Notes on Ricci flows with collapsing initial data (I): Distance distortion

Shaosai Huang

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arXiv · 1808.07394

Notes on Ricci flows with collapsing initial data (I): Distance distortion

Shaosai Huang

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Abstract

In this note, we prove a uniform distance distortion estimate for Ricci flows with uniformly bounded scalar curvature, independent of the lower bound of the initial $\mu$-entropy. Our basic principle tells that once correctly renormalized, the metric-measure quantities obey similar estimates as in the non-collapsing case; espeically, the lower bounds of the renormalized heat kernel, observed on a scale comparable to the initial diameter, matches with the lower bound of the renormalized volume ratio, giving the desired distance distortion estimate.

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Shaosai Huang. 2018-08-22. Notes on Ricci flows with collapsing initial data (I): Distance distortion. https://arxiv.org/abs/1808.07394

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