A non-trivial conservation law with a trivial characteristic

Kostya Druzhkov

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arXiv · 2502.11502

A non-trivial conservation law with a trivial characteristic

Kostya Druzhkov

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Abstract

We show that the conservation law of the overdetermined system $u_t - 4u_x^3 - u_{xxx} = 0$, $u_y = 0$, associated with the characteristic $(u_{xy}, 0)$, is non-trivial despite the characteristic vanishing on the system.

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Kostya Druzhkov. 2025-02-17. A non-trivial conservation law with a trivial characteristic. https://arxiv.org/abs/2502.11502

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