A note on Hang-Wang's hemisphere rigidity theorem

Mijia Lai

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arXiv · 1905.01870

A note on Hang-Wang's hemisphere rigidity theorem

Mijia Lai

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Abstract

Let $(M,g)$ be a compact manifold with boundary and $Ric_g\geq (n-1)g$, Hang and Wang proved that $(M,g)$ is isometric to the standard hemisphere if $\partial M$ is convex and isometric to $\mathbb{S}^{n-1}(1)$. We prove some rigidity theorems when $\partial M $ is isometric to a product manifold where one factor is the standard sphere.

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Mijia Lai. 2019-05-06. A note on Hang-Wang's hemisphere rigidity theorem. https://arxiv.org/abs/1905.01870

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