Property FW and 1-dimensional piecewise groups
Dynamical Systems
2021-05-11 v2 Group Theory
Abstract
Property FW is a natural combinatorial weakening of Kazhdan's Property T. We prove that the group of piecewise homographic self-transformations of the real projective line, has "few" infinite subgroups with Property FW. In particular, no such subgroup is amenable or has Kazhdan's Property T. These results are extracted from a longer paper. We provide a complete proof, whose main tools are the use of the notion of partial action and of one-dimensional geometric structures.
Cite
@article{arxiv.2003.11389,
title = {Property FW and 1-dimensional piecewise groups},
author = {Yves Cornulier},
journal= {arXiv preprint arXiv:2003.11389},
year = {2021}
}
Comments
10 pages. v2: expanded introduction