Speaker
Alexis Marchand
(Instytut Matematyczny Polskiej Akademii Nauk)
Description
(Joint work with Piotr Nowak.) Bounded cohomology is a functional-analytic variant of group cohomology. Despite its many connections with geometry and topology, it can be a mysterious object. This talk will be about the property of bounded cohomology being Hausdorff. We will explain how this property can be read in asymptotic cohomology, yet another cohomology theory that was introduced recently to study stability properties of groups. This makes use of ultraproduct techniques invented by Bader and Sauer in the context of property (T), and that we will explain.
Author
Alexis Marchand
(Instytut Matematyczny Polskiej Akademii Nauk)