Groupoid algebras as covariance algebras
arXiv:1906.02855
Abstract
Suppose is a second-countable locally compact Hausdorff étale groupoid, is a discrete group containing a unital subsemigroup , and is a continuous cocycle. We derive conditions on the cocycle such that the reduced groupoid -algebra may be realised naturally as the covariance algebra of a product system over with coefficient algebra . When is a quasi-lattice ordered group, we also derive conditions that allow to be realised as the Cuntz--Nica--Pimsner algebra of a compactly aligned product system.
30 pages