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arXiv · 1003.2116

Localization and Tensorization Properties of the Curvature-Dimension Condition for Metric Measure Spaces

Kathrin Bacher·Karl-Theodor Sturm
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Abstract

This paper is devoted to the analysis of metric measure spaces satisfying locally the curvature-dimension condition CD(K,N) introduced by the second author and also studied by Lott & Villani. We prove that the local version of CD(K,N) is equivalent to a global condition CD*(K,N), slightly weaker than the (usual, global) curvature-dimension condition. This so-called reduced curvature-dimension condition CD*(K,N) has the local-to-global property. We also prove the tensorization property for CD*(K,N). As an application we conclude that the fundamental group of a metric measure space (M,d,m) is finite whenever it satisfies locally the curvature-dimension condition CD(K,N) with positive K and finite N.

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Kathrin Bacher, Karl-Theodor Sturm. 2010-03-10. Localization and Tensorization Properties of the Curvature-Dimension Condition for Metric Measure Spaces. https://arxiv.org/abs/1003.2116

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