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arXiv · 2609.04371

Loss of memory in the periodic Ehrenfest model with small polyhedral scatterers

Abstract

We determine the Boltzmann--Grad limit of the Ehrenfest ``wind-tree'' model with a periodic configuration of polyhedral scatterers. The central result is a loss-of-memory effect in dimension $d\geq 3$ for a generic choice of polyhedron. This yields a Markovian limiting transport process on an extended state space and a generalised linear Boltzmann equation for the time evolution of the particle density.

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Christopher Lutsko, Jens Marklof. 2026-09-03. Loss of memory in the periodic Ehrenfest model with small polyhedral scatterers. https://arxiv.org/abs/2609.04371

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