mean field approximation

例句：

1. 1. The mean field approximation is a useful tool for modeling complex systems.
   平均场近似是一种用于模拟复杂系统的有用工具。
2. 2.In mean field approximation, the system's behavior can be described by a single parameter.
   在平均场近似中，系统的行为可以通过一个参数来描述。
3. 3.The mean field approximation has been widely used in economics and finance to analyze the behavior of markets.
   平均场近似在经济学和金融学中被广泛使用，用于分析市场的运行行为。