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The average length of a trajectory in a certain billiard in a flat two-torus

Florin P. Boca·Radu N. Gologan·Alexandru Zaharescu
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Abstract

We remove a small disc from the flat two-dimensional torus and consider a point-like particle that starts moving from the center of the disc with linear trajectory. We provide asymptotic estimates for the moments of the first exit time, with respect to the velocity, when the radius of the disc tends to zero.

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Florin P. Boca, Radu N. Gologan, Alexandru Zaharescu. 2003-12-23. The average length of a trajectory in a certain billiard in a flat two-torus. https://arxiv.org/abs/math/0110208

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