# Opposite algebras of groupoid C*-algebras

@article{Buss2017OppositeAO, title={Opposite algebras of groupoid C*-algebras}, author={Alcides Buss and Aidan Sims}, journal={Israel Journal of Mathematics}, year={2017}, volume={244}, pages={759 - 774} }

We show that every groupoid C*-algebra is isomorphic to its opposite, and deduce that there exist C*-algebras that are not stably isomorphic to groupoid C*-algebras, though many of them are stably isomorphic to twisted groupoid C*-algebras. We also prove that the opposite algebra of a section algebra of a Fell bundle over a groupoid is isomorphic to the section algebra of a natural opposite bundle.

## One Citation

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