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arXiv · 0707.3207

Index theory for actions of compact Lie groups on C*-algebras

Charlotte Wahl
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Abstract

We study the index theory for actions of compact Lie groups on C*-algebras with an emphasis on principal actions. Given an invariant semifinite trace on the C*-algebra we obtain semifinite spectral triples. For circle actions we consider the relation to the dual Pimsner-Voiculescu sequence. On the way we show that the notions ``saturated'' and ``principal'' are equivalent for actions by compact Lie groups.

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Charlotte Wahl. 2008-06-28. Index theory for actions of compact Lie groups on C*-algebras. https://arxiv.org/abs/0707.3207

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