Geometry Seminar: Aditya Kumar (Johns Hopkins)

GeoTop Geometry Seminar (Geometric Analysis)

Time: 16:15-17:15, Wednesday, January 8th, 2025

Speaker: Aditya Kumar (Johns Hopkins U)

Title: Positive scalar curvature and exotic structures on simply connected four manifolds.

Abstract: Several results involving positive scalar curvature (PSC) are false in dimension four due to counterexamples based on Seiberg-Witten invariants. To sidestep this, we will consider smooth four manifolds admitting a PSC metric only up to a homeomorphism. Reformulated this way, we establish Gromov's band width inequality conjecture and Rosenberg's S^1 stability conjecture for simply connected four manifolds up to homeomorphism. Both results are otherwise false. Based on joint work with Balarka Sen.

Zoom: Please ask Niels Martin Møller for the URL.