MKdV 和FPU 方程的李点对称

摘要

In this paper, we discuss the Lie symmetry of discrete differential equations. By means of the prolonging method and the commuting flows method, we obtain the Lie symmetry of some important different equations and differential-difference equations, which extends the results in the case of continuous differential equations.%本文研究了离散微分方程的李对称问题。利用差分方程的延拓方法和交换流方法，我们求得了若干重要的差分方程、微分差分方程的李对称，推广了对称性分析法在连续微分方程讨论时的结果。