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arXiv · 1508.07605

Fundamental group of $C^{*}$-algebras with finite dimensional trace space

Takashi Kawahara
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Abstract

We introduce the fundamental group $rF(cA)$ of a unital $C^*$-algebra $cA$ with finite dimensional trace space. The elements of fundamental group are restricted by K-theoretical obstruction and positivity. Moreover we show there are uncountably many mutually nonisomorphic simple $C^{*}$-algebras such that $rF(cA)=\set{I_{n}}$. Our study is due to the results of fundamental group by Nawata and Watatani.

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Takashi Kawahara. 2016-02-10. Fundamental group of $C^{*}$-algebras with finite dimensional trace space. https://arxiv.org/abs/1508.07605

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