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arXiv · 1811.04603

The Godbillon-Vey invariant in equivariant $KK$-theory

Lachlan MacDonald·Adam Rennie
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Abstract

We construct a groupoid equivariant Kasparov class for transversely oriented foliations in all codimensions. In codimension 1 we show that the Chern character of an associated semifinite spectral triple recovers the Connes-Moscovici cyclic cocycle for the Godbillon-Vey secondary characteristic class.

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BibTeXRIS

Lachlan MacDonald, Adam Rennie. 2019-11-08. The Godbillon-Vey invariant in equivariant $KK$-theory. https://doi.org/10.2140/akt.2020.5.249

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