Epis and monos which must be isos.
In this article, we study modules with the weak -extending property. We prove that if satisfies weak -extending, pseudo duo, properties and has finite uniform dimension then decomposes into a direct sum of a semisimple submodule and a submodule of finite uniform dimension. In particular, if satisfies the weak -extending, pseudo duo, properties and ascending (or descending) chain condition on essential submodules then for some semisimple submodule and Noetherian (or Artinian, respectively)...
Let be a ring. A left -module is called an FC-module if is a flat right -module. In this paper, some homological properties of FC-modules are given. Let be a nonnegative integer and the class of all left -modules such that the flat dimension of is less than or equal to . It is shown that is a complete cotorsion pair and if is a ring such that and is closed under direct sums, then is a perfect cotorsion pair. In particular, some known results are obtained as corollaries....
Lattices of submodules of modules and the operators we can define on these lattices are useful tools in the study of rings and modules and their properties. Here we shall consider some submodule operators defined by sets of left ideals. First we focus our attention on the relationship between properties of a set of ideals and properties of a submodule operator it defines. Our second goal will be to apply these results to the study of the structure of certain classes of rings and modules. In particular...
We study whether the projective and injective properties of left -modules can be implied to the special kind of left -modules, especially to the case of inverse polynomial modules and Laurent polynomial modules.
For an arbitrary infinite cardinal , we define classes of -cslender and -tslender modules as well as related classes of -hmodules and initiate a study of these classes.