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arXiv · 2302.14351

Torsional rigidity in random walk spaces

Jose M. Mazon·Julian Toledo
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Abstract

In this paper we study the (nonlocal) torsional rigidity in the ambient space of random walk spaces. We get the relation of the (nonlocal) torsional rigidity of a set $\Omega$ with the spectral $m$-heat content of $\Omega$, what gives rise to a complete description of the nonlocal torsional rigidity of $\Omega$ by using uniquely probability terms involving the set $\Omega$; and recover the first eigenvalue of the nonlocal Laplacian with homogeneous Dirichlet boundary conditions by a limit formula using these probability term. For the random walk in $\R^N$ associated with a non singular kernel, we get a nonlocal version of the Saint-Venant inequality, and, under rescaling we recover the classical Saint-Venant inequality. We study the nonlocal $p$-torsional rigidity and its relation with the nonlocal Cheeger constants. We also get a nonlocal version of the P\'{o}lya-Makai-type inequalities. We relate the torsional rigidity given here for weighted graphs with the torsional rigidity on metric graphs.

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Jose M. Mazon, Julian Toledo. 2023-02-28. Torsional rigidity in random walk spaces. https://arxiv.org/abs/2302.14351

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