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arXiv · 0710.5800

Cuntz semigroups of ideals and quotients and a generalized Kasparov Stabilization Theorem

Alin Ciuperca·Leonel Robert·Luis Santiago
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Abstract

Let A be a C*-algebra and I a closed two-sided ideal of A. We use the Hilbert C*-modules picture of the Cuntz semigroup to investigate the relations between the Cuntz semigroups of I, A and A/I. We obtain a relation on two elements of the Cuntz semigroup of A that characterizes when they are equal in the Cuntz semigroup of A/I. As a corollary, we show that the Cuntz semigroup functor is exact. Replacing the Cuntz equivalence relation of Hilbert modules by their isomorphism, we obtain a generalization of Kasparov's Stabilization theorem.

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Alin Ciuperca, Leonel Robert, Luis Santiago. 2007-10-31. Cuntz semigroups of ideals and quotients and a generalized Kasparov Stabilization Theorem. https://arxiv.org/abs/0710.5800

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