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arXiv · 2407.20159

If a Minkowski billiard is projective, it is the standard billiard

Alexey Glutsyuk·Vladimir S. Matveev
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Abstract

In the recent paper arXiv:2405.13258, the first author of this note proved that if a billiard in a convex domain in $\mathbb{R}^n$ is simultaneously projective and Minkowski, then it is the standard Euclidean billiard in an appropriate Euclidean structure. The proof was quite complicated and required high smoothness. Here we present a direct simple proof of this result which works in $C^1$-smoothness. In addition we prove the semi-local and local versions of the result

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Alexey Glutsyuk, Vladimir S. Matveev. 2024-07-29. If a Minkowski billiard is projective, it is the standard billiard. https://doi.org/10.4213/sm10182e

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