Stochastically perturbed billiards: fingerprints of chaos and universality classes

Roberto Artuso; Matteo Burlo

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arXiv · 2605.11849

Stochastically perturbed billiards: fingerprints of chaos and universality classes

Roberto Artuso·Matteo Burlo

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Abstract

Billiards tables - a minimal model for particles moving in a confined region - are known to present classical (and quantum) different features according to their shape, ranging from strongly chaotic to integrable dynamics. Here we consider the role of a stochastic perturbation of the elastic reflection law, and show that while chaotic billiards maintain their key statistical feature, the behaviour for integrable billiard tables is completely different: it can be linked, for tiny perturbations, to Evans stochastic billiard, where at each collision the reflected angle is a uniformly distributed stochastic variable on $(-\pi/2,\pi/2$). The resulting spatial stationary measure has peculiar aspects, like being typically non uniform along the boundary, differently from any chaotic billiard table.

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Roberto Artuso, Matteo Burlo. 2026-05-12. Stochastically perturbed billiards: fingerprints of chaos and universality classes. https://arxiv.org/abs/2605.11849

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