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Geometry-Topology Seminar

Thursday, April 8, 2021 - 4:30pm

Keaton Naff

Columbia University


University of Pennsylvania

via Zoom

The Zoom link is: This same Zoom link will apply for future talks as well. It is set to open at 4 PM so that speakers can come on early and check out their technology setups. The talks will begin at 4:30 PM. We will also stay afterwards, say from 5:30 - 6 PM to chat with one another, as an online substitute for going out to dinner with our speakers. We encourage everyone to have a nice bottle of wine at hand for that social half hour. For further information about the seminar, please contact Mona Merling (, Davi Maximo ( or Herman Gluck (

We will discuss noncollapsing in mean curvature flow and then prove a local version of the noncollapsing estimate. By combining our result with earlier work of X.-J. Wang, it follows that certain ancient convex solutions that sweep out the entire space are noncollapsed.  This is joint work with Simon Brendle.