Séminaire d'algèbre et de géométrie du 22-11-2024

Exposé de Ivo Dell'Ambrogio

Le 22-11-2024 à 14:25, en P108 et en ligne.

An introduction to Mackey 2-functors

I will present an axiomatic framework for “equivariant mathematics” introduced in 2020 in collaboration with Paul Balmer. The point is to formalize abelian or triangulated categories “of equivariant objects” (e.g. linear representations) for finite groups, together with the restriction and induction functors between these categories. Among applications to date, our theory allowed us to generalize certain classical results from modular representation theory (e.g. the Green correspondence of indecomposable representations) and group cohomology (e.g. the stable elements formula of Cartan-Eilenberg) to geometric and topological contexts.