English

Ozawa's class $\mathcal S$ for locally compact groups and unique prime factorization

Operator Algebras 2019-04-29 v2 Dynamical Systems Group Theory

Abstract

We study class S\mathcal S for locally compact groups. We characterize locally compact groups in this class as groups having an amenable action on a boundary that is small at infinity, generalizing a theorem of Ozawa. Using this characterization, we provide new examples of groups in class S\mathcal S and prove unique prime factorization results for group von Neumann algebras of products of locally compact groups in this class. We also prove that class S\mathcal S is a measure equivalence invariant.

Keywords

Cite

@article{arxiv.1904.02090,
  title  = {Ozawa's class $\mathcal S$ for locally compact groups and unique prime factorization},
  author = {Tobe Deprez},
  journal= {arXiv preprint arXiv:1904.02090},
  year   = {2019}
}

Comments

v2: changed references to and comments on examples at the end of introduction; more general version of Proposition 4.4

R2 v1 2026-06-23T08:28:20.901Z