We present a classification of those finite length modules X over a ring A that are isomorphic to every module Y of the same length such that Ker(HomA(-,X)) = Ker(HomA(-, Y )), that is, X is determined by its length and the torsion pair cogenerated by X. We also prove the dual result using the torsion pair generated by X. For the case when A is right hereditary, we prove an analogous classification using the cotorsion pair generated by X, but show that the dual result is not provable in ZFC.
© 2008-2024 Fundación Dialnet · Todos los derechos reservados