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arXiv · 2110.02254

On the fundamental group of non-collapsed ancient Ricci flows

Richard H. Bamler
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Abstract

We show that any manifold admitting a non-collapsed, ancient Ricci flow must have finite fundamental group. This generalizes what was known for $\kappa$-solutions in dimensions 2, 3. We furthermore show that this fundamental group must be a quotient of the fundamental group of the regular part of any tangent flow at infinity.

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Richard H. Bamler. 2021-10-05. On the fundamental group of non-collapsed ancient Ricci flows. https://arxiv.org/abs/2110.02254

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