Computer Algebra Algorithms and Routines for the Computation of Conservation Laws and Fixing of Gauge in Differential Expressions
نویسندگان
چکیده
Three different approaches for the determination of conservation laws of differential equations are presented. For three corresponding REDUCE computer algebra programs CONLAW1/2/3 the necessary subroutines are described. One of them simplifies general solutions of overdetermined PDE systems so that all remaining free functions and constants correspond to independent conservation laws. It determines redundant functions and constants in differential expressions and is equally useful for the determination of symmetries or the fixing of gauge freedom in differential expressions.
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عنوان ژورنال:
- J. Symb. Comput.
دوره 27 شماره
صفحات -
تاریخ انتشار 1999