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Precise asymptotics of the Ricci flow neckpinch

Sigurd Angenent·Dan Knopf
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Abstract

The best known finite-time local Ricci flow singularity is the neckpinch, in which a proper subset of the manifold becomes geometrically close to a portion of a shrinking cylinder. In this paper, we prove precise asymptotics for rotationally symmetric Ricci flow neckpinches. We then compare these rigorous results with formal matched asymptotics for fully general neckpinch singularities.

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Sigurd Angenent, Dan Knopf. 2005-11-09. Precise asymptotics of the Ricci flow neckpinch. https://arxiv.org/abs/math/0511247

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