Inverted orbits of exclusion processes, diffuse-extensive-amenability and (non-?)amenability of the interval exchanges
Abstract
The recent breakthrough works [6,8,9] which established the amenability for new classes of groups, lead to the following question: is the action extensively amenable? (Where is the {\em wobbling group} of permutations with bounded range). This is equivalent to asking whether the action is amenable. The and and have been settled respectively in [6,8]. By [9], a positive answer to this question would imply the amenability of the IET group. In this work, we give a partial answer to this question by introducing a natural strengthening of the notion of extensive-amenability which we call diffuse-extensive-amenability. Our main result is that for any bounded degree graph , the action is diffuse-extensively amenable if and only if is recurrent. Our proof is based on the construction of suitable stochastic processes on whose {\em inverted orbits} are exponentially unlikely to be sub-linear when is transient. This result leads us to conjecture that the action is not extensively amenable when and that a different route towards the (non-?)amenability of the IET group may be needed.
Keywords
Cite
@article{arxiv.1804.01981,
title = {Inverted orbits of exclusion processes, diffuse-extensive-amenability and (non-?)amenability of the interval exchanges},
author = {Christophe Garban},
journal= {arXiv preprint arXiv:1804.01981},
year = {2020}
}
Comments
23 pages (minor changes)