Quantitative lower bound for solutions to the Boltzmann equation in non-convex domains

Jhe-Kuan Su

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arXiv · 2505.03396

Quantitative lower bound for solutions to the Boltzmann equation in non-convex domains

Jhe-Kuan Su

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Abstract

In this article, we study the continuous mild solutions to the Boltzmann equation in a bounded spatial domain, under either angular cutoff assumption or non-cutoff assumption. Without assuming convexity of the spatial domain, we establish a Maxwellian lower bound in the cutoff case, and a weaker-than-Maxwellian lower bound for the non-cutoff case. This extends the results of \cite{Bri1,Bri2}, where the convexity of the domain was required.

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Jhe-Kuan Su. 2025-05-06. Quantitative lower bound for solutions to the Boltzmann equation in non-convex domains. https://arxiv.org/abs/2505.03396

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