English

Symmetries of the C*-algebra of a vector bundle

Operator Algebras 2019-12-05 v1

Abstract

We consider CC^*-algebras constructed from compact group actions on complex vector bundles EXE\to X endowed with a Hermitian metric. An action of GG by isometries on EXE\to X induces an action on the CC^*-correspondence Γ(E)\Gamma(E) over C(X)C(X) consisting of continuous sections, and on the associated Cuntz-Pimsner algebra OE\mathcal O_E, so we can study the crossed product OEG\mathcal O_E\rtimes G. If the action is free and rank E=nE=n, then we prove that OEG\mathcal O_E\rtimes G is Morita-Rieffel equivalent to a field of Cuntz algebras On\mathcal O_n over the orbit space X/GX/G. If the action is fiberwise, then OEG\mathcal O_E\rtimes G becomes a continuous field of crossed products OnG\mathcal O_n\rtimes G. For transitive actions, we show that OEG\mathcal O_E\rtimes G is Morita-Rieffel equivalent to a graph CC^*-algebra.

Keywords

Cite

@article{arxiv.1912.01750,
  title  = {Symmetries of the C*-algebra of a vector bundle},
  author = {Valentin Deaconu},
  journal= {arXiv preprint arXiv:1912.01750},
  year   = {2019}
}