• Corpus ID: 13793213

# Isometry groups of proper hyperbolic spaces

@inproceedings{Hamenstdt2005IsometryGO,
title={Isometry groups of proper hyperbolic spaces},
author={Ursula Hamenstādt},
year={2005}
}
Let X be a proper hyperbolic geodesic metric space of bounded growth and let G be a closed subgroup of the isometry group Iso(X) of X. We show that if G is not amenable then the second continuous bounded cohomol-ogy group H 2 cb (G, L 2 (G)) does not vanish. As an application, we derive some structure results for closed subgroups of Iso(X).
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