Inkang Kim - Positivity of Gromov simplicial volume of non-positively curved 4-manifolds

mardi 6 janv. 2026, 14:00 → 15:00 Europe/Paris

435 (UMPA)

We show the positivity of Gromov simplicial volume for closed, non-positively curved 4-manifolds with non-zero Euler number, and consequently with negative Ricci curvature. This has been a long-standing open question by Gromov.
We use the Gauss-Bonnet theorem for Riemannian simplices by Allendoerfer and Weil.  This is a joint work with X. Wan.