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Can embedding problems be used to distinguish S^4 from other (possible) homotopy 4-spheres?

June 4, 2024 @ 4:00 pm - 5:00 pm

Speaker: Michael Freedman, Harvard CMSA

Title: Can embedding problems be used to distinguish S^4 from other (possible) homotopy 4-spheres?

Abstract: There are approaches in the literature (using Khovanov homology) to detecting a homotopy 4-sphere, via the 4-ball genus of knots. I’d like to suggest moving from surfaces to 3-manifolds, that is approaching the problem by considering the which closed 3-manifolds embed.  Embedding in the actual S^4 implies a curious condition on the possible Heegaard diagrams for the 3-manifold. I’ll explain this condition and speculate on how it might be exploited.

Details

Date:
June 4, 2024
Time:
4:00 pm - 5:00 pm
Series:
Event Category:

Venue

CMSA
20 Garden Street
Cambridge, MA 02138 United States
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