Simplicity of C-algebras Associated to Higher-rank Graphs
نویسنده
چکیده
We prove that if Λ is a row-finite k-graph with no sources, then the associated C∗-algebra is simple if and only if Λ is cofinal and satisfies Kumjian and Pask’s Condition (A). We prove that Condition (A) is equivalent to a suitably modified version of Robertson and Steger’s original nonperiodicity condition (H3) which in particular involves only finite paths. We also characterise both cofinality and aperiodicity of Λ in terms of ideals in C∗(Λ).
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تاریخ انتشار 2008