Corings with decomposition and semiperfect corings
Rings and Algebras
2009-02-16 v1 Category Theory
Abstract
We give a characterization, in terms of Galois infinite comatrix corings, of the corings that decompose as a direct sum of left comodules which are finitely generated as left modules. Then we show that the associated rational functor is exact. This is the case of a right semiperfect coring which is locally projective and whose Galois comodule is a projective left unital module with superfluous radical.
Cite
@article{arxiv.0902.2273,
title = {Corings with decomposition and semiperfect corings},
author = {L. El Kaoutit and J. Gómez-Torrecillas},
journal= {arXiv preprint arXiv:0902.2273},
year = {2009}
}