Extension of automorphisms to C*-crossed products with non-trivial centre
نویسندگان
چکیده
Given a quasi-special endomorphism ρ of a C∗ -algebra A with nontrivial center, we study an extension problem for automorphisms of A to a minimal cross-product B of A by ρ . Exploiting some aspects of the underlying generalized Doplicher-Roberts duality theory based on Pimsner algebras, an obstruction to the existence of such extensions is found and described in terms of sections of a suitable group bundle.
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تاریخ انتشار 2008