# Gauge freeness for Cuntz-Pimsner algebras

@article{Chirvasitu2018GaugeFF, title={Gauge freeness for Cuntz-Pimsner algebras}, author={A. Chirvasitu}, journal={arXiv: Operator Algebras}, year={2018} }

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.

#### 4 Citations

The graded structure of algebraic Cuntz-Pimsner rings

- Mathematics
- 2019

The algebraic Cuntz-Pimsner rings are naturally $\mathbb{Z}$-graded rings that generalize both Leavitt path algebras and unperforated $\mathbb{Z}$-graded Steinberg algebras. We classify strongly,… Expand

The graded structure of algebraic Cuntz-Pimsner rings

- Mathematics
- 2020

The algebraic Cuntz-Pimsner rings are naturally Z-graded rings that generalize both Leavitt path algebras and unperforated Z-graded Steinberg algebras. We classify strongly, epsilon-strongly and… Expand

Properties of the gradings on ultragraph algebras via the underlying combinatorics

- Mathematics
- 2021

There are two established gradings on Leavitt path algebras associated with ultragraphs, namely the grading by the integers group and the grading by the free group on the edges. In this paper, we… Expand

Strongly graded Leavitt path algebras

- Mathematics
- 2020

Let $R$ be a unital ring, let $E$ be a directed graph and recall that the Leavitt path algebra $L_R(E)$ carries a natural $\mathbb{Z}$-gradation. We show that $L_R(E)$ is strongly $\mathbb{Z}$-graded… Expand

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