Automorphisms of contact graphs of ${\rm CAT(0)}$ cube complexes
Abstract
We show that, under weak assumptions, the automorphism group of a cube complex coincides with the automorphism group of Hagen's contact graph . The result holds, in particular, for universal covers of Salvetti complexes, where it provides an analogue of Ivanov's theorem on curve graphs of non-sporadic surfaces. This highlights a contrast between contact graphs and Kim-Koberda extension graphs, which have much larger automorphism group. We also study contact graphs associated to Davis complexes of right-angled Coxeter groups. We show that these contact graphs are less well-behaved and describe exactly when they have more automorphisms than the universal cover of the Davis complex.
Keywords
Cite
@article{arxiv.2001.08493,
title = {Automorphisms of contact graphs of ${\rm CAT(0)}$ cube complexes},
author = {Elia Fioravanti},
journal= {arXiv preprint arXiv:2001.08493},
year = {2026}
}
Comments
16 pages, no figures; v2: published version, open access on IMRN