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arXiv · 2211.02747

The Grushin hemisphere as a Ricci limit space with curvature $\ge 1$

Jiayin Pan
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Abstract

The Grushin sphere is an almost-Riemannian manifold that degenerates along its equator. We construct a sequence of Riemannian metrics on a sphere $S^{m+n}$ with $Ric\ge 1$ such that its Gromov-Hausdorff limit is the $n$-dimensional Grushin hemisphere.

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Jiayin Pan. 2022-11-04. The Grushin hemisphere as a Ricci limit space with curvature $\ge 1$. https://doi.org/10.1090/bproc%2F160

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