Deforming cubulations of hyperbolic groups
Abstract
We describe a procedure to deform cubulations of hyperbolic groups by "bending hyperplanes". Our construction is inspired by related constructions like Thurston's Mickey Mouse example, walls in fibred hyperbolic -manifolds and free-by- groups, and Hsu-Wise turns. As an application, we show that every cocompactly cubulated Gromov-hyperbolic group admits a proper, cocompact, essential action on a cube complex with a single orbit of hyperplanes. This answers (in the negative) a question of Wise, who proved the result in the case of free groups. We also study those cubulations of a general group that are not susceptible to trivial deformations. We name these "bald cubulations" and observe that every cocompactly cubulated group admits at least one bald cubulation. We then apply the hyperplane-bending construction to prove that every cocompactly cubulated hyperbolic group admits infinitely many bald cubulations, provided is not a virtually free group with finite. By contrast, we show that the Burger-Mozes examples each admit a unique bald cubulation.
Cite
@article{arxiv.1912.10999,
title = {Deforming cubulations of hyperbolic groups},
author = {Elia Fioravanti and Mark Hagen},
journal= {arXiv preprint arXiv:1912.10999},
year = {2026}
}
Comments
44 pages, 4 figures; to appear on Journal of Topology