Perelman's Entropies for Manifolds with conical Singularities

Klaus Kroencke; Boris Vertman

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arXiv · 1902.02097

Perelman's Entropies for Manifolds with conical Singularities

Klaus Kroencke·Boris Vertman

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Abstract

In this paper we discuss Perelman's Lambda-functional, Perelman's Ricci shrinker entropy as well as the Ricci expander entropy on a class of manifolds with isolated conical singularities. On such manifolds, a singular Ricci de Turck flow preserving the isolated conical singularities exists by our previous work. We prove that the entropies are monotone along the singular Ricci de Turck flow. We employ these entropies to show that in the singular setting, Ricci solitons are gradient and that steady or expanding Ricci solitons are Einstein.

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Klaus Kroencke, Boris Vertman. 2019-02-06. Perelman's Entropies for Manifolds with conical Singularities. https://arxiv.org/abs/1902.02097

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