Orbit equivalence of graphs and isomorphism of graph groupoids
Abstract
We show that the groupoids of two directed graphs are isomorphic if and only if the two graphs are orbit equivalent by an orbit equivalence that preserves isolated eventually periodic points. We also give a complete description of the (topological) isolated points of the boundary path space of a graph. As a result, we are able to show that the groupoids of two directed graphs with finitely many vertices and no sinks are isomorphic if and only if the two graphs are orbit equivalent, and that the groupoids of the stabilisations of two such graphs are isomorphic if and only if the stabilisations of the graphs are orbit equivalent.
Keywords
Cite
@article{arxiv.1610.09942,
title = {Orbit equivalence of graphs and isomorphism of graph groupoids},
author = {Toke Meier Carlsen and Marius Lie Winger},
journal= {arXiv preprint arXiv:1610.09942},
year = {2018}
}
Comments
9 pages. In version 3 the list of references has been updated and some misprints have been corrected. This is the version that will be published