Isometry groups of proper hyperbolic spaces
Group Theory
2008-03-16 v4 Geometric Topology
Abstract
Let X be a proper hyperbolic geodesic metric space and let G be a closed subgroup of the isometry group Iso(X) of X. We show that if G is not amenable then its second continuous bounded cohomology group with coefficients the regular representation does not vanish. This yields some structure results for such groups.
Cite
@article{arxiv.math/0507608,
title = {Isometry groups of proper hyperbolic spaces},
author = {Ursula Hamenstadt},
journal= {arXiv preprint arXiv:math/0507608},
year = {2008}
}
Comments
30 pages; writing improved, details added. Combined with parts of math.GR/0508532. To appear in GAFA