Operator algebras conference in memory of Étienne Blanchard

On countable dense subgroups of the group of isometries of the Urysohn’s space.

9 avr. 2019, 15:15

50m

Bâtiment Sophie Germain, Amphi Turing (Université Paris Diderot)

Abstract

Orateur

Pierre Fima (Univ. Paris Diderot)

Description

We show that many groups acting on trees are isomorphic to a dense subgroup of the group of isometries of the bounded Urysohn’s space. This includes any free products of two infinite countable groups as well as surface groups. We also study the case of the unbounded Urysohn’s space. This is a joint work with François Le Maître, Julien Melleray and Soyoung Moon.