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arXiv · 2604.27446

A class of Exel--Laca algebras reciprocal to Cuntz--Krieger algebras

Kengo Matsumoto·Taro Sogabe
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Abstract

The reciprocality means a duality in Kirchberg algebras between K-theory groups and strong extension groups. In the paper, we will find a certain class of unital simple Exel--Laca algebras for which the reciprocal duals are simple Cuntz--Krieger algebras in terms of the underlying infinite matrices. In our procedure to obtain simple Cuntz--Krieger algebras from Exel--Laca algebras, we compute the strong extension groups for Exel--Laca algebras belonging to the class.

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Kengo Matsumoto, Taro Sogabe. 2026-04-30. A class of Exel--Laca algebras reciprocal to Cuntz--Krieger algebras. https://arxiv.org/abs/2604.27446

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