非线性随机微分方程:一种重新规范化组方法,用于直接计算时刻
Prasun Sarkar1, Deb Shankar Ray1
1Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
Physical review. E
|February 7, 2025
概括
本研究引入了一种重新规范化组 (RG) 方法,用于直接计算非线性随机微分方程 (SDEs) 的平均值和方差. 该方法揭示了噪声和非线性如何影响动态系统的频率和稳定性.
科学领域:
- 非线性动力学是一种非线性动力学.
- 随机过程是指随机的过程.
- 统计物理学的统计物理.
背景情况:
- 解决非线性随机微分方程 (SDEs) 通常依赖于福克-普朗克方程.
- 对非线性SDEs的直接分析解决方案具有挑战性.
研究的目的:
- 开发一种直接计算方法,用于非线性SDEs的平均值和方差.
- 用重新规范化组 (RG) 技术研究非线性和噪声对动态系统属性的影响.
主要方法:
- 应用重新规范化组 (RG) 技术.
- 确定性和随机时间尺度的分离.
- 对振幅和相位的RG流程方程的分析.
主要成果:
- 提出了一种直接方法来计算非线性SDEs的平均值和方差.
- 非线性和噪声对系统的频率进行了校正.
- 确定了外部噪声下的极限周期的稳定性值.
结论:
- RG方法为非线性SDEs提供了福克-普朗克描述的替代方案.
- 非线性和噪声的相互作用显著影响系统动态.
- 开发的理论与数值模拟相一致.
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