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arXiv · 2606.08556

From generalized Poincar\'e to Poincar\'e-Sobolev inequalities via self-improving methods

Abstract

We establish several improvements to the main results of [PR19] and [CP21], refining the seminal self-improving method for generalized Poincar\'e inequalities from [FPW98, MP98]. These results, together with various related applications, stem from a general self-improving property for functions satisfying the local inequality $$\frac{1}{|Q|}\int_Q |f(x)-f_Q|\,dx \le a(Q)$$ for all cubes $Q\subset\mathbb{R}^n$. The functional $a$ is assumed to obey a specific discrete geometric summability condition. By restricting our focus to axis-parallel cubes in $\mathbb{R}^n$, this geometric setting allows us to obtain sharper estimates than those available in more general metric measure spaces.

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Alejandro Claros, Carlos Pérez, Linfei Zheng. 2026-06-07. From generalized Poincar\'e to Poincar\'e-Sobolev inequalities via self-improving methods. https://arxiv.org/abs/2606.08556

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