English

Stable actions and central extensions

Dynamical Systems 2017-05-18 v2 Group Theory Operator Algebras

Abstract

A probability-measure-preserving action of a countable group is called stable if its transformation-groupoid absorbs the ergodic hyperfinite equivalence relation of type II_1 under direct product. We show that for a countable group G and its central subgroup C, if G/C has a stable action, then so does G. Combining a previous result of the author, we obtain a characterization of a central extension having a stable action.

Keywords

Cite

@article{arxiv.1604.04756,
  title  = {Stable actions and central extensions},
  author = {Yoshikata Kida},
  journal= {arXiv preprint arXiv:1604.04756},
  year   = {2017}
}

Comments

14 pages

R2 v1 2026-06-22T13:33:54.049Z