Relatively exact modules
Bican, Ladislav
Commentationes Mathematicae Universitatis Carolinae, Tome 44 (2003), p. 569-576 / Harvested from Czech Digital Mathematics Library
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Rim and Teply [10] investigated relatively exact modules in connection with the existence of torsionfree covers. In this note we shall study some properties of the lattice $\Cal E_{\tau}(M)$ of submodules of a torsionfree module $M$ consisting of all submodules $N$ of $M$ such that $M/N$ is torsionfree and such that every torsionfree homomorphic image of the relative injective hull of $M/N$ is relatively injective. The results obtained are applied to the study of relatively exact covers of torsionfree modules. As an application we also obtain some new characterizations of perfect torsion theories.

Publié le : 2003-01-01
Classification:  16D50,  16D80,  16S90,  18E40 
@article{119411,
     author = {Ladislav Bican},
     title = {Relatively exact modules},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {44},
     year = {2003},
     pages = {569-576},
     zbl = {1101.16023},
     mrnumber = {2062873},
     language = {en},
     url = {http://dml.mathdoc.fr/item/119411}
}

Bican, Ladislav. Relatively exact modules. Commentationes Mathematicae Universitatis Carolinae, Tome 44 (2003) pp. 569-576. http://gdmltest.u-ga.fr/item/119411/

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