洋]][[盐度]],其动力来自地球系统的全球热力学不平衡状态。<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
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说明了处理温室气体CO2在维持地球温度在可居住范围内起着关键作用。<br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of [[biogeochemistry]], and it is being investigated also in other fields like [[Earth system science]]. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 179. {{ISBN|978-0-465-01549-8}}</ref><br />
受生命形式影响的行星内稳态的存在,以前在[[生物地球化学]]领域就已被观察到,而且在其他领域,如[[地球系统科学]]也在研究中。盖亚假说的独创性依赖于这样一种评估,即积极追求这种体内平衡,以保持生命的最佳状态,即使是在地球或外部事件威胁它们的时候。<br />
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The CLAW hypothesis, inspired by the Gaia hypothesis, proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative feedback loop that acts to stabilise the temperature of the Earth's atmosphere.<br />
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受盖亚假说的启发,CLAW 假说提出了一个在海洋生态系统和地球气候之间运行的反馈回路。该假说特别提出,产生二甲硫醚的浮游植物对气候强迫的变化有反应,这些反应导致了一个负反馈循环,稳定了地球大气的温度。<br />
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===Regulation of global surface temperature地球表面温度的调控===<br />
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[[File:All palaeotemps.png|thumb|480px|Rob Rohde's palaeotemperature graphs]]<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of greenhouse gases may cause negative feedbacks in the environment to become positive feedback. Lovelock has stated that this could bring an extremely accelerated global warming, but he has since stated the effects will likely occur more slowly.<br />
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目前,人口的增加及其活动对环境的影响,例如温室气体的增加,可能导致环境中的负反馈成为正反馈。洛夫洛克表示,这可能会极大地加速全球变暖,但他后来又表示,这种影响可能会发生得更慢。<br />
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{{See also|Paleoclimatology}}<br />
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Since life started on Earth, the energy provided by the [[Sun]] has increased by 25% to 30%;<ref name="Owen1979">{{cite journal | author = Owen, T. | author2 = Cess, R.D. | author3 = Ramanathan, V. | date = 1979 | title = Earth: An enhanced carbon dioxide greenhouse to compensate for reduced solar luminosity | journal = [[Nature (journal)|Nature]] | volume = 277 | pages = 640–2 | doi = 10.1038/277640a0 | issue=5698 | bibcode = 1979Natur.277..640O | ref = harv }}</ref> however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on [[Titan (moon)|Titan]].<ref name="agesofgaia"/> This, he suggests tended to screen out ultraviolet until the formation of the ozone screen, maintaining a degree of homeostasis. However, the [[Snowball Earth]]<ref>Hoffman, P.F. 2001. [http://www.snowballearth.org ''Snowball Earth theory'']</ref> research has suggested that "oxygen shocks" and reduced methane levels led, during the [[Huronian]], [[Sturtian]] and [[Marinoan]]/[[Cryogenian|Varanger]] Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre [[Phanerozoic]] biosphere to fully self-regulate.<br />
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Plots from a standard black and white [[Daisyworld simulation]]<br />
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从一个标准的黑白图[[雏菊世界模拟]]<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
说明了在温室气体维持低于临界温度的过程中,CO2起着至关重要的作用。 <br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic group selection and cooperation between organisms, James Lovelock and Andrew Watson developed a mathematical model, Daisyworld, in which ecological competition underpinned planetary temperature regulation.<br />
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有人批评盖亚假说似乎需要不切实际的群体选择和有机体之间的合作,为了回应这种批评,James Lovelock 和 Andrew Watson建立了一个数学模型---- 雏菊世界,其中生态竞争支撑着地。<br />
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The [[CLAW hypothesis]], inspired by the Gaia hypothesis, proposes a [[feedback|feedback loop]] that operates between [[ocean]] [[ecosystem]]s and the [[Earth]]'s [[climate]].<ref name="CLAW87">{{cite journal |doi=10.1038/326655a0 |author=[[Robert Jay Charlson|Charlson, R. J.]], [[James Lovelock|Lovelock, J. E]], Andreae, M. O. and Warren, S. G. |title=Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate |journal=Nature |volume=326 |issue=6114 |pages=655–661 |date=1987 |bibcode=1987Natur.326..655C |ref=harv }}</ref> The [[hypothesis]] specifically proposes that particular [[phytoplankton]] that produce [[dimethyl sulfide]] are responsive to variations in [[climate forcing]], and that these responses lead to a [[negative feedback|negative feedback loop]] that acts to stabilise the [[temperature]] of the [[Earth's atmosphere]].<br />
受到盖亚假说启发的[[爪假说]]提出了一个在[[海洋]][[生态系统]]和[[地球]]的[[气候]]之间运行的[[反馈|反馈回路]]。<br />
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Daisyworld examines the energy budget of a planet populated by two different types of plants, black daisies and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the albedo of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
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《雏菊世界》调查了一个星球的能量预算,这个星球上生长着两种不同的植物,黑色雏菊和白色雏菊,这两种植物被认为占据了星球表面的很大一部分。雏菊的颜色影响了地球的反照率,黑色的雏菊吸收更多的光线,使地球变暖,而白色的雏菊则反射更多的光线,使地球变冷。人们认为黑色雏菊在较低的温度下生长和繁殖最好,而白色雏菊则被认为在较高的温度下生长最好。当温度上升到接近白色雏菊所喜欢的温度时,白色雏菊伸展出黑色雏菊,导致更大比例的白色表面,更多的阳光被反射,减少热量输入,最终使地球降温。相反,随着气温的下降,黑色雏菊长出了白色雏菊,吸收了更多的阳光,使地球变暖。因此,温度会收敛到与植物繁殖率相等的值。<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of [[greenhouse gases]] may cause [[negative feedback]]s in the environment to become [[positive feedback]]. Lovelock has stated that this could bring an [[James Lovelock#The revenge of Gaia|extremely accelerated global warming]],<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, {{ISBN|978-0-465-01549-8}}</ref> but he has since stated the effects will likely occur more slowly.<ref>Lovelock J., NBC News. [http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite Link] Published 23 April 2012, accessed 22 August 2012. {{Webarchive|url=https://web.archive.org/web/20120913163635/http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite |date=13 September 2012 }}</ref><br />
目前,人口的增加及其活动对环境的影响,如[[温室气体]]的倍增,可能导致环境中的[[负反馈]]变成[[正反馈]]。洛夫洛克曾表示,这可能会带来一场【【James Loveloc【《盖亚的复仇』极度加速的全球变暖】】 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this negative feedback due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
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洛夫洛克和沃森指出,在有限的条件下,如果太阳的能量输出发生变化,由于竞争而产生的负反馈可以将地球温度稳定在支持生命的数值上,而没有生命的地球则会表现出巨大的温度波动。白色和黑色雏菊的百分比会不断变化,以保持植物繁殖率相等的温度值,使两种生命形式都能茁壮成长。<br />
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====Daisyworld simulations雏菊世界模拟====<br />
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[[File:StandardDaisyWorldRun2color.gif|thumb|280px|Plots from a standard black and white [[Daisyworld]] simulation]]<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<br />
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有人认为,这些结果是可以预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的答案。<br />
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{{Main|Daisyworld}}<br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic [[group selection]] and [[Cooperation (evolution)|cooperation]] between organisms, James Lovelock and [[Andrew Watson (scientist)|Andrew Watson]] developed a mathematical model, [[Daisyworld]], in which [[Competition (biology)|ecological competition]] underpinned planetary temperature regulation.<ref name="daisyworld">{{cite journal<br />
有人批评盖亚假说似乎需要有机体之间不切实际的[[群体选择]]和[[合作(进化)|合作]],詹姆斯·洛夫洛克和[[安德鲁·沃森(科学家)|安德鲁·沃森]]开发了一个数学模型,[[雏菊世界]],其中[[竞争(生物学)|生态竞争]]为基础行星温度调节。 <br />
|date = 1983<br />
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Ocean salinity has been constant at about 3.5% for a very long time. Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested that salinity may also be strongly influenced by seawater circulation through hot basaltic rocks, and emerging as hot water vents on mid-ocean ridges. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<br />
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长期以来,海洋盐度一直保持在3.5% 左右。海洋环境中盐度的稳定性很重要,因为大多数细胞需要相当恒定的盐度,一般不能容忍超过5% 的盐度值。恒定的海洋盐度是一个长期存在的秘密,因为没有任何方法可以抵消来自河流的盐的流入。最近有人提出,盐度也可能受到穿过炽热玄武岩的海水循环的强烈影响,并在洋中脊上出现热水喷口。然而,海水的组成离平衡还很远,如果没有有机过程的影响,很难解释这一事实。有一种解释认为,地球历史上盐原的形成是原因之一。据推测,这些是由细菌菌落产生的,它们在生命过程中固定离子和重金属。<br />
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|title = Biological homeostasis of the global environment: the parable of Daisyworld<br />
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|journal = Tellus<br />
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|volume = 35B<br />
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Vostok, Antarctica research station. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
沃斯托克,南极洲研究站。当前期间在左边。<!--基于此图表的GIMP-FX版本的非源材料。现在的版本是正确的,原版的。必须删除这句话:请注意,当前CO2水平超过390ppm,远高于过去40万年来的任何时候-->] <br />
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|pages = 286–9<br />
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|bibcode = 1983TellB..35..284W<br />
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|doi = 10.1111/j.1600-0889.1983.tb00031.x<br />
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The Gaia hypothesis states that the Earth's atmospheric composition is kept at a dynamically steady state by the presence of life. The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than noble gases present in the atmosphere are either made by organisms or processed by them.<br />
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盖亚假说认为,地球的大气组成是由于生命的存在而保持在动态稳定的状态。大气成分提供了现代生活已经适应的条件。大气中除惰性气体以外的所有大气气体,要么是由生物体产生的,要么是由生物体加工的。<br />
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|last1 = Watson | first1= A.J. | last2= Lovelock | first2= J.E<br />
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|issue = 4<br />
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The stability of the atmosphere in Earth is not a consequence of chemical equilibrium. Oxygen is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the Great Oxygenation Event. Since the start of the Cambrian period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume. Traces of methane (at an amount of 100,000 tonnes produced per year) should not exist, as methane is combustible in an oxygen atmosphere.<br />
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地球大气层的稳定性不是化学平衡的结果。氧是一种活性化合物,最终会与地球大气层和地壳中的气体和矿物质结合。在大氧化事件空间站开始之前,大约5000万年左右,氧气才开始在大气中少量地持续存在。自寒武纪以来,大气中氧浓度一直在大气体积的15% 至35% 之间波动。微量的甲烷(每年产生100,000吨)不应该存在,因为甲烷在氧气氛中是可燃的。<br />
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|ref = harv<br />
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}}</ref><br />
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Dry air in the atmosphere of Earth contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases including methane. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. <br />
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地球大气层中的干燥空气大致(按体积计算)含有78.09% 的氮气、20.95% 的氧气、0.93% 的氩气、0.039% 的二氧化碳以及少量的其他气体,包括甲烷。洛夫洛克最初推测,高于25% 的氧气浓度会增加森林大火和森林大火的发生频率。最近在石炭纪和白垩纪煤系地质时期,当O2确实超过了25%时,火成木炭的研究结果支持了 Lovelock 的论点。<br />
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Daisyworld examines the [[Earth's energy budget|energy budget]] of a [[planet]] populated by two different types of plants, black [[Asteraceae|daisies]] and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the [[albedo]] of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
Daisyworld研究了[[地球的能源预算|能源预算]]的[[地球的能源预算]]居住着两种不同类型的植物,黑色的[[菊科的雏菊]]和白色的雏菊,这两种植物被认为占据了地表的很大一部分。雏菊的颜色影响着这个星球的[反照率],因此黑色雏菊吸收更多的光并温暖地球,而白色雏菊则反射更多的光并使地球降温。黑雏菊在较低温度下生长繁殖最好,而白雏菊在较高温度下生长繁殖最好。当温度上升到接近白色雏菊的数值时,白色雏菊的繁殖能力超过了黑色雏菊,导致白色表面的比例增大,更多的阳光被反射,减少了热量输入,最终使地球变冷。相反,随着温度的下降,黑雏菊的繁殖能力超过了白雏菊,吸收了更多的阳光,使地球变暖。因此,温度将收敛到植物繁殖率相等的值。 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this [[negative feedback]] due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
Lovelock和Watson表明,在有限的条件范围内,如果太阳的能量输出发生变化,由于竞争而产生的[[负面反馈]]可以将地球的温度稳定在支持生命的值上,而没有生命的行星则会出现大范围的温度波动。白雏菊和黑雏菊的比例会不断变化,以使温度保持在植物繁殖率相等的值,从而使两种生命形式都能茁壮成长。 <br />
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Gaia scientists see the participation of living organisms in the carbon cycle as one of the complex processes that maintain conditions suitable for life. The only significant natural source of atmospheric carbon dioxide (CO<sub>2</sub>) is volcanic activity, while the only significant removal is through the precipitation of carbonate rocks. Carbon precipitation, solution and fixation are influenced by the bacteria and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
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盖亚的科学家们把生物体参与碳循环看作是维持适合生命条件的复杂过程之一。火山活动是大气中二氧化碳的唯一重要自然来源,而碳酸盐岩的沉淀是大气中二氧化碳唯一重要的去除途径。碳沉淀、溶解和固定受到土壤中细菌和植物根系的影响,这些细菌和植物根系可以改善气体循环,或者在珊瑚礁中,碳酸钙以固体的形式沉积在海底。碳酸钙被活的有机体用来制造含碳的试验和外壳。一旦死亡,生物体的外壳就会沉到海底,在那里它们产生白垩和石灰石的沉淀物。<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<ref>{{cite journal | doi = 10.1023/A:1023494111532 | date = 2003 | last1 = Kirchner | first1 = James W. | journal = Climatic Change | volume = 58 |issue=1–2| pages = 21–45 |title=The Gaia Hypothesis: Conjectures and Refutations | ref = harv}}</ref><br />
有人认为,结果是可预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的反应。 <br />
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One of these organisms is Emiliania huxleyi, an abundant coccolithophore algae which also has a role in the formation of clouds. CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants. Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean algal blooms are also increasing.<br />
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其中一种是赫氏圆石藻,这是一种数量丰富的颗石藻类,也参与了云的形成。CO < sub > 2 </sub > 过量通过增加球石氟化物的寿命来补偿,增加了锁定在海底的 CO < sub > 2 </sub > 的数量。球石粉会增加云量,从而控制地表温度,有助于降低整个地球的温度,有利于地球上植物所必需的降水。近年来,大气中 CO < < sub > 2 </sub > 浓度有所增加,有证据表明,海洋藻华的浓度也在增加。<br />
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===Regulation of oceanic salinity海洋盐度调节 ===<br />
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Lichen and other organisms accelerate the weathering of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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地衣和其他生物加速了岩石表面的风化,而岩石在土壤中的分解也加快了,这要归功于根、真菌、细菌和地下动物的活动。因此,二氧化碳从大气层流向土壤的过程是在生物的帮助下进行调节的。当大气中 CO2水平升高时,温度升高,植物生长。这种生长会增加植物对二氧化碳的消耗,植物会将二氧化碳处理到土壤中,从大气中排出。<br />
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Ocean [[salinity]] has been constant at about 3.5% for a very long time.<ref name=":0">{{Cite book|title=The Introduction to Ocean Sciences|last=Segar|first=Douglas|publisher=Library of Congress|year=2012|isbn=978-0-9857859-0-1|location=http://www.reefimages.com/oceans/SegarOcean3Chap05.pdf|pages=Chapter 5 3rd Edition|quote=|via=}}</ref> Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested<ref name="Gorham19912">{{cite journal|last=Gorham|first=Eville|date=1 January 1991|title=Biogeochemistry: its origins and development|journal=Biogeochemistry|publisher=Kluwer Academic|volume=13|issue=3|pages=199–239|doi=10.1007/BF00002942|issn=1573-515X|ref=harv}}</ref> that salinity may also be strongly influenced by [[seawater]] circulation through hot [[basalt]]ic rocks, and emerging as hot water vents on [[mid-ocean ridge]]s. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<ref name=":0" /><br />
在很长一段时间内,海洋盐度一直保持在3.5%左右。[23]海洋环境中的盐度稳定性非常重要,因为大多数细胞需要相当恒定的盐度,并且通常不能容忍超过5%的盐度值。恒定的海洋盐度是一个长期存在的谜团,因为没有任何过程可以抵消河流中的盐流入。最近有人认为[24]海水通过热玄武质岩石时也会受到海水循环的强烈影响,并在大洋中脊上出现热水喷口。然而,海水的组成远未达到平衡,如果没有有机过程的影响,很难解释这一事实。一个建议的解释是,在整个地球的历史中,盐平原的形成。据推测,这些细菌是由在生命过程中固定离子和重金属的菌落产生的<br />
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In the biogeochemical processes of Earth, sources and sinks are the movement of elements. The composition of salt ions within our oceans and seas is: sodium (Na<sup>+</sup>), chlorine (Cl<sup>−</sup>), sulfate (SO<sub>4</sub><sup>2−</sup>), magnesium (Mg<sup>2+</sup>), calcium (Ca<sup>2+</sup>) and potassium (K<sup>+</sup>). The elements that comprise salinity do not readily change and are a conservative property of seawater.<ref name=":0" /> There are many mechanisms that change salinity from a particulate form to a dissolved form and back. The known sources of sodium i.e. salts are when weathering, erosion, and dissolution of rocks are transported into rivers and deposited into the oceans.<br />
在地球的生物地球化学过程中,源和汇是元素的运动。我们海洋中盐离子的组成是:钠(Na+)、氯(Cl-)、硫酸盐(SO42-)、镁(Mg2+)、钙(Ca2+)和钾(K+)。构成盐度的元素不易变化,是海水的一种保守属性。[23]有许多机制可以将盐度从颗粒形态改变为溶解形态,然后再返回。已知的钠(即盐)来源于岩石的风化、侵蚀和溶解作用被输送到河流中并沉积到海洋中。 <br />
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The [[Mediterranean Sea]] as being Gaia's kidney is found ([http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/ here]) by Kenneth J. Hsue, a correspondence author in 2001. The "[[desiccation]]" of the Mediterranean is the evidence of a functioning kidney. Earlier "kidney functions" were performed during the "[[Deposition (geology)|deposition]] of the [[Cretaceous]] ([[Atlantic Ocean|South Atlantic]]), [[Jurassic]] ([[Gulf of Mexico]]), [[Permian–Triassic extinction event|Permo-Triassic]] ([[Europe]]), [[Devonian]] ([[Canada]]), [[Cambrian]]/[[Precambrian]] ([[Gondwana]]) saline giants."<ref>{{Cite web|url=http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/|title=Scientia Marina: List of Issues|last=http://www.webviva.com|first=Justino Martinez. Web Viva 2007|website=scimar.icm.csic.es|language=English|access-date=2017-02-04}}</ref><br />
地中海是盖亚的肾脏,由肯尼斯·J·休伊(KennethJ.Hsue)在2001年发现的。地中海的“干涸”是肾功能正常的证据。早期的“肾功能”是在“白垩纪(南大西洋)、侏罗纪(墨西哥湾)、二叠纪-三叠纪(欧洲)、泥盆纪(加拿大)、寒武纪/前寒武纪(冈瓦纳)盐沼沉积时期进行的。” <br />
[[Earthrise taken from Apollo 8 on December 24, 1968]]<br />
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[1968年12月24日阿波罗8号拍摄的地出]<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The mythical Gaia was the primal Greek goddess personifying the Earth, the Greek version of "Mother Nature" (from Ge = Earth, and Aia = <br />
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地球作为一个完整的整体,一个有生命的存在,这个观念有着悠久的传统。神话中的盖亚是拟人化地球的原始希腊女神,是希腊版本的“自然母亲”(来自 Ge = 地球,和 Aia = <br />
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===Regulation of oxygen in the atmosphere大气层的氧气调节===<br />
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PIE grandmother), or the Earth Mother. James Lovelock gave this name to his hypothesis after a suggestion from the novelist William Golding, who was living in the same village as Lovelock at the time (Bowerchalke, Wiltshire, UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry. Later, the naturalist and explorer Alexander von Humboldt recognized the coevolution of living organisms, climate, and Earth's crust. His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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派祖母,或地球母亲。詹姆斯·洛夫洛克根据小说家威廉·戈尔丁的建议给他的假设起了这个名字,他当时和洛夫洛克住在同一个村子里(英国威尔特郡鲍尔查尔克)。戈尔丁的建议是以Gea为基础的,Gea是希腊女神名字的另一种拼写,在地质学、地球物理和地球化学中,Gea是前缀。后来,博物学家和探险家亚历山大·冯·洪堡认识到生物、气候和地壳的共同进化。他的远见卓识的声明在西方没有被广泛接受,几十年后,盖亚假说受到了科学界同样类型的最初抵制。<br />
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[[File:Vostok 420ky 4curves insolation.jpg|thumb|280px|Levels of gases in the atmosphere in 420,000 years of ice core data from [[Vostok Station|Vostok, Antarctica research station]]. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
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{{See also|Geological history of oxygen}}<br />
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Also in the turn to the 20th century Aldo Leopold, pioneer in the development of modern environmental ethics and in the movement for wilderness conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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同样在20世纪之交,现代环境伦理学发展的先驱、荒野保护运动的先驱奥尔多 · 利奥波德在他的生物中心或整体的土地伦理学中提出了一个有生命的地球。<br />
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The Gaia hypothesis states that the Earth's [[Atmospheric chemistry#Atmospheric composition|atmospheric composition]] is kept at a dynamically steady state by the presence of life.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 163. {{ISBN|978-0-465-01549-8}}</ref> The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than [[noble gas]]es present in the atmosphere are either made by organisms or processed by them.<br />
盖亚假说指出,地球的大气成分由于生命的存在而保持在动态稳定的状态。大气中除惰性气体以外的所有大气气体都是由生物体制造或加工而成。<br />
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The stability of the atmosphere in Earth is not a consequence of [[chemical equilibrium]]. [[Oxygen]] is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the [[Great Oxygenation Event]].<ref name=Anabar2007>{{Cite journal| last4 = Arnold| last6 = Creaser| last3 = Lyons| first1 = A. | first2 = Y.| last9 = Scott| last2 = Duan | first3 = T. | first4 = G.| last8 = Gordon | first5 = B. | first10 = J. | first6 = R.| last10 = Garvin | first7 = A.| last11 = Buick | first8 = G. | first11 = R. | first9 = C.| title = A whiff of oxygen before the great oxidation event?| journal = Science| volume = 317| issue = 5846| year = 2007| last7 = Kaufman| pages = 1903–1906| last5 = Kendall| pmid = 17901330| last1 = Anbar | doi = 10.1126/science.1140325|bibcode = 2007Sci...317.1903A }}</ref> Since the start of the [[Cambrian]] period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume.<ref name=Berner1999>{{Cite journal<br />
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Another influence for the Gaia hypothesis and the environmental movement in general came as a side effect of the Space Race between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph Earthrise taken by astronaut William Anders in 1968 during the Apollo 8 mission became, through the Overview Effect an early symbol for the global ecology movement.<br />
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盖亚假说和环境运动的另一个影响来自于苏联和美利坚合众国之间太空竞赛的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球作为一个整体的样子。1968年,宇航员威廉 · 安德斯在阿波罗8号任务期间拍摄的地出照片,通过总体效应成为全球生态运动的早期象征。<br />
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| pmid = 10500106<br />
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| date=Sep 1999 | last1 = Berner | first1 = R. A.<br />
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| title = Atmospheric oxygen over Phanerozoic time<br />
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[[James Lovelock, 2005]]<br />
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[ James Lovelock,2005]<br />
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| volume = 96<br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the Jet Propulsion Laboratory in California on methods of detecting life on Mars. The first paper to mention it was Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life, co-authored with C.E. Giffin. A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the Pic du Midi observatory, planets like Mars or Venus had atmospheres in chemical equilibrium. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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65年9月,洛夫洛克在加利福尼亚喷气推进实验室研究探测火星生命的方法时,开始定义由生物群落控制的自我调节地球的概念。第一篇提到它的论文是行星大气:与C.E.Giffin合著的与生命存在有关的成分和其他变化。一个主要的概念是,通过大气的化学成分可以在行星尺度上探测到生命。根据picdumidi天文台收集的数据,像火星或金星这样的行星,其大气层处于化学平衡状态。这种与地球大气的差异被认为是这些行星上没有生命的证据。 <br />
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| issue = 20<br />
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| pages = 10955–10957<br />
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Lovelock formulated the Gaia Hypothesis in journal articles in 1972 and 1974, and a popular book length version of the hypothesis, published in 1979 as The Quest for Gaia, began to attract scientific and critical attention.<br />
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洛夫洛克在1972年和1974年的期刊文章中提出了盖亚假说,并在1979年出版了一本畅销书,名为《寻找盖亚》 ,开始引起科学界和批判界的关注。<br />
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| issn = 0027-8424<br />
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| journal = Proceedings of the National Academy of Sciences of the United States of America<br />
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Lovelock called it first the Earth feedback hypothesis, and it was a way to explain the fact that combinations of chemicals including oxygen and methane persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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洛夫洛克首先将其称为地球反馈假说,这是一种解释包括氧气和甲烷在内的化学物质在地球大气中保持稳定浓度的方法。洛夫洛克认为,在其他行星的大气层中探测这种组合,是一种相对可靠和廉价的探测生命的方法。<br />
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| doi = 10.1073/pnas.96.20.10955<br />
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[[Lynn Margulis]]<br />
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[琳 · 玛格丽丝]<br />
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|bibcode = 1999PNAS...9610955B }}</ref> Traces of [[Atmospheric methane|methane]] (at an amount of 100,000 tonnes produced per year)<ref name="Cicerone1988">{{cite journal |last1=Cicerone |first1=R.J. |last2=Oremland |first2=R.S. |date=1988 |title=Biogeochemical aspects of atmospheric methane |journal=Global Biogeochemical Cycles |volume=2 |issue=4 |pages=299–327 |url=//webfiles.uci.edu/setrumbo/public/Methane_papers/Cicerone_Global%20Biogeochem%20Cy_1988.pdf |doi=10.1029/GB002i004p00299 |bibcode=1988GBioC...2..299C}}</ref> should not exist, as methane is combustible in an oxygen atmosphere.<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<br />
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后来出现了其他关系,例如海洋生物产生的硫和碘的数量与陆地生物所需的数量大致相同,这些都支持了这一假说。<br />
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Dry air in the [[atmosphere of Earth]] contains roughly (by volume) 78.09% [[nitrogen]], 20.95% oxygen, 0.93% [[argon]], 0.039% [[Carbon dioxide in the Earth's atmosphere|carbon dioxide]], and small amounts of other gases including [[methane]]. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. {{citation needed|date=June 2012}}<br />
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[[地球大气]]中的干空气大约(按体积)包含78.09%[[氮]],20.95%的氧,0.93%[[氩]],0.039%[地球大气中的二氧化碳|二氧化碳]],以及少量其他气体,包括[[甲烷]]。洛夫洛克最初推测,氧气浓度超过25%会增加森林火灾和火灾的发生率。最近在石炭纪和白垩纪煤系中发现的由火引起的木炭的研究,在地质时期O<sub>2</sub>超过25%,支持了Lovelock的观点 <br />
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In 1971 microbiologist Dr. Lynn Margulis joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet. The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of eukaryotic organelles and her contributions to the endosymbiotic theory, nowadays accepted. Margulis dedicated the last of eight chapters in her book, The Symbiotic Planet, to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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1971年,微生物学家 Lynn Margulis 博士加入了 Lovelock 的行列,努力将最初的假设充实为科学证明的概念,贡献了她关于微生物如何影响大气层和地球表面不同层次的知识。这位美国生物学家也唤醒了科学界的批评,因为她倡导真核细胞器起源的理论,以及她对美国共生发源学会的贡献,现在被接受了。玛格丽丝在她的书《共生星球》中将最后八章献给了盖亚。然而,她反对对盖亚的广泛拟人化,并强调盖亚“不是一个有机体” ,而是“有机体之间相互作用的一个新兴属性”。她将盖亚定义为“组成地球表面一个巨大生态系统的一系列相互作用的生态系统”。句号”。这本书最令人难忘的“口号”实际上是由马古利斯的一个学生打趣说的: “从太空看,盖亚只是共生而已。”。<br />
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===Processing of CO<sub>2</sub>二氧化碳处理===<br />
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{{See also|Carbon cycle}}<br />
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James Lovelock called his first proposal the Gaia hypothesis but has also used the term Gaia theory. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments and provided a number of useful predictions. In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating. The principal sponsor was the National Audubon Society. Speakers included James Lovelock, George Wald, Mary Catherine Bateson, Lewis Thomas, John Todd, Donald Michael, Christopher Bird, Thomas Berry, David Abram, Michael Cohen, and William Fields. Some 500 people attended.<br />
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詹姆斯 · 洛夫洛克称他的第一个提议为盖亚假说,但也使用了盖亚理论这个术语。洛夫洛克说,最初的提法是基于观察,但仍然缺乏科学的解释。盖亚假说从那以后得到了一些科学实验的支持,并提供了一些有用的预测。事实上,更广泛的研究证明了最初的假设是错误的,在这个意义上,不是生命本身,而是整个地球系统在调节。主要赞助者是奥杜邦学会。讲者包括 James Lovelock、 George Wald、 Mary Catherine Bateson、 Lewis Thomas、 John Todd、 Donald Michael、 Christopher Bird、 Thomas Berry、 David Abram、 Michael Cohen 和 William Fields。大约有500人参加。<br />
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Gaia scientists see the participation of living organisms in the [[carbon cycle]] as one of the complex processes that maintain conditions suitable for life. The only significant natural source of [[Carbon dioxide in Earth's atmosphere|atmospheric carbon dioxide]] ([[Carbon dioxide|CO<sub>2</sub>]]) is [[volcanic activity]], while the only significant removal is through the precipitation of [[carbonate rocks]].<ref name="Karhu1996">{{cite journal | author = Karhu, J.A. | author2 = Holland, H.D. | date = 1 October 1996 | title = Carbon isotopes and the rise of atmospheric oxygen | journal = [[Geology (journal)|Geology]] | volume = 24 | issue = 10 | pages = 867–870 | doi = 10.1130/0091-7613(1996)024<0867:CIATRO>2.3.CO;2|bibcode = 1996Geo....24..867K | ref = harv}}</ref> Carbon precipitation, solution and [[Carbon fixation|fixation]] are influenced by the [[bacteria]] and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
盖亚的科学家认为,生物参与[[碳循环]是维持适宜生命条件的复杂过程之一。[[地球大气中的二氧化碳|大气二氧化碳]]([[二氧化碳| CO2]])的唯一重要自然来源是[[火山活动]],而唯一显著的清除是通过[[碳酸盐岩]]的沉淀,溶液和[[固碳|固碳]]受土壤中的[[细菌]]和植物根的影响,它们改善了气体循环,珊瑚礁中碳酸钙以固体形式沉积在海底。碳酸钙被生物用来制造含碳测试和贝壳。一旦死亡,这些生物的壳就会落到海底,在那里它们会产生白垩和石灰岩的沉积物。 <br />
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One of these organisms is ''[[Emiliania huxleyi]]'', an abundant [[coccolithophore]] [[algae]] which also has a role in the formation of [[cloud]]s.<ref name="Harding2006">{{cite book |author=Harding, Stephan |title=Animate Earth |publisher=Chelsea Green Publishing |date=2006 |pages=65 |isbn=978-1-933392-29-5 }}</ref> CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants.{{citation needed|date=July 2015}} Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean [[algal bloom]]s are also increasing.<ref>{{Cite web | date = 12 September 2007 | title = Interagency Report Says Harmful Algal Blooms Increasing | url = http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | url-status = dead | archiveurl = https://web.archive.org/web/20080209234239/http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | archivedate = 9 February 2008 }}</ref><br />
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In 1988, climatologist Stephen Schneider organised a conference of the American Geophysical Union. The first Chapman Conference on Gaia,<br />
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在1988年,气候学家史蒂芬·史奈德组织了一次美国美国地球物理联盟协会的会议。关于盖亚的第一次查普曼会议,<br />
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[[Lichen]] and other organisms accelerate the [[weathering]] of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the Daisyworld Model (and its modifications, above) as evidence against most of these criticisms.<br />
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然而,洛夫洛克和其他支持盖亚理论的科学家确实试图反驳这样一种说法,即这种假设不科学,因为不可能通过控制实验来检验它。例如,针对盖亚是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修正,上文)作为反驳大多数这些批评的证据。<br />
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==History历史==<br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of teleologism ceased, following this conference.<br />
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洛夫洛克谨慎地提出了盖亚假说的一个版本,该假说没有声称盖亚有意或有意地在她的环境中维持生命赖以生存的复杂平衡。看起来,盖亚“故意”行为的说法只是他那本广受欢迎的书中的一个比喻性陈述,并不是字面意义上的理解。这种对盖亚假说的新陈述更能为科学界所接受。在这次会议之后,大多数关于目的论的指责都停止了。<br />
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===Precedents先例===<br />
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[[File:NASA-Apollo8-Dec24-Earthrise.jpg|thumb|''[[Earthrise]]'' taken from [[Apollo 8]] on December 24, 1968]]<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000, the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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到2000年6月23日在西班牙巴伦西亚举行关于盖亚假说的第二次查普曼会议时,情况发生了重大变化。与其讨论盖亚的目的论观点,或盖亚假说的“类型” ,不如将重点放在具体的机制上,通过这些机制,基本的短期内稳态在一个重要的进化的长期结构变化的框架内得以维持。<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The [[Gaia (mythology)|mythical Gaia]] was the primal Greek goddess personifying the [[Earth]], the Greek version of "[[Mother Nature]]" (from Ge = Earth, and Aia = <br />
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[[PIE]] grandmother), or the [[Earth Mother]]. James Lovelock gave this name to his hypothesis after a suggestion from the novelist [[William Golding]], who was living in the same village as Lovelock at the time ([[Bowerchalke]], [[Wiltshire]], UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry.<ref name=vanish09 /> Golding later made reference to Gaia in his [[Nobel prize]] acceptance speech.<br />
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The major questions were:<br />
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主要的问题是:<br />
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In the eighteenth century, as [[geology]] consolidated as a modern science, [[James Hutton]] maintained that geological and biological processes are interlinked.<ref name=CapraWeb>{{cite book |author=Capra, Fritjof |title=The web of life: a new scientific understanding of living systems |publisher=Anchor Books |location=Garden City, N.Y |date=1996 |page=[https://archive.org/details/weboflifenewscie00capr/page/23 23] |isbn=978-0-385-47675-1 |url=https://archive.org/details/weboflifenewscie00capr/page/23 }}</ref> Later, the [[naturalist]] and explorer [[Alexander von Humboldt]] recognized the coevolution of living organisms, climate, and Earth's crust.<ref name=CapraWeb /> In the twentieth century, [[Vladimir Vernadsky]] formulated a theory of Earth's development that is now one of the foundations of ecology. Vernadsky was a Ukrainian [[geochemist]] and was one of the first scientists to recognize that the oxygen, nitrogen, and carbon dioxide in the Earth's atmosphere result from biological processes. During the 1920s he published works arguing that living organisms could reshape the planet as surely as any physical force. Vernadsky was a pioneer of the scientific bases for the environmental sciences.<ref>S.R. Weart, 2003, ''The Discovery of Global Warming'', Cambridge, Harvard Press</ref> His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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"How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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“被称为盖亚的全球生物地球化学/气候系统是如何及时发生变化的?它的历史是什么?盖亚能够在一个时间尺度上保持系统的稳定性,但是在更长的时间尺度上仍然经历矢量变化吗?如何利用地质记录来检验这些问题? ”<br />
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"What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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“盖亚的结构是什么?这些反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由在任何特定时间进行的学科研究务实地决定的,还是有一些部分应该被认为是最真实的,以了解盖亚随着时间的推移包含进化中的生物体?盖亚系统这些不同部分之间的反馈是什么? 对盖亚作为全球生态系统的结构和生命的生产力来说,物质的近乎封闭意味着什么? ”<br />
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Also in the turn to the 20th century [[Aldo Leopold]], pioneer in the development of modern [[environmental ethics]] and in the movement for [[wilderness]] conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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"How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
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“盖亚过程和现象的模型如何与现实相关,它们如何帮助解决和理解盖亚?雏菊世界的成果如何转移到现实世界?什么是“雏菊”的主要候选人?我们发现雏菊与否对盖亚理论重要吗?我们应该怎样寻找雏菊,我们应该加紧寻找吗?如何利用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖亚机制? ”<br />
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{{quotation|It is at least not impossible to regard the earth's parts—soil, mountains, rivers, atmosphere etc,—as organs or parts of organs of a coordinated whole, each part with its definite function. And if we could see this whole, as a whole, through a great period of time, we might perceive not only organs with coordinated functions, but possibly also that process of consumption as replacement which in biology we call metabolism, or growth. In such case we would have all the visible attributes of a living thing, which we do not realize to be such because it is too big, and its life processes too slow.| Stephan Harding | ''Animate Earth''.<ref>Harding, Stephan. ''Animate Earth Science, Intuition and Gaia''. Chelsea Green Publishing, 2006, p. 44. {{ISBN|1-933392-29-0}}</ref>}}<br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise entropy production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
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1997年,泰勒·沃尔克认为,盖亚系统几乎不可避免地会产生,这是一种向远离平衡的稳态演化的结果,这种平衡状态使熵产生最大化,克莱顿(2004)同意这样的说法:“自稳态行为可以从与行星反照率相关的MEP状态中产生”;“……一个如盖亚假说所述,处于MEP状态的生物地球很可能导致地球系统在长时间尺度上的近稳态行为。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。<br />
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Another influence for the Gaia hypothesis and the [[environmental movement]] in general came as a side effect of the [[Space Race]] between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph ''[[Earthrise]]'' taken by astronaut [[William Anders]] in 1968 during the [[Apollo 8]] mission became, through the [[Overview Effect]] an early symbol for the global ecology movement.<ref>[http://digitaljournalist.org/issue0309/lm11.html 100 Photographs that Changed the World by Life - The Digital Journalist]</ref><br />
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盖亚假说和[[环境运动]]的另一个总体影响来自苏联和美利坚合众国之间[[太空竞赛]]的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球的整体面貌。1968年宇航员[[William Anders]]在[[Apollo 8]]任务期间拍摄的照片“[[地球升起]”,通过[[概述效果]]成为全球生态运动的早期标志<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<br />
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第四次关于盖亚假说的国际会议,由北弗吉尼亚地区公园管理局和其他机构主办,于2006年10月在弗吉尼亚州乔治梅森大学的阿灵顿校区举行。<br />
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===Formulation of the hypothesis假说形成===<br />
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[[File:James Lovelock in 2005.jpg|thumb|[[James Lovelock]], 2005]]<br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
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马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。Lynn Margulis是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the [[Jet Propulsion Laboratory]] in California on methods of detecting [[life on Mars (planet)|life on Mars]].<ref name="Lovelock1965">{{cite journal | author = Lovelock, J.E. | date = 1965 | title = A physical basis for life detection experiments | journal = [[Nature (journal)|Nature]] | volume = 207 | issue = 7 | pages = 568–570 | doi = 10.1038/207568a0 | pmid=5883628|bibcode = 1965Natur.207..568L | ref = harv}}</ref><ref>{{Cite web |url=http://www.jameslovelock.org/page4.html |title=Geophysiology |access-date=2007-05-05 |archive-url=https://web.archive.org/web/20070506073502/http://www.jameslovelock.org/page4.html |archive-date=2007-05-06 |url-status=dead }}</ref> The first paper to mention it was ''Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life'', co-authored with C.E. Giffin.<ref>{{cite journal | author1 = Lovelock, J.E. | author2 = Giffin, C.E. | date = 1969 | title = Planetary Atmospheres: Compositional and other changes associated with the presence of Life | journal = Advances in the Astronautical Sciences | volume = 25 | pages = 179–193 | isbn = 978-0-87703-028-7 | ref = harv}}</ref> A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the [[Pic du Midi de Bigorre|Pic du Midi observatory]], planets like Mars or Venus had atmospheres in [[chemical equilibrium]]. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
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这次会议将盖亚假说作为一种科学和隐喻的手段,来理解我们如何开始解决21世纪的问题,如气候变化和持续的环境破坏。<br />
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Lovelock formulated the ''Gaia Hypothesis'' in journal articles in 1972<ref name="J1972">{{cite journal | author = J. E. Lovelock | title = Gaia as seen through the atmosphere | date = 1972 | journal = [[Atmospheric Environment]] | volume = 6 | issue = 8 | pages = 579–580 | doi = 10.1016/0004-6981(72)90076-5 | ref = harv|bibcode = 1972AtmEn...6..579L }}</ref> and 1974,<ref name="lovelock1974" /> followed by a popularizing 1979 book ''Gaia: A new look at life on Earth''. An article in the ''[[New Scientist]]'' of February 6, 1975,<ref>Lovelock, John and Sidney Epton, (February 8, 1975). "The quest for Gaia". [https://books.google.com/books?id=pnV6UYEkU4YC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false New Scientist], p. 304.</ref> and a popular book length version of the hypothesis, published in 1979 as ''The Quest for Gaia'', began to attract scientific and critical attention.<br />
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Lovelock called it first the Earth feedback hypothesis,<ref name="Lovelock01">{{harvnb|Lovelock, James|2001}}</ref> and it was a way to explain the fact that combinations of chemicals including [[oxygen]] and [[methane]] persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as Ford Doolittle, Richard Dawkins and Stephen Jay Gould. Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists, He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as autopoietic or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole. With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<br />
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在最初几乎没有引起科学家的注意之后(从1969年到1977年) ,有一段时间,最初的盖亚假说受到了一些科学家的批评,如福特杜利特,理查德道金斯和史蒂芬·古尔德。洛夫洛克说,因为他的假说是以一位希腊女神的名字命名的,并得到许多非科学家的拥护,他想知道实现自我调节体内平衡的实际机制。在为盖亚辩护时,戴维•阿布拉姆认为,古尔德忽视了一个事实,即“机制”本身就是一个隐喻——尽管这个隐喻极其常见,而且往往不为人所知——这个隐喻让我们把自然和生命系统看作是由外部组织和建造的机器(而不是自动生成或自组织现象)。根据阿布拉姆的说法,机械隐喻使我们忽略了生命实体的活跃性或代表性,而盖亚假说的有机隐喻强调了生物群和整个生物圈的活跃性。关于盖亚的因果关系,洛夫洛克认为没有单一的机制是负责任的,各种已知机制之间的联系可能永远不会被人知道,这在生物学和生态学的其他领域是理所当然地被接受的,并且由于其他原因,特定的敌意是保留给他自己的假设的。<br />
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[[File:Lynn Margulis.jpg|thumb|left|[[Lynn Margulis]]]]<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of greedy reductionism in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<br />
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除了澄清他的语言和理解什么是生命形式,洛夫洛克自己把大部分的批评归因于他的批评者缺乏对非线性数学的理解,以及贪婪还原主义的线性化形式,在这种形式中,所有事件都必须立即归因于事件发生之前的特定原因。他还表示,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,以及一些自我调节现象可能无法在数学上解释。<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<ref>{{cite journal | first1=W.D. | last1=Hamilton | first2=T.M. | last2=Lenton | title=Spora and Gaia: how microbes fly with their clouds | journal=Ethology Ecology & Evolution | volume=10 | pages=1–16 | date=1998 | issue=1 | url=http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | format=PDF | doi=10.1080/08927014.1998.9522867 | ref=harv | url-status=dead | archiveurl=https://web.archive.org/web/20110723055017/http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | archivedate=2011-07-23 }}</ref><br />
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Evolutionary biologist W. D. Hamilton called the concept of Gaia Copernican, adding that it would take another Newton to explain how Gaian self-regulation takes place through Darwinian natural selection. More recently Ford Doolittle building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis. <br />
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进化生物学家W.D.Hamilton称盖亚为哥白尼的概念,并补充说,需要另一个牛顿来解释盖亚的自我调节是如何通过达尔文的自然选择发生的。最近,Ford Doolittle在他和Inkpen的ITSNTS(这是歌手而不是歌曲)的建议中提出,差异持续性可以在自然选择进化中起到与差异生殖相似的作用,从而为自然选择理论和盖亚假说之间提供了一种可能的调和。 <br />
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In 1971 [[microbiologist]] Dr. [[Lynn Margulis]] joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet.<ref name="Turney, Jon 2003">{{cite book |author=Turney, Jon |title=Lovelock and Gaia: Signs of Life |publisher=Icon Books |location=UK |date=2003 |isbn=978-1-84046-458-0 |url-access=registration |url=https://archive.org/details/lovelockgaiasign0000turn }}</ref> The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of [[eukaryote|eukaryotic]] [[organelle]]s and her contributions to the [[endosymbiotic theory]], nowadays accepted. Margulis dedicated the last of eight chapters in her book, ''The Symbiotic Planet'', to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal Climatic Change in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it. to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background" The CLAW hypothesis, In 2009 the Medea hypothesis was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<br />
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盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论据是,生命对环境产生了有害或不稳定的影响,而不是采取行动加以调节。为了“令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在背景下。”爪假说,2009年提出的美狄亚假说:生命对行星条件有高度有害的(生物杀灭)影响,与盖亚假说直接相反。 <br />
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James Lovelock called his first proposal the ''Gaia hypothesis'' but has also used the term ''Gaia theory''. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments<ref name="J1990">{{cite journal | author = J. E. Lovelock | title = Hands up for the Gaia hypothesis | date = 1990 | journal = [[Nature (journal)|Nature]] | volume = 344 | issue = 6262 | pages = 100–2 | doi = 10.1038/344100a0|bibcode = 1990Natur.344..100L | ref = harv}}</ref> and provided a number of useful predictions.<ref name="Volk2003">{{cite book |author=Volk, Tyler |title=Gaia's Body: Toward a Physiology of Earth |publisher=[[MIT Press]] |location=Cambridge, Massachusetts |date=2003 |isbn=978-0-262-72042-7 }}</ref> In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating.<ref name="vanishing255"/><br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it". Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works". This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<br />
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2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚假说是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚假说的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新想法,并倡导一种整体的方法来研究地球”。在其他地方,他提出了自己的结论:“盖亚假说并不是我们这个世界如何运转的精确图像”。这种说法需要被理解为是指盖亚假说的“强”和“中”形式,生物群遵循的原则是使地球成为最佳(强度5)或有利于生命(强度4),或是作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚假说的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚假说的两种较弱的形式:共同进化的盖亚假说和有影响力的盖亚假说,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚假说”一词是没有用的,两种形式已经被自然选择和适应过程所接受和解释。<br />
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===First Gaia conference第一次盖亚会议===<br />
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In 1985, the first public symposium on the Gaia hypothesis, ''Is The Earth A Living Organism?'' was held at [[University of Massachusetts Amherst]], August 1–6.<ref>{{cite news |last=Joseph |first=Lawrence E. |title=Britain's Whole Earth Guru |work=The New York Times Magazine |date=November 23, 1986 |url=https://www.nytimes.com/1986/11/23/magazine/britain-s-whole-earth-guru.html |accessdate=1 December 2013}}</ref> The principal sponsor was the [[National Audubon Society]]. Speakers included James Lovelock, [[George Wald]], [[Mary Catherine Bateson]], [[Lewis Thomas]], [[John Todd (Canadian biologist)|John Todd]], Donald Michael, [[Christopher Bird]], [[Thomas Berry]], [[David Abram]], [[Michael A. Cohen|Michael Cohen]], and William Fields. Some 500 people attended.<ref>Bunyard, Peter (1996), "Gaia in Action: Science of the Living Earth" (Floris Books)</ref><br />
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1985年,关于盖亚假说的第一次公开研讨会,“地球是一个活的有机体吗?”在马萨诸塞大学阿默斯特举行 <br />
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===Second Gaia conference第二次盖亚会议===<br />
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In 1988, [[climatology|climatologist]] [[Stephen Schneider]] organised a conference of the [[American Geophysical Union]]. The first Chapman Conference on Gaia,<ref name="ReferenceB"/> was held in San Diego, California on March 7, 1988.<br />
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1988年,climatology和Stephen Schneider组织了一次美国地球物理联合会会议。关于盖亚的第一次查普曼会议 <br />
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During the "philosophical foundations" session of the conference, [[David Abram]] spoke on the influence of metaphor in science, and of the Gaia hypothesis as offering a new and potentially game-changing metaphorics, while [[James Kirchner]] criticised the Gaia hypothesis for its imprecision. Kirchner claimed that Lovelock and Margulis had not presented one Gaia hypothesis, but four -<br />
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在会议的“哲学基础”会议上,David Abram谈到了隐喻在科学中的影响,盖亚假说提供了一种新的、可能改变游戏规则的隐喻,而James Kirchner则批评盖亚假说的不精确性。基什纳声称,洛夫洛克和马古利斯提出的盖亚假说不是一个,而是四个- <br />
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* [[Coevolution|CoEvolutionary]] Gaia: that life and the environment had evolved in a coupled way. Kirchner claimed that this was already accepted scientifically and was not new.<br />
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* [[Homeostatic]] Gaia: that life maintained the stability of the natural environment, and that this stability enabled life to continue to exist.<br />
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* [[Geophysics|Geophysical]] Gaia: that the Gaia hypothesis generated interest in geophysical cycles and therefore led to interesting new research in terrestrial geophysical dynamics.<br />
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* Optimising Gaia: that Gaia shaped the planet in a way that made it an optimal environment for life as a whole. Kirchner claimed that this was not testable and therefore was not scientific.<br />
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盖亚:生命和环境是以耦合的方式进化的。基什内尔声称,这已经被科学界接受,并不是什么新鲜事。 <br />
盖亚:生命维持着自然环境的稳定,这种稳定性使生命得以继续存在。 <br />
盖亚:盖亚假说引起了人们对地球物理周期的兴趣,因此导致了地球物理动力学中有趣的新研究。 <br />
优化盖亚:盖亚塑造了地球,使之成为整个生命的最佳环境。基什内尔声称,这是不可测试的,因此是不科学的。 <br />
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Of Homeostatic Gaia, Kirchner recognised two alternatives. "Weak Gaia" asserted that life tends to make the environment stable for the flourishing of all life. "Strong Gaia" according to Kirchner, asserted that life tends to make the environment stable, ''to enable'' the flourishing of all life. Strong Gaia, Kirchner claimed, was untestable and therefore not scientific.<ref>{{cite journal | bibcode=1989RvGeo..27..223K | doi = 10.1029/RG027i002p00223 | title=The Gaia hypothesis: Can it be tested? | date=1989 | last1=Kirchner | first1=James W. | journal=Reviews of Geophysics | volume=27 | issue=2 | pages=223 | ref=harv}}</ref><br />
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基什内尔发现了两种选择“软弱的盖亚”断言,为了所有生命的繁衍,生命往往会使环境变得稳定根据基什内尔的说法,“强大的盖亚”断言,生命趋向于使环境稳定,“使”所有生命繁荣昌盛。基什内尔声称,强大的盖亚是不稳定的,因此不科学。 <br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the [[Daisyworld]] Model (and its modifications, above) as evidence against most of these criticisms.<ref name="daisyworld"/> Lovelock said that the Daisyworld model "demonstrates that self-regulation of the global environment can emerge from competition amongst types of life altering their local environment in different ways".<ref>{{cite journal | pmid=10968941 | date=2000 | last1=Lenton | first1=TM | last2=Lovelock | first2=JE | s2cid=5486128 | title=Daisyworld is Darwinian: Constraints on adaptation are important for planetary self-regulation | volume=206 | issue=1 | pages=109–14 | doi=10.1006/jtbi.2000.2105 | journal=Journal of Theoretical Biology | ref=harv}}</ref><br />
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然而,洛夫洛克和其他支持盖亚的科学家,确实试图反驳这种说法,即这个假设是不科学的,因为不可能通过受控实验来检验它。例如,针对盖亚是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修改,洛夫洛克说,雏菊世界模型“证明了全球环境的自我调节可以通过不同方式改变当地环境的生活类型之间的竞争产生”。 <br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of [[teleology|teleologism]] ceased, following this conference.<br />
洛夫洛克谨慎地提出了盖亚假说的一个版本,没有声称盖亚有意或有意识地维持着生命生存所需的复杂平衡。看来盖亚“故意”的行为是他最受欢迎的第一本书中的隐喻性陈述,并不是字面意思。盖亚假说的这一新说法更为科学界所接受。在这次会议之后,[[目的论|目的论]]的大多数指控都停止了。<br />
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===Third Gaia conference第三次盖亚会议===<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000,<ref>{{cite news|last=Simón|first=Federico|title=GEOLOGÍA Enfoque multidisciplinar La hipótesis Gaia madura en Valencia con los últimos avances científicos|journal=El País|date=21 June 2000|url=http://elpais.com/diario/2000/06/21/futuro/961538404_850215.html|accessdate=1 December 2013|language=spanish}}</ref> the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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The major questions were:<ref>{{cite web|title=General Information Chapman Conference on the Gaia Hypothesis University of Valencia Valencia, Spain June 19-23, 2000 (Monday through Friday) |url=http://www.agu.org/meetings/chapman/chapman_archive/cc00bcall.html |work=AGU Meetings |accessdate=7 January 2017 |author=American Geophysical Union }}</ref><br />
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# "How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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# "What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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# "How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
“被称为盖亚的全球生物地球化学/气候系统是如何随时间变化的?它的历史是什么?盖亚能在一个时间尺度上保持系统的稳定性,但在较长的时间尺度上仍能经历向量变化吗?如何利用地质记录来检验这些问题?” <br />
“盖亚的结构是什么?反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由任何给定时间正在进行的任何学科研究实际确定的,还是有一组应该被视为最真实的部分来理解盖亚,即随着时间的推移包含进化中的有机体?盖亚系统的这些不同部分之间的反馈是什么?物质的接近封闭对盖亚作为全球生态系统的结构和生命的生产力意味着什么?” <br />
“盖亚过程和现象的模型如何与现实联系起来,它们如何帮助解决和理解盖亚?雏菊世界的结果如何传递到真实世界?“雏菊”的主要候选对象是什么?我们是否找到雏菊对盖亚理论有意义吗?我们应该如何寻找雏菊,我们应该加强搜索?如何使用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖安机制?” <br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise [[entropy]] production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
1997年,泰勒·沃尔克认为,盖安系统几乎不可避免地会产生,这是朝着使熵产量最大化的远非平衡平衡平衡状态演化的结果,克莱顿(2004)同意这样的说法:“自稳行为可以从与行星反照率相关的MEP状态中产生”;“……生物地球在MEP状态下的行为很可能导致地球系统在长时间尺度上的近稳态行为,正如盖亚假说所述”。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。 <br />
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===Fourth Gaia conference第四次盖亚会议===<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<ref>{{cite web|title=Gaia Theory Conference at George Mason University Law School|url=http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|accessdate=1 December 2013|author=Official Site of Arlington County Virginia|archive-url=https://web.archive.org/web/20131203043657/http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|archive-date=2013-12-03|url-status=dead}}</ref><br />
第四届盖亚假说国际会议于2006年10月在乔治梅森大学阿灵顿分校举行,会议由北弗吉尼亚州公园管理局和其他机构赞助。 <br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。林恩 马古拉斯是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
这次会议将盖亚假说作为一种科学和隐喻来探讨,以此来理解我们如何着手解决21世纪的问题,如气候变化和持续的环境破坏<br />
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==Criticism批评==<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as [[Ford Doolittle]],<ref name=":1">{{Cite journal|last=Doolittle|first=W. F.|year=1981|title=Is Nature Really Motherly|url=|journal=The Coevolution Quarterly|volume=Spring|pages=58–63|via=}}</ref> [[Richard Dawkins]]<ref name=":2">{{Cite book|title=The Extended Phenotype: the Long Reach of the Gene|last=Dawkins|first=Richard|publisher=Oxford University Press|year=1982|isbn=978-0-19-286088-0|location=|pages=}}</ref> and [[Stephen Jay Gould]].<ref name="ReferenceB">Turney, Jon. "Lovelock and Gaia: Signs of Life" (Revolutions in Science)</ref> Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists,<ref name="Lovelock01"/> the Gaia hypothesis was interpreted as a [[neo-Pagan]] [[religion]]. Many scientists in particular also criticised the approach taken in his popular book ''Gaia, a New Look at Life on Earth'' for being [[teleology|teleological]]—a belief that things are purposeful and aimed towards a goal. Responding to this critique in 1990, Lovelock stated, "Nowhere in our writings do we express the idea that planetary self-regulation is purposeful, or involves foresight or planning by the [[biota (ecology)|biota]]".<br />
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最初很少受到科学家的关注(从1969年到1977年),此后的一段时间里,最初的盖亚假说受到了许多科学家的批评,比如福特·杜利特,理查德·道金斯和斯蒂芬·杰伊·古尔德洛夫洛克曾说过,因为他的假设是以希腊女神的名字命名的,新盖亚假说被许多非教派的科学家解释为。特别是许多科学家还批评了他的畅销书《盖亚》中采用的方法,认为地球上的生命是目的论的,认为事物是有目的的,是有目的的。洛夫洛克在1990年回应这一批评时说:“在我们的著作中我们没有任何地方表达行星自我调节是有目的的,或涉及生物群的远见或计划。”<br />
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[[Stephen Jay Gould]] criticised Gaia as being "a metaphor, not a mechanism."<ref name="Gould 1997">{{cite journal |author=Gould S.J. |title=Kropotkin was no crackpot |journal=Natural History |volume=106 |pages=12–21 |date=June 1997 |url=http://libcom.org/library/kropotkin-was-no-crackpot |ref=harv}}</ref> He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as [[autopoiesis|autopoietic]] or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole.<ref>Abram, D. (1988) "The Mechanical and the Organic: On the Impact of Metaphor in Science" in Scientists on Gaia, edited by Stephen Schneider and Penelope Boston, Cambridge, Massachusetts: MIT Press, 1991</ref><ref>{{cite web|url=http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |title=The Mechanical and the Organic |accessdate=August 27, 2012 |url-status=dead |archiveurl=https://web.archive.org/web/20120223165936/http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |archivedate=February 23, 2012 }}</ref> With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<ref name="Lovelock, James 2001">Lovelock, James (2001), ''Homage to Gaia: The Life of an Independent Scientist'' (Oxford University Press)</ref><br />
史蒂芬·杰伊·古尔德批评盖亚是“一种隐喻,而不是一种机制。”他想知道实现自我调节内稳态的实际机制。在为盖亚辩护时,大卫·艾布拉姆认为古尔德忽略了一个事实,即“机制”本身就是一个隐喻——尽管这是一个非常常见且常常未被人认识的隐喻——它使我们把自然和生命系统看作是从外部组织和建造的机器(而不是自动或自组织的)现象)。艾布拉姆认为,机械隐喻使我们忽视了生命实体的活动性或能动性,而盖亚假说的有机体隐喻强调了生物群和生物圈作为一个整体的能动性。关于盖亚的因果关系,洛夫洛克认为没有单一的机制负责各种已知机制之间的联系可能永远不为人所知,这一点在其他生物学和生态学领域都是理所当然的,而具体的敌意是出于其他原因留给他自己的假设的<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of [[greedy reductionism]] in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<ref name="Lovelock, James 2001"/><br />
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除了澄清自己的语言和对生命形式的理解之外,洛夫洛克自己将大部分批评归咎于批评家对非线性数学的缺乏理解,以及贪婪还原论的线性化形式,在这种形式中,所有事件都必须在事实发生之前立即归因于特定的原因。他还指出,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,有些自我调节的现象可能无法用数学解释 <br />
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===Natural selection and evolution自然选择和进化===<br />
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Lovelock has suggested that global biological feedback mechanisms could evolve by [[natural selection]], stating that organisms that improve their environment for their survival do better than those that damage their environment. However, in the early 1980s, [[Ford Doolittle|W. Ford Doolittle]] and [[Richard Dawkins]] separately argued against this aspect of Gaia. Doolittle argued that nothing in the [[genome]] of individual organisms could provide the feedback mechanisms proposed by Lovelock, and therefore the Gaia hypothesis proposed no plausible mechanism and was unscientific.<ref name=":1" /> Dawkins meanwhile stated that for organisms to act in concert would require foresight and planning, which is contrary to the current scientific understanding of evolution.<ref name=":2" /> Like Doolittle, he also rejected the possibility that feedback loops could stabilize the system.<br />
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洛夫洛克提出,全球生物反馈机制可以通过自然选择而进化,他指出,为生存而改善环境的生物比那些破坏环境的生物做得更好。然而,在20世纪80年代早期,W·福特·杜立德和理查德·道金斯分别反对盖亚的这一方面。杜立德认为,单个生物体的基因组中没有任何东西能够提供洛夫洛克提出的反馈机制,因此盖亚假说没有提出任何合理的机制,是不科学的。道金斯同时指出,要使有机体协同行动,就需要有远见和计划,这与当前科学界对进化论的理解相悖和杜立德一样,他也拒绝了反馈回路可以稳定系统的可能性。<br />
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[[Lynn Margulis]], a microbiologist who collaborated with Lovelock in supporting the Gaia hypothesis, argued in 1999, that "[[Charles Darwin|Darwin]]'s grand vision was not wrong, only incomplete. In accentuating the direct competition between individuals for resources as the primary selection mechanism, Darwin (and especially his followers) created the impression that the environment was simply a static arena". She wrote that the composition of the Earth's atmosphere, hydrosphere, and lithosphere are regulated around "set points" as in [[homeostasis]], but those set points change with time.<ref name="ReferenceA">Margulis, Lynn. Symbiotic Planet: A New Look At Evolution. Houston: Basic Book 1999</ref><br />
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Lynn Margulis,一位与Lovelock合作支持盖亚假说的微生物学家,在1999年指出,“达尔文的宏伟愿景没有错,只是不完整。达尔文(特别是他的追随者)强调个人之间对资源的直接竞争是主要的选择机制,他给人的印象是环境只是一个静态的竞技场”。她写道,地球大气、水圈和岩石圈的组成都是围绕着“设定点”来调节的,就像在体内平衡中一样,但是这些设定点会随着时间的推移而变化 <br />
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Evolutionary biologist [[W. D. Hamilton]] called the concept of Gaia [[Nicolaus Copernicus|Copernican]], adding that it would take another [[Isaac Newton|Newton]] to explain how Gaian self-regulation takes place through Darwinian [[natural selection]].<ref name=vanish09>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, pp. 195-197. {{ISBN|978-0-465-01549-8}}</ref>{{better source|date=September 2012|reason=it should be possible to find the original place where Hamilton said this}} More recently [[Ford Doolittle]] building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal<ref name="ITSNTS">Doolittle WF, Inkpen SA. Processes and patterns of interaction as units of selection: An introduction to ITSNTS thinking. [https://www.pnas.org/content/115/16/4006 PNAS April 17, 2018 115 (16)] 4006-4014 </ref> proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis<ref name="Darwinizing Gaia">Doolittle WF. Darwinizing Gaia. [https://doi.org/10.1016/j.jtbi.2017.02.015 Journal of Theoretical BiologyVolume 434], 7 December 2017, Pages 11-19 </ref>. <br />
进化生物学家汉密尔顿称盖亚哥白尼为盖亚的概念,他补充说,需要另一个牛顿来解释盖安的自我调节是如何通过达尔文的自然选择发生的。通过自然选择在进化过程中的繁殖,从而为自然选择理论和盖亚假说提供了可能的调和。 <br />
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===Criticism in the 21st century21世纪的批评===<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal ''Climatic Change'' in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it.<ref name="kirchner2002"/><ref name="volk2002"/> Several recent books have criticised the Gaia hypothesis, expressing views ranging from "... the Gaia hypothesis lacks unambiguous observational support and has significant theoretical difficulties"<ref>{{cite book |last=Waltham |first=David |authorlink=David Waltham |date=2014 |title=Lucky Planet: Why Earth is Exceptional – and What that Means for Life in the Universe |url=https://archive.org/details/luckyplanetwhyea0000walt |location= |publisher=Icon Books |page= |isbn=9781848316560 |accessdate= |url-access=registration }}</ref> to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background"<ref name="beerling2007"/> to "The Gaia hypothesis is supported neither by evolutionary theory nor by the empirical evidence of the geological record".<ref>{{cite book |last1=Cockell |first1=Charles |authorlink1=Charles Cockell |last2=Corfield |first2=Richard |last3=Dise |first3= Nancy |last4=Edwards |first4=Neil |last5=Harris |first5=Nigel |date=2008 |title= An Introduction to the Earth-Life System |url= http://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/palaeontology-and-life-history/introduction-earth-life-system |location=Cambridge (UK) |publisher= Cambridge University Press |page= |isbn= 9780521729536 |accessdate= }}</ref> The [[CLAW hypothesis]],<ref name="CLAW87" /> initially suggested as a potential example of direct Gaian feedback, has subsequently been found to be less credible as understanding of [[cloud condensation nuclei]] has improved.<ref>{{Citation |last1= Quinn |first1=P.K. |last2= Bates |first2=T.S. |title =The case against climate regulation via oceanic phytoplankton sulphur emissions |journal =Nature |volume=480 |issue=7375 |pages =51–56 |date = 2011 |doi=10.1038/nature10580|bibcode = 2011Natur.480...51Q |pmid=22129724|url=https://zenodo.org/record/1233319 }}</ref> In 2009 the [[Medea hypothesis]] was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<ref>Peter Ward (2009), ''The Medea Hypothesis: Is Life on Earth Ultimately Self-Destructive?'', {{ISBN|0-691-13075-2}}</ref><br />
盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论点是许多例子,其中生命对环境产生了有害或不稳定的影响,而不是采取行动来调节它。最近几本书批评了盖亚假说,表达了从“盖亚假说缺乏明确的观察支持,并且有重大的理论困难“到”令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在背景中“到”盖亚假说既没有进化论的支持,也没有地质记录的经验证据的支持。爪假说最初被认为是盖安直接反馈的一个潜在例子,后来被发现对云的理解不那么可信凝聚核已经得到了改善2009年,美狄亚假说被提出:生命对行星的状况有非常有害的(杀生的)影响,这与盖亚假说直接相反 <br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it".<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=209 |isbn=9780691121581 |accessdate= }}</ref> Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works".<ref>{{Citation |last= Tyrrell |first = Toby |title =Gaia: the verdict is… |journal = New Scientist |volume = 220 |issue = 2940 |pages = 30–31 |date= 26 October 2013 |doi=10.1016/s0262-4079(13)62532-4}}</ref> This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=208 |isbn=9780691121581 |accessdate= }}</ref><br />
2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新思想,并倡导一种研究地球的整体方法。”在其他地方,他提出了自己的结论:“盖亚假说并不是一个关于如何进行的精确描述我们的世界在运转。”这种说法需要被理解为是指盖亚的“强大”和“温和”形式,生物群遵循的原则是使地球处于最佳状态(强度5)或有利于生命(强度4),或者它作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚的两种较弱的形式共同进化盖亚和有影响力的盖亚,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚”一词是没有用的两种形式已经被自然选择和适应过程所接受和解释 <br />
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范畴: 生态学理论<br />
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Category:Superorganisms<br />
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{{Portal|Environment|Earth sciences|Geography}}<br />
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Category:Climate change feedbacks<br />
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* {{annotated link|Biocoenosis}}<br />
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Category:Biogeochemistry<br />
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类别: 气象假说<br />
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<small>This page was moved from [[wikipedia:en:Gaia hypothesis]]. Its edit history can be viewed at [[盖亚假说/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%9B%96%E4%BA%9A%E5%81%87%E8%AF%B4&diff=18462盖亚假说2020-11-16T09:05:58Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Hypothesis that living organisms interact with their surroundings in a self-regulating system}}<br />
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[[File:The Earth seen from Apollo 17.jpg|thumb|The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth]]'s conditions, as the Earth is the only planet currently known to harbour life (''[[The Blue Marble]]'', 1972 [[Apollo 17]] photograph)]]<br />
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The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth's conditions, as the Earth is the only planet currently known to harbour life (The Blue Marble, 1972 Apollo 17 photograph)]]<br />
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行星可居住性的研究部分基于对[[地球条件]的了解推断,因为地球是目前已知的唯一一颗拥有生命的行星 <br />
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The '''Gaia hypothesis''' {{IPAc-en|ˈ|ɡ|aɪ|.|ə}}, also known as the '''Gaia theory''' or the '''Gaia principle''', proposes that living [[organism]]s interact with their [[Inorganic compound|inorganic]] surroundings on [[Earth]] to form a [[Synergy|synergistic]] and [[Homeostasis|self-regulating]], [[complex system]] that helps to maintain and perpetuate the conditions for [[life]] on the planet.<br />
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The Gaia hypothesis , also known as the Gaia theory or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet.<br />
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盖亚假说(又称盖亚理论或盖亚原理)提出,生物体与地球上的无机环境相互作用,形成一个协同和自我调节的复杂系统,有助于维持和延续地球上的生命条件。<br />
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The hypothesis was formulated by the chemist [[James Lovelock]]<ref name="J1972" /> and co-developed by the microbiologist [[Lynn Margulis]] in the 1970s.<ref name="lovelock1974">{{cite journal|last1=Lovelock|first1=J.E.|last2=Margulis|first2=L.|title=Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis|journal=Tellus|date=1974|volume=26|series=Series A|issue=1–2|pages=2–10|doi=10.1111/j.2153-3490.1974.tb01946.x|publisher=International Meteorological Institute|location=Stockholm|issn=1600-0870|ref=harv|bibcode=1974Tell...26....2L}}</ref> Lovelock named the idea after [[Gaia]], the primordial goddess who personified the Earth in [[Greek mythology]]. In 2006, the [[Geological Society of London]] awarded Lovelock the [[Wollaston Medal]] in part for his work on the Gaia hypothesis.<ref>{{cite web|title=Wollaston Award Lovelock|url=https://www.geolsoc.org.uk/About/History/Awards-Citations-Replies-2001-Onwards/2006-Awards-Citations-Replies|accessdate=19 October 2015}}</ref><br />
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The hypothesis was formulated by the chemist James Lovelock Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis.<br />
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这个假设是由化学家詹姆斯 洛夫洛克提出的,他以希腊神话中地球的化身盖亚的名字命名了这个想法。2006年,伦敦地质学会授予洛夫洛克沃拉斯顿勋章,部分原因是他在<font color="#ff8000"> 盖亚假说Gaia hypothesis</font>方面的工作。 <br />
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Topics related to the hypothesis include how the [[biosphere]] and the [[evolution]] of organisms affect the stability of [[global temperature]], [[salinity]] of [[seawater]], [[atmospheric oxygen]] levels, the maintenance of a [[hydrosphere]] of liquid water and other environmental variables that affect the [[habitability of Earth]].<br />
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Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth.<br />
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与该假设有关的主题包括生物圈和生物体的进化如何影响全球温度的稳定性、海水的盐度、大气中的氧含量、液态水的水圈的维持以及其他影响地球宜居性的环境变量。<br />
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The Gaia hypothesis was initially criticized for being [[teleological]] and against the principles of [[natural selection]], but later refinements aligned the Gaia hypothesis with ideas from fields such as [[Earth system science]], [[biogeochemistry]] and [[systems ecology]].<ref name="Turney, Jon 2003"/><ref name="Schwartzman2002">{{cite book |author=Schwartzman, David |title=Life, Temperature, and the Earth: The Self-Organizing Biosphere |publisher=Columbia University Press |date=2002 |isbn=978-0-231-10213-1 }}</ref><ref>Gribbin, John (1990), "Hothouse earth: The greenhouse effect and Gaia" (Weidenfeld & Nicolson)</ref> Lovelock also once described the "geophysiology" of the Earth.<ref name="agesofgaia">Lovelock, James, (1995) "The Ages of Gaia: A Biography of Our Living Earth" (W.W.Norton & Co)</ref>{{Explain|date=December 2017}} Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<ref name="kirchner2002">{{Citation |last= Kirchner |first = James W. |title =Toward a future for Gaia theory |journal=[[Climatic Change (journal)|Climatic Change]] |volume = 52 |issue = 4 |pages = 391–408 |date = 2002 | doi = 10.1023/a:1014237331082 }}</ref><ref name="volk2002">{{Citation |last= Volk |first = Tyler |title =The Gaia hypothesis: fact, theory, and wishful thinking |journal = Climatic Change |volume = 52 |issue = 4 |pages = 423–430 |date = 2002 | doi = 10.1023/a:1014218227825 }}</ref><ref name="beerling2007">{{cite book |last=Beerling |first=David |authorlink=David Beerling|date=2007 |title=The Emerald Planet: How plants changed Earth's history |url=http://ukcatalogue.oup.com/product/9780192806024.do |location=Oxford|publisher=Oxford University Press |page= |isbn= 978-0-19-280602-4 |accessdate= }}</ref><br />
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The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Lovelock also once described the "geophysiology" of the Earth. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<br />
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盖亚假说最初被批评为目的论和反对自然选择的原则,但后来的改进使盖亚假说与来自地球系统科学、生物地球化学和系统生态学等领域的想法相一致。洛夫洛克还曾经描述过地球的“地球物理学”。即便如此,盖亚假说仍然受到批评,今天许多科学家认为它只有微弱的支持,或与现有的证据相矛盾。<br />
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==Overview总览==<br />
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Gaian hypotheses suggest that organisms [[Co-evolution|co-evolve]] with their environment: that is, they "influence their [[abiotic]] environment, and that environment in turn influences the [[Biota (ecology)|biota]] by [[Darwinism|Darwinian process]]". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early [[Bacteria|thermo-acido-philic]] and [[methanogenic bacteria]] towards the oxygen-enriched [[atmosphere]] today that supports more [[Phanerozoic|complex life]].<br />
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Gaian hypotheses suggest that organisms co-evolve with their environment: that is, they "influence their abiotic environment, and that environment in turn influences the biota by Darwinian process". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early thermo-acido-philic and methanogenic bacteria towards the oxygen-enriched atmosphere today that supports more complex life.<br />
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盖恩假说认为,生物体与其环境共同进化:也就是说,它们“影响它们的非生物环境,而环境反过来又通过达尔文的过程影响生物群”。Lovelock(1995)在他的第二本书中提供了证据,展示了从早期嗜酸和产甲烷细菌的世界向今天支持更复杂生命的富氧大气的进化。<br />
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A reduced version of the hypothesis has been called "influential Gaia"<ref name=":02">{{Cite journal|last=Lapenis|first=Andrei G.|year=2002|title=Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?|url=|journal=The Professional Geographer|volume=54 |issue=3|pages=379–391|via=[Peer Reviewed Journal]|doi=10.1111/0033-0124.00337}}</ref> in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the [[Biota (ecology)|biota]] influence certain aspects of the abiotic world, e.g. [[temperature]] and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<ref name=":02" /> and biogeochemical processes. An example is how the activity of [[Photosynthesis|photosynthetic]] bacteria during Precambrian times completely modified the [[Earth's atmosphere|Earth atmosphere]] to turn it aerobic, and thus supports the evolution of life (in particular [[eukaryotic]] life).<br />
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A reduced version of the hypothesis has been called "influential Gaia" in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the biota influence certain aspects of the abiotic world, e.g. temperature and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<br />
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在《生物圈的定向进化: 生物地球化学选择还是盖亚? 》一书中,这一假说的简化版被称为“有影响力的盖亚”由安德烈·G·拉佩尼斯所著,他指出生物群影响着非生物世界的某些方面,例如:温度和大气。这不是一个人的工作,而是一个俄罗斯科学研究的集体,合并成这个同行评议的出版物。它通过“微观力量”阐述了生命与环境的共同进化<br />
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Since barriers existed throughout the twentieth century between Russia and the rest of the world, it is only relatively recently that the early Russian scientists who introduced concepts overlapping the Gaia hypothesis have become better known to the Western scientific community.<ref name=":02" /> These scientists include [[Piotr Kropotkin|Piotr Alekseevich Kropotkin]] (1842–1921) (although he spent much of his professional life outside Russia), Vasil’evich Rizpolozhensky (1847–1918), [[Vladimir Ivanovich Vernadsky]] (1863–1945), and Vladimir Alexandrovich Kostitzin (1886–1963).<br />
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由于二十世纪俄罗斯与世界其他地区之间存在着隔阂,直到最近,引进了盖亚假说重叠概念的早期俄罗斯科学家才为西方科学界所熟知 <br />
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The Gaia hypothesis posits that the Earth is a self-regulating complex system involving the biosphere, the atmosphere, the hydrospheres and the pedosphere, tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<br />
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盖亚假说认为,地球是一个自我调节的复杂系统,包括生物圈、大气层、水圈和土壤圈,作为一个进化的系统紧密结合在一起。这个假说认为,这个被称为盖亚的系统作为一个整体,寻求一个适合当代生命的物理和化学环境。<br />
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Biologists and Earth scientists usually view the factors that stabilize the characteristics of a period as an undirected [[emergent property]] or [[entelechy]] of the system; as each individual species pursues its own self-interest, for example, their combined actiYons may have counterbalancing effects on environmental change. Opponents of this view sometimes reference examples of events that resulted in dramatic change rather than stable equilibrium, such as the conversion of the Earth's atmosphere from a [[reducing environment]] to an [[oxygen]]-rich one at the end of the [[Archean|Archaean]] and the beginning of the [[Proterozoic]] periods.<br />
生物学家和地球科学家通常将稳定一个时期特征的因素视为系统的一个无方向的[[涌现属性]]或[[有目的行为]];例如,由于每个物种都追求自身利益,它们的联合行动可能对环境变化产生抵消作用。反对这一观点的人有时会举出一些事件的例子,这些事件导致了巨大的变化,而不是稳定的平衡,例如在[[太古宙|太古代]]末期和[[元古代]]时期开始时,地球大气从[[还原环境]]转变为富含[[氧气]]。 <br />
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Gaia evolves through a cybernetic feedback system operated unconsciously by the biota, leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially microorganisms, with inorganic elements. These processes establish a global control system that regulates Earth's surface temperature, atmosphere composition and ocean salinity, powered by the global thermodynamic disequilibrium state of the Earth system.<!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
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盖亚通过一个由生物群无意识操作的控制论反馈系统进化,在一个完全的内稳态中达成可居住条件的广泛稳定。地球表面的许多过程对生命的条件至关重要,这些过程依赖于生命形式,特别是微生物与无机元素的相互作用。这些过程建立了一个全球控制系统,由地球系统的全球热力学不平衡状态提供动力,调节地球表面温度、大气成分和海洋盐度。<br />
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Less accepted versions of the hypothesis claim that changes in the biosphere are brought about through the [[Superorganism|coordination of living organisms]] and maintain those conditions through [[homeostasis]]. In some versions of [[Gaia philosophy]], all lifeforms are considered part of one single living planetary being called ''Gaia''. In this view, the atmosphere, the seas and the terrestrial crust would be results of interventions carried out by Gaia through the [[Coevolution|coevolving]] diversity of living organisms.<br />
不太被接受的假说声称生物圈的变化是通过[[超级有机体|生物体的协调]]来实现的,并通过[[内稳态]]来维持这些条件。在一些版本的[[盖亚哲学]]中,所有的生命形式都被认为是一个被称为“盖亚”的生命行星的一部分。在这种观点下,大气、海洋和地壳将是盖亚通过生物多样性进行干预的结果。 <br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of biogeochemistry, and it is being investigated also in other fields like Earth system science. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<br />
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以前在生物地球化学领域已经观察到受生命形式影响的行星内稳态的存在,而且在地球系统科学等其他领域也在研究这一现象。盖亚假说的原创性依赖于这样一种评估: 即使地球或外部事件威胁到这种平衡,这种平衡也是为了保持生命的最佳状态而积极追求的。<br />
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The Gaia hypothesis was an influence on the [[deep ecology]] movement.<ref>David Landis Barnhill, Roger S. Gottlieb (eds.), ''Deep Ecology and World Religions: New Essays on Sacred Ground'', SUNY Press, 2010, p. 32.</ref><br />
盖亚假说对[[深层生态学]]运动产生了影响 <br />
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==Details细节==<br />
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Rob Rohde's palaeotemperature graphs<br />
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罗布·罗德的古温度图<br />
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The Gaia hypothesis posits that the Earth is a self-regulating [[complex system]] involving the [[biosphere]], the [[Earth's atmosphere|atmosphere]], the [[hydrosphere]]s and the [[pedosphere]], tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<ref name="vanishing255">Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 255. {{ISBN|978-0-465-01549-8}}</ref><br />
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盖亚假说假设地球是一个自我调节的[[复杂系统]],包括[[生物圈]]、[[地球大气|大气]]、[[水圈]]和[[土壤圈]],作为一个进化系统紧密耦合。该假说认为,这个系统作为一个整体,称为盖亚,寻求一个最适合当代生活的物理和化学环境 <br />
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Since life started on Earth, the energy provided by the Sun has increased by 25% to 30%; however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on Titan. research has suggested that "oxygen shocks" and reduced methane levels led, during the Huronian, Sturtian and Marinoan/Varanger Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre Phanerozoic biosphere to fully self-regulate.<br />
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自从地球上有生命以来,太阳提供的能量增加了25%到30%;然而,地球表面温度一直保持在适宜居住的水平上,达到了相当规律的高低边缘。洛夫洛克还假设,产甲烷菌在早期大气中产生了较高水平的甲烷,这与在石化烟雾中发现的观点相似,在某些方面与土卫六上的大气相似。研究表明,在休伦期、斯图尔特期和马里诺/瓦朗格冰期,“氧冲击”和甲烷含量降低导致世界几乎变成了一个坚实的“雪球”。这些时代是前显生宙生物圈完全自我调节能力的证据。<br />
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Gaia evolves through a [[Cybernetic#In biology|cybernetic]] [[feedback]] system operated unconsciously by the [[biota (ecology)|biota]], leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially [[microorganisms]], with inorganic elements. These processes establish a global control system that regulates Earth's [[Sea surface temperature|surface temperature]], [[atmosphere composition]] and [[ocean]] [[salinity]], powered by the global thermodynamic disequilibrium state of the Earth system.<ref>Kleidon, Axel. ''How does the earth system generate and maintain thermodynamic disequilibrium and what does it imply for the future of the planet?''. Article submitted to the ''Philosophical Transactions of the Royal Society'' on Thu, 10 Mar 2011</ref><!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
盖亚通过一个[[控制论|生物学|控制论]][[反馈]]系统在[[生物群(生态学)|生物群]]的无意识运作中进化,导致在完全的内稳态中可居住条件的广泛稳定。地球表面对生命条件至关重要的许多过程都依赖于生物,特别是[微生物]与无机元素的相互作用。这些过程建立了一个全球控制系统,调节地球的[[海表温度|表面温度]]、[[大气组成]]和[[海洋]][[盐度]],其动力来自地球系统的全球热力学不平衡状态。<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
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说明了处理温室气体CO2在维持地球温度在可居住范围内起着关键作用。<br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of [[biogeochemistry]], and it is being investigated also in other fields like [[Earth system science]]. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 179. {{ISBN|978-0-465-01549-8}}</ref><br />
受生命形式影响的行星内稳态的存在,以前在[[生物地球化学]]领域就已被观察到,而且在其他领域,如[[地球系统科学]]也在研究中。盖亚假说的独创性依赖于这样一种评估,即积极追求这种体内平衡,以保持生命的最佳状态,即使是在地球或外部事件威胁它们的时候。<br />
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The CLAW hypothesis, inspired by the Gaia hypothesis, proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative feedback loop that acts to stabilise the temperature of the Earth's atmosphere.<br />
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受盖亚假说的启发,CLAW 假说提出了一个在海洋生态系统和地球气候之间运行的反馈回路。该假说特别提出,产生二甲硫醚的浮游植物对气候强迫的变化有反应,这些反应导致了一个负反馈循环,稳定了地球大气的温度。<br />
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===Regulation of global surface temperature地球表面温度的调控===<br />
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[[File:All palaeotemps.png|thumb|480px|Rob Rohde's palaeotemperature graphs]]<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of greenhouse gases may cause negative feedbacks in the environment to become positive feedback. Lovelock has stated that this could bring an extremely accelerated global warming, but he has since stated the effects will likely occur more slowly.<br />
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目前,人口的增加及其活动对环境的影响,例如温室气体的增加,可能导致环境中的负反馈成为正反馈。洛夫洛克表示,这可能会极大地加速全球变暖,但他后来又表示,这种影响可能会发生得更慢。<br />
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{{See also|Paleoclimatology}}<br />
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Since life started on Earth, the energy provided by the [[Sun]] has increased by 25% to 30%;<ref name="Owen1979">{{cite journal | author = Owen, T. | author2 = Cess, R.D. | author3 = Ramanathan, V. | date = 1979 | title = Earth: An enhanced carbon dioxide greenhouse to compensate for reduced solar luminosity | journal = [[Nature (journal)|Nature]] | volume = 277 | pages = 640–2 | doi = 10.1038/277640a0 | issue=5698 | bibcode = 1979Natur.277..640O | ref = harv }}</ref> however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on [[Titan (moon)|Titan]].<ref name="agesofgaia"/> This, he suggests tended to screen out ultraviolet until the formation of the ozone screen, maintaining a degree of homeostasis. However, the [[Snowball Earth]]<ref>Hoffman, P.F. 2001. [http://www.snowballearth.org ''Snowball Earth theory'']</ref> research has suggested that "oxygen shocks" and reduced methane levels led, during the [[Huronian]], [[Sturtian]] and [[Marinoan]]/[[Cryogenian|Varanger]] Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre [[Phanerozoic]] biosphere to fully self-regulate.<br />
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Plots from a standard black and white [[Daisyworld simulation]]<br />
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从一个标准的黑白图[[雏菊世界模拟]]<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
说明了在温室气体维持低于临界温度的过程中,CO2起着至关重要的作用。 <br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic group selection and cooperation between organisms, James Lovelock and Andrew Watson developed a mathematical model, Daisyworld, in which ecological competition underpinned planetary temperature regulation.<br />
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有人批评盖亚假说似乎需要不切实际的群体选择和有机体之间的合作,为了回应这种批评,James Lovelock 和 Andrew Watson建立了一个数学模型---- 雏菊世界,其中生态竞争支撑着地。<br />
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The [[CLAW hypothesis]], inspired by the Gaia hypothesis, proposes a [[feedback|feedback loop]] that operates between [[ocean]] [[ecosystem]]s and the [[Earth]]'s [[climate]].<ref name="CLAW87">{{cite journal |doi=10.1038/326655a0 |author=[[Robert Jay Charlson|Charlson, R. J.]], [[James Lovelock|Lovelock, J. E]], Andreae, M. O. and Warren, S. G. |title=Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate |journal=Nature |volume=326 |issue=6114 |pages=655–661 |date=1987 |bibcode=1987Natur.326..655C |ref=harv }}</ref> The [[hypothesis]] specifically proposes that particular [[phytoplankton]] that produce [[dimethyl sulfide]] are responsive to variations in [[climate forcing]], and that these responses lead to a [[negative feedback|negative feedback loop]] that acts to stabilise the [[temperature]] of the [[Earth's atmosphere]].<br />
受到盖亚假说启发的[[爪假说]]提出了一个在[[海洋]][[生态系统]]和[[地球]]的[[气候]]之间运行的[[反馈|反馈回路]]。<br />
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Daisyworld examines the energy budget of a planet populated by two different types of plants, black daisies and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the albedo of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
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《雏菊世界》调查了一个星球的能量预算,这个星球上生长着两种不同的植物,黑色雏菊和白色雏菊,这两种植物被认为占据了星球表面的很大一部分。雏菊的颜色影响了地球的反照率,黑色的雏菊吸收更多的光线,使地球变暖,而白色的雏菊则反射更多的光线,使地球变冷。人们认为黑色雏菊在较低的温度下生长和繁殖最好,而白色雏菊则被认为在较高的温度下生长最好。当温度上升到接近白色雏菊所喜欢的温度时,白色雏菊伸展出黑色雏菊,导致更大比例的白色表面,更多的阳光被反射,减少热量输入,最终使地球降温。相反,随着气温的下降,黑色雏菊长出了白色雏菊,吸收了更多的阳光,使地球变暖。因此,温度会收敛到与植物繁殖率相等的值。<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of [[greenhouse gases]] may cause [[negative feedback]]s in the environment to become [[positive feedback]]. Lovelock has stated that this could bring an [[James Lovelock#The revenge of Gaia|extremely accelerated global warming]],<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, {{ISBN|978-0-465-01549-8}}</ref> but he has since stated the effects will likely occur more slowly.<ref>Lovelock J., NBC News. [http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite Link] Published 23 April 2012, accessed 22 August 2012. {{Webarchive|url=https://web.archive.org/web/20120913163635/http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite |date=13 September 2012 }}</ref><br />
目前,人口的增加及其活动对环境的影响,如[[温室气体]]的倍增,可能导致环境中的[[负反馈]]变成[[正反馈]]。洛夫洛克曾表示,这可能会带来一场【【James Loveloc【《盖亚的复仇』极度加速的全球变暖】】 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this negative feedback due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
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洛夫洛克和沃森指出,在有限的条件下,如果太阳的能量输出发生变化,由于竞争而产生的负反馈可以将地球温度稳定在支持生命的数值上,而没有生命的地球则会表现出巨大的温度波动。白色和黑色雏菊的百分比会不断变化,以保持植物繁殖率相等的温度值,使两种生命形式都能茁壮成长。<br />
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====Daisyworld simulations雏菊世界模拟====<br />
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[[File:StandardDaisyWorldRun2color.gif|thumb|280px|Plots from a standard black and white [[Daisyworld]] simulation]]<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<br />
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有人认为,这些结果是可以预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的答案。<br />
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{{Main|Daisyworld}}<br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic [[group selection]] and [[Cooperation (evolution)|cooperation]] between organisms, James Lovelock and [[Andrew Watson (scientist)|Andrew Watson]] developed a mathematical model, [[Daisyworld]], in which [[Competition (biology)|ecological competition]] underpinned planetary temperature regulation.<ref name="daisyworld">{{cite journal<br />
有人批评盖亚假说似乎需要有机体之间不切实际的[[群体选择]]和[[合作(进化)|合作]],詹姆斯·洛夫洛克和[[安德鲁·沃森(科学家)|安德鲁·沃森]]开发了一个数学模型,[[雏菊世界]],其中[[竞争(生物学)|生态竞争]]为基础行星温度调节。 <br />
|date = 1983<br />
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Ocean salinity has been constant at about 3.5% for a very long time. Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested that salinity may also be strongly influenced by seawater circulation through hot basaltic rocks, and emerging as hot water vents on mid-ocean ridges. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<br />
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长期以来,海洋盐度一直保持在3.5% 左右。海洋环境中盐度的稳定性很重要,因为大多数细胞需要相当恒定的盐度,一般不能容忍超过5% 的盐度值。恒定的海洋盐度是一个长期存在的秘密,因为没有任何方法可以抵消来自河流的盐的流入。最近有人提出,盐度也可能受到穿过炽热玄武岩的海水循环的强烈影响,并在洋中脊上出现热水喷口。然而,海水的组成离平衡还很远,如果没有有机过程的影响,很难解释这一事实。有一种解释认为,地球历史上盐原的形成是原因之一。据推测,这些是由细菌菌落产生的,它们在生命过程中固定离子和重金属。<br />
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|title = Biological homeostasis of the global environment: the parable of Daisyworld<br />
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|journal = Tellus<br />
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|volume = 35B<br />
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Vostok, Antarctica research station. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
沃斯托克,南极洲研究站。当前期间在左边。<!--基于此图表的GIMP-FX版本的非源材料。现在的版本是正确的,原版的。必须删除这句话:请注意,当前CO2水平超过390ppm,远高于过去40万年来的任何时候-->] <br />
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|pages = 286–9<br />
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|bibcode = 1983TellB..35..284W<br />
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|doi = 10.1111/j.1600-0889.1983.tb00031.x<br />
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The Gaia hypothesis states that the Earth's atmospheric composition is kept at a dynamically steady state by the presence of life. The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than noble gases present in the atmosphere are either made by organisms or processed by them.<br />
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盖亚假说认为,地球的大气组成是由于生命的存在而保持在动态稳定的状态。大气成分提供了现代生活已经适应的条件。大气中除惰性气体以外的所有大气气体,要么是由生物体产生的,要么是由生物体加工的。<br />
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|last1 = Watson | first1= A.J. | last2= Lovelock | first2= J.E<br />
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The stability of the atmosphere in Earth is not a consequence of chemical equilibrium. Oxygen is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the Great Oxygenation Event. Since the start of the Cambrian period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume. Traces of methane (at an amount of 100,000 tonnes produced per year) should not exist, as methane is combustible in an oxygen atmosphere.<br />
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地球大气层的稳定性不是化学平衡的结果。氧是一种活性化合物,最终会与地球大气层和地壳中的气体和矿物质结合。在大氧化事件空间站开始之前,大约5000万年左右,氧气才开始在大气中少量地持续存在。自寒武纪以来,大气中氧浓度一直在大气体积的15% 至35% 之间波动。微量的甲烷(每年产生100,000吨)不应该存在,因为甲烷在氧气氛中是可燃的。<br />
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|ref = harv<br />
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Dry air in the atmosphere of Earth contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases including methane. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. <br />
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地球大气层中的干燥空气大致(按体积计算)含有78.09% 的氮气、20.95% 的氧气、0.93% 的氩气、0.039% 的二氧化碳以及少量的其他气体,包括甲烷。洛夫洛克最初推测,高于25% 的氧气浓度会增加森林大火和森林大火的发生频率。最近在石炭纪和白垩纪煤系地质时期,当O2确实超过了25%时,火成木炭的研究结果支持了 Lovelock 的论点。<br />
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Daisyworld examines the [[Earth's energy budget|energy budget]] of a [[planet]] populated by two different types of plants, black [[Asteraceae|daisies]] and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the [[albedo]] of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
Daisyworld研究了[[地球的能源预算|能源预算]]的[[地球的能源预算]]居住着两种不同类型的植物,黑色的[[菊科的雏菊]]和白色的雏菊,这两种植物被认为占据了地表的很大一部分。雏菊的颜色影响着这个星球的[反照率],因此黑色雏菊吸收更多的光并温暖地球,而白色雏菊则反射更多的光并使地球降温。黑雏菊在较低温度下生长繁殖最好,而白雏菊在较高温度下生长繁殖最好。当温度上升到接近白色雏菊的数值时,白色雏菊的繁殖能力超过了黑色雏菊,导致白色表面的比例增大,更多的阳光被反射,减少了热量输入,最终使地球变冷。相反,随着温度的下降,黑雏菊的繁殖能力超过了白雏菊,吸收了更多的阳光,使地球变暖。因此,温度将收敛到植物繁殖率相等的值。 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this [[negative feedback]] due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
Lovelock和Watson表明,在有限的条件范围内,如果太阳的能量输出发生变化,由于竞争而产生的[[负面反馈]]可以将地球的温度稳定在支持生命的值上,而没有生命的行星则会出现大范围的温度波动。白雏菊和黑雏菊的比例会不断变化,以使温度保持在植物繁殖率相等的值,从而使两种生命形式都能茁壮成长。 <br />
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Gaia scientists see the participation of living organisms in the carbon cycle as one of the complex processes that maintain conditions suitable for life. The only significant natural source of atmospheric carbon dioxide (CO<sub>2</sub>) is volcanic activity, while the only significant removal is through the precipitation of carbonate rocks. Carbon precipitation, solution and fixation are influenced by the bacteria and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
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盖亚的科学家们把生物体参与碳循环看作是维持适合生命条件的复杂过程之一。火山活动是大气中二氧化碳的唯一重要自然来源,而碳酸盐岩的沉淀是大气中二氧化碳唯一重要的去除途径。碳沉淀、溶解和固定受到土壤中细菌和植物根系的影响,这些细菌和植物根系可以改善气体循环,或者在珊瑚礁中,碳酸钙以固体的形式沉积在海底。碳酸钙被活的有机体用来制造含碳的试验和外壳。一旦死亡,生物体的外壳就会沉到海底,在那里它们产生白垩和石灰石的沉淀物。<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<ref>{{cite journal | doi = 10.1023/A:1023494111532 | date = 2003 | last1 = Kirchner | first1 = James W. | journal = Climatic Change | volume = 58 |issue=1–2| pages = 21–45 |title=The Gaia Hypothesis: Conjectures and Refutations | ref = harv}}</ref><br />
有人认为,结果是可预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的反应。 <br />
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One of these organisms is Emiliania huxleyi, an abundant coccolithophore algae which also has a role in the formation of clouds. CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants. Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean algal blooms are also increasing.<br />
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其中一种是赫氏圆石藻,这是一种数量丰富的颗石藻类,也参与了云的形成。CO < sub > 2 </sub > 过量通过增加球石氟化物的寿命来补偿,增加了锁定在海底的 CO < sub > 2 </sub > 的数量。球石粉会增加云量,从而控制地表温度,有助于降低整个地球的温度,有利于地球上植物所必需的降水。近年来,大气中 CO < < sub > 2 </sub > 浓度有所增加,有证据表明,海洋藻华的浓度也在增加。<br />
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===Regulation of oceanic salinity海洋盐度调节 ===<br />
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Lichen and other organisms accelerate the weathering of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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地衣和其他生物加速了岩石表面的风化,而岩石在土壤中的分解也加快了,这要归功于根、真菌、细菌和地下动物的活动。因此,二氧化碳从大气层流向土壤的过程是在生物的帮助下进行调节的。当大气中 CO2水平升高时,温度升高,植物生长。这种生长会增加植物对二氧化碳的消耗,植物会将二氧化碳处理到土壤中,从大气中排出。<br />
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Ocean [[salinity]] has been constant at about 3.5% for a very long time.<ref name=":0">{{Cite book|title=The Introduction to Ocean Sciences|last=Segar|first=Douglas|publisher=Library of Congress|year=2012|isbn=978-0-9857859-0-1|location=http://www.reefimages.com/oceans/SegarOcean3Chap05.pdf|pages=Chapter 5 3rd Edition|quote=|via=}}</ref> Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested<ref name="Gorham19912">{{cite journal|last=Gorham|first=Eville|date=1 January 1991|title=Biogeochemistry: its origins and development|journal=Biogeochemistry|publisher=Kluwer Academic|volume=13|issue=3|pages=199–239|doi=10.1007/BF00002942|issn=1573-515X|ref=harv}}</ref> that salinity may also be strongly influenced by [[seawater]] circulation through hot [[basalt]]ic rocks, and emerging as hot water vents on [[mid-ocean ridge]]s. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<ref name=":0" /><br />
在很长一段时间内,海洋盐度一直保持在3.5%左右。[23]海洋环境中的盐度稳定性非常重要,因为大多数细胞需要相当恒定的盐度,并且通常不能容忍超过5%的盐度值。恒定的海洋盐度是一个长期存在的谜团,因为没有任何过程可以抵消河流中的盐流入。最近有人认为[24]海水通过热玄武质岩石时也会受到海水循环的强烈影响,并在大洋中脊上出现热水喷口。然而,海水的组成远未达到平衡,如果没有有机过程的影响,很难解释这一事实。一个建议的解释是,在整个地球的历史中,盐平原的形成。据推测,这些细菌是由在生命过程中固定离子和重金属的菌落产生的<br />
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In the biogeochemical processes of Earth, sources and sinks are the movement of elements. The composition of salt ions within our oceans and seas is: sodium (Na<sup>+</sup>), chlorine (Cl<sup>−</sup>), sulfate (SO<sub>4</sub><sup>2−</sup>), magnesium (Mg<sup>2+</sup>), calcium (Ca<sup>2+</sup>) and potassium (K<sup>+</sup>). The elements that comprise salinity do not readily change and are a conservative property of seawater.<ref name=":0" /> There are many mechanisms that change salinity from a particulate form to a dissolved form and back. The known sources of sodium i.e. salts are when weathering, erosion, and dissolution of rocks are transported into rivers and deposited into the oceans.<br />
在地球的生物地球化学过程中,源和汇是元素的运动。我们海洋中盐离子的组成是:钠(Na+)、氯(Cl-)、硫酸盐(SO42-)、镁(Mg2+)、钙(Ca2+)和钾(K+)。构成盐度的元素不易变化,是海水的一种保守属性。[23]有许多机制可以将盐度从颗粒形态改变为溶解形态,然后再返回。已知的钠(即盐)来源于岩石的风化、侵蚀和溶解作用被输送到河流中并沉积到海洋中。 <br />
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The [[Mediterranean Sea]] as being Gaia's kidney is found ([http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/ here]) by Kenneth J. Hsue, a correspondence author in 2001. The "[[desiccation]]" of the Mediterranean is the evidence of a functioning kidney. Earlier "kidney functions" were performed during the "[[Deposition (geology)|deposition]] of the [[Cretaceous]] ([[Atlantic Ocean|South Atlantic]]), [[Jurassic]] ([[Gulf of Mexico]]), [[Permian–Triassic extinction event|Permo-Triassic]] ([[Europe]]), [[Devonian]] ([[Canada]]), [[Cambrian]]/[[Precambrian]] ([[Gondwana]]) saline giants."<ref>{{Cite web|url=http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/|title=Scientia Marina: List of Issues|last=http://www.webviva.com|first=Justino Martinez. Web Viva 2007|website=scimar.icm.csic.es|language=English|access-date=2017-02-04}}</ref><br />
地中海是盖亚的肾脏,由肯尼斯·J·休伊(KennethJ.Hsue)在2001年发现的。地中海的“干涸”是肾功能正常的证据。早期的“肾功能”是在“白垩纪(南大西洋)、侏罗纪(墨西哥湾)、二叠纪-三叠纪(欧洲)、泥盆纪(加拿大)、寒武纪/前寒武纪(冈瓦纳)盐沼沉积时期进行的。” <br />
[[Earthrise taken from Apollo 8 on December 24, 1968]]<br />
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[1968年12月24日阿波罗8号拍摄的地出]<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The mythical Gaia was the primal Greek goddess personifying the Earth, the Greek version of "Mother Nature" (from Ge = Earth, and Aia = <br />
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地球作为一个完整的整体,一个有生命的存在,这个观念有着悠久的传统。神话中的盖亚是拟人化地球的原始希腊女神,是希腊版本的“自然母亲”(来自 Ge = 地球,和 Aia = <br />
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===Regulation of oxygen in the atmosphere大气层的氧气调节===<br />
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PIE grandmother), or the Earth Mother. James Lovelock gave this name to his hypothesis after a suggestion from the novelist William Golding, who was living in the same village as Lovelock at the time (Bowerchalke, Wiltshire, UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry. Later, the naturalist and explorer Alexander von Humboldt recognized the coevolution of living organisms, climate, and Earth's crust. His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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派祖母,或地球母亲。詹姆斯·洛夫洛克根据小说家威廉·戈尔丁的建议给他的假设起了这个名字,他当时和洛夫洛克住在同一个村子里(英国威尔特郡鲍尔查尔克)。戈尔丁的建议是以Gea为基础的,Gea是希腊女神名字的另一种拼写,在地质学、地球物理和地球化学中,Gea是前缀。后来,博物学家和探险家亚历山大·冯·洪堡认识到生物、气候和地壳的共同进化。他的远见卓识的声明在西方没有被广泛接受,几十年后,盖亚假说受到了科学界同样类型的最初抵制。<br />
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[[File:Vostok 420ky 4curves insolation.jpg|thumb|280px|Levels of gases in the atmosphere in 420,000 years of ice core data from [[Vostok Station|Vostok, Antarctica research station]]. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
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{{See also|Geological history of oxygen}}<br />
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Also in the turn to the 20th century Aldo Leopold, pioneer in the development of modern environmental ethics and in the movement for wilderness conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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同样在20世纪之交,现代环境伦理学发展的先驱、荒野保护运动的先驱奥尔多 · 利奥波德在他的生物中心或整体的土地伦理学中提出了一个有生命的地球。<br />
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The Gaia hypothesis states that the Earth's [[Atmospheric chemistry#Atmospheric composition|atmospheric composition]] is kept at a dynamically steady state by the presence of life.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 163. {{ISBN|978-0-465-01549-8}}</ref> The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than [[noble gas]]es present in the atmosphere are either made by organisms or processed by them.<br />
盖亚假说指出,地球的大气成分由于生命的存在而保持在动态稳定的状态。大气中除惰性气体以外的所有大气气体都是由生物体制造或加工而成。<br />
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The stability of the atmosphere in Earth is not a consequence of [[chemical equilibrium]]. [[Oxygen]] is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the [[Great Oxygenation Event]].<ref name=Anabar2007>{{Cite journal| last4 = Arnold| last6 = Creaser| last3 = Lyons| first1 = A. | first2 = Y.| last9 = Scott| last2 = Duan | first3 = T. | first4 = G.| last8 = Gordon | first5 = B. | first10 = J. | first6 = R.| last10 = Garvin | first7 = A.| last11 = Buick | first8 = G. | first11 = R. | first9 = C.| title = A whiff of oxygen before the great oxidation event?| journal = Science| volume = 317| issue = 5846| year = 2007| last7 = Kaufman| pages = 1903–1906| last5 = Kendall| pmid = 17901330| last1 = Anbar | doi = 10.1126/science.1140325|bibcode = 2007Sci...317.1903A }}</ref> Since the start of the [[Cambrian]] period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume.<ref name=Berner1999>{{Cite journal<br />
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Another influence for the Gaia hypothesis and the environmental movement in general came as a side effect of the Space Race between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph Earthrise taken by astronaut William Anders in 1968 during the Apollo 8 mission became, through the Overview Effect an early symbol for the global ecology movement.<br />
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盖亚假说和环境运动的另一个影响来自于苏联和美利坚合众国之间太空竞赛的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球作为一个整体的样子。1968年,宇航员威廉 · 安德斯在阿波罗8号任务期间拍摄的地出照片,通过总体效应成为全球生态运动的早期象征。<br />
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| pmid = 10500106<br />
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| date=Sep 1999 | last1 = Berner | first1 = R. A.<br />
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| title = Atmospheric oxygen over Phanerozoic time<br />
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[[James Lovelock, 2005]]<br />
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[ James Lovelock,2005]<br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the Jet Propulsion Laboratory in California on methods of detecting life on Mars. The first paper to mention it was Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life, co-authored with C.E. Giffin. A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the Pic du Midi observatory, planets like Mars or Venus had atmospheres in chemical equilibrium. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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65年9月,洛夫洛克在加利福尼亚喷气推进实验室研究探测火星生命的方法时,开始定义由生物群落控制的自我调节地球的概念。第一篇提到它的论文是行星大气:与C.E.Giffin合著的与生命存在有关的成分和其他变化。一个主要的概念是,通过大气的化学成分可以在行星尺度上探测到生命。根据picdumidi天文台收集的数据,像火星或金星这样的行星,其大气层处于化学平衡状态。这种与地球大气的差异被认为是这些行星上没有生命的证据。 <br />
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Lovelock formulated the Gaia Hypothesis in journal articles in 1972 and 1974, and a popular book length version of the hypothesis, published in 1979 as The Quest for Gaia, began to attract scientific and critical attention.<br />
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洛夫洛克在1972年和1974年的期刊文章中提出了盖亚假说,并在1979年出版了一本畅销书,名为《寻找盖亚》 ,开始引起科学界和批判界的关注。<br />
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| journal = Proceedings of the National Academy of Sciences of the United States of America<br />
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Lovelock called it first the Earth feedback hypothesis, and it was a way to explain the fact that combinations of chemicals including oxygen and methane persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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洛夫洛克首先将其称为地球反馈假说,这是一种解释包括氧气和甲烷在内的化学物质在地球大气中保持稳定浓度的方法。洛夫洛克认为,在其他行星的大气层中探测这种组合,是一种相对可靠和廉价的探测生命的方法。<br />
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| doi = 10.1073/pnas.96.20.10955<br />
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[[Lynn Margulis]]<br />
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[琳 · 玛格丽丝]<br />
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|bibcode = 1999PNAS...9610955B }}</ref> Traces of [[Atmospheric methane|methane]] (at an amount of 100,000 tonnes produced per year)<ref name="Cicerone1988">{{cite journal |last1=Cicerone |first1=R.J. |last2=Oremland |first2=R.S. |date=1988 |title=Biogeochemical aspects of atmospheric methane |journal=Global Biogeochemical Cycles |volume=2 |issue=4 |pages=299–327 |url=//webfiles.uci.edu/setrumbo/public/Methane_papers/Cicerone_Global%20Biogeochem%20Cy_1988.pdf |doi=10.1029/GB002i004p00299 |bibcode=1988GBioC...2..299C}}</ref> should not exist, as methane is combustible in an oxygen atmosphere.<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<br />
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后来出现了其他关系,例如海洋生物产生的硫和碘的数量与陆地生物所需的数量大致相同,这些都支持了这一假说。<br />
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Dry air in the [[atmosphere of Earth]] contains roughly (by volume) 78.09% [[nitrogen]], 20.95% oxygen, 0.93% [[argon]], 0.039% [[Carbon dioxide in the Earth's atmosphere|carbon dioxide]], and small amounts of other gases including [[methane]]. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. {{citation needed|date=June 2012}}<br />
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[[地球大气]]中的干空气大约(按体积)包含78.09%[[氮]],20.95%的氧,0.93%[[氩]],0.039%[地球大气中的二氧化碳|二氧化碳]],以及少量其他气体,包括[[甲烷]]。洛夫洛克最初推测,氧气浓度超过25%会增加森林火灾和火灾的发生率。最近在石炭纪和白垩纪煤系中发现的由火引起的木炭的研究,在地质时期O<sub>2</sub>超过25%,支持了Lovelock的观点 <br />
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In 1971 microbiologist Dr. Lynn Margulis joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet. The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of eukaryotic organelles and her contributions to the endosymbiotic theory, nowadays accepted. Margulis dedicated the last of eight chapters in her book, The Symbiotic Planet, to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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1971年,微生物学家 Lynn Margulis 博士加入了 Lovelock 的行列,努力将最初的假设充实为科学证明的概念,贡献了她关于微生物如何影响大气层和地球表面不同层次的知识。这位美国生物学家也唤醒了科学界的批评,因为她倡导真核细胞器起源的理论,以及她对美国共生发源学会的贡献,现在被接受了。玛格丽丝在她的书《共生星球》中将最后八章献给了盖亚。然而,她反对对盖亚的广泛拟人化,并强调盖亚“不是一个有机体” ,而是“有机体之间相互作用的一个新兴属性”。她将盖亚定义为“组成地球表面一个巨大生态系统的一系列相互作用的生态系统”。句号”。这本书最令人难忘的“口号”实际上是由马古利斯的一个学生打趣说的: “从太空看,盖亚只是共生而已。”。<br />
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===Processing of CO<sub>2</sub>二氧化碳处理===<br />
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{{See also|Carbon cycle}}<br />
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James Lovelock called his first proposal the Gaia hypothesis but has also used the term Gaia theory. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments and provided a number of useful predictions. In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating. The principal sponsor was the National Audubon Society. Speakers included James Lovelock, George Wald, Mary Catherine Bateson, Lewis Thomas, John Todd, Donald Michael, Christopher Bird, Thomas Berry, David Abram, Michael Cohen, and William Fields. Some 500 people attended.<br />
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詹姆斯 · 洛夫洛克称他的第一个提议为盖亚假说,但也使用了盖亚理论这个术语。洛夫洛克说,最初的提法是基于观察,但仍然缺乏科学的解释。盖亚假说从那以后得到了一些科学实验的支持,并提供了一些有用的预测。事实上,更广泛的研究证明了最初的假设是错误的,在这个意义上,不是生命本身,而是整个地球系统在调节。主要赞助者是奥杜邦学会。讲者包括 James Lovelock、 George Wald、 Mary Catherine Bateson、 Lewis Thomas、 John Todd、 Donald Michael、 Christopher Bird、 Thomas Berry、 David Abram、 Michael Cohen 和 William Fields。大约有500人参加。<br />
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Gaia scientists see the participation of living organisms in the [[carbon cycle]] as one of the complex processes that maintain conditions suitable for life. The only significant natural source of [[Carbon dioxide in Earth's atmosphere|atmospheric carbon dioxide]] ([[Carbon dioxide|CO<sub>2</sub>]]) is [[volcanic activity]], while the only significant removal is through the precipitation of [[carbonate rocks]].<ref name="Karhu1996">{{cite journal | author = Karhu, J.A. | author2 = Holland, H.D. | date = 1 October 1996 | title = Carbon isotopes and the rise of atmospheric oxygen | journal = [[Geology (journal)|Geology]] | volume = 24 | issue = 10 | pages = 867–870 | doi = 10.1130/0091-7613(1996)024<0867:CIATRO>2.3.CO;2|bibcode = 1996Geo....24..867K | ref = harv}}</ref> Carbon precipitation, solution and [[Carbon fixation|fixation]] are influenced by the [[bacteria]] and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
盖亚的科学家认为,生物参与[[碳循环]是维持适宜生命条件的复杂过程之一。[[地球大气中的二氧化碳|大气二氧化碳]]([[二氧化碳| CO2]])的唯一重要自然来源是[[火山活动]],而唯一显著的清除是通过[[碳酸盐岩]]的沉淀,溶液和[[固碳|固碳]]受土壤中的[[细菌]]和植物根的影响,它们改善了气体循环,珊瑚礁中碳酸钙以固体形式沉积在海底。碳酸钙被生物用来制造含碳测试和贝壳。一旦死亡,这些生物的壳就会落到海底,在那里它们会产生白垩和石灰岩的沉积物。 <br />
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One of these organisms is ''[[Emiliania huxleyi]]'', an abundant [[coccolithophore]] [[algae]] which also has a role in the formation of [[cloud]]s.<ref name="Harding2006">{{cite book |author=Harding, Stephan |title=Animate Earth |publisher=Chelsea Green Publishing |date=2006 |pages=65 |isbn=978-1-933392-29-5 }}</ref> CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants.{{citation needed|date=July 2015}} Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean [[algal bloom]]s are also increasing.<ref>{{Cite web | date = 12 September 2007 | title = Interagency Report Says Harmful Algal Blooms Increasing | url = http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | url-status = dead | archiveurl = https://web.archive.org/web/20080209234239/http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | archivedate = 9 February 2008 }}</ref><br />
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In 1988, climatologist Stephen Schneider organised a conference of the American Geophysical Union. The first Chapman Conference on Gaia,<br />
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在1988年,气候学家史蒂芬·史奈德组织了一次美国美国地球物理联盟协会的会议。关于盖亚的第一次查普曼会议,<br />
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[[Lichen]] and other organisms accelerate the [[weathering]] of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the Daisyworld Model (and its modifications, above) as evidence against most of these criticisms.<br />
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然而,洛夫洛克和其他支持盖亚理论的科学家确实试图反驳这样一种说法,即这种假设不科学,因为不可能通过控制实验来检验它。例如,针对盖亚是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修正,上文)作为反驳大多数这些批评的证据。<br />
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==History历史==<br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of teleologism ceased, following this conference.<br />
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洛夫洛克谨慎地提出了盖亚假说的一个版本,该假说没有声称盖亚有意或有意地在她的环境中维持生命赖以生存的复杂平衡。看起来,盖亚“故意”行为的说法只是他那本广受欢迎的书中的一个比喻性陈述,并不是字面意义上的理解。这种对盖亚假说的新陈述更能为科学界所接受。在这次会议之后,大多数关于目的论的指责都停止了。<br />
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===Precedents先例===<br />
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[[File:NASA-Apollo8-Dec24-Earthrise.jpg|thumb|''[[Earthrise]]'' taken from [[Apollo 8]] on December 24, 1968]]<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000, the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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到2000年6月23日在西班牙巴伦西亚举行关于盖亚假说的第二次查普曼会议时,情况发生了重大变化。与其讨论盖亚的目的论观点,或盖亚假说的“类型” ,不如将重点放在具体的机制上,通过这些机制,基本的短期内稳态在一个重要的进化的长期结构变化的框架内得以维持。<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The [[Gaia (mythology)|mythical Gaia]] was the primal Greek goddess personifying the [[Earth]], the Greek version of "[[Mother Nature]]" (from Ge = Earth, and Aia = <br />
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[[PIE]] grandmother), or the [[Earth Mother]]. James Lovelock gave this name to his hypothesis after a suggestion from the novelist [[William Golding]], who was living in the same village as Lovelock at the time ([[Bowerchalke]], [[Wiltshire]], UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry.<ref name=vanish09 /> Golding later made reference to Gaia in his [[Nobel prize]] acceptance speech.<br />
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The major questions were:<br />
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主要的问题是:<br />
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In the eighteenth century, as [[geology]] consolidated as a modern science, [[James Hutton]] maintained that geological and biological processes are interlinked.<ref name=CapraWeb>{{cite book |author=Capra, Fritjof |title=The web of life: a new scientific understanding of living systems |publisher=Anchor Books |location=Garden City, N.Y |date=1996 |page=[https://archive.org/details/weboflifenewscie00capr/page/23 23] |isbn=978-0-385-47675-1 |url=https://archive.org/details/weboflifenewscie00capr/page/23 }}</ref> Later, the [[naturalist]] and explorer [[Alexander von Humboldt]] recognized the coevolution of living organisms, climate, and Earth's crust.<ref name=CapraWeb /> In the twentieth century, [[Vladimir Vernadsky]] formulated a theory of Earth's development that is now one of the foundations of ecology. Vernadsky was a Ukrainian [[geochemist]] and was one of the first scientists to recognize that the oxygen, nitrogen, and carbon dioxide in the Earth's atmosphere result from biological processes. During the 1920s he published works arguing that living organisms could reshape the planet as surely as any physical force. Vernadsky was a pioneer of the scientific bases for the environmental sciences.<ref>S.R. Weart, 2003, ''The Discovery of Global Warming'', Cambridge, Harvard Press</ref> His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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"How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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“被称为盖亚的全球生物地球化学/气候系统是如何及时发生变化的?它的历史是什么?盖亚能够在一个时间尺度上保持系统的稳定性,但是在更长的时间尺度上仍然经历矢量变化吗?如何利用地质记录来检验这些问题? ”<br />
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"What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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“盖亚的结构是什么?这些反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由在任何特定时间进行的学科研究务实地决定的,还是有一些部分应该被认为是最真实的,以了解盖亚随着时间的推移包含进化中的生物体?盖亚系统这些不同部分之间的反馈是什么? 对盖亚作为全球生态系统的结构和生命的生产力来说,物质的近乎封闭意味着什么? ”<br />
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Also in the turn to the 20th century [[Aldo Leopold]], pioneer in the development of modern [[environmental ethics]] and in the movement for [[wilderness]] conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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"How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
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“盖亚过程和现象的模型如何与现实相关,它们如何帮助解决和理解盖亚?雏菊世界的成果如何转移到现实世界?什么是“雏菊”的主要候选人?我们发现雏菊与否对盖亚理论重要吗?我们应该怎样寻找雏菊,我们应该加紧寻找吗?如何利用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖亚机制? ”<br />
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{{quotation|It is at least not impossible to regard the earth's parts—soil, mountains, rivers, atmosphere etc,—as organs or parts of organs of a coordinated whole, each part with its definite function. And if we could see this whole, as a whole, through a great period of time, we might perceive not only organs with coordinated functions, but possibly also that process of consumption as replacement which in biology we call metabolism, or growth. In such case we would have all the visible attributes of a living thing, which we do not realize to be such because it is too big, and its life processes too slow.| Stephan Harding | ''Animate Earth''.<ref>Harding, Stephan. ''Animate Earth Science, Intuition and Gaia''. Chelsea Green Publishing, 2006, p. 44. {{ISBN|1-933392-29-0}}</ref>}}<br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise entropy production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
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1997年,泰勒·沃尔克认为,盖亚系统几乎不可避免地会产生,这是一种向远离平衡的稳态演化的结果,这种平衡状态使熵产生最大化,克莱顿(2004)同意这样的说法:“自稳态行为可以从与行星反照率相关的MEP状态中产生”;“……一个如盖亚假说所述,处于MEP状态的生物地球很可能导致地球系统在长时间尺度上的近稳态行为。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。<br />
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Another influence for the Gaia hypothesis and the [[environmental movement]] in general came as a side effect of the [[Space Race]] between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph ''[[Earthrise]]'' taken by astronaut [[William Anders]] in 1968 during the [[Apollo 8]] mission became, through the [[Overview Effect]] an early symbol for the global ecology movement.<ref>[http://digitaljournalist.org/issue0309/lm11.html 100 Photographs that Changed the World by Life - The Digital Journalist]</ref><br />
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盖亚假说和[[环境运动]]的另一个总体影响来自苏联和美利坚合众国之间[[太空竞赛]]的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球的整体面貌。1968年宇航员[[William Anders]]在[[Apollo 8]]任务期间拍摄的照片“[[地球升起]”,通过[[概述效果]]成为全球生态运动的早期标志<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<br />
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第四次关于盖亚假说的国际会议,由北弗吉尼亚地区公园管理局和其他机构主办,于2006年10月在弗吉尼亚州乔治梅森大学的阿灵顿校区举行。<br />
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===Formulation of the hypothesis假说形成===<br />
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[[File:James Lovelock in 2005.jpg|thumb|[[James Lovelock]], 2005]]<br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
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马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。Lynn Margulis是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the [[Jet Propulsion Laboratory]] in California on methods of detecting [[life on Mars (planet)|life on Mars]].<ref name="Lovelock1965">{{cite journal | author = Lovelock, J.E. | date = 1965 | title = A physical basis for life detection experiments | journal = [[Nature (journal)|Nature]] | volume = 207 | issue = 7 | pages = 568–570 | doi = 10.1038/207568a0 | pmid=5883628|bibcode = 1965Natur.207..568L | ref = harv}}</ref><ref>{{Cite web |url=http://www.jameslovelock.org/page4.html |title=Geophysiology |access-date=2007-05-05 |archive-url=https://web.archive.org/web/20070506073502/http://www.jameslovelock.org/page4.html |archive-date=2007-05-06 |url-status=dead }}</ref> The first paper to mention it was ''Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life'', co-authored with C.E. Giffin.<ref>{{cite journal | author1 = Lovelock, J.E. | author2 = Giffin, C.E. | date = 1969 | title = Planetary Atmospheres: Compositional and other changes associated with the presence of Life | journal = Advances in the Astronautical Sciences | volume = 25 | pages = 179–193 | isbn = 978-0-87703-028-7 | ref = harv}}</ref> A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the [[Pic du Midi de Bigorre|Pic du Midi observatory]], planets like Mars or Venus had atmospheres in [[chemical equilibrium]]. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
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这次会议将盖亚假说作为一种科学和隐喻的手段,来理解我们如何开始解决21世纪的问题,如气候变化和持续的环境破坏。<br />
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Lovelock formulated the ''Gaia Hypothesis'' in journal articles in 1972<ref name="J1972">{{cite journal | author = J. E. Lovelock | title = Gaia as seen through the atmosphere | date = 1972 | journal = [[Atmospheric Environment]] | volume = 6 | issue = 8 | pages = 579–580 | doi = 10.1016/0004-6981(72)90076-5 | ref = harv|bibcode = 1972AtmEn...6..579L }}</ref> and 1974,<ref name="lovelock1974" /> followed by a popularizing 1979 book ''Gaia: A new look at life on Earth''. An article in the ''[[New Scientist]]'' of February 6, 1975,<ref>Lovelock, John and Sidney Epton, (February 8, 1975). "The quest for Gaia". [https://books.google.com/books?id=pnV6UYEkU4YC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false New Scientist], p. 304.</ref> and a popular book length version of the hypothesis, published in 1979 as ''The Quest for Gaia'', began to attract scientific and critical attention.<br />
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Lovelock called it first the Earth feedback hypothesis,<ref name="Lovelock01">{{harvnb|Lovelock, James|2001}}</ref> and it was a way to explain the fact that combinations of chemicals including [[oxygen]] and [[methane]] persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as Ford Doolittle, Richard Dawkins and Stephen Jay Gould. Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists, He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as autopoietic or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole. With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<br />
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在最初几乎没有引起科学家的注意之后(从1969年到1977年) ,有一段时间,最初的盖亚假说受到了一些科学家的批评,如福特杜利特,理查德道金斯和史蒂芬·古尔德。洛夫洛克说,因为他的假说是以一位希腊女神的名字命名的,并得到许多非科学家的拥护,他想知道实现自我调节体内平衡的实际机制。在为盖亚辩护时,戴维•阿布拉姆认为,古尔德忽视了一个事实,即“机制”本身就是一个隐喻——尽管这个隐喻极其常见,而且往往不为人所知——这个隐喻让我们把自然和生命系统看作是由外部组织和建造的机器(而不是自动生成或自组织现象)。根据阿布拉姆的说法,机械隐喻使我们忽略了生命实体的活跃性或代表性,而盖亚假说的有机隐喻强调了生物群和整个生物圈的活跃性。关于盖亚的因果关系,洛夫洛克认为没有单一的机制是负责任的,各种已知机制之间的联系可能永远不会被人知道,这在生物学和生态学的其他领域是理所当然地被接受的,并且由于其他原因,特定的敌意是保留给他自己的假设的。<br />
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[[File:Lynn Margulis.jpg|thumb|left|[[Lynn Margulis]]]]<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of greedy reductionism in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<br />
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除了澄清他的语言和理解什么是生命形式,洛夫洛克自己把大部分的批评归因于他的批评者缺乏对非线性数学的理解,以及贪婪还原主义的线性化形式,在这种形式中,所有事件都必须立即归因于事件发生之前的特定原因。他还表示,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,以及一些自我调节现象可能无法在数学上解释。<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<ref>{{cite journal | first1=W.D. | last1=Hamilton | first2=T.M. | last2=Lenton | title=Spora and Gaia: how microbes fly with their clouds | journal=Ethology Ecology & Evolution | volume=10 | pages=1–16 | date=1998 | issue=1 | url=http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | format=PDF | doi=10.1080/08927014.1998.9522867 | ref=harv | url-status=dead | archiveurl=https://web.archive.org/web/20110723055017/http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | archivedate=2011-07-23 }}</ref><br />
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Evolutionary biologist W. D. Hamilton called the concept of Gaia Copernican, adding that it would take another Newton to explain how Gaian self-regulation takes place through Darwinian natural selection. More recently Ford Doolittle building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis. <br />
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进化生物学家W.D.Hamilton称盖亚为哥白尼的概念,并补充说,需要另一个牛顿来解释盖亚的自我调节是如何通过达尔文的自然选择发生的。最近,Ford Doolittle在他和Inkpen的ITSNTS(这是歌手而不是歌曲)的建议中提出,差异持续性可以在自然选择进化中起到与差异生殖相似的作用,从而为自然选择理论和盖亚假说之间提供了一种可能的调和。 <br />
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In 1971 [[microbiologist]] Dr. [[Lynn Margulis]] joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet.<ref name="Turney, Jon 2003">{{cite book |author=Turney, Jon |title=Lovelock and Gaia: Signs of Life |publisher=Icon Books |location=UK |date=2003 |isbn=978-1-84046-458-0 |url-access=registration |url=https://archive.org/details/lovelockgaiasign0000turn }}</ref> The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of [[eukaryote|eukaryotic]] [[organelle]]s and her contributions to the [[endosymbiotic theory]], nowadays accepted. Margulis dedicated the last of eight chapters in her book, ''The Symbiotic Planet'', to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal Climatic Change in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it. to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background" The CLAW hypothesis, In 2009 the Medea hypothesis was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<br />
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盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论据是,生命对环境产生了有害或不稳定的影响,而不是采取行动加以调节。为了“令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在背景下。”爪假说,2009年提出的美狄亚假说:生命对行星条件有高度有害的(生物杀灭)影响,与盖亚假说直接相反。 <br />
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James Lovelock called his first proposal the ''Gaia hypothesis'' but has also used the term ''Gaia theory''. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments<ref name="J1990">{{cite journal | author = J. E. Lovelock | title = Hands up for the Gaia hypothesis | date = 1990 | journal = [[Nature (journal)|Nature]] | volume = 344 | issue = 6262 | pages = 100–2 | doi = 10.1038/344100a0|bibcode = 1990Natur.344..100L | ref = harv}}</ref> and provided a number of useful predictions.<ref name="Volk2003">{{cite book |author=Volk, Tyler |title=Gaia's Body: Toward a Physiology of Earth |publisher=[[MIT Press]] |location=Cambridge, Massachusetts |date=2003 |isbn=978-0-262-72042-7 }}</ref> In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating.<ref name="vanishing255"/><br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it". Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works". This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<br />
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2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新想法,并倡导一种整体的方法来研究地球”。在其他地方,他提出了自己的结论:“盖亚假说并不是我们这个世界如何运转的精确图像”。这种说法需要被理解为是指盖亚的“强”和“中”形式,生物群遵循的原则是使地球成为最佳(强度5)或有利于生命(强度4),或是作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚的两种较弱的形式共同进化盖亚和有影响力的盖亚,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚”一词是没有用的两种形式已经被自然选择和适应过程所接受和解释。<br />
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===First Gaia conference第一次盖亚会议===<br />
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In 1985, the first public symposium on the Gaia hypothesis, ''Is The Earth A Living Organism?'' was held at [[University of Massachusetts Amherst]], August 1–6.<ref>{{cite news |last=Joseph |first=Lawrence E. |title=Britain's Whole Earth Guru |work=The New York Times Magazine |date=November 23, 1986 |url=https://www.nytimes.com/1986/11/23/magazine/britain-s-whole-earth-guru.html |accessdate=1 December 2013}}</ref> The principal sponsor was the [[National Audubon Society]]. Speakers included James Lovelock, [[George Wald]], [[Mary Catherine Bateson]], [[Lewis Thomas]], [[John Todd (Canadian biologist)|John Todd]], Donald Michael, [[Christopher Bird]], [[Thomas Berry]], [[David Abram]], [[Michael A. Cohen|Michael Cohen]], and William Fields. Some 500 people attended.<ref>Bunyard, Peter (1996), "Gaia in Action: Science of the Living Earth" (Floris Books)</ref><br />
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1985年,关于盖亚假说的第一次公开研讨会,“地球是一个活的有机体吗?”在马萨诸塞大学阿默斯特举行 <br />
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===Second Gaia conference第二次盖亚会议===<br />
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In 1988, [[climatology|climatologist]] [[Stephen Schneider]] organised a conference of the [[American Geophysical Union]]. The first Chapman Conference on Gaia,<ref name="ReferenceB"/> was held in San Diego, California on March 7, 1988.<br />
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1988年,climatology和Stephen Schneider组织了一次美国地球物理联合会会议。关于盖亚的第一次查普曼会议 <br />
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During the "philosophical foundations" session of the conference, [[David Abram]] spoke on the influence of metaphor in science, and of the Gaia hypothesis as offering a new and potentially game-changing metaphorics, while [[James Kirchner]] criticised the Gaia hypothesis for its imprecision. Kirchner claimed that Lovelock and Margulis had not presented one Gaia hypothesis, but four -<br />
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在会议的“哲学基础”会议上,David Abram谈到了隐喻在科学中的影响,盖亚假说提供了一种新的、可能改变游戏规则的隐喻,而James Kirchner则批评盖亚假说的不精确性。基什纳声称,洛夫洛克和马古利斯提出的盖亚假说不是一个,而是四个- <br />
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* [[Coevolution|CoEvolutionary]] Gaia: that life and the environment had evolved in a coupled way. Kirchner claimed that this was already accepted scientifically and was not new.<br />
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* [[Homeostatic]] Gaia: that life maintained the stability of the natural environment, and that this stability enabled life to continue to exist.<br />
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* [[Geophysics|Geophysical]] Gaia: that the Gaia hypothesis generated interest in geophysical cycles and therefore led to interesting new research in terrestrial geophysical dynamics.<br />
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* Optimising Gaia: that Gaia shaped the planet in a way that made it an optimal environment for life as a whole. Kirchner claimed that this was not testable and therefore was not scientific.<br />
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盖亚:生命和环境是以耦合的方式进化的。基什内尔声称,这已经被科学界接受,并不是什么新鲜事。 <br />
盖亚:生命维持着自然环境的稳定,这种稳定性使生命得以继续存在。 <br />
盖亚:盖亚假说引起了人们对地球物理周期的兴趣,因此导致了地球物理动力学中有趣的新研究。 <br />
优化盖亚:盖亚塑造了地球,使之成为整个生命的最佳环境。基什内尔声称,这是不可测试的,因此是不科学的。 <br />
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Of Homeostatic Gaia, Kirchner recognised two alternatives. "Weak Gaia" asserted that life tends to make the environment stable for the flourishing of all life. "Strong Gaia" according to Kirchner, asserted that life tends to make the environment stable, ''to enable'' the flourishing of all life. Strong Gaia, Kirchner claimed, was untestable and therefore not scientific.<ref>{{cite journal | bibcode=1989RvGeo..27..223K | doi = 10.1029/RG027i002p00223 | title=The Gaia hypothesis: Can it be tested? | date=1989 | last1=Kirchner | first1=James W. | journal=Reviews of Geophysics | volume=27 | issue=2 | pages=223 | ref=harv}}</ref><br />
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基什内尔发现了两种选择“软弱的盖亚”断言,为了所有生命的繁衍,生命往往会使环境变得稳定根据基什内尔的说法,“强大的盖亚”断言,生命趋向于使环境稳定,“使”所有生命繁荣昌盛。基什内尔声称,强大的盖亚是不稳定的,因此不科学。 <br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the [[Daisyworld]] Model (and its modifications, above) as evidence against most of these criticisms.<ref name="daisyworld"/> Lovelock said that the Daisyworld model "demonstrates that self-regulation of the global environment can emerge from competition amongst types of life altering their local environment in different ways".<ref>{{cite journal | pmid=10968941 | date=2000 | last1=Lenton | first1=TM | last2=Lovelock | first2=JE | s2cid=5486128 | title=Daisyworld is Darwinian: Constraints on adaptation are important for planetary self-regulation | volume=206 | issue=1 | pages=109–14 | doi=10.1006/jtbi.2000.2105 | journal=Journal of Theoretical Biology | ref=harv}}</ref><br />
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然而,洛夫洛克和其他支持盖亚的科学家,确实试图反驳这种说法,即这个假设是不科学的,因为不可能通过受控实验来检验它。例如,针对盖亚是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修改,洛夫洛克说,雏菊世界模型“证明了全球环境的自我调节可以通过不同方式改变当地环境的生活类型之间的竞争产生”。 <br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of [[teleology|teleologism]] ceased, following this conference.<br />
洛夫洛克谨慎地提出了盖亚假说的一个版本,没有声称盖亚有意或有意识地维持着生命生存所需的复杂平衡。看来盖亚“故意”的行为是他最受欢迎的第一本书中的隐喻性陈述,并不是字面意思。盖亚假说的这一新说法更为科学界所接受。在这次会议之后,[[目的论|目的论]]的大多数指控都停止了。<br />
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===Third Gaia conference第三次盖亚会议===<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000,<ref>{{cite news|last=Simón|first=Federico|title=GEOLOGÍA Enfoque multidisciplinar La hipótesis Gaia madura en Valencia con los últimos avances científicos|journal=El País|date=21 June 2000|url=http://elpais.com/diario/2000/06/21/futuro/961538404_850215.html|accessdate=1 December 2013|language=spanish}}</ref> the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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The major questions were:<ref>{{cite web|title=General Information Chapman Conference on the Gaia Hypothesis University of Valencia Valencia, Spain June 19-23, 2000 (Monday through Friday) |url=http://www.agu.org/meetings/chapman/chapman_archive/cc00bcall.html |work=AGU Meetings |accessdate=7 January 2017 |author=American Geophysical Union }}</ref><br />
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# "How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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# "What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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# "How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
“被称为盖亚的全球生物地球化学/气候系统是如何随时间变化的?它的历史是什么?盖亚能在一个时间尺度上保持系统的稳定性,但在较长的时间尺度上仍能经历向量变化吗?如何利用地质记录来检验这些问题?” <br />
“盖亚的结构是什么?反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由任何给定时间正在进行的任何学科研究实际确定的,还是有一组应该被视为最真实的部分来理解盖亚,即随着时间的推移包含进化中的有机体?盖亚系统的这些不同部分之间的反馈是什么?物质的接近封闭对盖亚作为全球生态系统的结构和生命的生产力意味着什么?” <br />
“盖亚过程和现象的模型如何与现实联系起来,它们如何帮助解决和理解盖亚?雏菊世界的结果如何传递到真实世界?“雏菊”的主要候选对象是什么?我们是否找到雏菊对盖亚理论有意义吗?我们应该如何寻找雏菊,我们应该加强搜索?如何使用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖安机制?” <br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise [[entropy]] production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
1997年,泰勒·沃尔克认为,盖安系统几乎不可避免地会产生,这是朝着使熵产量最大化的远非平衡平衡平衡状态演化的结果,克莱顿(2004)同意这样的说法:“自稳行为可以从与行星反照率相关的MEP状态中产生”;“……生物地球在MEP状态下的行为很可能导致地球系统在长时间尺度上的近稳态行为,正如盖亚假说所述”。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。 <br />
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===Fourth Gaia conference第四次盖亚会议===<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<ref>{{cite web|title=Gaia Theory Conference at George Mason University Law School|url=http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|accessdate=1 December 2013|author=Official Site of Arlington County Virginia|archive-url=https://web.archive.org/web/20131203043657/http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|archive-date=2013-12-03|url-status=dead}}</ref><br />
第四届盖亚假说国际会议于2006年10月在乔治梅森大学阿灵顿分校举行,会议由北弗吉尼亚州公园管理局和其他机构赞助。 <br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。林恩 马古拉斯是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
这次会议将盖亚假说作为一种科学和隐喻来探讨,以此来理解我们如何着手解决21世纪的问题,如气候变化和持续的环境破坏<br />
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==Criticism批评==<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as [[Ford Doolittle]],<ref name=":1">{{Cite journal|last=Doolittle|first=W. F.|year=1981|title=Is Nature Really Motherly|url=|journal=The Coevolution Quarterly|volume=Spring|pages=58–63|via=}}</ref> [[Richard Dawkins]]<ref name=":2">{{Cite book|title=The Extended Phenotype: the Long Reach of the Gene|last=Dawkins|first=Richard|publisher=Oxford University Press|year=1982|isbn=978-0-19-286088-0|location=|pages=}}</ref> and [[Stephen Jay Gould]].<ref name="ReferenceB">Turney, Jon. "Lovelock and Gaia: Signs of Life" (Revolutions in Science)</ref> Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists,<ref name="Lovelock01"/> the Gaia hypothesis was interpreted as a [[neo-Pagan]] [[religion]]. Many scientists in particular also criticised the approach taken in his popular book ''Gaia, a New Look at Life on Earth'' for being [[teleology|teleological]]—a belief that things are purposeful and aimed towards a goal. Responding to this critique in 1990, Lovelock stated, "Nowhere in our writings do we express the idea that planetary self-regulation is purposeful, or involves foresight or planning by the [[biota (ecology)|biota]]".<br />
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最初很少受到科学家的关注(从1969年到1977年),此后的一段时间里,最初的盖亚假说受到了许多科学家的批评,比如福特·杜利特,理查德·道金斯和斯蒂芬·杰伊·古尔德洛夫洛克曾说过,因为他的假设是以希腊女神的名字命名的,新盖亚假说被许多非教派的科学家解释为。特别是许多科学家还批评了他的畅销书《盖亚》中采用的方法,认为地球上的生命是目的论的,认为事物是有目的的,是有目的的。洛夫洛克在1990年回应这一批评时说:“在我们的著作中我们没有任何地方表达行星自我调节是有目的的,或涉及生物群的远见或计划。”<br />
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[[Stephen Jay Gould]] criticised Gaia as being "a metaphor, not a mechanism."<ref name="Gould 1997">{{cite journal |author=Gould S.J. |title=Kropotkin was no crackpot |journal=Natural History |volume=106 |pages=12–21 |date=June 1997 |url=http://libcom.org/library/kropotkin-was-no-crackpot |ref=harv}}</ref> He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as [[autopoiesis|autopoietic]] or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole.<ref>Abram, D. (1988) "The Mechanical and the Organic: On the Impact of Metaphor in Science" in Scientists on Gaia, edited by Stephen Schneider and Penelope Boston, Cambridge, Massachusetts: MIT Press, 1991</ref><ref>{{cite web|url=http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |title=The Mechanical and the Organic |accessdate=August 27, 2012 |url-status=dead |archiveurl=https://web.archive.org/web/20120223165936/http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |archivedate=February 23, 2012 }}</ref> With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<ref name="Lovelock, James 2001">Lovelock, James (2001), ''Homage to Gaia: The Life of an Independent Scientist'' (Oxford University Press)</ref><br />
史蒂芬·杰伊·古尔德批评盖亚是“一种隐喻,而不是一种机制。”他想知道实现自我调节内稳态的实际机制。在为盖亚辩护时,大卫·艾布拉姆认为古尔德忽略了一个事实,即“机制”本身就是一个隐喻——尽管这是一个非常常见且常常未被人认识的隐喻——它使我们把自然和生命系统看作是从外部组织和建造的机器(而不是自动或自组织的)现象)。艾布拉姆认为,机械隐喻使我们忽视了生命实体的活动性或能动性,而盖亚假说的有机体隐喻强调了生物群和生物圈作为一个整体的能动性。关于盖亚的因果关系,洛夫洛克认为没有单一的机制负责各种已知机制之间的联系可能永远不为人所知,这一点在其他生物学和生态学领域都是理所当然的,而具体的敌意是出于其他原因留给他自己的假设的<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of [[greedy reductionism]] in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<ref name="Lovelock, James 2001"/><br />
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除了澄清自己的语言和对生命形式的理解之外,洛夫洛克自己将大部分批评归咎于批评家对非线性数学的缺乏理解,以及贪婪还原论的线性化形式,在这种形式中,所有事件都必须在事实发生之前立即归因于特定的原因。他还指出,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,有些自我调节的现象可能无法用数学解释 <br />
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===Natural selection and evolution自然选择和进化===<br />
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Lovelock has suggested that global biological feedback mechanisms could evolve by [[natural selection]], stating that organisms that improve their environment for their survival do better than those that damage their environment. However, in the early 1980s, [[Ford Doolittle|W. Ford Doolittle]] and [[Richard Dawkins]] separately argued against this aspect of Gaia. Doolittle argued that nothing in the [[genome]] of individual organisms could provide the feedback mechanisms proposed by Lovelock, and therefore the Gaia hypothesis proposed no plausible mechanism and was unscientific.<ref name=":1" /> Dawkins meanwhile stated that for organisms to act in concert would require foresight and planning, which is contrary to the current scientific understanding of evolution.<ref name=":2" /> Like Doolittle, he also rejected the possibility that feedback loops could stabilize the system.<br />
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洛夫洛克提出,全球生物反馈机制可以通过自然选择而进化,他指出,为生存而改善环境的生物比那些破坏环境的生物做得更好。然而,在20世纪80年代早期,W·福特·杜立德和理查德·道金斯分别反对盖亚的这一方面。杜立德认为,单个生物体的基因组中没有任何东西能够提供洛夫洛克提出的反馈机制,因此盖亚假说没有提出任何合理的机制,是不科学的。道金斯同时指出,要使有机体协同行动,就需要有远见和计划,这与当前科学界对进化论的理解相悖和杜立德一样,他也拒绝了反馈回路可以稳定系统的可能性。<br />
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[[Lynn Margulis]], a microbiologist who collaborated with Lovelock in supporting the Gaia hypothesis, argued in 1999, that "[[Charles Darwin|Darwin]]'s grand vision was not wrong, only incomplete. In accentuating the direct competition between individuals for resources as the primary selection mechanism, Darwin (and especially his followers) created the impression that the environment was simply a static arena". She wrote that the composition of the Earth's atmosphere, hydrosphere, and lithosphere are regulated around "set points" as in [[homeostasis]], but those set points change with time.<ref name="ReferenceA">Margulis, Lynn. Symbiotic Planet: A New Look At Evolution. Houston: Basic Book 1999</ref><br />
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Lynn Margulis,一位与Lovelock合作支持盖亚假说的微生物学家,在1999年指出,“达尔文的宏伟愿景没有错,只是不完整。达尔文(特别是他的追随者)强调个人之间对资源的直接竞争是主要的选择机制,他给人的印象是环境只是一个静态的竞技场”。她写道,地球大气、水圈和岩石圈的组成都是围绕着“设定点”来调节的,就像在体内平衡中一样,但是这些设定点会随着时间的推移而变化 <br />
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Evolutionary biologist [[W. D. Hamilton]] called the concept of Gaia [[Nicolaus Copernicus|Copernican]], adding that it would take another [[Isaac Newton|Newton]] to explain how Gaian self-regulation takes place through Darwinian [[natural selection]].<ref name=vanish09>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, pp. 195-197. {{ISBN|978-0-465-01549-8}}</ref>{{better source|date=September 2012|reason=it should be possible to find the original place where Hamilton said this}} More recently [[Ford Doolittle]] building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal<ref name="ITSNTS">Doolittle WF, Inkpen SA. Processes and patterns of interaction as units of selection: An introduction to ITSNTS thinking. [https://www.pnas.org/content/115/16/4006 PNAS April 17, 2018 115 (16)] 4006-4014 </ref> proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis<ref name="Darwinizing Gaia">Doolittle WF. Darwinizing Gaia. [https://doi.org/10.1016/j.jtbi.2017.02.015 Journal of Theoretical BiologyVolume 434], 7 December 2017, Pages 11-19 </ref>. <br />
进化生物学家汉密尔顿称盖亚哥白尼为盖亚的概念,他补充说,需要另一个牛顿来解释盖安的自我调节是如何通过达尔文的自然选择发生的。通过自然选择在进化过程中的繁殖,从而为自然选择理论和盖亚假说提供了可能的调和。 <br />
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===Criticism in the 21st century21世纪的批评===<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal ''Climatic Change'' in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it.<ref name="kirchner2002"/><ref name="volk2002"/> Several recent books have criticised the Gaia hypothesis, expressing views ranging from "... the Gaia hypothesis lacks unambiguous observational support and has significant theoretical difficulties"<ref>{{cite book |last=Waltham |first=David |authorlink=David Waltham |date=2014 |title=Lucky Planet: Why Earth is Exceptional – and What that Means for Life in the Universe |url=https://archive.org/details/luckyplanetwhyea0000walt |location= |publisher=Icon Books |page= |isbn=9781848316560 |accessdate= |url-access=registration }}</ref> to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background"<ref name="beerling2007"/> to "The Gaia hypothesis is supported neither by evolutionary theory nor by the empirical evidence of the geological record".<ref>{{cite book |last1=Cockell |first1=Charles |authorlink1=Charles Cockell |last2=Corfield |first2=Richard |last3=Dise |first3= Nancy |last4=Edwards |first4=Neil |last5=Harris |first5=Nigel |date=2008 |title= An Introduction to the Earth-Life System |url= http://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/palaeontology-and-life-history/introduction-earth-life-system |location=Cambridge (UK) |publisher= Cambridge University Press |page= |isbn= 9780521729536 |accessdate= }}</ref> The [[CLAW hypothesis]],<ref name="CLAW87" /> initially suggested as a potential example of direct Gaian feedback, has subsequently been found to be less credible as understanding of [[cloud condensation nuclei]] has improved.<ref>{{Citation |last1= Quinn |first1=P.K. |last2= Bates |first2=T.S. |title =The case against climate regulation via oceanic phytoplankton sulphur emissions |journal =Nature |volume=480 |issue=7375 |pages =51–56 |date = 2011 |doi=10.1038/nature10580|bibcode = 2011Natur.480...51Q |pmid=22129724|url=https://zenodo.org/record/1233319 }}</ref> In 2009 the [[Medea hypothesis]] was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<ref>Peter Ward (2009), ''The Medea Hypothesis: Is Life on Earth Ultimately Self-Destructive?'', {{ISBN|0-691-13075-2}}</ref><br />
盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论点是许多例子,其中生命对环境产生了有害或不稳定的影响,而不是采取行动来调节它。最近几本书批评了盖亚假说,表达了从“盖亚假说缺乏明确的观察支持,并且有重大的理论困难“到”令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在背景中“到”盖亚假说既没有进化论的支持,也没有地质记录的经验证据的支持。爪假说最初被认为是盖安直接反馈的一个潜在例子,后来被发现对云的理解不那么可信凝聚核已经得到了改善2009年,美狄亚假说被提出:生命对行星的状况有非常有害的(杀生的)影响,这与盖亚假说直接相反 <br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it".<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=209 |isbn=9780691121581 |accessdate= }}</ref> Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works".<ref>{{Citation |last= Tyrrell |first = Toby |title =Gaia: the verdict is… |journal = New Scientist |volume = 220 |issue = 2940 |pages = 30–31 |date= 26 October 2013 |doi=10.1016/s0262-4079(13)62532-4}}</ref> This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=208 |isbn=9780691121581 |accessdate= }}</ref><br />
2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新思想,并倡导一种研究地球的整体方法。”在其他地方,他提出了自己的结论:“盖亚假说并不是一个关于如何进行的精确描述我们的世界在运转。”这种说法需要被理解为是指盖亚的“强大”和“温和”形式,生物群遵循的原则是使地球处于最佳状态(强度5)或有利于生命(强度4),或者它作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚的两种较弱的形式共同进化盖亚和有影响力的盖亚,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚”一词是没有用的两种形式已经被自然选择和适应过程所接受和解释 <br />
Category:Cybernetics<br />
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类别: 控制论<br />
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Category:Ecological theories<br />
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范畴: 生态学理论<br />
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==See also==<br />
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Category:Superorganisms<br />
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类别: 超级有机体<br />
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{{Portal|Environment|Earth sciences|Geography}}<br />
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Category:Climate change feedbacks<br />
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类别: 气候变化反馈<br />
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Category:1965 introductions<br />
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类别: 1965年引言<br />
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* {{annotated link|Biocoenosis}}<br />
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Category:Biogeochemistry<br />
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类别: 生物地球化学<br />
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* {{annotated link|Earth science}}<br />
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* {{annotated link|Environmentalism}}<br />
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Category:Biological hypotheses<br />
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Category:Astronomical hypotheses<br />
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Category:Meteorological hypotheses<br />
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类别: 气象假说<br />
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<small>This page was moved from [[wikipedia:en:Gaia hypothesis]]. Its edit history can be viewed at [[盖亚假说/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E7%9B%96%E4%BA%9A%E5%81%87%E8%AF%B4&diff=18461盖亚假说2020-11-16T09:03:51Z<p>Henry:</p>
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<div>此词条暂由Henry翻译。<br />
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{{short description|Hypothesis that living organisms interact with their surroundings in a self-regulating system}}<br />
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[[File:The Earth seen from Apollo 17.jpg|thumb|The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth]]'s conditions, as the Earth is the only planet currently known to harbour life (''[[The Blue Marble]]'', 1972 [[Apollo 17]] photograph)]]<br />
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The study of planetary habitability is partly based upon extrapolation from knowledge of the [[Earth's conditions, as the Earth is the only planet currently known to harbour life (The Blue Marble, 1972 Apollo 17 photograph)]]<br />
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行星可居住性的研究部分基于对[[地球条件]的了解推断,因为地球是目前已知的唯一一颗拥有生命的行星 <br />
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The '''Gaia hypothesis''' {{IPAc-en|ˈ|ɡ|aɪ|.|ə}}, also known as the '''Gaia theory''' or the '''Gaia principle''', proposes that living [[organism]]s interact with their [[Inorganic compound|inorganic]] surroundings on [[Earth]] to form a [[Synergy|synergistic]] and [[Homeostasis|self-regulating]], [[complex system]] that helps to maintain and perpetuate the conditions for [[life]] on the planet.<br />
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The Gaia hypothesis , also known as the Gaia theory or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet.<br />
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盖亚假说(又称盖亚理论或盖亚原理)提出,生物体与地球上的无机环境相互作用,形成一个协同和自我调节的复杂系统,有助于维持和延续地球上的生命条件。<br />
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The hypothesis was formulated by the chemist [[James Lovelock]]<ref name="J1972" /> and co-developed by the microbiologist [[Lynn Margulis]] in the 1970s.<ref name="lovelock1974">{{cite journal|last1=Lovelock|first1=J.E.|last2=Margulis|first2=L.|title=Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis|journal=Tellus|date=1974|volume=26|series=Series A|issue=1–2|pages=2–10|doi=10.1111/j.2153-3490.1974.tb01946.x|publisher=International Meteorological Institute|location=Stockholm|issn=1600-0870|ref=harv|bibcode=1974Tell...26....2L}}</ref> Lovelock named the idea after [[Gaia]], the primordial goddess who personified the Earth in [[Greek mythology]]. In 2006, the [[Geological Society of London]] awarded Lovelock the [[Wollaston Medal]] in part for his work on the Gaia hypothesis.<ref>{{cite web|title=Wollaston Award Lovelock|url=https://www.geolsoc.org.uk/About/History/Awards-Citations-Replies-2001-Onwards/2006-Awards-Citations-Replies|accessdate=19 October 2015}}</ref><br />
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The hypothesis was formulated by the chemist James Lovelock Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis.<br />
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这个假设是由化学家詹姆斯 洛夫洛克提出的,他以希腊神话中地球的化身盖亚的名字命名了这个想法。2006年,伦敦地质学会授予洛夫洛克沃拉斯顿勋章,部分原因是他在<font color="#ff8000"> 盖亚假说Gaia hypothesis</font>方面的工作。 <br />
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Topics related to the hypothesis include how the [[biosphere]] and the [[evolution]] of organisms affect the stability of [[global temperature]], [[salinity]] of [[seawater]], [[atmospheric oxygen]] levels, the maintenance of a [[hydrosphere]] of liquid water and other environmental variables that affect the [[habitability of Earth]].<br />
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Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth.<br />
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与该假设有关的主题包括生物圈和生物体的进化如何影响全球温度的稳定性、海水的盐度、大气中的氧含量、液态水的水圈的维持以及其他影响地球宜居性的环境变量。<br />
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The Gaia hypothesis was initially criticized for being [[teleological]] and against the principles of [[natural selection]], but later refinements aligned the Gaia hypothesis with ideas from fields such as [[Earth system science]], [[biogeochemistry]] and [[systems ecology]].<ref name="Turney, Jon 2003"/><ref name="Schwartzman2002">{{cite book |author=Schwartzman, David |title=Life, Temperature, and the Earth: The Self-Organizing Biosphere |publisher=Columbia University Press |date=2002 |isbn=978-0-231-10213-1 }}</ref><ref>Gribbin, John (1990), "Hothouse earth: The greenhouse effect and Gaia" (Weidenfeld & Nicolson)</ref> Lovelock also once described the "geophysiology" of the Earth.<ref name="agesofgaia">Lovelock, James, (1995) "The Ages of Gaia: A Biography of Our Living Earth" (W.W.Norton & Co)</ref>{{Explain|date=December 2017}} Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<ref name="kirchner2002">{{Citation |last= Kirchner |first = James W. |title =Toward a future for Gaia theory |journal=[[Climatic Change (journal)|Climatic Change]] |volume = 52 |issue = 4 |pages = 391–408 |date = 2002 | doi = 10.1023/a:1014237331082 }}</ref><ref name="volk2002">{{Citation |last= Volk |first = Tyler |title =The Gaia hypothesis: fact, theory, and wishful thinking |journal = Climatic Change |volume = 52 |issue = 4 |pages = 423–430 |date = 2002 | doi = 10.1023/a:1014218227825 }}</ref><ref name="beerling2007">{{cite book |last=Beerling |first=David |authorlink=David Beerling|date=2007 |title=The Emerald Planet: How plants changed Earth's history |url=http://ukcatalogue.oup.com/product/9780192806024.do |location=Oxford|publisher=Oxford University Press |page= |isbn= 978-0-19-280602-4 |accessdate= }}</ref><br />
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The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Lovelock also once described the "geophysiology" of the Earth. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.<br />
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盖亚假说最初被批评为目的论和反对自然选择的原则,但后来的改进使盖亚假说与来自地球系统科学、生物地球化学和系统生态学等领域的想法相一致。洛夫洛克还曾经描述过地球的“地球物理学”。即便如此,盖亚假说仍然受到批评,今天许多科学家认为它只有微弱的支持,或与现有的证据相矛盾。<br />
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==Overview总览==<br />
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Gaian hypotheses suggest that organisms [[Co-evolution|co-evolve]] with their environment: that is, they "influence their [[abiotic]] environment, and that environment in turn influences the [[Biota (ecology)|biota]] by [[Darwinism|Darwinian process]]". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early [[Bacteria|thermo-acido-philic]] and [[methanogenic bacteria]] towards the oxygen-enriched [[atmosphere]] today that supports more [[Phanerozoic|complex life]].<br />
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Gaian hypotheses suggest that organisms co-evolve with their environment: that is, they "influence their abiotic environment, and that environment in turn influences the biota by Darwinian process". Lovelock (1995) gave evidence of this in his second book, showing the evolution from the world of the early thermo-acido-philic and methanogenic bacteria towards the oxygen-enriched atmosphere today that supports more complex life.<br />
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盖恩假说认为,生物体与其环境共同进化:也就是说,它们“影响它们的非生物环境,而环境反过来又通过达尔文的过程影响生物群”。Lovelock(1995)在他的第二本书中提供了证据,展示了从早期嗜酸和产甲烷细菌的世界向今天支持更复杂生命的富氧大气的进化。<br />
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A reduced version of the hypothesis has been called "influential Gaia"<ref name=":02">{{Cite journal|last=Lapenis|first=Andrei G.|year=2002|title=Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?|url=|journal=The Professional Geographer|volume=54 |issue=3|pages=379–391|via=[Peer Reviewed Journal]|doi=10.1111/0033-0124.00337}}</ref> in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the [[Biota (ecology)|biota]] influence certain aspects of the abiotic world, e.g. [[temperature]] and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<ref name=":02" /> and biogeochemical processes. An example is how the activity of [[Photosynthesis|photosynthetic]] bacteria during Precambrian times completely modified the [[Earth's atmosphere|Earth atmosphere]] to turn it aerobic, and thus supports the evolution of life (in particular [[eukaryotic]] life).<br />
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A reduced version of the hypothesis has been called "influential Gaia" in "Directed Evolution of the Biosphere: Biogeochemical Selection or Gaia?" by Andrei G. Lapenis, which states the biota influence certain aspects of the abiotic world, e.g. temperature and atmosphere. This is not the work of an individual but a collective of Russian scientific research that was combined into this peer reviewed publication. It states the coevolution of life and the environment through “micro-forces”<br />
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在《生物圈的定向进化: 生物地球化学选择还是盖亚? 》一书中,这一假说的简化版被称为“有影响力的盖亚”由安德烈·G·拉佩尼斯所著,他指出生物群影响着非生物世界的某些方面,例如:温度和大气。这不是一个人的工作,而是一个俄罗斯科学研究的集体,合并成这个同行评议的出版物。它通过“微观力量”阐述了生命与环境的共同进化<br />
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Since barriers existed throughout the twentieth century between Russia and the rest of the world, it is only relatively recently that the early Russian scientists who introduced concepts overlapping the Gaia hypothesis have become better known to the Western scientific community.<ref name=":02" /> These scientists include [[Piotr Kropotkin|Piotr Alekseevich Kropotkin]] (1842–1921) (although he spent much of his professional life outside Russia), Vasil’evich Rizpolozhensky (1847–1918), [[Vladimir Ivanovich Vernadsky]] (1863–1945), and Vladimir Alexandrovich Kostitzin (1886–1963).<br />
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由于二十世纪俄罗斯与世界其他地区之间存在着隔阂,直到最近,引进了盖亚假说重叠概念的早期俄罗斯科学家才为西方科学界所熟知 <br />
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The Gaia hypothesis posits that the Earth is a self-regulating complex system involving the biosphere, the atmosphere, the hydrospheres and the pedosphere, tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<br />
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盖亚假说认为,地球是一个自我调节的复杂系统,包括生物圈、大气层、水圈和土壤圈,作为一个进化的系统紧密结合在一起。这个假说认为,这个被称为盖亚的系统作为一个整体,寻求一个适合当代生命的物理和化学环境。<br />
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Biologists and Earth scientists usually view the factors that stabilize the characteristics of a period as an undirected [[emergent property]] or [[entelechy]] of the system; as each individual species pursues its own self-interest, for example, their combined actiYons may have counterbalancing effects on environmental change. Opponents of this view sometimes reference examples of events that resulted in dramatic change rather than stable equilibrium, such as the conversion of the Earth's atmosphere from a [[reducing environment]] to an [[oxygen]]-rich one at the end of the [[Archean|Archaean]] and the beginning of the [[Proterozoic]] periods.<br />
生物学家和地球科学家通常将稳定一个时期特征的因素视为系统的一个无方向的[[涌现属性]]或[[有目的行为]];例如,由于每个物种都追求自身利益,它们的联合行动可能对环境变化产生抵消作用。反对这一观点的人有时会举出一些事件的例子,这些事件导致了巨大的变化,而不是稳定的平衡,例如在[[太古宙|太古代]]末期和[[元古代]]时期开始时,地球大气从[[还原环境]]转变为富含[[氧气]]。 <br />
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Gaia evolves through a cybernetic feedback system operated unconsciously by the biota, leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially microorganisms, with inorganic elements. These processes establish a global control system that regulates Earth's surface temperature, atmosphere composition and ocean salinity, powered by the global thermodynamic disequilibrium state of the Earth system.<!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
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盖亚通过一个由生物群无意识操作的控制论反馈系统进化,在一个完全的内稳态中达成可居住条件的广泛稳定。地球表面的许多过程对生命的条件至关重要,这些过程依赖于生命形式,特别是微生物与无机元素的相互作用。这些过程建立了一个全球控制系统,由地球系统的全球热力学不平衡状态提供动力,调节地球表面温度、大气成分和海洋盐度。<br />
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Less accepted versions of the hypothesis claim that changes in the biosphere are brought about through the [[Superorganism|coordination of living organisms]] and maintain those conditions through [[homeostasis]]. In some versions of [[Gaia philosophy]], all lifeforms are considered part of one single living planetary being called ''Gaia''. In this view, the atmosphere, the seas and the terrestrial crust would be results of interventions carried out by Gaia through the [[Coevolution|coevolving]] diversity of living organisms.<br />
不太被接受的假说声称生物圈的变化是通过[[超级有机体|生物体的协调]]来实现的,并通过[[内稳态]]来维持这些条件。在一些版本的[[盖亚哲学]]中,所有的生命形式都被认为是一个被称为“盖亚”的生命行星的一部分。在这种观点下,大气、海洋和地壳将是盖亚通过生物多样性进行干预的结果。 <br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of biogeochemistry, and it is being investigated also in other fields like Earth system science. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<br />
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以前在生物地球化学领域已经观察到受生命形式影响的行星内稳态的存在,而且在地球系统科学等其他领域也在研究这一现象。盖亚假说的原创性依赖于这样一种评估: 即使地球或外部事件威胁到这种平衡,这种平衡也是为了保持生命的最佳状态而积极追求的。<br />
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The Gaia hypothesis was an influence on the [[deep ecology]] movement.<ref>David Landis Barnhill, Roger S. Gottlieb (eds.), ''Deep Ecology and World Religions: New Essays on Sacred Ground'', SUNY Press, 2010, p. 32.</ref><br />
盖亚假说对[[深层生态学]]运动产生了影响 <br />
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==Details细节==<br />
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Rob Rohde's palaeotemperature graphs<br />
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罗布·罗德的古温度图<br />
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The Gaia hypothesis posits that the Earth is a self-regulating [[complex system]] involving the [[biosphere]], the [[Earth's atmosphere|atmosphere]], the [[hydrosphere]]s and the [[pedosphere]], tightly coupled as an evolving system. The hypothesis contends that this system as a whole, called Gaia, seeks a physical and chemical environment optimal for contemporary life.<ref name="vanishing255">Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 255. {{ISBN|978-0-465-01549-8}}</ref><br />
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盖亚假说假设地球是一个自我调节的[[复杂系统]],包括[[生物圈]]、[[地球大气|大气]]、[[水圈]]和[[土壤圈]],作为一个进化系统紧密耦合。该假说认为,这个系统作为一个整体,称为盖亚,寻求一个最适合当代生活的物理和化学环境 <br />
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Since life started on Earth, the energy provided by the Sun has increased by 25% to 30%; however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on Titan. research has suggested that "oxygen shocks" and reduced methane levels led, during the Huronian, Sturtian and Marinoan/Varanger Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre Phanerozoic biosphere to fully self-regulate.<br />
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自从地球上有生命以来,太阳提供的能量增加了25%到30%;然而,地球表面温度一直保持在适宜居住的水平上,达到了相当规律的高低边缘。洛夫洛克还假设,产甲烷菌在早期大气中产生了较高水平的甲烷,这与在石化烟雾中发现的观点相似,在某些方面与土卫六上的大气相似。研究表明,在休伦期、斯图尔特期和马里诺/瓦朗格冰期,“氧冲击”和甲烷含量降低导致世界几乎变成了一个坚实的“雪球”。这些时代是前显生宙生物圈完全自我调节能力的证据。<br />
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Gaia evolves through a [[Cybernetic#In biology|cybernetic]] [[feedback]] system operated unconsciously by the [[biota (ecology)|biota]], leading to broad stabilization of the conditions of habitability in a full homeostasis. Many processes in the Earth's surface essential for the conditions of life depend on the interaction of living forms, especially [[microorganisms]], with inorganic elements. These processes establish a global control system that regulates Earth's [[Sea surface temperature|surface temperature]], [[atmosphere composition]] and [[ocean]] [[salinity]], powered by the global thermodynamic disequilibrium state of the Earth system.<ref>Kleidon, Axel. ''How does the earth system generate and maintain thermodynamic disequilibrium and what does it imply for the future of the planet?''. Article submitted to the ''Philosophical Transactions of the Royal Society'' on Thu, 10 Mar 2011</ref><!-- Article submitted to Royal Society is not a valid reference. This must be replaced by actual article citation if accepted, or an alternative reference --><br />
盖亚通过一个[[控制论|生物学|控制论]][[反馈]]系统在[[生物群(生态学)|生物群]]的无意识运作中进化,导致在完全的内稳态中可居住条件的广泛稳定。地球表面对生命条件至关重要的许多过程都依赖于生物,特别是[微生物]与无机元素的相互作用。这些过程建立了一个全球控制系统,调节地球的[[海表温度|表面温度]]、[[大气组成]]和[[海洋]][[盐度]],其动力来自地球系统的全球热力学不平衡状态。<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
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说明了处理温室气体CO2在维持地球温度在可居住范围内起着关键作用。<br />
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The existence of a planetary homeostasis influenced by living forms had been observed previously in the field of [[biogeochemistry]], and it is being investigated also in other fields like [[Earth system science]]. The originality of the Gaia hypothesis relies on the assessment that such homeostatic balance is actively pursued with the goal of keeping the optimal conditions for life, even when terrestrial or external events menace them.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 179. {{ISBN|978-0-465-01549-8}}</ref><br />
受生命形式影响的行星内稳态的存在,以前在[[生物地球化学]]领域就已被观察到,而且在其他领域,如[[地球系统科学]]也在研究中。盖亚假说的独创性依赖于这样一种评估,即积极追求这种体内平衡,以保持生命的最佳状态,即使是在地球或外部事件威胁它们的时候。<br />
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The CLAW hypothesis, inspired by the Gaia hypothesis, proposes a feedback loop that operates between ocean ecosystems and the Earth's climate. The hypothesis specifically proposes that particular phytoplankton that produce dimethyl sulfide are responsive to variations in climate forcing, and that these responses lead to a negative feedback loop that acts to stabilise the temperature of the Earth's atmosphere.<br />
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受盖亚假说的启发,CLAW 假说提出了一个在海洋生态系统和地球气候之间运行的反馈回路。该假说特别提出,产生二甲硫醚的浮游植物对气候强迫的变化有反应,这些反应导致了一个负反馈循环,稳定了地球大气的温度。<br />
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===Regulation of global surface temperature地球表面温度的调控===<br />
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[[File:All palaeotemps.png|thumb|480px|Rob Rohde's palaeotemperature graphs]]<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of greenhouse gases may cause negative feedbacks in the environment to become positive feedback. Lovelock has stated that this could bring an extremely accelerated global warming, but he has since stated the effects will likely occur more slowly.<br />
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目前,人口的增加及其活动对环境的影响,例如温室气体的增加,可能导致环境中的负反馈成为正反馈。洛夫洛克表示,这可能会极大地加速全球变暖,但他后来又表示,这种影响可能会发生得更慢。<br />
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{{See also|Paleoclimatology}}<br />
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Since life started on Earth, the energy provided by the [[Sun]] has increased by 25% to 30%;<ref name="Owen1979">{{cite journal | author = Owen, T. | author2 = Cess, R.D. | author3 = Ramanathan, V. | date = 1979 | title = Earth: An enhanced carbon dioxide greenhouse to compensate for reduced solar luminosity | journal = [[Nature (journal)|Nature]] | volume = 277 | pages = 640–2 | doi = 10.1038/277640a0 | issue=5698 | bibcode = 1979Natur.277..640O | ref = harv }}</ref> however, the surface temperature of the planet has remained within the levels of habitability, reaching quite regular low and high margins. Lovelock has also hypothesised that methanogens produced elevated levels of methane in the early atmosphere, giving a view similar to that found in petrochemical smog, similar in some respects to the atmosphere on [[Titan (moon)|Titan]].<ref name="agesofgaia"/> This, he suggests tended to screen out ultraviolet until the formation of the ozone screen, maintaining a degree of homeostasis. However, the [[Snowball Earth]]<ref>Hoffman, P.F. 2001. [http://www.snowballearth.org ''Snowball Earth theory'']</ref> research has suggested that "oxygen shocks" and reduced methane levels led, during the [[Huronian]], [[Sturtian]] and [[Marinoan]]/[[Cryogenian|Varanger]] Ice Ages, to a world that very nearly became a solid "snowball". These epochs are evidence against the ability of the pre [[Phanerozoic]] biosphere to fully self-regulate.<br />
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Plots from a standard black and white [[Daisyworld simulation]]<br />
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从一个标准的黑白图[[雏菊世界模拟]]<br />
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Processing of the greenhouse gas CO<sub>2</sub>, explained below, plays a critical role in the maintenance of the Earth temperature within the limits of habitability.<br />
说明了在温室气体维持低于临界温度的过程中,CO2起着至关重要的作用。 <br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic group selection and cooperation between organisms, James Lovelock and Andrew Watson developed a mathematical model, Daisyworld, in which ecological competition underpinned planetary temperature regulation.<br />
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有人批评盖亚假说似乎需要不切实际的群体选择和有机体之间的合作,为了回应这种批评,James Lovelock 和 Andrew Watson建立了一个数学模型---- 雏菊世界,其中生态竞争支撑着地。<br />
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The [[CLAW hypothesis]], inspired by the Gaia hypothesis, proposes a [[feedback|feedback loop]] that operates between [[ocean]] [[ecosystem]]s and the [[Earth]]'s [[climate]].<ref name="CLAW87">{{cite journal |doi=10.1038/326655a0 |author=[[Robert Jay Charlson|Charlson, R. J.]], [[James Lovelock|Lovelock, J. E]], Andreae, M. O. and Warren, S. G. |title=Oceanic phytoplankton, atmospheric sulphur, cloud albedo and climate |journal=Nature |volume=326 |issue=6114 |pages=655–661 |date=1987 |bibcode=1987Natur.326..655C |ref=harv }}</ref> The [[hypothesis]] specifically proposes that particular [[phytoplankton]] that produce [[dimethyl sulfide]] are responsive to variations in [[climate forcing]], and that these responses lead to a [[negative feedback|negative feedback loop]] that acts to stabilise the [[temperature]] of the [[Earth's atmosphere]].<br />
受到盖亚假说启发的[[爪假说]]提出了一个在[[海洋]][[生态系统]]和[[地球]]的[[气候]]之间运行的[[反馈|反馈回路]]。<br />
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Daisyworld examines the energy budget of a planet populated by two different types of plants, black daisies and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the albedo of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
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《雏菊世界》调查了一个星球的能量预算,这个星球上生长着两种不同的植物,黑色雏菊和白色雏菊,这两种植物被认为占据了星球表面的很大一部分。雏菊的颜色影响了地球的反照率,黑色的雏菊吸收更多的光线,使地球变暖,而白色的雏菊则反射更多的光线,使地球变冷。人们认为黑色雏菊在较低的温度下生长和繁殖最好,而白色雏菊则被认为在较高的温度下生长最好。当温度上升到接近白色雏菊所喜欢的温度时,白色雏菊伸展出黑色雏菊,导致更大比例的白色表面,更多的阳光被反射,减少热量输入,最终使地球降温。相反,随着气温的下降,黑色雏菊长出了白色雏菊,吸收了更多的阳光,使地球变暖。因此,温度会收敛到与植物繁殖率相等的值。<br />
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Currently the increase in human population and the environmental impact of their activities, such as the multiplication of [[greenhouse gases]] may cause [[negative feedback]]s in the environment to become [[positive feedback]]. Lovelock has stated that this could bring an [[James Lovelock#The revenge of Gaia|extremely accelerated global warming]],<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, {{ISBN|978-0-465-01549-8}}</ref> but he has since stated the effects will likely occur more slowly.<ref>Lovelock J., NBC News. [http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite Link] Published 23 April 2012, accessed 22 August 2012. {{Webarchive|url=https://web.archive.org/web/20120913163635/http://worldnews.nbcnews.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change?lite |date=13 September 2012 }}</ref><br />
目前,人口的增加及其活动对环境的影响,如[[温室气体]]的倍增,可能导致环境中的[[负反馈]]变成[[正反馈]]。洛夫洛克曾表示,这可能会带来一场【【James Loveloc【《盖亚的复仇』极度加速的全球变暖】】 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this negative feedback due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
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洛夫洛克和沃森指出,在有限的条件下,如果太阳的能量输出发生变化,由于竞争而产生的负反馈可以将地球温度稳定在支持生命的数值上,而没有生命的地球则会表现出巨大的温度波动。白色和黑色雏菊的百分比会不断变化,以保持植物繁殖率相等的温度值,使两种生命形式都能茁壮成长。<br />
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====Daisyworld simulations雏菊世界模拟====<br />
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[[File:StandardDaisyWorldRun2color.gif|thumb|280px|Plots from a standard black and white [[Daisyworld]] simulation]]<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<br />
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有人认为,这些结果是可以预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的答案。<br />
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{{Main|Daisyworld}}<br />
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In response to the criticism that the Gaia hypothesis seemingly required unrealistic [[group selection]] and [[Cooperation (evolution)|cooperation]] between organisms, James Lovelock and [[Andrew Watson (scientist)|Andrew Watson]] developed a mathematical model, [[Daisyworld]], in which [[Competition (biology)|ecological competition]] underpinned planetary temperature regulation.<ref name="daisyworld">{{cite journal<br />
有人批评盖亚假说似乎需要有机体之间不切实际的[[群体选择]]和[[合作(进化)|合作]],詹姆斯·洛夫洛克和[[安德鲁·沃森(科学家)|安德鲁·沃森]]开发了一个数学模型,[[雏菊世界]],其中[[竞争(生物学)|生态竞争]]为基础行星温度调节。 <br />
|date = 1983<br />
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Ocean salinity has been constant at about 3.5% for a very long time. Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested that salinity may also be strongly influenced by seawater circulation through hot basaltic rocks, and emerging as hot water vents on mid-ocean ridges. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<br />
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长期以来,海洋盐度一直保持在3.5% 左右。海洋环境中盐度的稳定性很重要,因为大多数细胞需要相当恒定的盐度,一般不能容忍超过5% 的盐度值。恒定的海洋盐度是一个长期存在的秘密,因为没有任何方法可以抵消来自河流的盐的流入。最近有人提出,盐度也可能受到穿过炽热玄武岩的海水循环的强烈影响,并在洋中脊上出现热水喷口。然而,海水的组成离平衡还很远,如果没有有机过程的影响,很难解释这一事实。有一种解释认为,地球历史上盐原的形成是原因之一。据推测,这些是由细菌菌落产生的,它们在生命过程中固定离子和重金属。<br />
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|title = Biological homeostasis of the global environment: the parable of Daisyworld<br />
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|journal = Tellus<br />
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|volume = 35B<br />
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Vostok, Antarctica research station. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
沃斯托克,南极洲研究站。当前期间在左边。<!--基于此图表的GIMP-FX版本的非源材料。现在的版本是正确的,原版的。必须删除这句话:请注意,当前CO2水平超过390ppm,远高于过去40万年来的任何时候-->] <br />
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|pages = 286–9<br />
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|bibcode = 1983TellB..35..284W<br />
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|doi = 10.1111/j.1600-0889.1983.tb00031.x<br />
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The Gaia hypothesis states that the Earth's atmospheric composition is kept at a dynamically steady state by the presence of life. The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than noble gases present in the atmosphere are either made by organisms or processed by them.<br />
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盖亚假说认为,地球的大气组成是由于生命的存在而保持在动态稳定的状态。大气成分提供了现代生活已经适应的条件。大气中除惰性气体以外的所有大气气体,要么是由生物体产生的,要么是由生物体加工的。<br />
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|last1 = Watson | first1= A.J. | last2= Lovelock | first2= J.E<br />
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|issue = 4<br />
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The stability of the atmosphere in Earth is not a consequence of chemical equilibrium. Oxygen is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the Great Oxygenation Event. Since the start of the Cambrian period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume. Traces of methane (at an amount of 100,000 tonnes produced per year) should not exist, as methane is combustible in an oxygen atmosphere.<br />
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地球大气层的稳定性不是化学平衡的结果。氧是一种活性化合物,最终会与地球大气层和地壳中的气体和矿物质结合。在大氧化事件空间站开始之前,大约5000万年左右,氧气才开始在大气中少量地持续存在。自寒武纪以来,大气中氧浓度一直在大气体积的15% 至35% 之间波动。微量的甲烷(每年产生100,000吨)不应该存在,因为甲烷在氧气氛中是可燃的。<br />
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|ref = harv<br />
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}}</ref><br />
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Dry air in the atmosphere of Earth contains roughly (by volume) 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases including methane. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. <br />
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地球大气层中的干燥空气大致(按体积计算)含有78.09% 的氮气、20.95% 的氧气、0.93% 的氩气、0.039% 的二氧化碳以及少量的其他气体,包括甲烷。洛夫洛克最初推测,高于25% 的氧气浓度会增加森林大火和森林大火的发生频率。最近在石炭纪和白垩纪煤系地质时期,当O2确实超过了25%时,火成木炭的研究结果支持了 Lovelock 的论点。<br />
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Daisyworld examines the [[Earth's energy budget|energy budget]] of a [[planet]] populated by two different types of plants, black [[Asteraceae|daisies]] and white daisies, which are assumed to occupy a significant portion of the surface. The colour of the daisies influences the [[albedo]] of the planet such that black daisies absorb more light and warm the planet, while white daisies reflect more light and cool the planet. The black daisies are assumed to grow and reproduce best at a lower temperature, while the white daisies are assumed to thrive best at a higher temperature. As the temperature rises closer to the value the white daisies like, the white daisies outreproduce the black daisies, leading to a larger percentage of white surface, and more sunlight is reflected, reducing the heat input and eventually cooling the planet. Conversely, as the temperature falls, the black daisies outreproduce the white daisies, absorbing more sunlight and warming the planet. The temperature will thus converge to the value at which the reproductive rates of the plants are equal.<br />
Daisyworld研究了[[地球的能源预算|能源预算]]的[[地球的能源预算]]居住着两种不同类型的植物,黑色的[[菊科的雏菊]]和白色的雏菊,这两种植物被认为占据了地表的很大一部分。雏菊的颜色影响着这个星球的[反照率],因此黑色雏菊吸收更多的光并温暖地球,而白色雏菊则反射更多的光并使地球降温。黑雏菊在较低温度下生长繁殖最好,而白雏菊在较高温度下生长繁殖最好。当温度上升到接近白色雏菊的数值时,白色雏菊的繁殖能力超过了黑色雏菊,导致白色表面的比例增大,更多的阳光被反射,减少了热量输入,最终使地球变冷。相反,随着温度的下降,黑雏菊的繁殖能力超过了白雏菊,吸收了更多的阳光,使地球变暖。因此,温度将收敛到植物繁殖率相等的值。 <br />
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Lovelock and Watson showed that, over a limited range of conditions, this [[negative feedback]] due to competition can stabilize the planet's temperature at a value which supports life, if the energy output of the Sun changes, while a planet without life would show wide temperature swings. The percentage of white and black daisies will continually change to keep the temperature at the value at which the plants' reproductive rates are equal, allowing both life forms to thrive.<br />
Lovelock和Watson表明,在有限的条件范围内,如果太阳的能量输出发生变化,由于竞争而产生的[[负面反馈]]可以将地球的温度稳定在支持生命的值上,而没有生命的行星则会出现大范围的温度波动。白雏菊和黑雏菊的比例会不断变化,以使温度保持在植物繁殖率相等的值,从而使两种生命形式都能茁壮成长。 <br />
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Gaia scientists see the participation of living organisms in the carbon cycle as one of the complex processes that maintain conditions suitable for life. The only significant natural source of atmospheric carbon dioxide (CO<sub>2</sub>) is volcanic activity, while the only significant removal is through the precipitation of carbonate rocks. Carbon precipitation, solution and fixation are influenced by the bacteria and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
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盖亚的科学家们把生物体参与碳循环看作是维持适合生命条件的复杂过程之一。火山活动是大气中二氧化碳的唯一重要自然来源,而碳酸盐岩的沉淀是大气中二氧化碳唯一重要的去除途径。碳沉淀、溶解和固定受到土壤中细菌和植物根系的影响,这些细菌和植物根系可以改善气体循环,或者在珊瑚礁中,碳酸钙以固体的形式沉积在海底。碳酸钙被活的有机体用来制造含碳的试验和外壳。一旦死亡,生物体的外壳就会沉到海底,在那里它们产生白垩和石灰石的沉淀物。<br />
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It has been suggested that the results were predictable because Lovelock and Watson selected examples that produced the responses they desired.<ref>{{cite journal | doi = 10.1023/A:1023494111532 | date = 2003 | last1 = Kirchner | first1 = James W. | journal = Climatic Change | volume = 58 |issue=1–2| pages = 21–45 |title=The Gaia Hypothesis: Conjectures and Refutations | ref = harv}}</ref><br />
有人认为,结果是可预测的,因为洛夫洛克和沃森选择的例子产生了他们想要的反应。 <br />
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One of these organisms is Emiliania huxleyi, an abundant coccolithophore algae which also has a role in the formation of clouds. CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants. Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean algal blooms are also increasing.<br />
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其中一种是赫氏圆石藻,这是一种数量丰富的颗石藻类,也参与了云的形成。CO < sub > 2 </sub > 过量通过增加球石氟化物的寿命来补偿,增加了锁定在海底的 CO < sub > 2 </sub > 的数量。球石粉会增加云量,从而控制地表温度,有助于降低整个地球的温度,有利于地球上植物所必需的降水。近年来,大气中 CO < < sub > 2 </sub > 浓度有所增加,有证据表明,海洋藻华的浓度也在增加。<br />
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===Regulation of oceanic salinity海洋盐度调节 ===<br />
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Lichen and other organisms accelerate the weathering of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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地衣和其他生物加速了岩石表面的风化,而岩石在土壤中的分解也加快了,这要归功于根、真菌、细菌和地下动物的活动。因此,二氧化碳从大气层流向土壤的过程是在生物的帮助下进行调节的。当大气中 CO2水平升高时,温度升高,植物生长。这种生长会增加植物对二氧化碳的消耗,植物会将二氧化碳处理到土壤中,从大气中排出。<br />
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Ocean [[salinity]] has been constant at about 3.5% for a very long time.<ref name=":0">{{Cite book|title=The Introduction to Ocean Sciences|last=Segar|first=Douglas|publisher=Library of Congress|year=2012|isbn=978-0-9857859-0-1|location=http://www.reefimages.com/oceans/SegarOcean3Chap05.pdf|pages=Chapter 5 3rd Edition|quote=|via=}}</ref> Salinity stability in oceanic environments is important as most cells require a rather constant salinity and do not generally tolerate values above 5%. The constant ocean salinity was a long-standing mystery, because no process counterbalancing the salt influx from rivers was known. Recently it was suggested<ref name="Gorham19912">{{cite journal|last=Gorham|first=Eville|date=1 January 1991|title=Biogeochemistry: its origins and development|journal=Biogeochemistry|publisher=Kluwer Academic|volume=13|issue=3|pages=199–239|doi=10.1007/BF00002942|issn=1573-515X|ref=harv}}</ref> that salinity may also be strongly influenced by [[seawater]] circulation through hot [[basalt]]ic rocks, and emerging as hot water vents on [[mid-ocean ridge]]s. However, the composition of seawater is far from equilibrium, and it is difficult to explain this fact without the influence of organic processes. One suggested explanation lies in the formation of salt plains throughout Earth's history. It is hypothesized that these are created by bacterial colonies that fix ions and heavy metals during their life processes.<ref name=":0" /><br />
在很长一段时间内,海洋盐度一直保持在3.5%左右。[23]海洋环境中的盐度稳定性非常重要,因为大多数细胞需要相当恒定的盐度,并且通常不能容忍超过5%的盐度值。恒定的海洋盐度是一个长期存在的谜团,因为没有任何过程可以抵消河流中的盐流入。最近有人认为[24]海水通过热玄武质岩石时也会受到海水循环的强烈影响,并在大洋中脊上出现热水喷口。然而,海水的组成远未达到平衡,如果没有有机过程的影响,很难解释这一事实。一个建议的解释是,在整个地球的历史中,盐平原的形成。据推测,这些细菌是由在生命过程中固定离子和重金属的菌落产生的<br />
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In the biogeochemical processes of Earth, sources and sinks are the movement of elements. The composition of salt ions within our oceans and seas is: sodium (Na<sup>+</sup>), chlorine (Cl<sup>−</sup>), sulfate (SO<sub>4</sub><sup>2−</sup>), magnesium (Mg<sup>2+</sup>), calcium (Ca<sup>2+</sup>) and potassium (K<sup>+</sup>). The elements that comprise salinity do not readily change and are a conservative property of seawater.<ref name=":0" /> There are many mechanisms that change salinity from a particulate form to a dissolved form and back. The known sources of sodium i.e. salts are when weathering, erosion, and dissolution of rocks are transported into rivers and deposited into the oceans.<br />
在地球的生物地球化学过程中,源和汇是元素的运动。我们海洋中盐离子的组成是:钠(Na+)、氯(Cl-)、硫酸盐(SO42-)、镁(Mg2+)、钙(Ca2+)和钾(K+)。构成盐度的元素不易变化,是海水的一种保守属性。[23]有许多机制可以将盐度从颗粒形态改变为溶解形态,然后再返回。已知的钠(即盐)来源于岩石的风化、侵蚀和溶解作用被输送到河流中并沉积到海洋中。 <br />
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The [[Mediterranean Sea]] as being Gaia's kidney is found ([http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/ here]) by Kenneth J. Hsue, a correspondence author in 2001. The "[[desiccation]]" of the Mediterranean is the evidence of a functioning kidney. Earlier "kidney functions" were performed during the "[[Deposition (geology)|deposition]] of the [[Cretaceous]] ([[Atlantic Ocean|South Atlantic]]), [[Jurassic]] ([[Gulf of Mexico]]), [[Permian–Triassic extinction event|Permo-Triassic]] ([[Europe]]), [[Devonian]] ([[Canada]]), [[Cambrian]]/[[Precambrian]] ([[Gondwana]]) saline giants."<ref>{{Cite web|url=http://scimar.icm.csic.es/scimar/index.php/secId/6/IdArt/209/|title=Scientia Marina: List of Issues|last=http://www.webviva.com|first=Justino Martinez. Web Viva 2007|website=scimar.icm.csic.es|language=English|access-date=2017-02-04}}</ref><br />
地中海是盖亚的肾脏,由肯尼斯·J·休伊(KennethJ.Hsue)在2001年发现的。地中海的“干涸”是肾功能正常的证据。早期的“肾功能”是在“白垩纪(南大西洋)、侏罗纪(墨西哥湾)、二叠纪-三叠纪(欧洲)、泥盆纪(加拿大)、寒武纪/前寒武纪(冈瓦纳)盐沼沉积时期进行的。” <br />
[[Earthrise taken from Apollo 8 on December 24, 1968]]<br />
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[1968年12月24日阿波罗8号拍摄的地出]<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The mythical Gaia was the primal Greek goddess personifying the Earth, the Greek version of "Mother Nature" (from Ge = Earth, and Aia = <br />
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地球作为一个完整的整体,一个有生命的存在,这个观念有着悠久的传统。神话中的盖亚是拟人化地球的原始希腊女神,是希腊版本的“自然母亲”(来自 Ge = 地球,和 Aia = <br />
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===Regulation of oxygen in the atmosphere大气层的氧气调节===<br />
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PIE grandmother), or the Earth Mother. James Lovelock gave this name to his hypothesis after a suggestion from the novelist William Golding, who was living in the same village as Lovelock at the time (Bowerchalke, Wiltshire, UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry. Later, the naturalist and explorer Alexander von Humboldt recognized the coevolution of living organisms, climate, and Earth's crust. His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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派祖母,或地球母亲。詹姆斯·洛夫洛克根据小说家威廉·戈尔丁的建议给他的假设起了这个名字,他当时和洛夫洛克住在同一个村子里(英国威尔特郡鲍尔查尔克)。戈尔丁的建议是以Gea为基础的,Gea是希腊女神名字的另一种拼写,在地质学、地球物理和地球化学中,Gea是前缀。后来,博物学家和探险家亚历山大·冯·洪堡认识到生物、气候和地壳的共同进化。他的远见卓识的声明在西方没有被广泛接受,几十年后,盖亚假说受到了科学界同样类型的最初抵制。<br />
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[[File:Vostok 420ky 4curves insolation.jpg|thumb|280px|Levels of gases in the atmosphere in 420,000 years of ice core data from [[Vostok Station|Vostok, Antarctica research station]]. Current period is at the left. <!-- Unsourced material based on GIMP FX version of this chart. The current version here is correct, original. This verbiage must be removed: Note that current CO<sub>2</sub> levels are more than 390 ppm, far higher than at any time in the last 400,000 years -->]]<br />
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{{See also|Geological history of oxygen}}<br />
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Also in the turn to the 20th century Aldo Leopold, pioneer in the development of modern environmental ethics and in the movement for wilderness conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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同样在20世纪之交,现代环境伦理学发展的先驱、荒野保护运动的先驱奥尔多 · 利奥波德在他的生物中心或整体的土地伦理学中提出了一个有生命的地球。<br />
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The Gaia hypothesis states that the Earth's [[Atmospheric chemistry#Atmospheric composition|atmospheric composition]] is kept at a dynamically steady state by the presence of life.<ref>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, p. 163. {{ISBN|978-0-465-01549-8}}</ref> The atmospheric composition provides the conditions that contemporary life has adapted to. All the atmospheric gases other than [[noble gas]]es present in the atmosphere are either made by organisms or processed by them.<br />
盖亚假说指出,地球的大气成分由于生命的存在而保持在动态稳定的状态。大气中除惰性气体以外的所有大气气体都是由生物体制造或加工而成。<br />
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The stability of the atmosphere in Earth is not a consequence of [[chemical equilibrium]]. [[Oxygen]] is a reactive compound, and should eventually combine with gases and minerals of the Earth's atmosphere and crust. Oxygen only began to persist in the atmosphere in small quantities about 50 million years before the start of the [[Great Oxygenation Event]].<ref name=Anabar2007>{{Cite journal| last4 = Arnold| last6 = Creaser| last3 = Lyons| first1 = A. | first2 = Y.| last9 = Scott| last2 = Duan | first3 = T. | first4 = G.| last8 = Gordon | first5 = B. | first10 = J. | first6 = R.| last10 = Garvin | first7 = A.| last11 = Buick | first8 = G. | first11 = R. | first9 = C.| title = A whiff of oxygen before the great oxidation event?| journal = Science| volume = 317| issue = 5846| year = 2007| last7 = Kaufman| pages = 1903–1906| last5 = Kendall| pmid = 17901330| last1 = Anbar | doi = 10.1126/science.1140325|bibcode = 2007Sci...317.1903A }}</ref> Since the start of the [[Cambrian]] period, atmospheric oxygen concentrations have fluctuated between 15% and 35% of atmospheric volume.<ref name=Berner1999>{{Cite journal<br />
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Another influence for the Gaia hypothesis and the environmental movement in general came as a side effect of the Space Race between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph Earthrise taken by astronaut William Anders in 1968 during the Apollo 8 mission became, through the Overview Effect an early symbol for the global ecology movement.<br />
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盖亚假说和环境运动的另一个影响来自于苏联和美利坚合众国之间太空竞赛的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球作为一个整体的样子。1968年,宇航员威廉 · 安德斯在阿波罗8号任务期间拍摄的地出照片,通过总体效应成为全球生态运动的早期象征。<br />
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| pmid = 10500106<br />
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| date=Sep 1999 | last1 = Berner | first1 = R. A.<br />
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| title = Atmospheric oxygen over Phanerozoic time<br />
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[[James Lovelock, 2005]]<br />
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[ James Lovelock,2005]<br />
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| volume = 96<br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the Jet Propulsion Laboratory in California on methods of detecting life on Mars. The first paper to mention it was Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life, co-authored with C.E. Giffin. A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the Pic du Midi observatory, planets like Mars or Venus had atmospheres in chemical equilibrium. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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65年9月,洛夫洛克在加利福尼亚喷气推进实验室研究探测火星生命的方法时,开始定义由生物群落控制的自我调节地球的概念。第一篇提到它的论文是行星大气:与C.E.Giffin合著的与生命存在有关的成分和其他变化。一个主要的概念是,通过大气的化学成分可以在行星尺度上探测到生命。根据picdumidi天文台收集的数据,像火星或金星这样的行星,其大气层处于化学平衡状态。这种与地球大气的差异被认为是这些行星上没有生命的证据。 <br />
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| issue = 20<br />
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| pages = 10955–10957<br />
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Lovelock formulated the Gaia Hypothesis in journal articles in 1972 and 1974, and a popular book length version of the hypothesis, published in 1979 as The Quest for Gaia, began to attract scientific and critical attention.<br />
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洛夫洛克在1972年和1974年的期刊文章中提出了盖亚假说,并在1979年出版了一本畅销书,名为《寻找盖亚》 ,开始引起科学界和批判界的关注。<br />
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| journal = Proceedings of the National Academy of Sciences of the United States of America<br />
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Lovelock called it first the Earth feedback hypothesis, and it was a way to explain the fact that combinations of chemicals including oxygen and methane persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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洛夫洛克首先将其称为地球反馈假说,这是一种解释包括氧气和甲烷在内的化学物质在地球大气中保持稳定浓度的方法。洛夫洛克认为,在其他行星的大气层中探测这种组合,是一种相对可靠和廉价的探测生命的方法。<br />
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| doi = 10.1073/pnas.96.20.10955<br />
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[[Lynn Margulis]]<br />
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[琳 · 玛格丽丝]<br />
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|bibcode = 1999PNAS...9610955B }}</ref> Traces of [[Atmospheric methane|methane]] (at an amount of 100,000 tonnes produced per year)<ref name="Cicerone1988">{{cite journal |last1=Cicerone |first1=R.J. |last2=Oremland |first2=R.S. |date=1988 |title=Biogeochemical aspects of atmospheric methane |journal=Global Biogeochemical Cycles |volume=2 |issue=4 |pages=299–327 |url=//webfiles.uci.edu/setrumbo/public/Methane_papers/Cicerone_Global%20Biogeochem%20Cy_1988.pdf |doi=10.1029/GB002i004p00299 |bibcode=1988GBioC...2..299C}}</ref> should not exist, as methane is combustible in an oxygen atmosphere.<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<br />
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后来出现了其他关系,例如海洋生物产生的硫和碘的数量与陆地生物所需的数量大致相同,这些都支持了这一假说。<br />
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Dry air in the [[atmosphere of Earth]] contains roughly (by volume) 78.09% [[nitrogen]], 20.95% oxygen, 0.93% [[argon]], 0.039% [[Carbon dioxide in the Earth's atmosphere|carbon dioxide]], and small amounts of other gases including [[methane]]. Lovelock originally speculated that concentrations of oxygen above about 25% would increase the frequency of wildfires and conflagration of forests. Recent work on the findings of fire-caused charcoal in Carboniferous and Cretaceous coal measures, in geologic periods when O<sub>2</sub> did exceed 25%, has supported Lovelock's contention. {{citation needed|date=June 2012}}<br />
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[[地球大气]]中的干空气大约(按体积)包含78.09%[[氮]],20.95%的氧,0.93%[[氩]],0.039%[地球大气中的二氧化碳|二氧化碳]],以及少量其他气体,包括[[甲烷]]。洛夫洛克最初推测,氧气浓度超过25%会增加森林火灾和火灾的发生率。最近在石炭纪和白垩纪煤系中发现的由火引起的木炭的研究,在地质时期O<sub>2</sub>超过25%,支持了Lovelock的观点 <br />
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In 1971 microbiologist Dr. Lynn Margulis joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet. The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of eukaryotic organelles and her contributions to the endosymbiotic theory, nowadays accepted. Margulis dedicated the last of eight chapters in her book, The Symbiotic Planet, to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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1971年,微生物学家 Lynn Margulis 博士加入了 Lovelock 的行列,努力将最初的假设充实为科学证明的概念,贡献了她关于微生物如何影响大气层和地球表面不同层次的知识。这位美国生物学家也唤醒了科学界的批评,因为她倡导真核细胞器起源的理论,以及她对美国共生发源学会的贡献,现在被接受了。玛格丽丝在她的书《共生星球》中将最后八章献给了盖亚。然而,她反对对盖亚的广泛拟人化,并强调盖亚“不是一个有机体” ,而是“有机体之间相互作用的一个新兴属性”。她将盖亚定义为“组成地球表面一个巨大生态系统的一系列相互作用的生态系统”。句号”。这本书最令人难忘的“口号”实际上是由马古利斯的一个学生打趣说的: “从太空看,盖亚只是共生而已。”。<br />
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===Processing of CO<sub>2</sub>二氧化碳处理===<br />
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{{See also|Carbon cycle}}<br />
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James Lovelock called his first proposal the Gaia hypothesis but has also used the term Gaia theory. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments and provided a number of useful predictions. In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating. The principal sponsor was the National Audubon Society. Speakers included James Lovelock, George Wald, Mary Catherine Bateson, Lewis Thomas, John Todd, Donald Michael, Christopher Bird, Thomas Berry, David Abram, Michael Cohen, and William Fields. Some 500 people attended.<br />
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詹姆斯 · 洛夫洛克称他的第一个提议为盖亚假说,但也使用了盖亚理论这个术语。洛夫洛克说,最初的提法是基于观察,但仍然缺乏科学的解释。盖亚假说从那以后得到了一些科学实验的支持,并提供了一些有用的预测。事实上,更广泛的研究证明了最初的假设是错误的,在这个意义上,不是生命本身,而是整个地球系统在调节。主要赞助者是奥杜邦学会。讲者包括 James Lovelock、 George Wald、 Mary Catherine Bateson、 Lewis Thomas、 John Todd、 Donald Michael、 Christopher Bird、 Thomas Berry、 David Abram、 Michael Cohen 和 William Fields。大约有500人参加。<br />
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Gaia scientists see the participation of living organisms in the [[carbon cycle]] as one of the complex processes that maintain conditions suitable for life. The only significant natural source of [[Carbon dioxide in Earth's atmosphere|atmospheric carbon dioxide]] ([[Carbon dioxide|CO<sub>2</sub>]]) is [[volcanic activity]], while the only significant removal is through the precipitation of [[carbonate rocks]].<ref name="Karhu1996">{{cite journal | author = Karhu, J.A. | author2 = Holland, H.D. | date = 1 October 1996 | title = Carbon isotopes and the rise of atmospheric oxygen | journal = [[Geology (journal)|Geology]] | volume = 24 | issue = 10 | pages = 867–870 | doi = 10.1130/0091-7613(1996)024<0867:CIATRO>2.3.CO;2|bibcode = 1996Geo....24..867K | ref = harv}}</ref> Carbon precipitation, solution and [[Carbon fixation|fixation]] are influenced by the [[bacteria]] and plant roots in soils, where they improve gaseous circulation, or in coral reefs, where calcium carbonate is deposited as a solid on the sea floor. Calcium carbonate is used by living organisms to manufacture carbonaceous tests and shells. Once dead, the living organisms' shells fall to the bottom of the oceans where they generate deposits of chalk and limestone.<br />
盖亚的科学家认为,生物参与[[碳循环]是维持适宜生命条件的复杂过程之一。[[地球大气中的二氧化碳|大气二氧化碳]]([[二氧化碳| CO2]])的唯一重要自然来源是[[火山活动]],而唯一显著的清除是通过[[碳酸盐岩]]的沉淀,溶液和[[固碳|固碳]]受土壤中的[[细菌]]和植物根的影响,它们改善了气体循环,珊瑚礁中碳酸钙以固体形式沉积在海底。碳酸钙被生物用来制造含碳测试和贝壳。一旦死亡,这些生物的壳就会落到海底,在那里它们会产生白垩和石灰岩的沉积物。 <br />
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One of these organisms is ''[[Emiliania huxleyi]]'', an abundant [[coccolithophore]] [[algae]] which also has a role in the formation of [[cloud]]s.<ref name="Harding2006">{{cite book |author=Harding, Stephan |title=Animate Earth |publisher=Chelsea Green Publishing |date=2006 |pages=65 |isbn=978-1-933392-29-5 }}</ref> CO<sub>2</sub> excess is compensated by an increase of coccolithophoride life, increasing the amount of CO<sub>2</sub> locked in the ocean floor. Coccolithophorides increase the cloud cover, hence control the surface temperature, help cool the whole planet and favor precipitations necessary for terrestrial plants.{{citation needed|date=July 2015}} Lately the atmospheric CO<sub>2</sub> concentration has increased and there is some evidence that concentrations of ocean [[algal bloom]]s are also increasing.<ref>{{Cite web | date = 12 September 2007 | title = Interagency Report Says Harmful Algal Blooms Increasing | url = http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | url-status = dead | archiveurl = https://web.archive.org/web/20080209234239/http://www.publicaffairs.noaa.gov/releases2007/sep07/noaa07-r435.html | archivedate = 9 February 2008 }}</ref><br />
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In 1988, climatologist Stephen Schneider organised a conference of the American Geophysical Union. The first Chapman Conference on Gaia,<br />
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在1988年,气候学家史蒂芬·史奈德组织了一次美国美国地球物理联盟协会的会议。关于盖亚的第一次查普曼会议,<br />
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[[Lichen]] and other organisms accelerate the [[weathering]] of rocks in the surface, while the decomposition of rocks also happens faster in the soil, thanks to the activity of roots, fungi, bacteria and subterranean animals. The flow of carbon dioxide from the atmosphere to the soil is therefore regulated with the help of living beings. When CO<sub>2</sub> levels rise in the atmosphere the temperature increases and plants grow. This growth brings higher consumption of CO<sub>2</sub> by the plants, who process it into the soil, removing it from the atmosphere.<br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the Daisyworld Model (and its modifications, above) as evidence against most of these criticisms.<br />
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然而,洛夫洛克和其他支持盖亚理论的科学家确实试图反驳这样一种说法,即这种假设不科学,因为不可能通过控制实验来检验它。例如,针对盖亚是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修正,上文)作为反驳大多数这些批评的证据。<br />
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==History历史==<br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of teleologism ceased, following this conference.<br />
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洛夫洛克谨慎地提出了盖亚假说的一个版本,该假说没有声称盖亚有意或有意地在她的环境中维持生命赖以生存的复杂平衡。看起来,盖亚“故意”行为的说法只是他那本广受欢迎的书中的一个比喻性陈述,并不是字面意义上的理解。这种对盖亚假说的新陈述更能为科学界所接受。在这次会议之后,大多数关于目的论的指责都停止了。<br />
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===Precedents先例===<br />
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[[File:NASA-Apollo8-Dec24-Earthrise.jpg|thumb|''[[Earthrise]]'' taken from [[Apollo 8]] on December 24, 1968]]<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000, the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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到2000年6月23日在西班牙巴伦西亚举行关于盖亚假说的第二次查普曼会议时,情况发生了重大变化。与其讨论盖亚的目的论观点,或盖亚假说的“类型” ,不如将重点放在具体的机制上,通过这些机制,基本的短期内稳态在一个重要的进化的长期结构变化的框架内得以维持。<br />
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The idea of the Earth as an integrated whole, a living being, has a long tradition. The [[Gaia (mythology)|mythical Gaia]] was the primal Greek goddess personifying the [[Earth]], the Greek version of "[[Mother Nature]]" (from Ge = Earth, and Aia = <br />
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[[PIE]] grandmother), or the [[Earth Mother]]. James Lovelock gave this name to his hypothesis after a suggestion from the novelist [[William Golding]], who was living in the same village as Lovelock at the time ([[Bowerchalke]], [[Wiltshire]], UK). Golding's advice was based on Gea, an alternative spelling for the name of the Greek goddess, which is used as prefix in geology, geophysics and geochemistry.<ref name=vanish09 /> Golding later made reference to Gaia in his [[Nobel prize]] acceptance speech.<br />
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The major questions were:<br />
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主要的问题是:<br />
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In the eighteenth century, as [[geology]] consolidated as a modern science, [[James Hutton]] maintained that geological and biological processes are interlinked.<ref name=CapraWeb>{{cite book |author=Capra, Fritjof |title=The web of life: a new scientific understanding of living systems |publisher=Anchor Books |location=Garden City, N.Y |date=1996 |page=[https://archive.org/details/weboflifenewscie00capr/page/23 23] |isbn=978-0-385-47675-1 |url=https://archive.org/details/weboflifenewscie00capr/page/23 }}</ref> Later, the [[naturalist]] and explorer [[Alexander von Humboldt]] recognized the coevolution of living organisms, climate, and Earth's crust.<ref name=CapraWeb /> In the twentieth century, [[Vladimir Vernadsky]] formulated a theory of Earth's development that is now one of the foundations of ecology. Vernadsky was a Ukrainian [[geochemist]] and was one of the first scientists to recognize that the oxygen, nitrogen, and carbon dioxide in the Earth's atmosphere result from biological processes. During the 1920s he published works arguing that living organisms could reshape the planet as surely as any physical force. Vernadsky was a pioneer of the scientific bases for the environmental sciences.<ref>S.R. Weart, 2003, ''The Discovery of Global Warming'', Cambridge, Harvard Press</ref> His visionary pronouncements were not widely accepted in the West, and some decades later the Gaia hypothesis received the same type of initial resistance from the scientific community.<br />
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"How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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“被称为盖亚的全球生物地球化学/气候系统是如何及时发生变化的?它的历史是什么?盖亚能够在一个时间尺度上保持系统的稳定性,但是在更长的时间尺度上仍然经历矢量变化吗?如何利用地质记录来检验这些问题? ”<br />
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"What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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“盖亚的结构是什么?这些反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由在任何特定时间进行的学科研究务实地决定的,还是有一些部分应该被认为是最真实的,以了解盖亚随着时间的推移包含进化中的生物体?盖亚系统这些不同部分之间的反馈是什么? 对盖亚作为全球生态系统的结构和生命的生产力来说,物质的近乎封闭意味着什么? ”<br />
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Also in the turn to the 20th century [[Aldo Leopold]], pioneer in the development of modern [[environmental ethics]] and in the movement for [[wilderness]] conservation, suggested a living Earth in his biocentric or holistic ethics regarding land.<br />
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"How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
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“盖亚过程和现象的模型如何与现实相关,它们如何帮助解决和理解盖亚?雏菊世界的成果如何转移到现实世界?什么是“雏菊”的主要候选人?我们发现雏菊与否对盖亚理论重要吗?我们应该怎样寻找雏菊,我们应该加紧寻找吗?如何利用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖亚机制? ”<br />
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{{quotation|It is at least not impossible to regard the earth's parts—soil, mountains, rivers, atmosphere etc,—as organs or parts of organs of a coordinated whole, each part with its definite function. And if we could see this whole, as a whole, through a great period of time, we might perceive not only organs with coordinated functions, but possibly also that process of consumption as replacement which in biology we call metabolism, or growth. In such case we would have all the visible attributes of a living thing, which we do not realize to be such because it is too big, and its life processes too slow.| Stephan Harding | ''Animate Earth''.<ref>Harding, Stephan. ''Animate Earth Science, Intuition and Gaia''. Chelsea Green Publishing, 2006, p. 44. {{ISBN|1-933392-29-0}}</ref>}}<br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise entropy production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
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1997年,泰勒·沃尔克认为,盖安系统几乎不可避免地会产生,这是一种向远离平衡的稳态演化的结果,这种平衡状态使熵产生最大化,克莱顿(2004)同意这样的说法:“自稳态行为可以从与行星反照率相关的MEP状态中产生”;“……一个如盖亚假说所述,处于MEP状态的生物地球很可能导致地球系统在长时间尺度上的近稳态行为。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。<br />
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Another influence for the Gaia hypothesis and the [[environmental movement]] in general came as a side effect of the [[Space Race]] between the Soviet Union and the United States of America. During the 1960s, the first humans in space could see how the Earth looked as a whole. The photograph ''[[Earthrise]]'' taken by astronaut [[William Anders]] in 1968 during the [[Apollo 8]] mission became, through the [[Overview Effect]] an early symbol for the global ecology movement.<ref>[http://digitaljournalist.org/issue0309/lm11.html 100 Photographs that Changed the World by Life - The Digital Journalist]</ref><br />
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盖亚假说和[[环境运动]]的另一个总体影响来自苏联和美利坚合众国之间[[太空竞赛]]的副作用。在20世纪60年代,第一批进入太空的人类可以看到地球的整体面貌。1968年宇航员[[William Anders]]在[[Apollo 8]]任务期间拍摄的照片“[[地球升起]”,通过[[概述效果]]成为全球生态运动的早期标志<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<br />
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第四次关于盖亚假说的国际会议,由北弗吉尼亚地区公园管理局和其他机构主办,于2006年10月在弗吉尼亚州乔治梅森大学的阿灵顿校区举行。<br />
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===Formulation of the hypothesis假说形成===<br />
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[[File:James Lovelock in 2005.jpg|thumb|[[James Lovelock]], 2005]]<br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
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马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。Lynn Margulis是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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Lovelock started defining the idea of a self-regulating Earth controlled by the community of living organisms in September 1965, while working at the [[Jet Propulsion Laboratory]] in California on methods of detecting [[life on Mars (planet)|life on Mars]].<ref name="Lovelock1965">{{cite journal | author = Lovelock, J.E. | date = 1965 | title = A physical basis for life detection experiments | journal = [[Nature (journal)|Nature]] | volume = 207 | issue = 7 | pages = 568–570 | doi = 10.1038/207568a0 | pmid=5883628|bibcode = 1965Natur.207..568L | ref = harv}}</ref><ref>{{Cite web |url=http://www.jameslovelock.org/page4.html |title=Geophysiology |access-date=2007-05-05 |archive-url=https://web.archive.org/web/20070506073502/http://www.jameslovelock.org/page4.html |archive-date=2007-05-06 |url-status=dead }}</ref> The first paper to mention it was ''Planetary Atmospheres: Compositional and other Changes Associated with the Presence of Life'', co-authored with C.E. Giffin.<ref>{{cite journal | author1 = Lovelock, J.E. | author2 = Giffin, C.E. | date = 1969 | title = Planetary Atmospheres: Compositional and other changes associated with the presence of Life | journal = Advances in the Astronautical Sciences | volume = 25 | pages = 179–193 | isbn = 978-0-87703-028-7 | ref = harv}}</ref> A main concept was that life could be detected in a planetary scale by the chemical composition of the atmosphere. According to the data gathered by the [[Pic du Midi de Bigorre|Pic du Midi observatory]], planets like Mars or Venus had atmospheres in [[chemical equilibrium]]. This difference with the Earth atmosphere was considered to be a proof that there was no life in these planets.<br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
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这次会议将盖亚假说作为一种科学和隐喻的手段,来理解我们如何开始解决21世纪的问题,如气候变化和持续的环境破坏。<br />
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Lovelock formulated the ''Gaia Hypothesis'' in journal articles in 1972<ref name="J1972">{{cite journal | author = J. E. Lovelock | title = Gaia as seen through the atmosphere | date = 1972 | journal = [[Atmospheric Environment]] | volume = 6 | issue = 8 | pages = 579–580 | doi = 10.1016/0004-6981(72)90076-5 | ref = harv|bibcode = 1972AtmEn...6..579L }}</ref> and 1974,<ref name="lovelock1974" /> followed by a popularizing 1979 book ''Gaia: A new look at life on Earth''. An article in the ''[[New Scientist]]'' of February 6, 1975,<ref>Lovelock, John and Sidney Epton, (February 8, 1975). "The quest for Gaia". [https://books.google.com/books?id=pnV6UYEkU4YC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false New Scientist], p. 304.</ref> and a popular book length version of the hypothesis, published in 1979 as ''The Quest for Gaia'', began to attract scientific and critical attention.<br />
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Lovelock called it first the Earth feedback hypothesis,<ref name="Lovelock01">{{harvnb|Lovelock, James|2001}}</ref> and it was a way to explain the fact that combinations of chemicals including [[oxygen]] and [[methane]] persist in stable concentrations in the atmosphere of the Earth. Lovelock suggested detecting such combinations in other planets' atmospheres as a relatively reliable and cheap way to detect life.<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as Ford Doolittle, Richard Dawkins and Stephen Jay Gould. Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists, He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as autopoietic or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole. With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<br />
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在最初几乎没有引起科学家的注意之后(从1969年到1977年) ,有一段时间,最初的盖亚假说受到了一些科学家的批评,如福特杜利特,理查德道金斯和史蒂芬·古尔德。洛夫洛克说,因为他的假说是以一位希腊女神的名字命名的,并得到许多非科学家的拥护,他想知道实现自我调节体内平衡的实际机制。在为盖亚辩护时,戴维•阿布拉姆认为,古尔德忽视了一个事实,即“机制”本身就是一个隐喻——尽管这个隐喻极其常见,而且往往不为人所知——这个隐喻让我们把自然和生命系统看作是由外部组织和建造的机器(而不是自动生成或自组织现象)。根据阿布拉姆的说法,机械隐喻使我们忽略了生命实体的活跃性或代表性,而盖亚假说的有机隐喻强调了生物群和整个生物圈的活跃性。关于盖亚的因果关系,洛夫洛克认为没有单一的机制是负责任的,各种已知机制之间的联系可能永远不会被人知道,这在生物学和生态学的其他领域是理所当然地被接受的,并且由于其他原因,特定的敌意是保留给他自己的假设的。<br />
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[[File:Lynn Margulis.jpg|thumb|left|[[Lynn Margulis]]]]<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of greedy reductionism in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<br />
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除了澄清他的语言和理解什么是生命形式,洛夫洛克自己把大部分的批评归因于他的批评者缺乏对非线性数学的理解,以及贪婪还原主义的线性化形式,在这种形式中,所有事件都必须立即归因于事件发生之前的特定原因。他还表示,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,以及一些自我调节现象可能无法在数学上解释。<br />
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Later, other relationships such as sea creatures producing sulfur and iodine in approximately the same quantities as required by land creatures emerged and helped bolster the hypothesis.<ref>{{cite journal | first1=W.D. | last1=Hamilton | first2=T.M. | last2=Lenton | title=Spora and Gaia: how microbes fly with their clouds | journal=Ethology Ecology & Evolution | volume=10 | pages=1–16 | date=1998 | issue=1 | url=http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | format=PDF | doi=10.1080/08927014.1998.9522867 | ref=harv | url-status=dead | archiveurl=https://web.archive.org/web/20110723055017/http://ejour-fup.unifi.it/index.php/eee/article/viewFile/787/733 | archivedate=2011-07-23 }}</ref><br />
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Evolutionary biologist W. D. Hamilton called the concept of Gaia Copernican, adding that it would take another Newton to explain how Gaian self-regulation takes place through Darwinian natural selection. More recently Ford Doolittle building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis. <br />
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进化生物学家W.D.Hamilton称盖亚为哥白尼的概念,并补充说,需要另一个牛顿来解释盖亚的自我调节是如何通过达尔文的自然选择发生的。最近,Ford Doolittle在他和Inkpen的ITSNTS(这是歌手而不是歌曲)的建议中提出,差异持续性可以在自然选择进化中起到与差异生殖相似的作用,从而为自然选择理论和盖亚假说之间提供了一种可能的调和。 <br />
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In 1971 [[microbiologist]] Dr. [[Lynn Margulis]] joined Lovelock in the effort of fleshing out the initial hypothesis into scientifically proven concepts, contributing her knowledge about how microbes affect the atmosphere and the different layers in the surface of the planet.<ref name="Turney, Jon 2003">{{cite book |author=Turney, Jon |title=Lovelock and Gaia: Signs of Life |publisher=Icon Books |location=UK |date=2003 |isbn=978-1-84046-458-0 |url-access=registration |url=https://archive.org/details/lovelockgaiasign0000turn }}</ref> The American biologist had also awakened criticism from the scientific community with her advocacy of the theory on the origin of [[eukaryote|eukaryotic]] [[organelle]]s and her contributions to the [[endosymbiotic theory]], nowadays accepted. Margulis dedicated the last of eight chapters in her book, ''The Symbiotic Planet'', to Gaia. However, she objected to the widespread personification of Gaia and stressed that Gaia is "not an organism", but "an emergent property of interaction among organisms". She defined Gaia as "the series of interacting ecosystems that compose a single huge ecosystem at the Earth's surface. Period". The book's most memorable "slogan" was actually quipped by a student of Margulis': "Gaia is just symbiosis as seen from space".<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal Climatic Change in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it. to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background" The CLAW hypothesis, In 2009 the Medea hypothesis was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<br />
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盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论据是,生命对环境产生了有害或不稳定的影响,而不是采取行动加以调节。为了“令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在背景下。”爪假说,2009年提出的美狄亚假说:生命对行星条件有高度有害的(生物杀灭)影响,与盖亚假说直接相反。 <br />
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James Lovelock called his first proposal the ''Gaia hypothesis'' but has also used the term ''Gaia theory''. Lovelock states that the initial formulation was based on observation, but still lacked a scientific explanation. The Gaia hypothesis has since been supported by a number of scientific experiments<ref name="J1990">{{cite journal | author = J. E. Lovelock | title = Hands up for the Gaia hypothesis | date = 1990 | journal = [[Nature (journal)|Nature]] | volume = 344 | issue = 6262 | pages = 100–2 | doi = 10.1038/344100a0|bibcode = 1990Natur.344..100L | ref = harv}}</ref> and provided a number of useful predictions.<ref name="Volk2003">{{cite book |author=Volk, Tyler |title=Gaia's Body: Toward a Physiology of Earth |publisher=[[MIT Press]] |location=Cambridge, Massachusetts |date=2003 |isbn=978-0-262-72042-7 }}</ref> In fact, wider research proved the original hypothesis wrong, in the sense that it is not life alone but the whole Earth system that does the regulating.<ref name="vanishing255"/><br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it". Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works". This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<br />
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2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚假说是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚假说的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新想法,并倡导一种整体的方法来研究地球”。在其他地方,他提出了自己的结论:“盖亚假说并不是我们这个世界如何运转的精确图像”。这种说法需要被理解为是指盖亚假说的“强”和“中”形式,生物群遵循的原则是使地球成为最佳(强度5)或有利于生命(强度4),或是作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚假说的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚假说的两种较弱的形式:共同进化的盖亚假说和有影响力的盖亚假说,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚假说”一词是没有用的,两种形式已经被自然选择和适应过程所接受和解释。 <br />
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===First Gaia conference第一次盖亚会议===<br />
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In 1985, the first public symposium on the Gaia hypothesis, ''Is The Earth A Living Organism?'' was held at [[University of Massachusetts Amherst]], August 1–6.<ref>{{cite news |last=Joseph |first=Lawrence E. |title=Britain's Whole Earth Guru |work=The New York Times Magazine |date=November 23, 1986 |url=https://www.nytimes.com/1986/11/23/magazine/britain-s-whole-earth-guru.html |accessdate=1 December 2013}}</ref> The principal sponsor was the [[National Audubon Society]]. Speakers included James Lovelock, [[George Wald]], [[Mary Catherine Bateson]], [[Lewis Thomas]], [[John Todd (Canadian biologist)|John Todd]], Donald Michael, [[Christopher Bird]], [[Thomas Berry]], [[David Abram]], [[Michael A. Cohen|Michael Cohen]], and William Fields. Some 500 people attended.<ref>Bunyard, Peter (1996), "Gaia in Action: Science of the Living Earth" (Floris Books)</ref><br />
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1985年,关于盖亚假说的第一次公开研讨会,“地球是一个活的有机体吗?”在马萨诸塞大学阿默斯特举行 <br />
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===Second Gaia conference第二次盖亚会议===<br />
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In 1988, [[climatology|climatologist]] [[Stephen Schneider]] organised a conference of the [[American Geophysical Union]]. The first Chapman Conference on Gaia,<ref name="ReferenceB"/> was held in San Diego, California on March 7, 1988.<br />
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1988年,climatology和Stephen Schneider组织了一次美国地球物理联合会会议。关于盖亚的第一次查普曼会议 <br />
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During the "philosophical foundations" session of the conference, [[David Abram]] spoke on the influence of metaphor in science, and of the Gaia hypothesis as offering a new and potentially game-changing metaphorics, while [[James Kirchner]] criticised the Gaia hypothesis for its imprecision. Kirchner claimed that Lovelock and Margulis had not presented one Gaia hypothesis, but four -<br />
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在会议的“哲学基础”会议上,David Abram谈到了隐喻在科学中的影响,盖亚假说提供了一种新的、可能改变游戏规则的隐喻,而James Kirchner则批评盖亚假说的不精确性。基什纳声称,洛夫洛克和马古利斯提出的盖亚假说不是一个,而是四个- <br />
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* [[Coevolution|CoEvolutionary]] Gaia: that life and the environment had evolved in a coupled way. Kirchner claimed that this was already accepted scientifically and was not new.<br />
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* [[Homeostatic]] Gaia: that life maintained the stability of the natural environment, and that this stability enabled life to continue to exist.<br />
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* [[Geophysics|Geophysical]] Gaia: that the Gaia hypothesis generated interest in geophysical cycles and therefore led to interesting new research in terrestrial geophysical dynamics.<br />
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* Optimising Gaia: that Gaia shaped the planet in a way that made it an optimal environment for life as a whole. Kirchner claimed that this was not testable and therefore was not scientific.<br />
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盖亚:生命和环境是以耦合的方式进化的。基什内尔声称,这已经被科学界接受,并不是什么新鲜事。 <br />
盖亚:生命维持着自然环境的稳定,这种稳定性使生命得以继续存在。 <br />
盖亚:盖亚假说引起了人们对地球物理周期的兴趣,因此导致了地球物理动力学中有趣的新研究。 <br />
优化盖亚:盖亚塑造了地球,使之成为整个生命的最佳环境。基什内尔声称,这是不可测试的,因此是不科学的。 <br />
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Of Homeostatic Gaia, Kirchner recognised two alternatives. "Weak Gaia" asserted that life tends to make the environment stable for the flourishing of all life. "Strong Gaia" according to Kirchner, asserted that life tends to make the environment stable, ''to enable'' the flourishing of all life. Strong Gaia, Kirchner claimed, was untestable and therefore not scientific.<ref>{{cite journal | bibcode=1989RvGeo..27..223K | doi = 10.1029/RG027i002p00223 | title=The Gaia hypothesis: Can it be tested? | date=1989 | last1=Kirchner | first1=James W. | journal=Reviews of Geophysics | volume=27 | issue=2 | pages=223 | ref=harv}}</ref><br />
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基什内尔发现了两种选择“软弱的盖亚”断言,为了所有生命的繁衍,生命往往会使环境变得稳定根据基什内尔的说法,“强大的盖亚”断言,生命趋向于使环境稳定,“使”所有生命繁荣昌盛。基什内尔声称,强大的盖亚是不稳定的,因此不科学。 <br />
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Lovelock and other Gaia-supporting scientists, however, did attempt to disprove the claim that the hypothesis is not scientific because it is impossible to test it by controlled experiment. For example, against the charge that Gaia was teleological, Lovelock and Andrew Watson offered the [[Daisyworld]] Model (and its modifications, above) as evidence against most of these criticisms.<ref name="daisyworld"/> Lovelock said that the Daisyworld model "demonstrates that self-regulation of the global environment can emerge from competition amongst types of life altering their local environment in different ways".<ref>{{cite journal | pmid=10968941 | date=2000 | last1=Lenton | first1=TM | last2=Lovelock | first2=JE | s2cid=5486128 | title=Daisyworld is Darwinian: Constraints on adaptation are important for planetary self-regulation | volume=206 | issue=1 | pages=109–14 | doi=10.1006/jtbi.2000.2105 | journal=Journal of Theoretical Biology | ref=harv}}</ref><br />
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然而,洛夫洛克和其他支持盖亚的科学家,确实试图反驳这种说法,即这个假设是不科学的,因为不可能通过受控实验来检验它。例如,针对盖亚是目的论的指控,洛夫洛克和安德鲁·沃森提出了雏菊世界模型(及其修改,洛夫洛克说,雏菊世界模型“证明了全球环境的自我调节可以通过不同方式改变当地环境的生活类型之间的竞争产生”。 <br />
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Lovelock was careful to present a version of the Gaia hypothesis that had no claim that Gaia intentionally or consciously maintained the complex balance in her environment that life needed to survive. It would appear that the claim that Gaia acts "intentionally" was a metaphoric statement in his popular initial book and was not meant to be taken literally. This new statement of the Gaia hypothesis was more acceptable to the scientific community. Most accusations of [[teleology|teleologism]] ceased, following this conference.<br />
洛夫洛克谨慎地提出了盖亚假说的一个版本,没有声称盖亚有意或有意识地维持着生命生存所需的复杂平衡。看来盖亚“故意”的行为是他最受欢迎的第一本书中的隐喻性陈述,并不是字面意思。盖亚假说的这一新说法更为科学界所接受。在这次会议之后,[[目的论|目的论]]的大多数指控都停止了。<br />
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===Third Gaia conference第三次盖亚会议===<br />
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By the time of the 2nd Chapman Conference on the Gaia Hypothesis, held at Valencia, Spain, on 23 June 2000,<ref>{{cite news|last=Simón|first=Federico|title=GEOLOGÍA Enfoque multidisciplinar La hipótesis Gaia madura en Valencia con los últimos avances científicos|journal=El País|date=21 June 2000|url=http://elpais.com/diario/2000/06/21/futuro/961538404_850215.html|accessdate=1 December 2013|language=spanish}}</ref> the situation had changed significantly. Rather than a discussion of the Gaian teleological views, or "types" of Gaia hypotheses, the focus was upon the specific mechanisms by which basic short term homeostasis was maintained within a framework of significant evolutionary long term structural change.<br />
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The major questions were:<ref>{{cite web|title=General Information Chapman Conference on the Gaia Hypothesis University of Valencia Valencia, Spain June 19-23, 2000 (Monday through Friday) |url=http://www.agu.org/meetings/chapman/chapman_archive/cc00bcall.html |work=AGU Meetings |accessdate=7 January 2017 |author=American Geophysical Union }}</ref><br />
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# "How has the global biogeochemical/climate system called Gaia changed in time? What is its history? Can Gaia maintain stability of the system at one time scale but still undergo vectorial change at longer time scales? How can the geologic record be used to examine these questions?"<br />
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# "What is the structure of Gaia? Are the feedbacks sufficiently strong to influence the evolution of climate? Are there parts of the system determined pragmatically by whatever disciplinary study is being undertaken at any given time or are there a set of parts that should be taken as most true for understanding Gaia as containing evolving organisms over time? What are the feedbacks among these different parts of the Gaian system, and what does the near closure of matter mean for the structure of Gaia as a global ecosystem and for the productivity of life?"<br />
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# "How do models of Gaian processes and phenomena relate to reality and how do they help address and understand Gaia? How do results from Daisyworld transfer to the real world? What are the main candidates for "daisies"? Does it matter for Gaia theory whether we find daisies or not? How should we be searching for daisies, and should we intensify the search? How can Gaian mechanisms be investigated using process models or global models of the climate system that include the biota and allow for chemical cycling?"<br />
“被称为盖亚的全球生物地球化学/气候系统是如何随时间变化的?它的历史是什么?盖亚能在一个时间尺度上保持系统的稳定性,但在较长的时间尺度上仍能经历向量变化吗?如何利用地质记录来检验这些问题?” <br />
“盖亚的结构是什么?反馈是否足够强烈,足以影响气候的演变?系统的某些部分是由任何给定时间正在进行的任何学科研究实际确定的,还是有一组应该被视为最真实的部分来理解盖亚,即随着时间的推移包含进化中的有机体?盖亚系统的这些不同部分之间的反馈是什么?物质的接近封闭对盖亚作为全球生态系统的结构和生命的生产力意味着什么?” <br />
“盖亚过程和现象的模型如何与现实联系起来,它们如何帮助解决和理解盖亚?雏菊世界的结果如何传递到真实世界?“雏菊”的主要候选对象是什么?我们是否找到雏菊对盖亚理论有意义吗?我们应该如何寻找雏菊,我们应该加强搜索?如何使用气候系统的过程模型或全球模型(包括生物群并允许化学循环)来研究盖安机制?” <br />
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In 1997, Tyler Volk argued that a Gaian system is almost inevitably produced as a result of an evolution towards far-from-equilibrium homeostatic states that maximise [[entropy]] production, and Kleidon (2004) agreed stating: "...homeostatic behavior can emerge from a state of MEP associated with the planetary albedo"; "...the resulting behavior of a biotic Earth at a state of MEP may well lead to near-homeostatic behavior of the Earth system on long time scales, as stated by the Gaia hypothesis". Staley (2002) has similarly proposed "...an alternative form of Gaia theory based on more traditional Darwinian principles... In [this] new approach, environmental regulation is a consequence of population dynamics, not Darwinian selection. The role of selection is to favor organisms that are best adapted to prevailing environmental conditions. However, the environment is not a static backdrop for evolution, but is heavily influenced by the presence of living organisms. The resulting co-evolving dynamical process eventually leads to the convergence of equilibrium and optimal conditions".<br />
1997年,泰勒·沃尔克认为,盖安系统几乎不可避免地会产生,这是朝着使熵产量最大化的远非平衡平衡平衡状态演化的结果,克莱顿(2004)同意这样的说法:“自稳行为可以从与行星反照率相关的MEP状态中产生”;“……生物地球在MEP状态下的行为很可能导致地球系统在长时间尺度上的近稳态行为,正如盖亚假说所述”。Staley(2002)同样提出了“……一种基于更传统的达尔文原理的盖亚理论的替代形式。在这种新方法中,环境调控是人口动态的结果,而不是达尔文的选择。选择的作用是偏爱最能适应当前环境条件的有机体。然而,环境并不是进化的静态背景,而是受到生物存在的严重影响。由此产生的共同进化动态过程最终导致平衡和最优条件的收敛。 <br />
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===Fourth Gaia conference第四次盖亚会议===<br />
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A fourth international conference on the Gaia hypothesis, sponsored by the Northern Virginia Regional Park Authority and others, was held in October 2006 at the Arlington, VA campus of George Mason University.<ref>{{cite web|title=Gaia Theory Conference at George Mason University Law School|url=http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|accessdate=1 December 2013|author=Official Site of Arlington County Virginia|archive-url=https://web.archive.org/web/20131203043657/http://www.arlingtonva.us/departments/Communications/PressReleases/page7530.aspx|archive-date=2013-12-03|url-status=dead}}</ref><br />
第四届盖亚假说国际会议于2006年10月在乔治梅森大学阿灵顿分校举行,会议由北弗吉尼亚州公园管理局和其他机构赞助。 <br />
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Martin Ogle, Chief Naturalist, for NVRPA, and long-time Gaia hypothesis proponent, organized the event. Lynn Margulis, Distinguished University Professor in the Department of Geosciences, University of Massachusetts-Amherst, and long-time advocate of the Gaia hypothesis, was a keynote speaker. Among many other speakers: Tyler Volk, Co-director of the Program in Earth and Environmental Science at New York University; Dr. Donald Aitken, Principal of Donald Aitken Associates; Dr. Thomas Lovejoy, President of the Heinz Center for Science, Economics and the Environment; Robert Correll, Senior Fellow, Atmospheric Policy Program, American Meteorological Society and noted environmental ethicist, J. Baird Callicott.<br />
马丁奥格尔,NVRPA的首席博物学家,也是盖亚假说的长期支持者,组织了这次活动。林恩 马古拉斯是马萨诸塞州阿默斯特大学地球科学系的杰出大学教授,也是盖亚假说的长期倡导者。其他许多发言者包括:纽约大学地球与环境科学项目联合主任泰勒·沃尔克、唐纳德·艾特肯博士、唐纳德·艾特肯博士、海因茨科学、经济与环境中心主席托马斯·洛夫乔伊博士、大气政策计划高级研究员罗伯特·科雷尔,美国气象学会和著名环境伦理学家J。贝尔德。卡利科特。 <br />
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This conference approached the Gaia hypothesis as both science and metaphor as a means of understanding how we might begin addressing 21st century issues such as climate change and ongoing environmental destruction.<br />
这次会议将盖亚假说作为一种科学和隐喻来探讨,以此来理解我们如何着手解决21世纪的问题,如气候变化和持续的环境破坏<br />
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==Criticism批评==<br />
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After initially receiving little attention from scientists (from 1969 until 1977), thereafter for a period the initial Gaia hypothesis was criticized by a number of scientists, such as [[Ford Doolittle]],<ref name=":1">{{Cite journal|last=Doolittle|first=W. F.|year=1981|title=Is Nature Really Motherly|url=|journal=The Coevolution Quarterly|volume=Spring|pages=58–63|via=}}</ref> [[Richard Dawkins]]<ref name=":2">{{Cite book|title=The Extended Phenotype: the Long Reach of the Gene|last=Dawkins|first=Richard|publisher=Oxford University Press|year=1982|isbn=978-0-19-286088-0|location=|pages=}}</ref> and [[Stephen Jay Gould]].<ref name="ReferenceB">Turney, Jon. "Lovelock and Gaia: Signs of Life" (Revolutions in Science)</ref> Lovelock has said that because his hypothesis is named after a Greek goddess, and championed by many non-scientists,<ref name="Lovelock01"/> the Gaia hypothesis was interpreted as a [[neo-Pagan]] [[religion]]. Many scientists in particular also criticised the approach taken in his popular book ''Gaia, a New Look at Life on Earth'' for being [[teleology|teleological]]—a belief that things are purposeful and aimed towards a goal. Responding to this critique in 1990, Lovelock stated, "Nowhere in our writings do we express the idea that planetary self-regulation is purposeful, or involves foresight or planning by the [[biota (ecology)|biota]]".<br />
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最初很少受到科学家的关注(从1969年到1977年),此后的一段时间里,最初的盖亚假说受到了许多科学家的批评,比如福特·杜利特,理查德·道金斯和斯蒂芬·杰伊·古尔德洛夫洛克曾说过,因为他的假设是以希腊女神的名字命名的,新盖亚假说被许多非教派的科学家解释为。特别是许多科学家还批评了他的畅销书《盖亚》中采用的方法,认为地球上的生命是目的论的,认为事物是有目的的,是有目的的。洛夫洛克在1990年回应这一批评时说:“在我们的著作中我们没有任何地方表达行星自我调节是有目的的,或涉及生物群的远见或计划。”<br />
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[[Stephen Jay Gould]] criticised Gaia as being "a metaphor, not a mechanism."<ref name="Gould 1997">{{cite journal |author=Gould S.J. |title=Kropotkin was no crackpot |journal=Natural History |volume=106 |pages=12–21 |date=June 1997 |url=http://libcom.org/library/kropotkin-was-no-crackpot |ref=harv}}</ref> He wanted to know the actual mechanisms by which self-regulating homeostasis was achieved. In his defense of Gaia, David Abram argues that Gould overlooked the fact that "mechanism", itself, is a metaphor — albeit an exceedingly common and often unrecognized metaphor — one which leads us to consider natural and living systems as though they were machines organized and built from outside (rather than as [[autopoiesis|autopoietic]] or self-organizing phenomena). Mechanical metaphors, according to Abram, lead us to overlook the active or agential quality of living entities, while the organismic metaphorics of the Gaia hypothesis accentuate the active agency of both the biota and the biosphere as a whole.<ref>Abram, D. (1988) "The Mechanical and the Organic: On the Impact of Metaphor in Science" in Scientists on Gaia, edited by Stephen Schneider and Penelope Boston, Cambridge, Massachusetts: MIT Press, 1991</ref><ref>{{cite web|url=http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |title=The Mechanical and the Organic |accessdate=August 27, 2012 |url-status=dead |archiveurl=https://web.archive.org/web/20120223165936/http://www.wildethics.org/essays/the_mechanical_and_the_organic.html |archivedate=February 23, 2012 }}</ref> With regard to causality in Gaia, Lovelock argues that no single mechanism is responsible, that the connections between the various known mechanisms may never be known, that this is accepted in other fields of biology and ecology as a matter of course, and that specific hostility is reserved for his own hypothesis for other reasons.<ref name="Lovelock, James 2001">Lovelock, James (2001), ''Homage to Gaia: The Life of an Independent Scientist'' (Oxford University Press)</ref><br />
史蒂芬·杰伊·古尔德批评盖亚是“一种隐喻,而不是一种机制。”他想知道实现自我调节内稳态的实际机制。在为盖亚辩护时,大卫·艾布拉姆认为古尔德忽略了一个事实,即“机制”本身就是一个隐喻——尽管这是一个非常常见且常常未被人认识的隐喻——它使我们把自然和生命系统看作是从外部组织和建造的机器(而不是自动或自组织的)现象)。艾布拉姆认为,机械隐喻使我们忽视了生命实体的活动性或能动性,而盖亚假说的有机体隐喻强调了生物群和生物圈作为一个整体的能动性。关于盖亚的因果关系,洛夫洛克认为没有单一的机制负责各种已知机制之间的联系可能永远不为人所知,这一点在其他生物学和生态学领域都是理所当然的,而具体的敌意是出于其他原因留给他自己的假设的<br />
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Aside from clarifying his language and understanding of what is meant by a life form, Lovelock himself ascribes most of the criticism to a lack of understanding of non-linear mathematics by his critics, and a linearizing form of [[greedy reductionism]] in which all events have to be immediately ascribed to specific causes before the fact. He also states that most of his critics are biologists but that his hypothesis includes experiments in fields outside biology, and that some self-regulating phenomena may not be mathematically explainable.<ref name="Lovelock, James 2001"/><br />
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除了澄清自己的语言和对生命形式的理解之外,洛夫洛克自己将大部分批评归咎于批评家对非线性数学的缺乏理解,以及贪婪还原论的线性化形式,在这种形式中,所有事件都必须在事实发生之前立即归因于特定的原因。他还指出,批评他的人大多是生物学家,但他的假设包括生物学以外领域的实验,有些自我调节的现象可能无法用数学解释 <br />
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===Natural selection and evolution自然选择和进化===<br />
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Lovelock has suggested that global biological feedback mechanisms could evolve by [[natural selection]], stating that organisms that improve their environment for their survival do better than those that damage their environment. However, in the early 1980s, [[Ford Doolittle|W. Ford Doolittle]] and [[Richard Dawkins]] separately argued against this aspect of Gaia. Doolittle argued that nothing in the [[genome]] of individual organisms could provide the feedback mechanisms proposed by Lovelock, and therefore the Gaia hypothesis proposed no plausible mechanism and was unscientific.<ref name=":1" /> Dawkins meanwhile stated that for organisms to act in concert would require foresight and planning, which is contrary to the current scientific understanding of evolution.<ref name=":2" /> Like Doolittle, he also rejected the possibility that feedback loops could stabilize the system.<br />
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洛夫洛克提出,全球生物反馈机制可以通过自然选择而进化,他指出,为生存而改善环境的生物比那些破坏环境的生物做得更好。然而,在20世纪80年代早期,W·福特·杜立德和理查德·道金斯分别反对盖亚的这一方面。杜立德认为,单个生物体的基因组中没有任何东西能够提供洛夫洛克提出的反馈机制,因此盖亚假说没有提出任何合理的机制,是不科学的。道金斯同时指出,要使有机体协同行动,就需要有远见和计划,这与当前科学界对进化论的理解相悖和杜立德一样,他也拒绝了反馈回路可以稳定系统的可能性。<br />
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[[Lynn Margulis]], a microbiologist who collaborated with Lovelock in supporting the Gaia hypothesis, argued in 1999, that "[[Charles Darwin|Darwin]]'s grand vision was not wrong, only incomplete. In accentuating the direct competition between individuals for resources as the primary selection mechanism, Darwin (and especially his followers) created the impression that the environment was simply a static arena". She wrote that the composition of the Earth's atmosphere, hydrosphere, and lithosphere are regulated around "set points" as in [[homeostasis]], but those set points change with time.<ref name="ReferenceA">Margulis, Lynn. Symbiotic Planet: A New Look At Evolution. Houston: Basic Book 1999</ref><br />
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Lynn Margulis,一位与Lovelock合作支持盖亚假说的微生物学家,在1999年指出,“达尔文的宏伟愿景没有错,只是不完整。达尔文(特别是他的追随者)强调个人之间对资源的直接竞争是主要的选择机制,他给人的印象是环境只是一个静态的竞技场”。她写道,地球大气、水圈和岩石圈的组成都是围绕着“设定点”来调节的,就像在体内平衡中一样,但是这些设定点会随着时间的推移而变化 <br />
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Evolutionary biologist [[W. D. Hamilton]] called the concept of Gaia [[Nicolaus Copernicus|Copernican]], adding that it would take another [[Isaac Newton|Newton]] to explain how Gaian self-regulation takes place through Darwinian [[natural selection]].<ref name=vanish09>Lovelock, James. ''The Vanishing Face of Gaia''. Basic Books, 2009, pp. 195-197. {{ISBN|978-0-465-01549-8}}</ref>{{better source|date=September 2012|reason=it should be possible to find the original place where Hamilton said this}} More recently [[Ford Doolittle]] building on his and Inkpen's ITSNTS (It's The Singer Not The Song) proposal<ref name="ITSNTS">Doolittle WF, Inkpen SA. Processes and patterns of interaction as units of selection: An introduction to ITSNTS thinking. [https://www.pnas.org/content/115/16/4006 PNAS April 17, 2018 115 (16)] 4006-4014 </ref> proposed that differential persistence can play a similar role to differential reproduction in evolution by natural selections, thereby providing a possible reconciliation between the theory of natural selection and the Gaia hypothesis<ref name="Darwinizing Gaia">Doolittle WF. Darwinizing Gaia. [https://doi.org/10.1016/j.jtbi.2017.02.015 Journal of Theoretical BiologyVolume 434], 7 December 2017, Pages 11-19 </ref>. <br />
进化生物学家汉密尔顿称盖亚哥白尼为盖亚的概念,他补充说,需要另一个牛顿来解释盖安的自我调节是如何通过达尔文的自然选择发生的。通过自然选择在进化过程中的繁殖,从而为自然选择理论和盖亚假说提供了可能的调和。 <br />
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===Criticism in the 21st century21世纪的批评===<br />
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The Gaia hypothesis continues to be broadly skeptically received by the scientific community. For instance, arguments both for and against it were laid out in the journal ''Climatic Change'' in 2002 and 2003. A significant argument raised against it are the many examples where life has had a detrimental or destabilising effect on the environment rather than acting to regulate it.<ref name="kirchner2002"/><ref name="volk2002"/> Several recent books have criticised the Gaia hypothesis, expressing views ranging from "... the Gaia hypothesis lacks unambiguous observational support and has significant theoretical difficulties"<ref>{{cite book |last=Waltham |first=David |authorlink=David Waltham |date=2014 |title=Lucky Planet: Why Earth is Exceptional – and What that Means for Life in the Universe |url=https://archive.org/details/luckyplanetwhyea0000walt |location= |publisher=Icon Books |page= |isbn=9781848316560 |accessdate= |url-access=registration }}</ref> to "Suspended uncomfortably between tainted metaphor, fact, and false science, I prefer to leave Gaia firmly in the background"<ref name="beerling2007"/> to "The Gaia hypothesis is supported neither by evolutionary theory nor by the empirical evidence of the geological record".<ref>{{cite book |last1=Cockell |first1=Charles |authorlink1=Charles Cockell |last2=Corfield |first2=Richard |last3=Dise |first3= Nancy |last4=Edwards |first4=Neil |last5=Harris |first5=Nigel |date=2008 |title= An Introduction to the Earth-Life System |url= http://www.cambridge.org/us/academic/subjects/earth-and-environmental-science/palaeontology-and-life-history/introduction-earth-life-system |location=Cambridge (UK) |publisher= Cambridge University Press |page= |isbn= 9780521729536 |accessdate= }}</ref> The [[CLAW hypothesis]],<ref name="CLAW87" /> initially suggested as a potential example of direct Gaian feedback, has subsequently been found to be less credible as understanding of [[cloud condensation nuclei]] has improved.<ref>{{Citation |last1= Quinn |first1=P.K. |last2= Bates |first2=T.S. |title =The case against climate regulation via oceanic phytoplankton sulphur emissions |journal =Nature |volume=480 |issue=7375 |pages =51–56 |date = 2011 |doi=10.1038/nature10580|bibcode = 2011Natur.480...51Q |pmid=22129724|url=https://zenodo.org/record/1233319 }}</ref> In 2009 the [[Medea hypothesis]] was proposed: that life has highly detrimental (biocidal) impacts on planetary conditions, in direct opposition to the Gaia hypothesis.<ref>Peter Ward (2009), ''The Medea Hypothesis: Is Life on Earth Ultimately Self-Destructive?'', {{ISBN|0-691-13075-2}}</ref><br />
盖亚假说仍然受到科学界的广泛怀疑。例如,在2003年和2002年的《气候变化》杂志上都提出了反对意见。反对它的一个重要论点是许多例子,其中生命对环境产生了有害或不稳定的影响,而不是采取行动来调节它。最近几本书批评了盖亚假说,表达了从“盖亚假说缺乏明确的观察支持,并且有重大的理论困难“到”令人不安地徘徊在污点隐喻、事实和虚假科学之间,我宁愿把盖亚牢牢地放在背景中“到”盖亚假说既没有进化论的支持,也没有地质记录的经验证据的支持。爪假说最初被认为是盖安直接反馈的一个潜在例子,后来被发现对云的理解不那么可信凝聚核已经得到了改善2009年,美狄亚假说被提出:生命对行星的状况有非常有害的(杀生的)影响,这与盖亚假说直接相反 <br />
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In a 2013 book-length evaluation of the Gaia hypothesis considering modern evidence from across the various relevant disciplines, Toby Tyrrell concluded that: "I believe Gaia is a dead end. Its study has, however, generated many new and thought provoking questions. While rejecting Gaia, we can at the same time appreciate Lovelock's originality and breadth of vision, and recognise that his audacious concept has helped to stimulate many new ideas about the Earth, and to champion a holistic approach to studying it".<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=209 |isbn=9780691121581 |accessdate= }}</ref> Elsewhere he presents his conclusion "The Gaia hypothesis is not an accurate picture of how our world works".<ref>{{Citation |last= Tyrrell |first = Toby |title =Gaia: the verdict is… |journal = New Scientist |volume = 220 |issue = 2940 |pages = 30–31 |date= 26 October 2013 |doi=10.1016/s0262-4079(13)62532-4}}</ref> This statement needs to be understood as referring to the "strong" and "moderate" forms of Gaia—that the biota obeys a principle that works to make Earth optimal (strength 5) or favourable for life (strength 4) or that it works as a homeostatic mechanism (strength 3). The latter is the "weakest" form of Gaia that Lovelock has advocated. Tyrrell rejects it. However, he finds that the two weaker forms of Gaia—Coeveolutionary Gaia and Influential Gaia, which assert that there are close links between the evolution of life and the environment and that biology affects the physical and chemical environment—are both credible, but that it is not useful to use the term "Gaia" in this sense and that those two forms were already accepted and explained by the processes of natural selection and adaptation.<ref>{{citation |last=Tyrrell |first=Toby |authorlink= |date= 2013|title= On Gaia: A Critical Investigation of the Relationship between Life and Earth |url=http://press.princeton.edu/titles/9959.html |location=Princeton |publisher=Princeton University Press |page=208 |isbn=9780691121581 |accessdate= }}</ref><br />
2013年,托比·泰瑞尔在对盖亚假说的一本书长度评估中总结道:“我认为盖亚是一条死胡同。然而,它的研究产生了许多新的和发人深省的问题。在拒绝盖亚的同时,我们也能欣赏到洛夫洛克的独创性和广博的视野,并认识到他大胆的概念有助于激发许多关于地球的新思想,并倡导一种研究地球的整体方法。”在其他地方,他提出了自己的结论:“盖亚假说并不是一个关于如何进行的精确描述我们的世界在运转。”这种说法需要被理解为是指盖亚的“强大”和“温和”形式,生物群遵循的原则是使地球处于最佳状态(强度5)或有利于生命(强度4),或者它作为一种内稳态机制(强度3)。后者是洛夫洛克所提倡的盖亚的“最弱”形式。泰瑞尔拒绝了。然而,他发现盖亚的两种较弱的形式共同进化盖亚和有影响力的盖亚,它们断言生命的进化和环境之间有密切的联系,生物学影响物理和化学环境,这两种说法都是可信的,但在这个意义上使用“盖亚”一词是没有用的两种形式已经被自然选择和适应过程所接受和解释 <br />
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Category:Superorganisms<br />
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{{Portal|Environment|Earth sciences|Geography}}<br />
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Category:Climate change feedbacks<br />
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<small>This page was moved from [[wikipedia:en:Gaia hypothesis]]. Its edit history can be viewed at [[盖亚假说/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henryhttps://wiki.swarma.org/index.php?title=%E8%80%97%E6%95%A3&diff=18460耗散2020-11-16T08:58:52Z<p>Henry:</p>
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<div>此词条暂由Henry翻译<br />
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In [[thermodynamics]], '''dissipation''' is the result of an [[irreversible process]] that takes place in homogeneous [[Thermodynamic system|thermodynamic systems]]. A dissipative process is a process in which [[energy]] ([[Internal energy|internal]], bulk flow [[Kinetic energy|kinetic]], or system [[Potential energy|potential]]) is [[Energy transformation|transformed]] from some initial form to some final form; the capacity of the final form to do [[mechanical work]] is less than that of the initial form. For example, [[Heat Transfer|heat transfer]] is dissipative because it is a transfer of internal energy from a hotter body to a colder one. Following the [[second law of thermodynamics]], the [[entropy]] varies with [[temperature]] (reduces the capacity of the combination of the two bodies to do mechanical work), but never decreases in an isolated system.<br />
在[[热力学]]中,“耗散”是在均质[[热力学系统|热力学系统]]中发生的[[不可逆过程]]的结果。耗散过程是一个过程,其中[[能量]]([[内能|内部]]、体积流[[动能|动能]]或系统[[势能|势能])从某种初始形式到某种最终形式的[[能量转换|转换]];最终形式做[[机械功]]的能力小于初始形式。例如,[[热传递]]具有耗散性,因为它是一种将内部能量从较热的物体转移到较冷的物体的过程。遵循[[热力学第二定律],[[熵]]随[[温度]]而变化(降低了两个物体结合起来做机械功的能力),但在孤立系统中不会降低。<br />
In thermodynamics, dissipation is the result of an irreversible process that takes place in homogeneous thermodynamic systems. A dissipative process is a process in which energy (internal, bulk flow kinetic, or system potential) is transformed from some initial form to some final form; the capacity of the final form to do mechanical work is less than that of the initial form. For example, heat transfer is dissipative because it is a transfer of internal energy from a hotter body to a colder one. Following the second law of thermodynamics, the entropy varies with temperature (reduces the capacity of the combination of the two bodies to do mechanical work), but never decreases in an isolated system.<br />
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在热力学中,<font color="#ff8000"> 耗散Dissipation</font>是在均匀热力学系统中发生的不可逆性的结果。耗散过程是能量(内部、整体流动动力学或系统势)从某种初始形式转化为某种最终形式的过程,最终形式做机械功的能力小于初始形式。例如,热传递是耗散的,因为它是内部能量从一个较热的物体向一个较冷的物体的转移。在热力学第二定律之后,熵随温度变化(降低了两个物体组合做机械功的能力) ,但是在一个孤立的系统中熵不会减少。<br />
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These processes produce entropy (see [[entropy production]]) at a certain rate. The entropy production rate times ambient temperature gives the dissipated [[Power (physics)|power]]. Important examples of irreversible processes are: [[heat flow]] through a [[thermal resistance]], [[fluid flow]] through a flow resistance, diffusion (mixing), [[Chemical reaction|chemical reactions]], and [[Electric current|electrical current]] flow through an [[Electrical resistance and conductance|electrical resistance]] ([[Joule heating]]).<br />
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These processes produce entropy (see entropy production) at a certain rate. The entropy production rate times ambient temperature gives the dissipated power. Important examples of irreversible processes are: heat flow through a thermal resistance, fluid flow through a flow resistance, diffusion (mixing), chemical reactions, and electrical current flow through an electrical resistance (Joule heating).<br />
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这些过程以一定的速率产生熵(见产生熵)。产生熵速率乘以环境温度就得到了耗散功率。不可逆过程的重要例子有: 热流过热阻,流体流过流阻,扩散(混合) ,化学反应,电流流过电阻(焦耳加热)。<br />
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== Definition 定义==<br />
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Thermodynamic dissipative processes are essentially irreversible. They [[entropy production|produce entropy]] at a finite rate. In a process in which the temperature is locally continuously defined, the local density of rate of entropy production times local temperature gives the local density of dissipated power.[Definition needed!]<br />
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Thermodynamic dissipative processes are essentially irreversible. They produce entropy at a finite rate. In a process in which the temperature is locally continuously defined, the local density of rate of entropy production times local temperature gives the local density of dissipated power.[Definition needed!]<br />
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热力学耗散过程本质上是不可逆的。它们以有限的速率产生熵。在一个局部连续定义温度的过程中,产生熵的局部密度乘以局部温度得到局部耗散功率密度。[需要定义! ]<br />
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A particular occurrence of a dissipative process cannot be described by a single individual [[Hamiltonian mechanics|Hamiltonian]] formalism. A dissipative process requires a collection of admissible individual Hamiltonian descriptions, exactly which one describes the actual particular occurrence of the process of interest being unknown. This includes friction, and all similar forces that result in decoherency of energy&mdash;that is, conversion of [[Coherence (physics)|coherent]] or directed energy flow into an indirected or more [[isotropic]] distribution of energy.<br />
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A particular occurrence of a dissipative process cannot be described by a single individual Hamiltonian formalism. A dissipative process requires a collection of admissible individual Hamiltonian descriptions, exactly which one describes the actual particular occurrence of the process of interest being unknown. This includes friction, and all similar forces that result in decoherency of energy&mdash;that is, conversion of coherent or directed energy flow into an indirected or more isotropic distribution of energy.<br />
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耗散过程的一个特殊现象不能用一个单独的哈密顿形式来描述。耗散过程需要一组可容许的个体哈密顿描述集合,确切地说,哪一个描述了未知过程的实际特定发生。这包括摩擦力和所有导致能量消相干的类似力,即将相干或定向能量流转换为间接或更各向同性的能量分布<br />
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=== Energy 能量===<br />
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"The conversion of mechanical energy into heat is called energy dissipation." – ''François Roddier''<ref>[http://www.editions-parole.net/?product=thermodynamique-de-levolution-un-essai-de-thermo-bio-sociologie Roddier F., ''Thermodynamique de l'évolution (The Thermodynamics of Evolution)'', parole éditions, 2012]</ref> The term is also applied to the loss of energy due to generation of unwanted heat in electric and electronic circuits.<br />
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"The conversion of mechanical energy into heat is called energy dissipation." – François Roddier The term is also applied to the loss of energy due to generation of unwanted heat in electric and electronic circuits.<br />
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机械能转化为热量的过程叫做能量耗散,这一术语也用于指电子电路中由于产生不需要的热量而造成的能量损失<br />
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=== Computational physics计算物理学 ===<br />
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In [[computational physics]], numerical dissipation (also known as "numerical diffusion") refers to certain side-effects that may occur as a result of a numerical solution to a differential equation. When the pure [[advection]] equation, which is free of dissipation, is solved by a numerical approximation method, the energy of the initial wave may be reduced in a way analogous to a diffusional process. Such a method is said to contain 'dissipation'. In some cases, "artificial dissipation" is intentionally added to improve the [[numerical stability]] characteristics of the solution.<ref>Thomas, J.W. Numerical Partial Differential Equation: Finite Difference Methods. Springer-Verlag. New York. (1995)</ref><br />
在[[计算物理]]中,数值耗散(也称为“数值扩散”)是指微分方程数值解可能产生的某些副作用。当用数值近似方法求解无耗散的纯[[平流]]方程时,初始波的能量可以用类似于扩散过程的方式降低。这种方法被称为包含“耗散”。在某些情况下,故意添加“人工耗散”来改善解的[[数值稳定性]]特性。 <br />
In computational physics, numerical dissipation (also known as "numerical diffusion") refers to certain side-effects that may occur as a result of a numerical solution to a differential equation. When the pure advection equation, which is free of dissipation, is solved by a numerical approximation method, the energy of the initial wave may be reduced in a way analogous to a diffusional process. Such a method is said to contain 'dissipation'. In some cases, "artificial dissipation" is intentionally added to improve the numerical stability characteristics of the solution.<br />
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在计算物理学中,数值耗散(也称为“数值扩散”)是指数值求解微分方程可能产生的某些副作用。当用数值近似方法求解无耗散的纯对流方程时,可以用类似于扩散过程的方式来降低初始波的能量。这种方法被称为包含“耗散”。在某些情况下,可以通过特意添加“人工耗散”来改善解的数值稳定性。 <br />
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=== Mathematics数学 ===<br />
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A formal, mathematical definition of dissipation, as commonly used in the mathematical study of [[measure-preserving dynamical system]]s, is given in the article ''[[wandering set]]''.<br />
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A formal, mathematical definition of dissipation, as commonly used in the mathematical study of measure-preserving dynamical systems, is given in the article wandering set.<br />
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本文给出了在保测度动力系统的数学研究中常用的耗散的形式化数学定义。<br />
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== Examples例子 ==<br />
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=== In hydraulic engineering 水利工程 ===<br />
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Dissipation is the process of converting mechanical energy of downward-flowing water into thermal and acoustical energy. Various devices are designed in stream beds to reduce the kinetic energy of flowing waters to reduce their [[erosion|erosive potential]] on banks and [[stream bed|river bottoms]]. Very often, these devices look like small [[waterfall]]s or [[waterfall#Types|cascades]], where water flows vertically or over [[riprap]] to lose some of its [[kinetic energy]].<br />
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Dissipation is the process of converting mechanical energy of downward-flowing water into thermal and acoustical energy. Various devices are designed in stream beds to reduce the kinetic energy of flowing waters to reduce their erosive potential on banks and river bottoms. Very often, these devices look like small waterfalls or cascades, where water flows vertically or over riprap to lose some of its kinetic energy.<br />
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耗散是将向下流动的水的机械能转化为热能和声能的过程。在河床上设计了各种装置,以降低流动水的动能,减少它们对河岸和河底的侵蚀潜力。很多时候,这些装置看起来像小瀑布或瀑布,水流垂直流动或越过抛石,同时失去一些动能。<br />
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=== Irreversible processes不可逆转过程 ===<br />
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Important examples of irreversible processes are: <br />
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Important examples of irreversible processes are: <br />
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不可逆过程的重要例子有:<br />
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# Heat flow through a thermal resistance<br />
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Heat flow through a thermal resistance<br />
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热流过热阻<br />
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# Fluid flow through a flow resistance<br />
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Fluid flow through a flow resistance<br />
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流体流过流动阻力<br />
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# Diffusion (mixing)<br />
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Diffusion (mixing)<br />
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扩散(混合)<br />
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# Chemical reactions<ref>Glansdorff, P., [[Ilya Prigogine|Prigogine, I.]] (1971). ''Thermodynamic Theory of Structure, Stability, and Fluctuations'', Wiley-Interscience, London, 1971, {{ISBN|0-471-30280-5}}, p. 61.</ref><ref>Eu, B.C. (1998). ''Nonequilibrium Thermodynamics: Ensemble Method'', Kluwer Academic Publications, Dordrecht, {{ISBN|0-7923-4980-6}}, p. 49,</ref><br />
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Chemical reactions<br />
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化学反应<br />
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# Electrical current flow through an electrical resistance ([[Joule heating]]).<br />
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Electrical current flow through an electrical resistance (Joule heating).<br />
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电流通过电阻(焦耳加热)。<br />
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=== Waves or oscillations波或振荡 ===<br />
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[[Wave]]s or [[oscillation]]s, lose [[energy]] over [[time]], typically from [[friction]] or [[turbulence]]. In many cases, the "lost" energy raises the [[temperature]] of the system. For example, a [[wave]] that loses [[amplitude]] is said to dissipate. The precise nature of the effects depends on the nature of the wave: an [[atmospheric wave]], for instance, may dissipate close to the surface due to [[friction]] with the land mass, and at higher levels due to [[radiative cooling]].<br />
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Waves or oscillations, lose energy over time, typically from friction or turbulence. In many cases, the "lost" energy raises the temperature of the system. For example, a wave that loses amplitude is said to dissipate. The precise nature of the effects depends on the nature of the wave: an atmospheric wave, for instance, may dissipate close to the surface due to friction with the land mass, and at higher levels due to radiative cooling.<br />
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波或振荡,随着时间的推移会失去能量,通常是由于摩擦或紊流。在许多情况下,“损失”的能量提高了系统的温度。例如,失去振幅的波叫做消散波。影响的确切性质取决于波的性质: 例如,大气波可能由于与陆地质量的摩擦而于接近地表处消散,由于辐射冷却的缘故而在更高的水平上消散。<br />
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== History历史 ==<br />
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{{See also |Timeline of thermodynamics}}<br />
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The concept of dissipation was introduced in the field of thermodynamics by [[William Thomson, 1st Baron Kelvin|William Thomson]] (Lord Kelvin) in 1852.<ref>W. Thomson ''On the universal tendency in nature to the dissipation of mechanical energy'' Philosophical Magazine, Ser. 4, p.&nbsp;304 (1852).</ref> Lord Kelvin deduced that a subset of the above-mentioned irreversible dissipative processes will occur unless a process is governed by a "perfect thermodynamic engine". The processes that Lord Kelvin identified were friction, diffusion, conduction of heat and the absorption of light.<br />
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The concept of dissipation was introduced in the field of thermodynamics by William Thomson (Lord Kelvin) in 1852. Lord Kelvin deduced that a subset of the above-mentioned irreversible dissipative processes will occur unless a process is governed by a "perfect thermodynamic engine". The processes that Lord Kelvin identified were friction, diffusion, conduction of heat and the absorption of light.<br />
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耗散的概念是由威廉·汤姆森(开尔文勋爵)于1852年在热力学领域提出的。开尔文勋爵推断,上述不可逆耗散过程的一个子集将会发生,除非一个过程由一个“完美的热力学发动机”控制。开尔文勋爵确定的过程是摩擦、扩散、热传导和光吸收。<br />
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==See also参见==<br />
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*[[Entropy production]]<br />
熵产生<br />
*[[Flood control]]<br />
防洪<br />
*[[Principle of maximum entropy]]<br />
最大熵准则<br />
*[[Two-dimensional gas]]<br />
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二维气体<br />
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==References参考==<br />
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{{Reflist}}<br />
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{{Footer energy}}<br />
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[[Category:Thermodynamic processes]]<br />
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Category:Thermodynamic processes<br />
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类别: 热力学过程<br />
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[[Category:Non-equilibrium thermodynamics]]<br />
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Category:Non-equilibrium thermodynamics<br />
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类别: 非平衡态热力学<br />
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[[Category:Dynamical systems]]<br />
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Category:Dynamical systems<br />
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类别: 动力系统<br />
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<noinclude><br />
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<small>This page was moved from [[wikipedia:en:Dissipation]]. Its edit history can be viewed at [[耗散/edithistory]]</small></noinclude><br />
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[[Category:待整理页面]]</div>Henry