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Crossed products by endomorphisms, vector bundles and group duality, II

Ezio Vasselli
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Abstract

We study C*-algebra endomorphims which are special in a weaker sense w.r.t. the notion introduced by Doplicher and Roberts. We assign to such endomorphisms a geometrical invariant, representing a cohomological obstruction for them to be special in the usual sense. Moreover, we construct the crossed product of a C*-algebra by the action of the dual of a (nonabelian, noncompact) group of vector bundle automorphisms. These crossed products supply a class of examples for such generalized special endomorphisms.

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Ezio Vasselli. 2004-12-31. Crossed products by endomorphisms, vector bundles and group duality, II. https://doi.org/10.1142/s0129167x06003321

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