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arXiv · 1002.0098

Characteristic classes for cohomology of split Hopf algebra extensions

Dieter Degrijse·Nansen Petrosyan
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Abstract

We introduce characteristic classes for the spectral sequence associated to a split short exact sequence of Hopf algebras. We show that these characteristic classes can be seen as obstructions for the vanishing of differentials in the spectral sequence and prove a decomposition theorem. We also interpret our results in the settings of group and Lie algebra extensions and prove some interesting corollaries concerning the collapse of the (Lyndon-)Hochschild-Serre spectral sequence and the order of characteristic classes.

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Dieter Degrijse, Nansen Petrosyan. 2010-01-31. Characteristic classes for cohomology of split Hopf algebra extensions. https://arxiv.org/abs/1002.0098

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