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arXiv · 1506.05876

Needle decompositions and isoperimetric inequalities in Finsler geometry

Shin-ichi Ohta
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Abstract

Klartag recently gave a beautiful alternative proof of the isoperimetric inequalities of Levy-Gromov, Bakry-Ledoux, Bayle and E. Milman on weighted Riemannian manifolds. Klartag's approach is based on a generalization of the localization method (so-called needle decompositions) in convex geometry, inspired also by optimal transport theory. Cavalletti and Mondino subsequently generalized the localization method, in a different way more directly along optimal transport theory, to essentially non-branching metric measure spaces satisfying the curvature-dimension condition. This class in particular includes reversible (absolutely homogeneous) Finsler manifolds. In this paper, we construct needle decompositions of non-reversible (only positively homogeneous) Finsler manifolds, and show an isoperimetric inequality under bounded reversibility constants. A discussion on the curvature-dimension condition CD$(K,N)$ for $N = 0$ is also included, it would be of independent interest.

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Shin-ichi Ohta. 2015-06-19. Needle decompositions and isoperimetric inequalities in Finsler geometry. https://arxiv.org/abs/1506.05876

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