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Adjoint and Frobenius Pairs of Functors for Corings

M. Zarouali-Darkaoui
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Abstract

We investigate adjoint and Frobenius pairs between categories of comodules over rather general corings. We particularize to the case of the adjoint pair of functors associated to a morphism of corings over different base rings, which leads to a reasonable notion of Frobenius coring extension. When applied to corings stemming from entwining structures, we obtain new results in this setting and in graded ring theory.

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M. Zarouali-Darkaoui. 2005-05-25. Adjoint and Frobenius Pairs of Functors for Corings. https://arxiv.org/abs/math/0505478

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