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Comatrix corings: Galois corings, Descent Theory, and a Structure Theorem for Cosemisimple corings

L. El Kaoutit·J. Gomez-Torrecillas
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Abstract

In order to extrincate the structure of corings with a finitely generated and projective generator we give the notion of a comatrix coring. As consequences we give generalizations of the main characterizations of faithfully flat Galois corings and extensions which work for corings without grouplike elements, as well as a generalization of the Descent Theorem. We provide also a complete description of all cosemisimple corings. No restrictions are made over the ground noncommutative ring.

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L. El Kaoutit, J. Gomez-Torrecillas. 2002-07-23. Comatrix corings: Galois corings, Descent Theory, and a Structure Theorem for Cosemisimple corings. https://arxiv.org/abs/math/0207205

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