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arXiv · 2208.08001

On strong extension groups of Cuntz--Krieger algebras

Kengo Matsumoto
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Abstract

In this paper, we study the strong extension groups of Cuntz--Krieger algebras, and present a formula to compute the groups. We also detect the position of the Toeplitz extension of a Cuntz--Krieger algebra in the strong extension group and in the weak extension group to see that the weak extension group with the position of the Toeplitz extension is a complete invariant of the isomorphism class of the Cuntz--Krieger algebra associated with its transposed matrix.

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Kengo Matsumoto. 2022-08-17. On strong extension groups of Cuntz--Krieger algebras. https://arxiv.org/abs/2208.08001

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