Proper isometric actions of hyperbolic groups on -spaces
arXiv:1202.2597 · doi:10.1112/S0010437X12000693
Abstract
We show that every non-elementary hyperbolic group $\G$ admits a proper affine isometric action on $L^p(\bd\G\times \bd\G)$, where $\bd\G$ denotes the boundary of $\G$ and is large enough. Our construction involves a $\G$-invariant measure on $\bd\G\times \bd\G$ analogous to the Bowen - Margulis measure from the CAT setting, as well as a geometric cocycle à la Busemann. We also deduce that $\G$ admits a proper affine isometric action on the first -cohomology group $H^1_{(p)}(\G)$ for large enough .
17 pages