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arXiv · 1901.02863

Nonconvex Surfaces which Flow to Round Points

Alexander Mramor·Alec Payne
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Abstract

In this article, we extend Huisken's theorem that convex surfaces flow to round points by mean curvature flow. We construct certain classes of mean convex and non-mean convex hypersurfaces that shrink to round points and use these constructions to create pathological examples of flows. We find a sequence of flows that exist on a uniform time interval, have uniformly bounded diameter, and shrink to round points, yet the sequence of initial surfaces has no subsequence converging in the Gromov-Hausdorff sense. Moreover, we find a sequence of flows which all shrink to round points, yet the initial surfaces converge to a space-filling surface. Also constructed are surfaces of arbitrarily large area which are close in Hausdorff distance to the round sphere yet shrink to round points.

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Alexander Mramor, Alec Payne. 2021-05-13. Nonconvex Surfaces which Flow to Round Points. https://arxiv.org/abs/1901.02863

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