Groupoid algebras as Cuntz-Pimsner algebras


  • Adam Rennie
  • David Robertson
  • Aidan Sims



We show that if $G$ is a second countable locally compact Hausdorff étale groupoid carrying a suitable cocycle $c\colon G\to\mathbb{Z}$, then the reduced $C^*$-algebra of $G$ can be realised naturally as the Cuntz-Pimsner algebra of a correspondence over the reduced $C^*$-algebra of the kernel $G_0$ of $c$. If the full and reduced $C^*$-algebras of $G_0$ coincide, we deduce that the full and reduced $C^*$-algebras of $G$ coincide. We obtain a six-term exact sequence describing the $K$-theory of $C^*_r(G)$ in terms of that of $C^*_r(G_0)$.


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How to Cite

Rennie, A., Robertson, D., & Sims, A. (2017). Groupoid algebras as Cuntz-Pimsner algebras. MATHEMATICA SCANDINAVICA, 120(1), 115–123.