English

A note on asynchronously automatic groups and notions of non-positive curvature

Group Theory 2025-08-01 v2

Abstract

We prove groups acting cocompactly on locally finite trees with hyperbolic vertex stabilisers are asynchronously automatic. Combining this with previous work of the authors, we obtain an example of a group satisfying several non-positive curvature properties (being a CAT(0)\mathrm{CAT}(0) group, an injective group, a hierarchically hyperbolic group, and having quadratic Dehn function) which is asynchronously automatic but not biautomatic.

Keywords

Cite

@article{arxiv.2304.01832,
  title  = {A note on asynchronously automatic groups and notions of non-positive curvature},
  author = {Sam Hughes and Motiejus Valiunas},
  journal= {arXiv preprint arXiv:2304.01832},
  year   = {2025}
}

Comments

v2: 11 pages, 2 figures, minor changes, to appear in Algebraic & Geometric Topology; v1: 10 pages, 2 figures, comments welcome!