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Group bundle duality, invariants for certain C*-algebras, and twisted equivariant K-theory

Ezio Vasselli
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Abstract

A duality is discussed for Lie group bundles vs. certain tensor categories with non-simple identity, in the setting of Nistor-Troitsky gauge-equivariant K-theory. As an application, we study C*-algebra bundles with fibre a fixed-point algebra of the Cuntz algebra: a classification is given, and a cohomological invariant is assigned, representing the obstruction to perform an embedding into a continuous bundle of Cuntz algebras. Finally, we introduce the notion of twisted equivariant K-theory.

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Ezio Vasselli. 2007-12-03. Group bundle duality, invariants for certain C*-algebras, and twisted equivariant K-theory. https://arxiv.org/abs/math/0605114

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