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arXiv · 2403.09371

Rigid secondary characteristic classes

Steven Hurder
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Abstract

We construct families of non-trivial universal rigid secondary classes for foliations, and then discuss their application to prove that foliations are not homotopic. An observation of Lawson about the non-triviality of the normal Pontrjagin classes of foliations is extended, and then used to construct new families of examples of foliations with non-trivial rigid secondary classes. Examples are given of (abstractly constructed) foliations of compact manifolds with homotopic tangent bundles, but which are not homotopic as foliations.

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Steven Hurder. 2024-03-14. Rigid secondary characteristic classes. https://arxiv.org/abs/2403.09371

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