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arXiv · 2605.00189

Local Asymptotic Patterns for Viscous Approximations of Conservation Laws

Alberto Bressan·Laura Caravenna·Wen Shen
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Abstract

Solutions to hyperbolic conservation laws can be approximated in many different ways: by vanishing viscosity, relaxations, discrete or semi-discrete numerical schemes, approximation with a nonlocal flux, etc$\ldots$ For some of these methods, general ${\bf L}^1$ convergence results are available. Aim of this paper is to understand the local behavior of these approximations, in a neighborhood of point where the hyperbolic solution has a singularity. Specifically: a point along a shock, or where two shocks interact, or where a new shock is formed. Given a sequence of $\epsilon$-approximate solutions, a general expectation is that, by a suitable local rescaling of coordinates, as $\epsilon\to 0$ a well defined limit is obtained. This corresponds to a specific ``eternal solution" (globally defined both in space and in time) to the approximating equation. Precise results this direction are here given, in the case of vanishing viscosity.

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Alberto Bressan, Laura Caravenna, Wen Shen. 2026-04-30. Local Asymptotic Patterns for Viscous Approximations of Conservation Laws. https://arxiv.org/abs/2605.00189

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