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A note on coring extensions

Tomasz Brzezinski
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Abstract

A notion of a coring extension is defined and it is related to the existence of an additive functor between comodule categories that factorises through forgetful functors. This correspondence between coring extensions and factorisable functors is illustrated by functors between categories of descent data. A category in which objects are corings and morphisms are coring extensions is also introduced.

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Tomasz Brzezinski. 2008-07-31. A note on coring extensions. https://arxiv.org/abs/math/0410020

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