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arXiv · 1705.07651

Hopf-cyclic cohomology of the Connes-Moscovici Hopf algebras with infinite dimensional coefficients

B. Rangipour·S. Sütlü·F. Yazdani Aliabadi
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Abstract

We discuss a new strategy for the computation of the Hopf-cyclic cohomology of the Connes-Moscovici Hopf algebra $\mathcal{H}_n$. More precisely, we introduce a multiplicative structure on the Hopf-cyclic complex of $\mathcal{H}_n$, and we show that the van Est type characteristic homomorphism from the Hopf-cyclic complex of $\mathcal{H}_n$ to the Gelfand-Fuks cohomology of the Lie algebra $W_n$ of formal vector fields on $\mathbb{R}^n$ respects this multiplicative structure. We then illustrate the machinery for $n=1$.

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B. Rangipour, S. Sütlü, F. Yazdani Aliabadi. 2017-08-15. Hopf-cyclic cohomology of the Connes-Moscovici Hopf algebras with infinite dimensional coefficients. https://arxiv.org/abs/1705.07651

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