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Discrete derivatives and symmetries of difference equations

D. Levi·J. Negro·M. A. del Olmo
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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.

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D. Levi, J. Negro, M. A. del Olmo. 2000-10-26. Discrete derivatives and symmetries of difference equations. https://doi.org/10.1088/0305-4470%2F34%2F10%2F306

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