非线性漂移的Fokker-Planck方程的非定态解

本文用格林函数方法讨论Fokker-Planck方程的非定态问题,将标度理论的“标度区”和“最终时区”统一考虑。在标度理论的头两个时区,所得结果与标度理论的解一致。当t→∞时,所得的非定态解趋于Fokker-Planck方程的定态解,解决了标度区分布函数在稳定点发散的问题,避免了“标度区”和“最终时区”对接的困难。关键词：

TIME DEPENDENT SOLUTION OF FOKKER-PLANCK EQUATION WITH NON-LINEAR DRIFT FORCE

A new approach of the O-expansion of the Green's function is empoyed to study the time dependent problem of the Fokker-Planck equation. The scaling region and the final region in the scaling theory is unified to a single region. As t→∞ the time dependent solution approaches the stationary solution of the Fokker-Planck equation. The difficulty of matching the last two time regions in the scaling theory is then avoided.