We establish new results on the weak containment of quasi-regular and Koopman representations of a second countable locally compact group GG associated with nonsingular GG-spaces. We deduce that any two boundary representations of a hyperbolic locally ...
We generalize the fixed-point property for discrete groups acting on convex cones given by Monod in [23] to topological groups. At first, we focus on describing this fixed-point property from a functional point of view, and then we look at the class of gro ...
Given a transitive permutation group, a fundamental object for studying its higher transitivity properties is the permutation action of its isotropy subgroup. We reverse this relationship and introduce a universal construction of infinite permutation group ...
Introduced 50 years ago by David Kazhdan, Kazhdan's Property (T) has quickly become an active research area in mathematics, with a lot of important results. A few years later, this property has been generalized to discrete group actions by Robert J. Zimmer ...
We study lattices in non-positively curved metric spaces. Borel density is established in that setting as well as a form of Mostow rigidity. A converse to the flat torus theorem is provided. Geometric arithmeticity results are obtained after a detour throu ...
Assume that we have a (compact) Riemann surface S, of genus greater than 2, with S = D/Gamma, where D is the complex unit disc and Gamma is a surface Fuchsian group. Let us further consider that S has an automorphism group G in such a way that the orbifold ...
The authors propose a numerical method for the uniformization of Riemann surfaces and algebraic curves in genus two with highly accurate results. Let G be a Fuchsian group acting on the unit disk BbbD, and let S=BbbD/G. It is well known that $S ...