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Group corings

S. Caenepeel·K. Janssen·S. H. Wang
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Abstract

We introduce group corings, and study functors between categories of comodules over group corings, and the relationship to graded modules over graded rings. Galois group corings are defined, and a Structure Theorem for the $G$-comodules over a Galois group coring is given. We study (graded) Morita contexts associated to a group coring. Our theory is applied to group corings associated to a comodule algebra over a Hopf group coalgebra.

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S. Caenepeel, K. Janssen, S. H. Wang. 2007-01-31. Group corings. https://arxiv.org/abs/math/0701931

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