Penn Arts & Sciences Logo

Geometry-Topology Seminar

Thursday, December 5, 2024 - 3:30pm

Søren Galatius

Columbia

Location

University of Pennsylvania

DRL 3W2

I will recall Quillen's plus construction and its universal property in homotopy theory.  The plus construction has an analogue for manifolds, introduced earlier by Kervaire in his study of homology spheres.  The universal property of the plus construction also has an analogue in the manifold setting, established in joint work with Randal-Williams (arXiv:2308.15607).  Time permitting, I will discuss an application to automorphism groups of contractible manifolds, generalizing the Alexander trick.

Other Events on This Day