Proper actions on finite products of quasi-trees
arXiv:1905.10813
Abstract
We say that a finitely generated group has property (QT) if it acts isometrically on a finite product of quasi-trees so that orbit maps are quasi-isometric embeddings. A quasi-tree is a connected graph with path metric quasi-isometric to a tree, and product spaces are equipped with the -metric. As an application of the projection complex techniques, we prove that residually finite hyperbolic groups and mapping class groups have (QT).
Minor changes with a few references added. Accepted by Annales Henri Lebesgue