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arXiv · 1009.3004

On the speed of approach to equilibrium for a collisionless gas

Kazuo Aoki·François Golse
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Abstract

We investigate the speed of approach to Maxwellian equilibrium for a collisionless gas enclosed in a vessel whose wall are kept at a uniform, constant temperature, assuming diffuse reflection of gas molecules on the vessel wall. We establish lower bounds for potential decay rates assuming uniform $L^p$ bounds on the initial distribution function. We also obtain a decay estimate in the spherically symmetric case. We discuss with particular care the influence of low-speed particles on thermalization by the wall.

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Kazuo Aoki, François Golse. 2010-09-15. On the speed of approach to equilibrium for a collisionless gas. https://doi.org/10.3934/krm.2011.4.87

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