English

Relative C*-simplicity and characterizations for normal subgroups

Operator Algebras 2022-10-21 v3 Group Theory

Abstract

The notion of a plump subgroup was recently introduced by Amrutam. This is a relativized version of Powers' averaging property, and it is known that Powers' averaging property is equivalent to C*-simplicity. With this in mind, we introduce a relativized notion of C*-simplicity, and show that for normal subgroups it is equivalent to plumpness, along with several other characterizations.

Cite

@article{arxiv.1910.13495,
  title  = {Relative C*-simplicity and characterizations for normal subgroups},
  author = {Dan Ursu},
  journal= {arXiv preprint arXiv:1910.13495},
  year   = {2022}
}

Comments

15 pages; To appear in the Journal of Operator Theory. This is the accepted manuscript, which includes minor corrections made during the refereeing process. Author funding information was also corrected

R2 v1 2026-06-23T11:58:49.080Z