# 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

- Mathematics
- 2005

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

- Mathematics
- 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…

Geometry of the mapping class groups I: Boundary amenability

- Mathematics
- 2005

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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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…

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