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| | 一个实际的测量只反映了一个解,代表了其潜在理论的对称性的破缺。在这里“隐藏”是比“破坏”更好的术语,因为对称性总是存在于这些方程中。这种现象被称为自发对称破缺(SSB),因为(我们所知道的)没有任何东西会打破方程中的对称性。 | | 一个实际的测量只反映了一个解,代表了其潜在理论的对称性的破缺。在这里“隐藏”是比“破坏”更好的术语,因为对称性总是存在于这些方程中。这种现象被称为自发对称破缺(SSB),因为(我们所知道的)没有任何东西会打破方程中的对称性。 |
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| − | ====Chiral symmetry==== | + | ====Chiral symmetry 手性对称性==== |
| | {{Main article|Chiral symmetry breaking}} | | {{Main article|Chiral symmetry breaking}} |
| | Chiral symmetry breaking is an example of spontaneous symmetry breaking affecting the [[chiral symmetry]] of the [[strong interactions]] in particle physics. It is a property of [[quantum chromodynamics]], the [[quantum field theory]] describing these interactions, and is responsible for the bulk of the mass (over 99%) of the [[nucleons]], and thus of all common matter, as it converts very light bound [[quarks]] into 100 times heavier constituents of [[baryons]]. The approximate [[Nambu–Goldstone boson]]s in this spontaneous symmetry breaking process are the [[pions]], whose mass is an order of magnitude lighter than the mass of the nucleons. It served as the prototype and significant ingredient of the Higgs mechanism underlying the electroweak symmetry breaking. | | Chiral symmetry breaking is an example of spontaneous symmetry breaking affecting the [[chiral symmetry]] of the [[strong interactions]] in particle physics. It is a property of [[quantum chromodynamics]], the [[quantum field theory]] describing these interactions, and is responsible for the bulk of the mass (over 99%) of the [[nucleons]], and thus of all common matter, as it converts very light bound [[quarks]] into 100 times heavier constituents of [[baryons]]. The approximate [[Nambu–Goldstone boson]]s in this spontaneous symmetry breaking process are the [[pions]], whose mass is an order of magnitude lighter than the mass of the nucleons. It served as the prototype and significant ingredient of the Higgs mechanism underlying the electroweak symmetry breaking. |
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| − | ====Higgs mechanism==== | + | 手性对称破缺是粒子物理中影响强相互作用手性对称的自发对称破缺的一个例子。手性对称性破缺是量子色动力学(描述这些相互作用的量子场理论)的一种特性,它是核子的大部分质量(超过99%)的成因,因此也是所有普通物质的主要成因,因为它将非常轻的束缚夸克转化为100倍重量的重子的成分。在这个自发对称破缺过程中,近似的南部-戈德斯通玻色子是介子,其质量比核子的质量轻一个数量级。它是电弱对称破缺的希格斯机制的原型和重要组成部分。 |
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| | + | ====Higgs mechanism 希格斯机制==== |
| | {{Main article|Higgs mechanism|Yukawa interaction}} | | {{Main article|Higgs mechanism|Yukawa interaction}} |
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| | The strong, weak, and electromagnetic forces can all be understood as arising from [[gauge symmetry|gauge symmetries]]. The [[Higgs mechanism]], the spontaneous symmetry breaking of gauge symmetries, is an important component in understanding the [[superconductivity]] of metals and the origin of particle masses in the standard model of particle physics. One important consequence of the distinction between true symmetries and ''gauge symmetries'', is that the spontaneous breaking of a gauge symmetry does not give rise to characteristic massless Nambu–Goldstone physical modes, but only massive modes, like the plasma mode in a superconductor, or the Higgs mode observed in particle physics. | | The strong, weak, and electromagnetic forces can all be understood as arising from [[gauge symmetry|gauge symmetries]]. The [[Higgs mechanism]], the spontaneous symmetry breaking of gauge symmetries, is an important component in understanding the [[superconductivity]] of metals and the origin of particle masses in the standard model of particle physics. One important consequence of the distinction between true symmetries and ''gauge symmetries'', is that the spontaneous breaking of a gauge symmetry does not give rise to characteristic massless Nambu–Goldstone physical modes, but only massive modes, like the plasma mode in a superconductor, or the Higgs mode observed in particle physics. |
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| | + | 强、弱和电磁力都可以理解为来自规范对称。希格斯机制,即规范对称的自发对称破缺机制,是理解金属超导性和粒子物理标准模型中粒子质量起源的重要组成部分。区分真正的对称性和规范对称性的一个重要的结果,是规范对称性的自发破缺不产生典型的无质量Nambu-Goldstone物理模式,而是只产生有质量的模式,像超导体中的等离子体模式,或者粒子物理学中观察到的希格斯模式。 |
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| | In the standard model of particle physics, spontaneous symmetry breaking of the {{nowrap|SU(2) × U(1)}} gauge symmetry associated with the electro-weak force generates masses for several particles, and separates the electromagnetic and weak forces. The [[W and Z bosons]] are the elementary particles that mediate the [[weak interaction]], while the [[photon]] mediates the [[electromagnetic interaction]]. At energies much greater than 100 GeV, all these particles behave in a similar manner. The [[Unified field theory#Modern progress|Weinberg–Salam theory]] predicts that, at lower energies, this symmetry is broken so that the photon and the massive W and Z bosons emerge.<ref>A Brief History of Time, Stephen Hawking, Bantam; 10th anniversary edition (1998). pp. 73–74.{{ISBN?}}</ref> In addition, fermions develop mass consistently. | | In the standard model of particle physics, spontaneous symmetry breaking of the {{nowrap|SU(2) × U(1)}} gauge symmetry associated with the electro-weak force generates masses for several particles, and separates the electromagnetic and weak forces. The [[W and Z bosons]] are the elementary particles that mediate the [[weak interaction]], while the [[photon]] mediates the [[electromagnetic interaction]]. At energies much greater than 100 GeV, all these particles behave in a similar manner. The [[Unified field theory#Modern progress|Weinberg–Salam theory]] predicts that, at lower energies, this symmetry is broken so that the photon and the massive W and Z bosons emerge.<ref>A Brief History of Time, Stephen Hawking, Bantam; 10th anniversary edition (1998). pp. 73–74.{{ISBN?}}</ref> In addition, fermions develop mass consistently. |