English

Groupoid C*-algebras with Hausdorff Spectrum

Operator Algebras 2012-07-31 v1

Abstract

Suppose GG is a second countable, locally compact Hausdorff groupoid with abelian stabilizer subgroups and a Haar system. We provide necessary and sufficient conditions for the groupoid CC^*-algebra to have Hausdorff spectrum. In particular we show that the spectrum of C(G)C^*(G) is Hausdorff if and only if the stabilizers vary continuously with respect to the Fell topology, the orbit space G(0)/GG^{(0)}/G is Hausdorff, and, given convergent sequences χiχ\chi_i\to \chi and γiχiω\gamma_i\cdot\chi_i \to \omega in the dual stabilizer groupoid S^\hat{S} where the γiG\gamma_i\in G act via conjugation, if χ\chi and ω\omega are elements of the same fiber then χ=ω\chi = \omega

Keywords

Cite

@article{arxiv.1207.6715,
  title  = {Groupoid C*-algebras with Hausdorff Spectrum},
  author = {Geoff Goehle},
  journal= {arXiv preprint arXiv:1207.6715},
  year   = {2012}
}

Comments

10 pages

R2 v1 2026-06-21T21:42:57.481Z