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Twisted K-theory and obstructions against positive scalar curvature metrics

Published online by Cambridge University Press:  17 April 2014

Ulrich Pennig*
Affiliation:
Mathematisches Institut, Westfälische Wilhelms-Universität Münster, Einsteinstraße 62, 48149 Münster, Germany, u.pennig@uni-muenster.de
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Abstract

We decompose θ(M), the twisted index obstruction to a positive scalar curvature metric for closed oriented manifolds with spin universal cover, into a pairing of a twisted K-homology with a twisted K-theory class and prove that θ(M) does not vanish if M is a closed orientable enlargeable manifold with spin universal cover.

Type
Research Article
Copyright
Copyright © ISOPP 2014 

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