• Corpus ID: 18105882

# Bounded cohomology, cross ratios and cocycles

@article{Hamenstaedt2005BoundedCC,
title={Bounded cohomology, cross ratios and cocycles},
author={Ursula Hamenstaedt},
journal={arXiv: Group Theory},
year={2005}
}
We use cross ratios to describe second real continuous bounded cohomology for locally compact topological groups. We also derive a rigidity result for cocycles with values in the isometry group of a proper hyperbolic geodesic metric space.
3 Citations
Isometry Groups of Proper Hyperbolic Spaces
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 elementary then for every p ∈ (1, ∞) the second
Isometry groups of proper hyperbolic spaces
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
Geometry of the mapping class groups I: Boundary amenability
We construct a geometric model for the mapping class group $\mathcal{M}\mathcal{C}\mathcal{G}$ of a non-exceptional oriented surface S of genus g with k punctures and use it to show that the action

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