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A notion of stratification is introduced for any compactly generated triangulated category T endowed with an action of a graded commutative noetherian ring R. The utility of this notion is demonstrated by establishing diverse consequences…

Category Theory · Mathematics 2014-02-26 Dave Benson , Srikanth B. Iyengar , Henning Krause

We study different types of localisations of a commutative noetherian ring. More precisely, we provide criteria to decide: (a) if a given flat ring epimorphism is a universal localisation in the sense of Cohn and Schofield; and (b) when…

Representation Theory · Mathematics 2021-09-10 Lidia Angeleri Hügel , Frederik Marks , Jan Stovicek , Ryo Takahashi , Jorge Vitória

New homotopy invariant finiteness conditions on modules over commutative rings are introduced, and their properties are studied systematically. A number of finiteness results for classical homological invariants like flat dimension,…

Commutative Algebra · Mathematics 2007-05-23 W. Dwyer , J. P. C. Greenlees , S. Iyengar

It is well-known that a class of all modules, which are torsion-free with respect to a set of ideals, is closed under injective envelopes. In this paper, we consider a kind of a dual to this statement - are the divisibility classes closed…

Commutative Algebra · Mathematics 2018-01-09 Michal Hrbek

Let $A$ be a Noetherian domain and $R$ be a finitely generated $A$-algebra. We study several features regarding the generic freeness over $A$ of an $R$-module. For an ideal $I \subset R$, we show that the local cohomology modules ${\rm…

Commutative Algebra · Mathematics 2024-08-14 Yairon Cid-Ruiz , Ilya Smirnov

The aim of this paper is to describe the classes of strongly flat and weakly cotorsion modules with respect to a multiplicative subset or a finite collection of multiplicative subsets in a commutative ring. The strongly flat modules are…

Commutative Algebra · Mathematics 2019-04-08 Leonid Positselski , Alexander Slavik

The aim of these notes is to collect and motivate the basic localization toolbox for the geometric study of ``spaces'', locally described by noncommutative rings and their categories of one-sided modules. We present the basics of Ore…

Quantum Algebra · Mathematics 2009-09-29 Zoran Skoda

Over a commutative noetherian ring $R$ of finite Krull dimension, we show that every complex of flat cotorsion $R$-modules decomposes as a direct sum of a minimal complex and a contractible complex. Moreover, we define the notion of a…

Commutative Algebra · Mathematics 2020-07-22 Tsutomu Nakamura , Peder Thompson

We characterize Ding modules and complexes over Ding-Chen rings. We show that over a Ding-Chen ring R, the Ding projective (resp. Ding injective, resp. Ding flat) R-modules coincide with the Gorenstein projective (resp. Gorenstein…

Commutative Algebra · Mathematics 2015-12-21 James Gillespie

Let $R$ be a commutative Noetherian ring, $M$ a finitely generated $R$-module and $n$ be a non-negative integer. In this article, it is shown that there is a finitely generated submodule $N_i$ of $H_{\frak a}^i(M)$ such that $\dim{\rm Supp…

Commutative Algebra · Mathematics 2018-01-03 Mohammad Reza Doustimehr

Let $R$ be a noetherian commutative ring, and \[ \mathbb F: ...\rightarrow F_2\rightarrow F_1\rightarrow F_0\rightarrow 0 \] a complex of flat $R$-modules. We prove that if $\kappa(\mathfrak p)\otimes_R\mathbb F$ is acyclic for every…

Commutative Algebra · Mathematics 2010-12-08 Mitsuyasu Hashimoto

We make use of the concepts of Tor-rigid and rigid-test modules, among others, to investigate the interplay between cohomology vanishing and the finiteness of several homological dimensions such as projective, injective and Gorenstein…

Commutative Algebra · Mathematics 2022-12-22 Victor H. Jorge-Pérez , Cleto B. Miranda-Neto

Let f: A\to B be a ring homomorphism between Noetherian normal integral domains. We establish a general criterion for f to induce a homomorphism Cl(f): Cl(A)\to Cl(B) on divisor class groups. For instance, this criterion applies whenever f…

Commutative Algebra · Mathematics 2009-05-26 Sean Sather-Wagstaff , Sandra Spiroff

A 2009 paper by Iacob and Iyengar characterizes noetherian regular rings in terms of properties of complexes of projective modules, flat modules, and injective modules. We show that the relevant properties of such complexes are equivalent…

Rings and Algebras · Mathematics 2026-01-27 Lars Winther Christensen , Sergio Estrada , Peder Thompson

Let $R$ be a commutative Noetherian local ring and let $M$ and $N$ be nonzero finitely generated $R$-modules. In this paper, we investigate how the finiteness of the homological dimension of Ext modules between $M$ and $N$ affects that of…

Commutative Algebra · Mathematics 2025-09-08 Kaito Kimura

In this paper, we study Serre's condition $(S_n)$ for tensor products of modules over a commutative noetherian local ring. The paper aims to show the following. Let $M$ and $N$ be finitely generated module over a commutative noetherian…

Commutative Algebra · Mathematics 2020-02-28 Hiroki Matsui

For a ring $A$, we consider the question whether every bounded above cochain complex of injective $A$-modules which is acyclic is null-homotopic. We show that if $A$ is left and right noetherian and has a dualizing complex, then this…

Rings and Algebras · Mathematics 2023-03-31 Liran Shaul

In this paper, we aim to obtain some results under the condition that the dual of a module over a commutative Noetherian ring has finite Gorenstein dimension. In this direction, we derive results involving vanishing of Ext as well as the…

Commutative Algebra · Mathematics 2025-11-07 Victor D. Mendoza-Rubio , Victor H. Jorge-Pérez

In this paper we present a systematic study of the reflexivity properties of homologically finite complexes with respect to semidualizing complexes in the setting of nonlocal rings. One primary focus is the descent of these properties over…

Commutative Algebra · Mathematics 2007-05-23 Anders Frankild , Sean Sather-Wagstaff

We determine the composition factors of the tensor product $S(E)\otimes S(E)$ of two copies of the symmetric algebra of the natural module $E$ of a general linear group over an algebraically closed field of positive characteristic. Our main…

Representation Theory · Mathematics 2017-04-11 Stephen Donkin , Haralampos Geranios