Classification of inductive limits of 1-dimensional NCCW complexes

Leonel Robert

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arXiv · 1007.1964

Classification of inductive limits of 1-dimensional NCCW complexes

Leonel Robert

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Abstract

A classification result is obtained for the C*-algebras that are (stably isomorphic to) inductive limits of 1-dimensional noncommutative CW complexes with trivial $K_1$-group. The classifying functor Cu is defined in terms of the Cuntz semigroup of the unitization of the algebra. For the simple C*-algebras covered by the classification, Cu reduces to the ordered $K_0$-group, the cone of traces, and the pairing between them. As an application of the classification, it is shown that the crossed products by a quasi-free action $O_2\rtimes_\lambda \mathbb{R}$ are all isomorphic for a dense set of positive irrational numbers $\lambda$.

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Leonel Robert. 2010-07-12. Classification of inductive limits of 1-dimensional NCCW complexes. https://arxiv.org/abs/1007.1964

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