1. Modules in Which Inverse Images of Some Submodules are Direct Summands
- Author
-
Abdullah Harmanci, Sait Halicioglu, and Burcu Ungor
- Subjects
Discrete mathematics ,Algebra and Number Theory ,010102 general mathematics ,Inverse ,010103 numerical & computational mathematics ,0101 mathematics ,Invariant (mathematics) ,01 natural sciences ,Mathematics - Abstract
Let R be an arbitrary ring with identity and M a right R-module with S = EndR(M). Let F be a fully invariant submodule of M. We call M an F-inverse split module if f−1(F) is a direct summand of M for every f ∈ S. This work is devoted to investigation of various properties and characterizations of an F-inverse split module M and to show, among others, the following results: (1) the module M is F-inverse split if and only if M = F ⊕ K where K is a Rickart module; (2) for every free R-module M, there exists a fully invariant submodule F of M such that M is F-inverse split if and only if for every projective R-module M, there exists a fully invariant submodule F of M such that M is F-inverse split; and (3) Every R-module M is Z2(M)-inverse split and Z2(M) is projective if and only if R is semisimple.
- Published
- 2016