Calculus of Variations and Geometric Measure Theory

L. Brasco

Beyond Cheeger's constant

created by brasco on 05 Apr 2024
modified on 08 Apr 2024

[BibTeX]

Preprint

Inserted: 5 apr 2024
Last Updated: 8 apr 2024

Pages: 33
Year: 2024
Notes:

In memory of Rodolfo Boschi


Abstract:

The Cheeger constant of an open set of the Euclidean space is defined by minimizing the ratio ``perimeter over volume'', among all its smooth compactly contained subsets. We consider a natural variant of this problem, where the volume of admissible sets is raised to any positive power. We show that for {\it sublinear} powers, all these generalized Cheeger constants are equivalent to the standard one, by means of a universal two-sided estimate. We also show that this equivalence breaks down for {\it superlinear} powers. In this case, some weird phenomena appear. We finally consider the case of convex planar sets and prove an existence result, under optimal assumptions.

Keywords: convex sets, Sobolev-Poincaré Inequalities, Inradius, Cheeger's constant


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