Paschke duality and assembly maps

Abstract

We construct a natural transformation between two versions of $G$-equivariant $K$-homology with coefficients in a $G$-$C^{\ast }$-category for a countable discrete group $G$. Its domain is a coarse geometric $K$-homology and its target is the usual analytic $K$-homology. Following classical terminology, we call this transformation the Paschke transformation. We show that under certain finiteness assumptions on a $G$-space $X$, the Paschke transformation is an equivalence on $X$. As an application, we provide a direct comparison of the homotopy theoretic Davis-Lück assembly map with Kasparov's analytic assembly map appearing in the Baum-Connes conjecture.

139 p major revision