# Discrete derivatives and symmetries of difference equations

@article{Levi2001DiscreteDA, title={Discrete derivatives and symmetries of difference equations}, author={Decio Levi and J. Negro and Mariano A. del Olmo}, journal={Journal of Physics A}, year={2001}, volume={34}, pages={2023-2030} }

We show with an example of the discrete heat equation that for any given discrete derivative we can construct a nontrivial Leibniz rule suitable for finding 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.

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