A conference on the interaction of ergodic theory, differential geometry and the theory of Lie
Groups was held at the Mathematical Sciences Research Institute from May 24 to June 1 …

Rigidity and cocycles for ergodic actions of semi-simple lie groups Page 1 S6minaire
BOURBAKI 32e annie, 1979/80, n 559 559-O1 Juin 1980 RIGIDITY AND COCYCLES FOR …

In this paper we discuss the use of dynamical and ergodic-theoretic ideas and methods to
solve some long-standing problems originating from Lie groups and number theory. These …

1. Introduction. The point of this paper is to study the low dimensional cohomology theory of
ergodic actions of semisimple Lie groups and their lattice subgroups. The rigidity theorem for …

An important problem in ergodic theory is to determine when the restriction to a subgroup of
an ergodic action of a group is still ergodic. Classical results concerning the ergodicity of …

This paper studies the ergodic theory at infinity of an arbitrary discrete isometry group
$\Gamma $ acting on any Hadamard manifold $ H $ of pinched variable negative curvature …

Let Γ be a finitely-generated group, M a compact manifold and φ: Γ x M-» M a enaction of Γ
on M. Let TZ (Γ^ Diff1 (M)) denote the variety of representations of Γ into Diff1 (M). It is a …

The aim of this paper is to prove an analogue of the strong rigidity theorems for lattices in
semisimple Lie groups of Mostow and Margulis in the context of ergodic actions of …

In a series of recent papers [21-23], we have examined certain rigidity properties of actions
of semisimple Lie groups and their discrete subgroups on compact manifolds. In these …

In 1974, using techniques of ergodic theory, Margulis proved superrigidity for lattices in
higher R-rank semisimple Lie groups. While superrigidity was known to fail for lattices in …