摘要
先给出了含有一个任意函数的线性波动方程的古典和势对称的完全分类.然后,在此基础上给出了含有两个任意函数的一类非线性波动方程的两种情形势对称分类,得到了该方程的新势对称.在处理对称群分类问题的难点-求解确定方程组时我们提出了微分形式吴方法算法,克服了以往难于处理的困难.在整个计算过程中反复使用了吴方法,吴方法起到了关键的作用.
In this paper, a complete classical and potential symmetry classification is obtained for a linear wave equation containing an arbitrary function. Then based on the results, two kinds of potential symmetry classifications, through two equivalent equations, are determined for a scalar nonlinear wave equation with two arbitrary functions. As a result, new potential symmetries of this equation are given. The most difficult problem existing in current calculations for symmetry group classifications, i.e., solving over-determined determining equations, is overcomed by using differential form Wu＇s method algorithm. The method is used repeatly in whole huge calculations and plays key rule.
出处
《系统科学与数学》
CSCD
北大核心
2009年第3期389-411,共23页
Journal of Systems Science and Mathematical Sciences
基金
国家自然科学基金(10461005)
内蒙古自然科学基金重点(200607010103)
上海市教委支出预算(2008069)
和教育部博士点基金(20070128001)资助项目.
关键词
非线性波动方程
对称分类
势对称
微分形式吴方法
Nonlinear wave equation, symmetry classification, potential symmetry, differential form Wu＇s method.
