Corpus ID: 102353793

Gauge freeness for Cuntz-Pimsner algebras

  title={Gauge freeness for Cuntz-Pimsner algebras},
  author={Alexandru Chirvasitu},
  journal={arXiv: Operator Algebras},
To every $C^*$ correspondence over a $C^*$-algebra one can associate a Cuntz-Pimsner algebra generalizing crossed product constructions, graph $C^*$-algebras, and a host of other classes of operator algebras. Cuntz-Pimsner algebras come equipped with a `gauge action' by the circle group and its finite subgroups. For unital Cuntz-Pimsner algebras, we derive necessary and sufficient conditions for the gauge actions (by either the circle or its closed subgroups) to be free. 
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