Speaker: Marco Antei
Date: January 21, 2010
Affiliation: University of Lille, France

Abstract: Let $X$ be a scheme over a field $k$ and $f:Y\to X$ an essentially finite morphism. We construct a "Galois closure" of $f$, i.e. the smallest possible torsor dominating it. As an application we construct the Galois closure of towers of torsors. (Work in collaboration with Michel Emsalem).