English

A groupoid approach to L\"uck's amenability conjecture

Group Theory 2013-05-16 v2 K-Theory and Homology

Abstract

We prove that amenability of a discrete group is equivalent to dimension flatness of certain ring inclusions naturally associated with measure preserving actions of the group. This provides a group-measure space theoretic solution to a conjecture of L\"uck stating that amenability of a group is characterized by dimension flatness of the inclusion of its complex group algebra into the associated von Neumann algebra.

Keywords

Cite

@article{arxiv.1205.1930,
  title  = {A groupoid approach to L\"uck's amenability conjecture},
  author = {David Kyed and Henrik Densing Petersen},
  journal= {arXiv preprint arXiv:1205.1930},
  year   = {2013}
}

Comments

30 pages; to appear in Osaka Journal of Mathematics

R2 v1 2026-06-21T21:00:42.406Z