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arXiv · 1702.00740

New characterizations of Ricci curvature on RCD metric measure spaces

Bang-Xian Han
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Abstract

We prove that on a large family of metric measure spaces, if the $L^p$-gradient estimate for heat flows holds for some $p>2$, then the $L^1$-gradient estimate also holds. This result extends Savar\'e's result on metric measure spaces, and provides a new proof to von Renesse-Sturm theorem on smooth metric measure spaces. As a consequence, we propose a new analysis object based on Gigli's measure-valued Ricci tensor, to characterize the Ricci curvature of ${\rm RCD}$ space in a local way. The argument is a new iteration technique based on non-smooth Bakry-\'Emery theory, which is a new method to study the curvature dimension condition of metric measure spaces.

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BibTeXRIS

Bang-Xian Han. 2017-02-02. New characterizations of Ricci curvature on RCD metric measure spaces. https://doi.org/10.3934/dcds.2018214

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