Global Stability of the Boltzmann Equation for a Polyatomic Gas with Initial Data Allowing Large Oscillations

Gyounghun Ko; Sung-jun Son

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arXiv · 2407.13192

Global Stability of the Boltzmann Equation for a Polyatomic Gas with Initial Data Allowing Large Oscillations

Gyounghun Ko·Sung-jun Son

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Abstract

In this paper, we consider the Boltzmann equation for a polyatomic gas. We establish that the mild solution to the Boltzmann equation on the torus is globally well-posed, provided the initial data that satisfy bounded velocity-weighted $L^{\infty}$ norm and the smallness condition on the initial relative entropy. Furthermore, we also study the asymptotic behavior of solutions, converging to the global Maxwellian with an exponential rate. A key point in the proof is to develop the pointwise estimate on the gain term of non-linear collision operator for Gr\"{o}nwall's argument.

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Gyounghun Ko, Sung-jun Son. 2024-07-18. Global Stability of the Boltzmann Equation for a Polyatomic Gas with Initial Data Allowing Large Oscillations. https://arxiv.org/abs/2407.13192

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