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arXiv · 0911.0539

Coactions of Hopf C*-bimodules

Thomas Timmermann
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Abstract

Coactions of Hopf C*-bimodules simultaneously generalize coactions of Hopf C*-algebras and actions of groupoids. Following an approach of Baaj and Skandalis, we construct reduced crossed products and establish a duality for fine coactions. Examples of coactions arise from Fell bundles on groupoids and actions of a groupoid on bundles of C*-algebras. Continuous Fell bundles on an etale groupoid correspond to coactions of the reduced groupoid algebra, and actions of a groupoid on a continuous bundle of C*-algebras correspond to coactions of the function algebra.

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Thomas Timmermann. 2009-11-03. Coactions of Hopf C*-bimodules. https://arxiv.org/abs/0911.0539

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