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Chern character for totally disconnected groups

Christian Voigt
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Abstract

In this paper we construct a bivariant Chern character for the equivariant KK-theory of a totally disconnected group with values in bivariant equivariant cohomology in the sense of Baum and Schneider. We prove in particular that the complexified left hand side of the Baum-Connes conjecture for a totally disconnected group is isomorphic to cosheaf homology. Moreover, it is shown that our transformation extends the Chern character defined by Baum and Schneider for profinite groups.

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Christian Voigt. 2006-08-25. Chern character for totally disconnected groups. https://arxiv.org/abs/math/0608626

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