A Geometric Description of Equivariant K-Homology for Proper Actions
نویسندگان
چکیده
LetG be a discrete group and letX be aG-finite, properG-CW-complex. We prove that Kasparov’s equivariant K-homology groups KK∗ (C0(X),C) are isomorphic to the geometric equivariant K-homology groups of X that are obtained by making the geometric K-homology theory of Baum and Douglas equivariant in the natural way. This reconciles the original and current formulations of the Baum-Connes conjecture for discrete groups. Dedicated with admiration and affection to Alain Connes on his 60th birthday.
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