Asymptotic Unitary Equivalence in KK-Theory
نویسندگان
چکیده
A description of the Kasparov group KK(A,B) is given in terms of Cuntz pairs of representations and the notion of proper asymptotic unitary equivalence that we introduce here. The use of the word ‘proper’ reflects the crucial fact that all unitaries implementing the equivalence can be chosen to be compact perturbations of identity. The result has significant applications to the classification theory of nuclear C∗-algebras. Mathematics Subject Classifications (2000): 19K35, 46L80, 46L35.
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