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Gauge Invariant Uniqueness Theorem for Corners of k-graphs

Stephen Allen
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Abstract

For a finitely aligned k-graph $Λ$ with X a set of vertices in $Λ$ we define a universal C*-algebra called $C^*(Λ,X)$ generated by partial isometries. We show that $C^*(Λ,X)$ is isomorphic to the corner $P_XC^*(Λ)P_X$, where $P_X$ is the sum of vertex projections in X. We then prove a version of the Gauge Invariant Uniqueness Theorem for $C^*(Λ,X)$, and then use the theorem to prove various results involving fullness, simplicity and Morita equivalence as well as new results involving symbolic dynamics.

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Stephen Allen. 2005-06-29. Gauge Invariant Uniqueness Theorem for Corners of k-graphs. https://arxiv.org/abs/math/0506582

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