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Let $R$ be a commutative Noetherian ring, $I$ an ideal of $R$ and $M$, $N$ two finitely generated $R$-modules. The aim of this paper is to investigate the $I$-cofiniteness of generalized local cohomology modules $\displaystyle…

Commutative Algebra · Mathematics 2015-11-03 Nguyen Tu Cuong , Shiro Goto , Nguyen Van Hoang

Let $\mathfrak{a}$ be an ideal of a noetherian (not necessarily local) ring $R$ and $M$ an $R$-module with $\mathrm{Supp}_RM\subseteq\mathrm{V}(\mathfrak{a})$. We show that if $\mathrm{dim}_RM\leq2$, then $M$ is $\mathfrak{a}$-cofinite if…

Commutative Algebra · Mathematics 2021-09-13 Xiaoyan Yang , Jingwen Shen

We discuss the Japanese and universally Japanese properties for valuation rings and Pr\"ufer domains. These properties, regarding finiteness of integral closure, have been studied extensively for Noetherian rings, but very rarely, if ever,…

Commutative Algebra · Mathematics 2025-10-13 Shiji Lyu

In this paper, an algebraic theory for local rings of finite embedding dimension is developed. Several extensions of (Krull) dimension are proposed, which are then used to generalize singularity notions from commutative algebra. Finally,…

Commutative Algebra · Mathematics 2014-08-27 Hans Schoutens

Let $R$ be a Noetherian ring, $I$ an ideal of $R$ and $M$ an $R$-module with $\operatorname{cd}(I,M)=c$. In this article, we first show that there exists a descending chain of ideals $I=I_c\supsetneq I_{c-1}\supsetneq \cdots \supsetneq I_0$…

Commutative Algebra · Mathematics 2016-05-16 Vahap Erdoǧdu , Tuǧba Yıldırım

We find necessary and sufficient conditions for a complete local ring containing the rationals to be the completion of a countable excellent local (Noetherian) domain. Furthermore, we find necessary and sufficient conditions for a complete…

Commutative Algebra · Mathematics 2020-05-15 S. Loepp , Teresa Yu

We relate finite generation of cones, monoids, and ideals in increasing chains (the local situation) to equivariant finite generation of the corresponding limit objects (the global situation). For cones and monoids there is no analog of…

Combinatorics · Mathematics 2022-04-26 Thomas Kahle , Dinh Van Le , Tim Römer

This note intended to give a counterexample to a question related to the following theorem. Let D be a differential domain finitely generated over a differential field F with algebraically closed field of constants,C, of characteristic 0.…

Commutative Algebra · Mathematics 2007-05-23 Eloise Hamann

Let $R$ denote a commutative Noetherian (not necessarily local) ring, $\frak a$ an ideal of $R$ and $M$ a finitely generated $R$-module. The purpose of this paper is to show that $f^n_{\frak a}(M)=\inf \{0\leq i\in\mathbb{Z}|\, \dim…

Commutative Algebra · Mathematics 2014-07-03 Ali Akbar Mehrvarz , Reza Naghipour , Monireh Sedghi

For a noetherian ring R we call an R-module M cofinite if there exists an ideal I of R such that M is I-cofinite; we show that every cofinite module M satisfies dim_R(M)<=injdimR(M). As an application we study the question which local…

Commutative Algebra · Mathematics 2007-05-23 Michael Hellus

We show how subintegral extensions of certain local Noetherian domains $S$ can be constructed with specified invariants including reduction number, Hilbert function, multiplicity and local cohomology. The construction behaves analytically…

Commutative Algebra · Mathematics 2013-06-05 Bruce Olberding

We prove that two arbitrary ideals $I \subset J$ in an equidimensional and universally catenary Noetherian local ring have the same integral closure if and only if they have the same multiplicity sequence. We also obtain a Principle of…

Commutative Algebra · Mathematics 2021-10-18 Claudia Polini , Ngo Viet Trung , Bernd Ulrich , Javid Validashti

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 \cite{AB}, the dagger closure is extended over finitely generated modules over Noetherian local domain $(R,\fm)$ and it is proved to be a Dietz closure. In this short note we show that it also satisfies the `Algebra axiom' of \cite{R.G}…

Commutative Algebra · Mathematics 2016-03-30 Rajsekhar Bhattacharyya

The author introduces a conjecture about Makar-Limanov invariants of affine unique factorization domains over a field of characteristic zero. Then the author finds that the conjecture does not always hold when $\mathbbm{k}$ is not…

Commutative Algebra · Mathematics 2020-10-13 Ziqi Liu

Let $(R,m)$ be a local Noetherian ring, let $I\subset R$ be any ideal and let $M$ be a finitely generated $R$-module. In 1990 Craig Huneke conjectured that the local cohomology modules $H^i_I(M)$ have finitely many associated primes for all…

Commutative Algebra · Mathematics 2007-05-23 Mordechai Katzman

Let $R$ be a Mori domain with complete integral closure $\widehat R$, nonzero conductor $\mathfrak f = (R \ :\ \widehat R)$, and suppose that both $v$-class groups $\mathcal C_v (R)$ and $\mathcal C_v (\widehat R)$ are finite. If…

Commutative Algebra · Mathematics 2020-04-15 Qinghai Zhong

Let $T$ be a complete local (Noetherian) ring. For each $i \in \mathbb{N}$, let $C_i$ be a nonempty countable set of nonmaximal pairwise incomparable prime ideals of $T$, and suppose that if $i \neq j$, then either $C_i = C_j$ or no element…

Commutative Algebra · Mathematics 2023-11-28 David Baron , Ammar Eltigani , S. Loepp , AnaMaria Perez , M. Teplitskiy

We find necessary and sufficient conditions for a complete local (Noetherian) ring to be the completion of an uncountable local (Noetherian) domain with a countable spectrum. Our results suggest that uncountable local domains with countable…

Commutative Algebra · Mathematics 2020-05-20 S. Loepp , Teresa Yu

This is a two-part article. In the first part, we study an alternative notion to Nagata rings. A Nagata ring is a Noetherian ring $R$ such that every finite $R$-algebra that is an integral domain has finite normalization. We replace the…

Commutative Algebra · Mathematics 2026-02-20 Shiji Lyu