On generalizations of semiperfect and perfect rings

Document Type : Research Paper

Author

Department of Mathematics, Sinop University, 57000, Sinop, Turkey.

Abstract

‎We call a ring $R$ right generalized semiperfect if every simple right $R$-module is an epimorphic image of a flat right $R$-module with small kernel‎, ‎that is‎, ‎every simple right $R$-module has a flat $B$-cover‎. ‎We give some properties of such rings along with examples‎. ‎We introduce flat strong covers as flat covers which are also flat $B$-covers and give characterizations of $A$-perfect‎, ‎$B$-perfect and perfect rings in terms of flat strong covers.

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Main Subjects


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