# Twisted k-Graph Algebras Associated to Bratteli Diagrams

@article{Pask2014TwistedKA, title={Twisted k-Graph Algebras Associated to Bratteli Diagrams}, author={David Pask and Adam Sierakowski and Aidan Sims}, journal={Integral Equations and Operator Theory}, year={2014}, volume={81}, pages={375-408} }

Given a system of coverings of k-graphs, we show that the second cohomology of the resulting (k + 1)-graph is isomorphic to that of any one of the k-graphs in the system, and compute the semifinite traces of the resulting twisted (k + 1)-graph C*-algebras. We then consider Bratteli diagrams of 2-graphs whose twisted C*-algebras are matrix algebras over noncommutative tori. For such systems we calculate the ordered K-theory of the resulting twisted 3-graph C*-algebras. We deduce that every such…

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