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arXiv · 2304.02681

Weighted fractional Poincar\'e inequalities via isoperimetric inequalities

Abstract

Our main result is a weighted fractional Poincar\'e-Sobolev inequality improving the celebrated estimate by Bourgain-Brezis-Mironescu. This also yields an improvement of the classical Meyers-Ziemer theorem in several ways. The proof is based on a fractional isoperimetric inequality and is new even in the non-weighted setting. We also extend the celebrated Poincar\'e-Sobolev estimate with $A_p$ weights of Fabes-Kenig-Serapioni by means of a fractional type result in the spirit of Bourgain-Brezis-Mironescu. Examples are given to show that the corresponding $L^p$-versions of weighted Poincar\'e inequalities do not hold for $p>1$.

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Kim Myyryläinen, Carlos Pérez, Julian Weigt. 2023-04-05. Weighted fractional Poincar\'e inequalities via isoperimetric inequalities. https://arxiv.org/abs/2304.02681

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