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arXiv · 1905.05572

1st eigenvalue pinching for convex hypersurfaces in a Riemannian manifold

Yingxiang Hu·Shicheng Xu
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Abstract

Let $M^n$ be a closed convex hypersurface lying in a convex ball $B(p,R)$ of the ambient $(n+1)$-manifold $N^{n+1}$. We prove that, by pinching Heintze-Reilly's inequality via sectional curvature upper bound of $B(p,R)$, 1st eigenvalue and mean curvature of $M$, not only $M$ is Hausdorff close and almost isometric to a geodesic sphere $S(p_0,R_0)$ in $N$, but also its enclosed domain is $C^{1,α}$-close to a geodesic ball of constant curvature.

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Yingxiang Hu, Shicheng Xu. 2019-05-14. 1st eigenvalue pinching for convex hypersurfaces in a Riemannian manifold. https://arxiv.org/abs/1905.05572

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