Imprimitivity for C-coactions of Non-amenable Groups
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چکیده
We give a condition on a full coaction (A,G, δ) of a (possibly) nonamenable group G and a closed normal subgroup N of G which ensures that Mansfield imprimitivity works; i.e. that A×δ| G/N is Morita equivalent to A×δ G×δ̂,r N . This condition obtains if N is amenable or δ is normal. It is preserved under Morita equivalence, inflation of coactions, the stabilization trick of Echterhoff and Raeburn, and on passing to twisted coactions.
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تاریخ انتشار 1996