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arXiv · 1704.06552

On the anti-Yetter-Drinfeld module-contramodule correspondence

Ilya Shapiro
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Abstract

We study a functor from anti-Yetter Drinfeld modules to contramodules in the case of a Hopf algebra $H$. Some byproducts of this investigation are the establishment of sufficient conditions for this functor to be an equivalence, verification that the center of the opposite category of $H$-comodules is equivalent to anti-Yetter Drinfeld modules, and the observation of two types of periodicities of the generalized Yetter-Drinfeld modules introduced previously. Finally, we give an example of a symmetric $2$-contratrace on $H$-comodules that does not arise from an anti-Yetter Drinfeld module.

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Ilya Shapiro. 2017-04-21. On the anti-Yetter-Drinfeld module-contramodule correspondence. https://arxiv.org/abs/1704.06552

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