m at h . O A ] 3 J an 2 00 4 COVERINGS OF k - GRAPHS
نویسنده
چکیده
k-graphs are higher-rank analogues of directed graphs which were first developed to provide combinatorial models for operator algebras of Cuntz-Krieger type. Here we develop the theory of covering spaces for k-graphs, obtaining a satisfactory version of the usual topological classification in terms of subgroups of a fundamental group. We then use this classification to describe the C∗algebras of covering k-graphs as crossed products by coactions of homogeneous spaces, generalizing recent results on the C∗-algebras of graphs.
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