Decomposition of Borel graphs and cohomology
Group Theory
2026-03-12 v3 Dynamical Systems
Logic
Abstract
We give a cohomological criterion for certain decomposition of Borel graphs, which is an analog of Dunwoody's work on accessibility of groups. As an application, we prove that a Borel graph with uniformly bounded degrees of cohomological dimension one is Lipschitz equivalent to a Borel acyclic graph on . This gives a new proof of a result of Chen-Poulin-Tao-Tserunyan on Borel graphs with components quasi-isometric to trees.
Cite
@article{arxiv.2504.17831,
title = {Decomposition of Borel graphs and cohomology},
author = {Hiroki Ishikura},
journal= {arXiv preprint arXiv:2504.17831},
year = {2026}
}
Comments
Introduction is updated