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arXiv · 2005.01222

Isometric immersions of RCD spaces

Shouhei Honda
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Abstract

We prove that if an RCD space has a regular isometric immersion in a Euclidean space, then the immersion is a locally bi-Lipschitz embedding map. This result leads us to prove that if a compact non-collapsed RCD space has an isometric immersion in a Euclidean space via an eigenmap, then the eigenmap is a locally bi-Lipschitz embedding map to a sphere, which generalizes a fundamental theorem of Takahashi in submanifold theory to a non-smooth setting. Applications of these results include a topological sphere theorem and topological finiteness theorems, which are new even for closed Riemannian manifolds.

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Shouhei Honda. 2020-05-04. Isometric immersions of RCD spaces. https://arxiv.org/abs/2005.01222

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