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arXiv · 2103.02816

C*-dynamical invariants and Toeplitz algebras of graphs

Chris Bruce·Takuya Takeishi
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Abstract

In recent joint work of the authors with Laca, we precisely formulated the notion of partition function in the context of C*-dynamical systems. Here, we compute the partition functions of C*-dynamical systems arising from Toeplitz algebras of graphs, and we explicitly recover graph-theoretic information in terms of C*-dynamical invariants. In addition, we compute the type for KMS states on C*-algebras of finite (reducible) graphs and prove that the extremal KMS states at critical inverse temperatures give rise to type III$_\lambda$ factors. Our starting point is an independent result parameterising the partition functions of a certain class of C*-dynamical systems arising from groupoid C*-algebras in terms of $\beta$-summable orbits.

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Chris Bruce, Takuya Takeishi. 2021-03-04. C*-dynamical invariants and Toeplitz algebras of graphs. https://arxiv.org/abs/2103.02816

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