Speaker: Federico Scavia
Affiliation: Université Sorbonne Paris Nord
Title of Talk: Generically trivial torsors under algebraic groups
Date: February 02, 2026
Time: 11:00:00 Hours
Venue: Guest House Seminar Room

Abstract: I will discuss the recent proof, joint with A. Bouthier and K. Cesnavicius, of the Grothendieck-Serre conjecture for constant groups: for a field $k$, a smooth $k$-group scheme $G$ and a smooth $k$-variety $X$, every generically trivial $G$-torsor over $X$ trivializes Zariski semilocally on $X$. This was known when $G$ is reductive or when $k$ is perfect.