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تسجيل مستخدم جديدC*-envelopes and the Hao-Ng isomorphism for discrete groups
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تأليف
Elias G. Katsoulis
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Using non-selfadjoint techniques, we establish the Hao-Ng isomorphism for the reduced crossed product and all discrete groups. For the full crossed product an analogous result holds for all discrete groups but the C*-correspondences involved have to be hyperrigid. These results are obtained by calculating the C*-envelope of the reduced crossed product of an operator algebra by a discrete group.
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In an earlier work, the authors proposed a non-selfadjoint approach to the Hao-Ng isomorphism problem for the full crossed product, depending on the validity of two conjectures stated in the broader context of crossed products for operator algebras.
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Let $A$ be a unital operator algebra and let $alpha$ be an automorphism of $A$ that extends to a *-automorphism of its $ca$-envelope $cenv (A)$. In this paper we introduce the isometric semicrossed product $A times_{alpha}^{is} bbZ^+ $ and we show th
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This paper is an expanded version of the lectures I delivered at the Indian Statistical Institute, Bangalore, during the OTOA 2014 conference.
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