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arXiv · 2011.07244

A Blaschke-Lebesgue Theorem for the Cheeger constant

Antoine Henrot·Ilaria Lucardesi
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Abstract

In this paper we prove a new extremal property of the Reuleaux triangle: it maximizes the Cheeger constant among all bodies of (same) constant width. The proof relies on a fine analysis of the optimality conditions satisfied by an optimal Reuleaux polygon together with an explicit upper bound for the inradius of the optimal domain. As a possible perspective, we conjecture that this maximal property of the Reuleaux triangle holds for the first eigenvalue of the $p$-Laplacian for any $p\in (1,+\infty)$ (the current paper covers the case $p=1$ whereas the case $p=+\infty$ was already known).

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Antoine Henrot, Ilaria Lucardesi. 2020-11-14. A Blaschke-Lebesgue Theorem for the Cheeger constant. https://arxiv.org/abs/2011.07244

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