Buondì, Con colpevolissimo ritardo vi annuncio il seminario di geometria di oggi, che sarà alle 16 in aula N. Siete tutti invitati. A presto Bruno Martelli Aspherical 4-manifolds with positive Euler characteristic – Pietro Capovilla (SNS, Pisa) Monday, Dec 15, 2025 16:00 — 17:00 Aula N (Polo Fibonacci, University of Pisa) Seminars <https://www.dm.unipi.it/en/en/seminars>, Geometry Seminar <https://www.dm.unipi.it/en/en/seminars/?category=653b522f8f0af760bdc42729> I will present an explicit construction of closed oriented aspherical smooth 4-manifolds realizing every non-negative Euler characteristic. This family of manifolds saturates Hopf-Thurston conjecture on the Euler characteristic of aspherical manifolds, as well as Gromov-Lück inequality regarding their geography.