[图书][B] Semilocal categories and modules with semilocal endomorphism rings

A Facchini - 2019 - Springer
Let R be an associative ring. This monograph deals with the right R-modules MR whose
endomorphism ring End (MR) is semilocal. More generally, let A be any preadditive …

On the arithmetic of Krull monoids with infinite cyclic class group

A Geroldinger, DJ Grynkiewicz, GJ Schaeffer… - Journal of Pure and …, 2010 - Elsevier
Let H be a Krull monoid with infinite cyclic class group G and let GP⊂ G denote the set of
classes containing prime divisors. We study under which conditions on GP some of the main …

[PDF][PDF] Automorphism-invariant modules

A Alahmadi, A Facchini, N Khanh Tung - Rendiconti del Seminario …, 2015 - numdam.org
A module M is called automorphism-invariant if it is invariant under automorphisms of its
injective envelope. In this paper, we study the endomorphism rings of automorphism …

Equivalence of diagonal matrices over local rings

B Amini, A Amini, A Facchini - Journal of Algebra, 2008 - Elsevier
It is proved that two diagonal matrices diag (a1,…, an) and diag (b1,…, bn) over a local ring
R are equivalent if and only if there are two permutations σ, τ of {1, 2,…, n} such that …

Direct-sum decompositions of modules with semilocal endomorphism rings

A Facchini - Bulletin of Mathematical Sciences, 2012 - Springer
According to the classical Krull–Schmidt Theorem, any module of finite composition length
decomposes as a direct sum of indecomposable modules in an essentially unique way, that …

Kernels of morphisms between indecomposable injective modules

A Facchini, Ş Ecevit, MT Koşan - Glasgow Mathematical Journal, 2010 - cambridge.org
We show that the endomorphism rings of kernels ker ϕ of non-injective morphisms ϕ
between indecomposable injective modules are either local or have two maximal ideals, the …

Endomorphism rings with finitely many maximal right ideals

A Facchini, P Příhoda - Communications in Algebra, 2011 - Taylor & Francis
We show that the indecomposable R-modules whose endomorphism ring has finitely many
maximal right ideals, all of them two-sided, have a surprisingly simple behavior as far as …

Big projective modules over noetherian semilocal rings

D Herbera, P Příhoda - 2010 - degruyter.com
We prove that for a noetherian semilocal ring R with exactly k isomorphism classes of simple
right modules the monoid V*(R) of isomorphism classes of countably generated projective …

Representations of additive categories and direct-sum decompositions of objects

A Facchini - Indiana University mathematics journal, 2007 - JSTOR
The aim of this paper is to embed additive categories in which direct-sum decompositions
into indecomposables are not unique but have a regular geometric behavior into categories …

Couniformly presented modules and dualities

A Facchini, N Girardi - Advances in ring theory, 2010 - Springer
A module UR is couniform if it has dual Goldie dimension 1, that is, it is non-zero and the
sum of any two proper submodules of UR is a proper submodule of UR. A module MR is …