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JOURNALS // Buletinul Academiei de Ştiinţe a Republicii Moldova. Matematica // Archive

Bul. Acad. Ştiinţe Repub. Mold. Mat., 2018 Number 2, Pages 101–112 (Mi basm477)

Research articles

Closure operators in modules and adjoint functors, II

A. I. Kashu

Institute of Mathematics and Computer Science, Academy of Sciences of Moldova, 5 Academiei str., Chişinău, MD-2028, Moldova

Abstract: In this work we study the relations between the closure operators of two module categories connected by two adjoint contravariant functors. The present article is a continuation of the paper [1] (Part I), where the same question is investigated in the case of two adjoint covariant functors.
An arbitrary bimodule $_RU_S$ defines a pair of adjoint contravariant functors $H_1=Hom_R(\text{-},U)\colon R\text{-}\mathrm{Mod}\to\mathrm{Mod}\text{-}S$ and $H_2=Hom_S(\text{-},U)\colon\mathrm{Mod}\text{-}S\to R\text{-}\mathrm{Mod}$ with two associated natural transformations .png and .png. In this situation we study the connections between the closure operators of the categories $R\text{-}\mathrm{Mod}$ and $\mathrm{Mod}\text{-}S$.

Keywords and phrases: category of modules, closure operator, adjoint functors, contravariant functor.

MSC: 16D90, 16S90, 16A40

Received: 08.05.2018

Language: English



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