Weakly proper group actions, Mansfield’s Imprimitivity and twisted Landstad duality

Buss, Alcides; Echterhoff, Siegfried

doi:10.1090/S0002-9947-2015-06406-X

Weakly proper group actions, Mansfield’s Imprimitivity and twisted Landstad duality
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by Alcides Buss and Siegfried Echterhoff PDF

Trans. Amer. Math. Soc. 368 (2016), 249-280 Request permission

Abstract:

Using the theory of weakly proper actions of locally compact groups recently developed by the authors, we give a unified proof of both reduced and maximal versions of Mansfield’s Imprimitivity Theorem and obtain a general version of Landstad’s Duality Theorem for twisted group coactions. As one application, we obtain the stabilization trick for arbitrary twisted coactions, showing that every twisted coaction is Morita equivalent to an inflated coaction.

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