Cartan semigroups and twisted groupoid C*-algebras
Operator Algebras
2025-04-25 v2
Abstract
We prove that twisted groupoid C*-algebras are characterised, up to isomorphism, by having Cartan semigroups, a natural generalisation of normaliser semigroups of Cartan subalgebras. This extends the classic Kumjian-Renault theory to general twisted \'etale groupoid C*-algebras, even non-reduced C*-algebras of non-effective groupoids.
Keywords
Cite
@article{arxiv.2407.05024,
title = {Cartan semigroups and twisted groupoid C*-algebras},
author = {Tristan Bice and Lisa Orloff Clark and Ying-Fen Lin and Kathryn McCormick},
journal= {arXiv preprint arXiv:2407.05024},
year = {2025}
}
Comments
40 pages, accepted version by JFA