Non-uniqueness of admissible weak solutions to the two-dimensional barotropic compressible Euler system with contact discontinuities

Kotaro Horimoto

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arXiv · 2603.23921

Non-uniqueness of admissible weak solutions to the two-dimensional barotropic compressible Euler system with contact discontinuities

Kotaro Horimoto

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Abstract

This paper is concerned with the Riemann problem for the two-dimensional barotropic compressible Euler system with a general strictly increasing pressure law. By means of convex integration, the existence of infinitely many admissible weak solutions is established for certain Riemann initial data for which the corresponding one-dimensional self-similar solution consists solely of a contact discontinuity.

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Kotaro Horimoto. 2026-03-25. Non-uniqueness of admissible weak solutions to the two-dimensional barotropic compressible Euler system with contact discontinuities. https://arxiv.org/abs/2603.23921

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