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A commutative Noetherian ring $R$ is said to be Tor-persistent if, for any finitely generated $R$-module $M$, the vanishing of $\operatorname{Tor}_i^R(M,M)$ for $i\gg 0$ implies $M$ has finite projective dimension. An open question of…

Commutative Algebra · Mathematics 2024-07-29 Justin Lyle , Jonathan Montaño , Keri Sather-Wagstaff

In this note, finite modules locally of finite injective dimension over commutative Noetherian rings are characterized in terms of vanishing of Ext modules.

Commutative Algebra · Mathematics 2007-05-23 Ryo Takahashi

Let $R\to U$ be an associative ring epimorphism such that $U$ is a flat left $R$-module. Assume that the related Gabriel topology $\mathbb G$ of right ideals in $R$ has a countable base. Then we show that the left $R$-module $U$ has…

Rings and Algebras · Mathematics 2021-09-17 Leonid Positselski

Let $K$ be a commutative Noetherian ring with identity, let $A$ be a $K$-algebra, and let $B$ be a subalgebra of $A$ such that $A/B$ is finitely generated as a $K$-module. The main result of the paper is that $A$ is finitely presented…

Rings and Algebras · Mathematics 2019-02-22 Peter Mayr , Nik Ruskuc

We apply Ohi's criterion for faithfully flatness of extensions of commutative rings to prove that any \'etale extension $k[Y_1, \ldots, Y_n]\subseteq k[X_1, \ldots, X_n]$ of polynomial rings (each in $n$ indeterminates) over a commutative…

Commutative Algebra · Mathematics 2024-03-01 Lázaro O. Rodríguez Díaz

This article investigates strong generation within the module category of a commutative Noetherian ring. We establish a criterion for such rings to possess strong generators within their module category, addressing a question raised by…

Commutative Algebra · Mathematics 2025-08-08 Souvik Dey , Pat Lank , Ryo Takahashi

We apply the theory of cotorsion pairs to study closure properties of classes of modules with finite projective dimension with respect to direct limit operations and to filtrations. We also prove that if the ring is an order in an…

Rings and Algebras · Mathematics 2011-11-10 Silvana Bazzoni , Dolors Herbera

Let R be a commutative ring, M an R-module, and N a finitely presented R-module such that the intersection of Max(R) and Supp(N) is finite-dimensional and Noetherian. Suppose also that N is homothetic; in other words, suppose that the…

Commutative Algebra · Mathematics 2021-08-10 Robin Baidya

In this note we show that a ring R is left perfect if and only if every left R-module is weakly supplemented if and only if R is semilocal and the radical of the countably infinite free left R-module has a weak supplement.

Rings and Algebras · Mathematics 2010-03-18 Engin Büyükaşik , Christian Lomp

If $M$ is a nonzero finitely generated module over a commutative Noetherian local ring $R$ such that $M$ has finite injective dimension and finite Gorenstein dimension, then it follows from a result of Holm that $M$ has finite projective…

Commutative Algebra · Mathematics 2025-02-24 Tokuji Araya , Olgur Celikbas , Jesse Cook , Toshinori Kobayashi

Let $RQ$ be the path algebra of a Dynkin quiver $Q$ over a commutative noetherian ring $R$. We show that any homotopically smashing t-structure in the derived category of $RQ$ is compactly generated. We also give a complete description of…

Representation Theory · Mathematics 2025-05-28 Enrico Sabatini

Using the notion of cyclically pure injective modules, a characterization for rings which are locally valuation is established. As applications, new characterizations for Prufer domains and pure semi-simple rings are provided. Namely, we…

Commutative Algebra · Mathematics 2007-05-23 Kamran Divaani-Aazar , Mohammad Ali Esmkhani , Massoud Tousi

We introduce FI-algebras over a commutative ring $K$ and the category of FI-modules over an FI-algebra. Such a module may be considered as a family of invariant modules over compatible varying $K$-algebras. FI-modules over $K$ correspond to…

Commutative Algebra · Mathematics 2021-05-18 Uwe Nagel , Tim Römer

It is proved that localizations of injective $R$-modules of finite Goldie dimension are injective if $R$ is an arithmetical ring satisfying the following condition: for every maximal ideal $P$, $R_P$ is either coherent or not semicoherent.…

Rings and Algebras · Mathematics 2009-01-13 Francois Couchot

It is proved that localizations of injective $R$-modules of finite Goldie dimension are injective if $R$ is an arithmetical ring satisfying the following condition: for every maximal ideal $P$, $R_P$ is either coherent or not semicoherent.…

Rings and Algebras · Mathematics 2009-10-13 Francois Couchot

The coprimary filtration is a basic construction in commutative algebra. In this article, we prove the existence and uniqueness of coprimary filtration of modules (not necessarily finitely generated) over a Noetherian ring. Moreover, we…

Commutative Algebra · Mathematics 2024-10-16 Yao Li

We study rings over which an analogue of the Weierstrass preparation theorem holds for power series. We show that a commutative ring $R$ admits a factorization of every power series in $R[[x]]$ as the product of a polynomial and a unit if…

Commutative Algebra · Mathematics 2026-02-10 Jason Bell , Peter Malcolmson , Frank Okoh , Yatin Patel

Let $R$ be a commutative noetherian ring, $\frak a$ be an ideal of $R$, $\mathcal{S}$ be an arbitrary Serre subcategory of $R$-modules satisfying the condition $C_{\frak a}$ and let $\mathcal{N}$ be the subcategory of finitely generated…

Commutative Algebra · Mathematics 2022-05-31 Negar Alipour , Reza Sazeedeh

In this paper, we prove "prismatic Kunz's theorem" which states that a complete Noetherian local ring $R$ of residue characteristic $p$ is a regular local ring if and only if the Frobenius lift on a prismatic complex of (a derived…

Commutative Algebra · Mathematics 2026-01-28 Ryo Ishizuka , Kei Nakazato

Let B(X,L,s) be the twisted homogeneous coordinate ring of an irreducible variety X over an algebraically closed field k with dim X > 1. Assume that c in X and s in Aut(X) are in sufficiently general position. We show that if one follows…

Rings and Algebras · Mathematics 2016-09-07 D. S. Keeler , D. Rogalski , J. T. Stafford