Co-spectral radius of intersections
Group Theory
2023-02-13 v2
Abstract
We study the behavior of the co-spectral radius of a subgroup of a discrete group under taking intersections. Our main result is that the co-spectral radius of an invariant random subgroup does not drop upon intersecting with a deterministic co-amenable subgroup. As an application, we find that the intersection of independent co-amenable invariant random subgroups is co-amenable.
Cite
@article{arxiv.2206.14251,
title = {Co-spectral radius of intersections},
author = {Mikolaj Fraczyk and Wouter van Limbeek},
journal= {arXiv preprint arXiv:2206.14251},
year = {2023}
}
Comments
Minor changes following referee's comments. 15 p, comments welcome!