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arXiv · 2606.20181

On the relation between the product of KK-groups and the KK-group of the product

Diego Martínez
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Abstract

We observe that the canonical map \(KK(A, \prod_{n \in \mathbb{N}} B_n) \to \prod_{n \in \mathbb{N}} KK(A,B_n)\) is an isomorphism of abelian groups whenever \(A\) enjoys the Universal Coefficient Theorem and \(B_n\) are unital, simple and purely infinite C*-algebras. This clarifies an aspect of previous work of Dadarlat--Eilers and Tikuisis--White--Winter.

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Diego Martínez. 2026-06-18. On the relation between the product of KK-groups and the KK-group of the product. https://arxiv.org/abs/2606.20181

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