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arXiv · 2607.19878

Relative entropy analysis of the Jin-Xin model: Theory and Numerics

Christina Mahmoud
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Abstract

This work studies the linear Jin-Xin relaxation model by means of the relative entropy method, both at the continuous and fully discrete levels. Under the strict subcharacteristic condition, we obtain an O($\epsilon$) estimate for the convergence toward the equilibrium transport equation. We then develop discrete relative entropy estimates for a Lie splitting scheme and an asymptotic preserving staggered scheme. A fixed-time analysis further explains the O($\epsilon$^2 ) behavior observed in the strongly stiff regime and the transition occurring when $\epsilon$ becomes comparable to the time step.

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Christina Mahmoud. 2026-07-22. Relative entropy analysis of the Jin-Xin model: Theory and Numerics. https://arxiv.org/abs/2607.19878

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