Discrete derivatives and symmetries of difference equations
arXiv:nlin/0010044 · doi:10.1088/0305-4470/34/10/306
Abstract
We show on the example of the discrete heat equation that for any given discrete derivative we can construct a nontrivial Leibniz rule suitable to find the symmetries of discrete equations. In this way we obtain a symmetry Lie algebra, defined in terms of shift operators, isomorphic to that of the continuous heat equation.
submitted to J.Phys. A 10 Latex pages