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arXiv · 1211.6354

An equation linking $\mathscr{W}$-entropy with reduced volume

Abstract

$\mathscr{W}$-entropy and reduced volume for the Ricci flow were introduced by Perelman, which had proved their importance in the study of the Ricci flow. L. Ni studied the analogous concepts for the linear heat equation on the static manifolds, and established an equation which links the large time behavior of these two. Due to the surprising similarity between those concepts in the Ricci flow and the linear heat equation, a natural question whether such equation holds for the Ricci flow ancient solution was asked by L. Ni. In this paper, we gave an alternative proof to L. Ni's original equation based on a new method. And following the same philosophy of this method, we answer L. Ni's question positively for Type I $\kappa$-solutions of the Ricci flow.

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Guoyi Xu. 2012-11-27. An equation linking $\mathscr{W}$-entropy with reduced volume. https://doi.org/10.1515/crelle-2014-0136

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