The Dixmier-Douady class of groupoid crossed products
نویسندگان
چکیده
منابع مشابه
Principal Bundles and the Dixmier Douady Class
A systematic consideration of the problem of the reduction and extension of the structure group of a principal bundle is made and a variety of techniques in each case are explored and related to one another. We apply these to the study of the DixmierDouady class in various contexts including string structures, Ures bundles and other examples motivated by considerations from quantum field theory.
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Let G → B be a bundle of compact Lie groups acting on a fiber bundle Y → B. In this paper we introduce and study gauge-equivariant K-theory groups K G(Y ). These groups satisfy the usual properties of the equivariant K-theory groups, but also some new phenomena arise due to the topological non-triviality of the bundle G → B. As an application, we define a gauge-equivariant index for a family of...
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ژورنال
عنوان ژورنال: Journal of the Australian Mathematical Society
سال: 2004
ISSN: 1446-7887,1446-8107
DOI: 10.1017/s1446788700008910