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Characters of Fredholm modules and a problem of Connes

Michael Puschnigg
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Abstract

It is shown that Connes' character formula for unbounded, theta-summable Fredholm modules represents the abstract Chern-character in K-homology. As an application, the character of a particular Fredholm module over the reduced group C*-algebra of a discrete group is calculated, which leads to a partial solution of a problem posed by A.Connes.

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Michael Puschnigg. 2006-04-25. Characters of Fredholm modules and a problem of Connes. https://arxiv.org/abs/math/0604528

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