05/18: Or Landesberg
Horospherically invariant measures on geometrically infinite quotients
Abstract: We consider a locally finite (Radon) measure on 
invariant under a horospherical subgroup of where 
is a discrete, but not necessarily geometrically finite, subgroup. We show that whenever the measure does not admit any additional invariance properties then it must be supported on a set of points with geometrically degenerate trajectories under the corresponding contracting 1-parameter diagonalizable flow (geodesic flow). We deduce measure classification results. One such result in the context of finitely generated Kleinian groups in 
will be highlighted. Most of the talk will be based on joint work with Elon Lindenstrauss.
invariant under a horospherical subgroup of where is a discrete, but not necessarily geometrically finite, subgroup. We show that whenever the measure does not admit any additional invariance properties then it must be supported on a set of points with geometrically degenerate trajectories under the corresponding contracting 1-parameter diagonalizable flow (geodesic flow). We deduce measure classification results. One such result in the context of finitely generated Kleinian groups in will be highlighted. Most of the talk will be based on joint work with Elon Lindenstrauss.