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arXiv · 1503.02347

Hopf algebra $\mathcal{K}_n$ and universal Chern classes

Henri Moscovici·Bahram Rangipour
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Abstract

We construct a variant $\mathcal{K}_n$ of the Hopf algebra $\mathcal{H}_n$, which acts directly on the noncommutative model for the generic space of leaves rather than on its frame bundle. We prove that the Hopf cyclic cohomology of $\mathcal{K}_n$ is isomorphic to that of the pair $(\mathcal{H}_n, {\mathop{\rm GL}_n})$ and thus consists of the universal Hopf cyclic classes. We then realize these classes in terms of geometric cocycles.

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Henri Moscovici, Bahram Rangipour. 2015-03-09. Hopf algebra $\mathcal{K}_n$ and universal Chern classes. https://arxiv.org/abs/1503.02347

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