We give lower bounds for the electrical resistance between vertices in the Schreier graphs of the action of the linear (degree 1) and quadratic (degree 2) mother groups on the orbit of the 0-ray. These bounds, combined with results of Juschenko et al. (2016), show that every quadratic activity automaton group is amenable. The resistance bounds use an apparently new “weighted” version of the Nash-Williams criterion which may be of independent interest.
@article{10_4171_ggd_821,
author = {Gideon Amir and Omer Angel and B\'alint Vir\'ag},
title = {Amenability of quadratic automaton groups},
journal = {Groups, geometry, and dynamics},
pages = {169--185},
year = {2025},
volume = {19},
number = {1},
doi = {10.4171/ggd/821},
url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/821/}
}
TY - JOUR
AU - Gideon Amir
AU - Omer Angel
AU - Bálint Virág
TI - Amenability of quadratic automaton groups
JO - Groups, geometry, and dynamics
PY - 2025
SP - 169
EP - 185
VL - 19
IS - 1
UR - http://geodesic.mathdoc.fr/articles/10.4171/ggd/821/
DO - 10.4171/ggd/821
ID - 10_4171_ggd_821
ER -
%0 Journal Article
%A Gideon Amir
%A Omer Angel
%A Bálint Virág
%T Amenability of quadratic automaton groups
%J Groups, geometry, and dynamics
%D 2025
%P 169-185
%V 19
%N 1
%U http://geodesic.mathdoc.fr/articles/10.4171/ggd/821/
%R 10.4171/ggd/821
%F 10_4171_ggd_821