Bruno Duchesne

Superrigidity in infinite dimension and finite rank via harmonic maps

We prove geometric superrigidity for actions of cocompact lattices in semisimple Lie groups of higher rank on infinite dimensional Riemannian manifolds of nonpositive curvature and finite telescopic dimension.

Furstenberg maps for CAT(0) targets of finite telescopic dimension

We consider actions of locally compact groups

Amenable invariant random subgroups

G

Group actions on dendrites and curves

on certain CAT(0) spaces

Structural properties of dendrite groups

X

Geometric density for invariant random subgroups of groups acting on CAT(0) spaces

by isometries. The CAT(0) spaces we consider have finite dimension at large scale. In case

Almost algebraic actions of algebraic groups and applications to algebraic representations

B

Boundary maps and maximal representations on infinite dimensional Hermitian symmetric spaces

is a

A new lattice invariant for lattices in totally disconnected locally compact groups.

G

Kaleidoscopic groups: permutation groups constructed from dendrite homeomorphisms

-boundary, that is a measurable