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arXiv · 1311.4638

Factoriality and type classification of \textsf{k}-graph von Neumann algebras

Dilian Yang
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Abstract

Let $\Fth$ be a single vertex \textsf{k}-graph, and $\pi_\omega(\O_\theta)"$ be the von Neumann algebra induced from the GNS representation of a distinguished state $\omega$ of its $\textsf{k}$-graph C*-algebra $\O_\theta$. In this paper, we prove the factoriality of $\pi_\omega(\O_\theta)"$ and further determine its type, when either $\Fth$ has the little pull-back property, or the intrinsic group of $\Fth$ has rank $0$. The key step to achieve this is to show that the fixed point algebra of the modular action corresponding to $\omega$ has a unique tracial state.

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Dilian Yang. 2013-11-19. Factoriality and type classification of \textsf{k}-graph von Neumann algebras. https://arxiv.org/abs/1311.4638

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