English

Exotic groupoid $C^*$-algebras associated to double groupoids

Operator Algebras 2024-09-06 v5

Abstract

We consider a class of partial action groupoids called double groupoids which are constructed from pairs of subgroups satisfying similar conditions to those of a matched pair of groups. If the double groupoid is \'etale, then we show that whenever the partially acting group admit exotic ideal completions in the sense of Brown and Guentner, the corresponding double groupoid also admit exotic CC^*-completions.

Keywords

Cite

@article{arxiv.2404.11297,
  title  = {Exotic groupoid $C^*$-algebras associated to double groupoids},
  author = {Mathias Palmstrøm},
  journal= {arXiv preprint arXiv:2404.11297},
  year   = {2024}
}

Comments

17 pages; to appear in Math. Scand.; strengthened Example 4.1 by suggestion of the anonymous referee, fixed some typos and updated the bibliography

R2 v1 2026-06-28T15:57:08.482Z