更改

The study of differential equations is a wide field in pure and applied mathematics, physics, and engineering. All of these disciplines are concerned with the properties of differential equations of various types. Pure mathematics focuses on the existence and uniqueness of solutions, while applied mathematics emphasizes the rigorous justification of the methods for approximating solutions. Differential equations play an important role in modeling virtually every physical, technical, or biological process, from celestial motion, to bridge design, to interactions between neurons. Differential equations such as those used to solve real-life problems may not necessarily be directly solvable, i.e. do not have closed form solutions. Instead, solutions can be approximated using numerical methods.

The study of differential equations is a wide field in pure and applied mathematics, physics, and engineering. All of these disciplines are concerned with the properties of differential equations of various types. Pure mathematics focuses on the existence and uniqueness of solutions, while applied mathematics emphasizes the rigorous justification of the methods for approximating solutions. Differential equations play an important role in modeling virtually every physical, technical, or biological process, from celestial motion, to bridge design, to interactions between neurons. Differential equations such as those used to solve real-life problems may not necessarily be directly solvable, i.e. do not have closed form solutions. Instead, solutions can be approximated using numerical methods.

Many fundamental laws of physics and chemistry can be formulated as differential equations. In biology and economics, differential equations are used to model the behavior of complex systems. The mathematical theory of differential equations first developed together with the sciences where the equations had originated and where the results found application. However, diverse problems, sometimes originating in quite distinct scientific fields, may give rise to identical differential equations. Whenever this happens, mathematical theory behind the equations can be viewed as a unifying principle behind diverse phenomena. As an example, consider the propagation of light and sound in the atmosphere, and of waves on the surface of a pond. All of them may be described by the same second-order partial differential equation, the wave equation, which allows us to think of light and sound as forms of waves, much like familiar waves in the water. Conduction of heat, the theory of which was developed by Joseph Fourier, is governed by another second-order partial differential equation, the heat equation. It turns out that many diffusion processes, while seemingly different, are described by the same equation; the Black–Scholes equation in finance is, for instance, related to the heat equation.

Many fundamental laws of physics and chemistry can be formulated as differential equations. In biology and economics, differential equations are used to model the behavior of complex systems. The mathematical theory of differential equations first developed together with the sciences where the equations had originated and where the results found application. However, diverse problems, sometimes originating in quite distinct scientific fields, may give rise to identical differential equations. Whenever this happens, mathematical theory behind the equations can be viewed as a unifying principle behind diverse phenomena. As an example, consider the propagation of light and sound in the atmosphere, and of waves on the surface of a pond. All of them may be described by the same second-order partial differential equation, the wave equation, which allows us to think of light and sound as forms of waves, much like familiar waves in the water. Conduction of heat, the theory of which was developed by Joseph Fourier, is governed by another second-order partial differential equation, the heat equation. It turns out that many diffusion processes, while seemingly different, are described by the same equation; the Black–Scholes equation in finance is, for instance, related to the heat equation.

许多物理和化学的基本定律可以表述为微分方程。在生物学和经济学中，微分方程被用来模拟复杂系统的行为。微分方程的数学理论最初是与方程的起源和结果的应用科学一起发展起来的。然而，不同的问题，有时起源于相当不同的科学领域，可能产生相同的微分方程。每当这种情况发生时，方程后面的数学理论可以被看作是不同现象背后的统一原则。例如，考虑光和声在大气中的传播，以及池塘表面的波的传播。所有这些都可以用相同的二阶偏微分方程来描述，即波动方程，它允许我们把光和声音想象成波的形式，很像水中熟悉的波。热传导的理论是由 Joseph Fourier 提出的，由另一个二阶偏微分方程---- 热方程所支配。事实证明，许多扩散过程，虽然看起来不同，却用同一个方程来描述; 例如，金融学中的布莱克-斯科尔斯方程就与热方程有关。

许多物理和化学的基本定律可以表述为微分方程。在生物学和经济学中，微分方程被用来模拟复杂系统的行为。微分方程的数学理论最初是与方程的起源和方程解的搜索一起发展起来。然而，有时完全不同的科学领域，却可能产生相同的微分方程。每当这种情况发生时，方程后面的数学理论可以被看作是不同现象背后的统一原则。例如，考虑光和声在大气中的传播，以及池塘表面的波的传播。所有这些都可以用相同的二阶偏微分方程来描述，即波动方程，它允许我们把光和声音想象成波的形式，很像水中熟悉的波。热传导的理论是由约瑟夫.傅里叶提出的，这一过程由另一个二阶偏微分方程——热方程所支配。事实证明，许多扩散过程，虽然看起来不同，却用同一个方程来描述; 例如，金融学中的布莱克-斯科尔斯方程就与热方程有关。

The number of differential equations that have received a name, in various scientific areas is a witness of the importance of the topic. See List of named differential equations.

The number of differential equations that have received a name, in various scientific areas is a witness of the importance of the topic. See List of named differential equations.

 

 

==See also==

==See also==