The Cuntz semigroup of continuous fields

Ramon Antoine; Joan Bosa; Francesc Perera

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arXiv · 1205.6608

The Cuntz semigroup of continuous fields

Ramon Antoine·Joan Bosa·Francesc Perera

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Abstract

In this paper we describe the Cuntz semigroup of continuous fields of C$^*$-algebras over one dimensional spaces whose fibers have stable rank one and trivial $K_1$ for each closed, two-sided ideal. This is done in terms of the semigroup of global sections on a certain topological space built out of the Cuntz semigroups of the fibers of the continuous field. When the fibers have furthermore real rank zero, and taking into account the action of the space, our description yields that the Cuntz semigroup is a classifying invariant if and only if so is the sheaf induced by the Murray-von Neumann semigroup.

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Ramon Antoine, Joan Bosa, Francesc Perera. 2012-05-30. The Cuntz semigroup of continuous fields. https://arxiv.org/abs/1205.6608

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