Fundamental group of simple $C^*$-algebras with unique trace

Norio Nawata; Yasuo Watatani

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arXiv · 0904.1081

Fundamental group of simple $C^*$-algebras with unique trace

Norio Nawata·Yasuo Watatani

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Abstract

We introduce the fundamental group ${\mathcal F}(A)$ of a unital simple $C^*$-algebra $A$ with a unique normalized trace. We compute fundamental groups ${\mathcal F}(A)$ of several nuclear or non-nuclear $C^*$-algebras $A$. K-theoretical obstruction enables us to compute the fundamental group easily. Our study is essentially based on the computation of Picard groups by Kodaka.

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Norio Nawata, Yasuo Watatani. 2009-04-07. Fundamental group of simple $C^*$-algebras with unique trace. https://arxiv.org/abs/0904.1081

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