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arXiv · 2409.06408

A note on invariants of foliated 3-sphere bundles

Nils Prigge
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Abstract

In this note we prove that $H^*(\text{BSO}(4);\mathbb{Q})$ injects into the group cohomology of $\text{Diff}^+(S^{3})$ with rational coefficients. The proof is based on an idea of Nariman who proved that the monomials in the Euler and Pontrjagin classes are nontrivial in $H^*(\text{BDiff}_+^{\delta}(S^{2n-1});\mathbb{Q})$.

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Nils Prigge. 2024-09-10. A note on invariants of foliated 3-sphere bundles. https://arxiv.org/abs/2409.06408

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