Quasidiagonal Extensions and Sequentially Trivial Asymptotic Homomorphisms
نویسنده
چکیده
to be quasidiagonal when B⊗K contains an approximate unit of projections which is quasi-central in E, cf. [Sa]. He identified, under certain conditions, the subgroup of KK(A,B) which the quasidiagonal extensions correspond to under Kasparov’s isomorphism Ext(A,B) ' KK(A,B). C. Schochet has removed some of Salinas’ conditions in [S], the result being that when A is a unital C-algebra in the bootstrap category for which the UCT holds, and there exists a unital absorbing quasidiagonal extension of A by B ⊗ K, the subgroup of the Ext(A,B) corresponding to the quasidiagonal extensions can be identified with the group
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Quasidiagonal Morphisms and Homotopy
A linear operator acting on a separable Hilbert space is called quasidiagonal if it is a compact perturbation of a block-diagonal operator (see [H]). This notion extends to C*-algebras in the form of a local approximation property. Quasidiagonality has important applications to the extension theory of C*-algebras. It was shown by Voiculescu [V2] that quasidiagonality is a topological invariant....
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