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arXiv · 2103.11344

Some topological results of Ricci limit spaces

Jiayin Pan·Jikang Wang
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Abstract

We study the topology of a Ricci limit space $(X,p)$, which is the Gromov-Hausdorff limit of a sequence of complete $n$-manifolds $(M_i, p_i)$ with $\mathrm{Ric}\ge -(n-1)$. Our first result shows that, if $M_i$ has Ricci bounded covering geometry, i.e. the local Riemannian universal cover is non-collapsed, then $X$ is semi-locally simply connected. In the process, we establish a slice theorem for isometric pseudo-group actions on a closed ball in the Ricci limit space. In the second result, we give a description of the universal cover of $X$ if $M_i$ has a uniform diameter bound.

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Jiayin Pan, Jikang Wang. 2021-03-21. Some topological results of Ricci limit spaces. https://arxiv.org/abs/2103.11344

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