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arXiv · 2501.06542

Revisiting ancient noncollapsed flows in $\mathbb{R}^3$

Kyeongsu Choi·Robert Haslhofer
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Abstract

In this short paper, we give a new proof of the classification theorem for noncompact ancient noncollapsed flows in $\mathbb{R}^3$ originally due to Brendle-Choi (Inventiones 2019). Our new proof directly establishes selfsimilarity by combining the fine neck theorem from our joint work with Hershkovits and the rigidity case of Hamilton's Harnack inequality.

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Kyeongsu Choi, Robert Haslhofer. 2025-01-11. Revisiting ancient noncollapsed flows in $\mathbb{R}^3$. https://arxiv.org/abs/2501.06542

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