Skew-products of higher-rank graphs and crossed products by semigroups
نویسندگان
چکیده
We consider a free action of an Ore semigroup on a higher-rank graph, and the induced action by endomorphisms of the C ∗-algebra of the graph. We show that the crossed product by this action is stably isomorphic to the C ∗-algebra of a quotient graph. Our main tool is Laca’s dilation theory for endomorphic actions of Ore semigroups on C ∗-algebras, which embeds such an action in an automorphic action of the enveloping group on a larger C ∗-algebra.
منابع مشابه
Coverings of skew products and crossed products by coactions
Consider a projective limit G of finite groups Gn. Fix a compatible family δn of coactions of the Gn on a C ∗-algebra A. From this data we obtain a coaction δ of G on A. We show that the coaction crossed product of A by δ is isomorphic to a direct limit of the coaction crossed products of A by the δn. If A = C∗(Λ) for some k-graph Λ, and if the coactions δn correspond to skewproducts of Λ, then...
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