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arXiv · 2107.00335

Area and boundary length of surfaces diffeomorphic to annuli

Tsz-Kiu Aaron Chow
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Abstract

In this paper, we give a proof to a statement in Perelman's paper for finite extinction time of Ricci flow. Our proof draws on different techniques from the one given in Morgan-Tian's exposition and is extrinsic in nature, which relies on the co-area formula instead of the Gauss-Bonnet theorem, and is potentially generalizable to higher dimensions.

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Tsz-Kiu Aaron Chow. 2021-07-01. Area and boundary length of surfaces diffeomorphic to annuli. https://arxiv.org/abs/2107.00335

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