Harmonic maps and random walks on countable groups (Hiroyasu IZEKI, Keio University)

26.03.2024 10:30

Let Y be a proper CAT(0) space and G a countable group acting on Y. The main result of this talk says that if the action of G does not fix a point in the boundary at infinity of Y and its rate of escape is zero, then there is a flat subspace in Y left invariant by the action of G. The key ingredient of the proof is an equivariant harmonic map from G into Y. Some consequences of this result will be also discussed.

Lieu

Bâtiment: Conseil Général 7-9

Room 1-05, Tuesday 26.03.24, Séminaire "Groupes et Géométrie"

entrée libre