# Simplicity of twisted C*-algebras of Deaconu--Renault groupoids

@inproceedings{Armstrong2021SimplicityOT, title={Simplicity of twisted C*-algebras of Deaconu--Renault groupoids}, author={Becky Armstrong and Nathan Brownlowe and Aidan Sims}, year={2021} }

We consider Deaconu–Renault groupoids associated to actions of finite-rank free abelian monoids by local homeomorphisms of locally compact Hausdorff spaces. We study simplicity of the twisted C*-algebra of such a groupoid determined by a continuous circle-valued groupoid 2-cocycle. When the groupoid is not minimal, this C*-algebra is never simple, so we focus on minimal groupoids. We describe an action of the quotient of the groupoid by the interior of its isotropy on the spectrum of the… Expand

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