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arXiv · 2107.01419

A uniform Sobolev inequality for ancient Ricci flows with bounded Nash entropy

Pak-Yeung Chan·Zilu Ma·Yongjia Zhang
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Abstract

This note is a continuation of [CMZ21]. We shall show that an ancient Ricci flow with uniformly bounded Nash entropy must also have uniformly bounded $\nu$-functional. Consequently, on such an ancient solution there are uniform logarithmic Sobolev and Sobolev inequalities. We emphasize that the main theorem in this paper is true so long as the theory in [Bam20c] is valid, and in particular, when the underlying manifold is closed.

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Pak-Yeung Chan, Zilu Ma, Yongjia Zhang. 2021-07-03. A uniform Sobolev inequality for ancient Ricci flows with bounded Nash entropy. https://arxiv.org/abs/2107.01419

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