Flat Strong δ-covers of Modules

Year 2019, , 43 - 52, 01.02.2019

Yılmaz Mehmet Demirci

https://doi.org/10.31801/cfsuasmas.443540

Abstract

We say that a ring R is right generalized δ-semiperfect if every simple right R-module is an epimorphic image of a flat right R-module with δ-small kernel. This definition gives a generalization of both right δ-semiperfect rings and right generalized semiperfect rings. We provide examples involving such rings along with some of their properties. We introduce flat strong δ-cover of a module as a flat cover which is also a flat δ-cover and use flat strong δ-covers in characterizing right A-perfect rings, right B-perfect rings and right perfect rings.

Keywords

Flat cover, flat δ-cover, flat strong δ-cover, G-δ-semiperfect ring, semiperfect ring, perfect ring

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