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Baer's Criterion for Injectivity is a basic tool of the theory of modules and complexes of modules. Its dual version (DBC) is known to hold for all right perfect rings, but its validity for non-right perfect rings is a complex problem…

Representation Theory · Mathematics 2022-05-27 Jan Trlifaj

We are working in the category of commutative unital rings and denote by $\mathrm U(R)$ the group of units of a nonzero ring $R$. An extension of rings $R\subseteq S$, satisfying $\mathrm U(R)=R \cap\mathrm U(S)$ is usually called local.…

Commutative Algebra · Mathematics 2024-11-05 Gabriel Picavet , Martine Picavet L'Hermitte

Let $R$ be a ring. It is proved that an $R$-module $M$ is Baer (resp. dual Baer) if and only if every exact sequence $0\rightarrow X\rightarrow M\rightarrow Y\rightarrow 0$ with $Y\in$ Cog$(M_R)$ (resp. $X\in$ Gen$(M_R)$) splits. This shows…

Rings and Algebras · Mathematics 2020-05-06 N. Ghaedan , M. R. Vedadi

This work is a review of results about centrally essential rings and semirings. A ring (resp., semiring) is said to be centrally essential if it is either commutative or satisfy the property that for any non-central element $a$, there exist…

Rings and Algebras · Mathematics 2022-05-31 Askar Tuganbaev

The purpose of this paper is to give a partial positive answer to a question raised by Khurana et al. as to whether a ring $R$ with stable range one and central units is commutative. We show that this is the case under any of the following…

Rings and Algebras · Mathematics 2019-10-11 Paula A. A. B. Carvalho , Christian Lomp , Jerzy Matczuk

In a pandemic era preprint, Dao showed showed two remarkable properties of Arf rings: under some mild conditions, they admit finitely many indecomposable reflexive modules up to isomorphism and every reflexive module is actually isomorphic…

Commutative Algebra · Mathematics 2025-05-23 Özgür Esentepe

An $S$-ring (a Schur ring) is said to be separable with respect to a class of groups $\mathcal{K}$ if every algebraic isomorphism from the $S$-ring in question to an $S$-ring over a group from $\mathcal{K}$ is induced by a combinatorial…

Group Theory · Mathematics 2019-12-17 Grigory Ryabov

A ring $R$ is said to be centrally essential if for every its non-zero element $a$, there exist non-zero central elements $x$ and $y$ with $ax = y$. A ring $R$ is said to be completely centrally essential if all its factor rings are…

Rings and Algebras · Mathematics 2025-03-27 Oleg Lyubimtsev , Askar Tuganbaev

Any superrosy division ring (i.e. a division ring equipped with an abstract notion of rank) is shown to be centrally finite. Furthermore, division rings satisfying a generalized chain condition on definable subgroups are studied. In…

Logic · Mathematics 2016-05-16 Nadja Hempel , Daniel Palacín

This article studies the notion of $S-r-$ideals in commutative ring $H$, where $S$ is a multiplicatively closed subset of $H$. Some basic properties of $S-r-$ideals are given. Various characterizations of $S-r-$ideals are presented. Also,…

Commutative Algebra · Mathematics 2025-09-16 Abuzer Gündüz , Osama A. Naji , Mehmet Özen

Let $f:S\rightarrow R$ be a ring extension. We introduce and study the properties of $(R, S)_\star$-injective modules and the existences of $(R, S)_\star$-injective envelopes. Besides, we show that every $R$-module has an $(R, S)$-injective…

Rings and Algebras · Mathematics 2024-09-04 Xiaolei Zhang

A new class of rings, the class of left localizable rings, is introduced. A ring $R$ is left localizable if each nonzero element of $R$ is invertible in some left localization $S^{-1}R$ of the ring $R$. Explicit criteria are given for a…

Rings and Algebras · Mathematics 2014-05-20 V. V. Bavula

In this paper we treat Grothendieck Duality for noetherian rings via rigid dualizing complexes. In particular, we prove that every ring, essentially finite type over a regular base ring, has a unique rigid dualizing complex. The rigid…

Algebraic Geometry · Mathematics 2024-02-13 Mattia Ornaghi , Saurabh Singh , Amnon Yekutieli

A commutative noetherian ring with a dualizing complex is Gorenstein if and only if every acyclic complex of injective modules is totally acyclic. We extend this characterization, which is due to Iyengar and Krause, to arbitrary commutative…

Commutative Algebra · Mathematics 2017-02-13 Lars Winther Christensen , Kiriko Kato

We consider in-depth and characterize in certain aspects the class of so-called {\it strongly NUS-nil clean rings}, that are those rings whose non-units are {\it square nil-clean} in the sense that they are a sum of a nilpotent and a…

Rings and Algebras · Mathematics 2025-08-05 Mina Doostalizadeh , Ahmad Moussavi , Peter Danchev

Let $R$ be a commutative $G$-graded ring with a nonzero unity. In this article, we introduce the concept of graded radically principal ideals. A graded ideal $I$ of $R$ is said to be graded radically principal if $Grad(I)=Grad(\langle…

Commutative Algebra · Mathematics 2021-01-06 Rashid Abu-Dawwas

Let $(R, \mathfrak{m})$ be a noetherian local ring, $M$ a separated $R$-module (i.e. $\bigcap\limits_{n\geq 1}\mathfrak{m}^n M = 0$) and $\widehat{M} = \lim\limits_{\leftarrow} M/\mathfrak{m}^n M$ its completion. Generally, $M$ is not pure…

Commutative Algebra · Mathematics 2015-04-02 Helmut Zöschinger

In this paper, we study the rings with zero Gorenstein weak dimensions, which we call them Gorenstein Von Neumann regular rings.

Commutative Algebra · Mathematics 2009-10-27 Najib Mahdou , Mohammed Tamekkante , Siamak Yassemi

We show that a ring $R$ is regular if $Tor_{i}^{R}(R^{+},k) = 0$ for some $i\geq 1$ assuming further that $R$ is a $\mathbb{N}$-graded ring of dimension $2$ finitely generated over an equi-characteristic zero field $k$. This answers a…

Commutative Algebra · Mathematics 2022-12-20 Shravan Patankar

Let S and R be the rings of regular functions on affine algebraic varieties over a field of characteristic 0, R be embedded as a subring in S, and F : S --> S be an endomorphism such that F(R) subset R. Suppose that every ideal of height 1…

Algebraic Geometry · Mathematics 2007-05-23 Shulim Kaliman