Extension groups for the $C^*$-algebras associated with $\lambda$-graph systems

Kengo Matsumoto

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arXiv · 2405.03204

Extension groups for the $C^*$-algebras associated with $\lambda$-graph systems

Kengo Matsumoto

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Abstract

A $\lambda$-graph system is a labeled Bratteli diagram with certain additional structure, which presents a subshift. The class of the $C^*$-algebras $\mathcal{O}_{\frak L}$ associated with the $\lambda$-graph systems is a generalized class of the class of Cuntz--Krieger algebras. In this paper, we will compute the strong extension groups $\operatorname{Ext}_{\operatorname{s}}(\mathcal{O}_{\frak L})$ for the $C^*$-algebras associated with $\lambda$-graph systems ${\frak L}$ and study their relation with the weak extension group $\operatorname{Ext}_{\operatorname{w}}(\mathcal{O}_{\frak L})$.

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BibTeX RIS

Kengo Matsumoto. 2024-05-06. Extension groups for the $C^*$-algebras associated with $\lambda$-graph systems. https://arxiv.org/abs/2405.03204

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