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Related papers: Local rings of countable Cohen--Macaulay type

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A result of Watanabe and Yoshida says that an unmixed local ring of positive characteristic is regular if and only if its Hilbert-Kunz multiplicity is one. We show that, for fixed $p$ (characteristic) and $d$ (dimension), there exist a…

Commutative Algebra · Mathematics 2007-05-23 Manuel Blickle , Florian Enescu

The multiplicity conjecture of Herzog, Huneke, and Srinivasan is verified for the face rings of the following classes of simplicial complexes: matroid complexes, complexes of dimension one and two, and Gorenstein complexes of dimension at…

Commutative Algebra · Mathematics 2007-05-23 Isabella Novik , Ed Swartz

For a wide class of Cohen--Macaulay modules over the local ring of the plane curve singularity of type T_44 we explicitly describe the corresponding matrix factorizations. The calculations are based on the technique of matrix problems, in…

Commutative Algebra · Mathematics 2022-07-27 Yuriy Drozd , Oleksiy Tovpyha

It is shown that a local ring R of bounded module type is an almost maximal valuation ring if there exists a non-maximal prime ideal J such that R/J is a maximal valuation domain.

Rings and Algebras · Mathematics 2007-05-23 Francois Couchot

By a theorem of Roberts, the integral closure of a regular local ring in a finite abelian extension of its fraction field is Cohen-Macaulay, provided that the degree of the extension is coprime to the characteristic of the residue field. We…

Commutative Algebra · Mathematics 2026-02-06 Aryaman Maithani , Anurag K. Singh , Prashanth Sridhar

In this work we provide an upper bound for the multiplicity of a one-dimensional Cohen-Macaulay ring (under certain conditions), describe the rings attaining the equality for this bound, and outline a connection with Wilf's conjecture for…

Commutative Algebra · Mathematics 2025-05-15 Marco D'Anna , Alessio Moscariello

Auslander and Buchweitz have proved that every finitely generated module over a Cohen-Macaulay (CM) ring with a dualizing module admits a so-called maximal CM approximation. In terms of relative homological algebra, this means that every…

Commutative Algebra · Mathematics 2014-10-22 Henrik Holm

In this paper, we introduce a topology on the set of isomorphism classes of finitely generated modules over an associative algebra. Then we focus on the relative topology on the set of isomorphism classes of maximal Cohen--Macaulay modules…

Commutative Algebra · Mathematics 2019-04-15 Naoya Hiramatsu , Ryo Takahashi

We lay down the fundations of the theory of groups of finite Morley rank in which local subgroups are solvable and we proceed to the local analysis of these groups. We prove the main Uniqueness Theorem, analogous to the Bender method in…

Group Theory · Mathematics 2008-03-27 Adrien Deloro , Eric Jaligot

In this article, we prove a strong version of local Bertini theorem for normality on local rings in mixed characteristic. The main result asserts that a generic hyperplane section of a normal, Cohen-Macaulay, and complete local domain of…

Number Theory · Mathematics 2015-06-18 Tadashi Ochiai , Kazuma Shimomoto

We study K_2 of one-dimensional local domains over a field of characteristic 0, introduce a conjecture, and show that this conjecture implies Geller's conjecture. We also show that Berger's conjecture implies Geller's conjecture, and hence…

K-Theory and Homology · Mathematics 2007-05-23 Amalendu Krishna

In this paper we present characterizations of sequentially Cohen-Macaulay modules in terms of systems of parameters, which are generalizations of well-known results on Cohen-Macaulay and generalized Cohen-Macaulay modules. The sequentially…

Commutative Algebra · Mathematics 2007-05-23 Nguyen Tu Cuong , Doan Trung Cuong

The aim of this survey is to discuss invariants of Cohen-Macaulay local rings that admit a canonical module. Attached to each such ring R with a canonical ideal C, there are integers--the type of R, the reduction number of C--that provide…

Commutative Algebra · Mathematics 2020-06-26 J. P. Brennan , L. Ghezzi , J. Hong , L. Hutson , W. V. Vasconcelos

The aim of this paper is to extend the main result of C. Huneke and G. Lyubeznik in [Adv. Math. 210 (2007), 498--504] to the class of rings that are images of Cohen-Macaulay local rings. Namely, let $R$ be a local Noetherian domain of…

Commutative Algebra · Mathematics 2016-03-15 Pham Hung Quy

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

We present a short proof of Reisner's Theorem, characterizing which simplicial complexes have a Cohen-Macaulay face ring. In some cases, we can also express some homological invariants of the face ring in terms of the reduced homology of…

Commutative Algebra · Mathematics 2016-09-07 Silvano Baggio

In this paper, we prove several results on the finiteness of local cohomology of polynomial and formal power series rings. In particular, we give a partial affirmative answer for a question of L. N\'{u}\~{n}ez-Betancourt in [J. Algebra 399…

Commutative Algebra · Mathematics 2016-08-04 Pham Hung Quy

We prove that certain class of Stanley--Reisner rings having sufficiently large multiplicities are Cohen--Macaulay using Alexander duality.

Commutative Algebra · Mathematics 2007-05-23 Naoki Terai , Ken-ichi Yoshida

We analyze whether Ulrich modules, not necessarily maximal CM (Cohen-Macaulay), can be used as test modules, which detect finite homological dimensions of modules. We prove that Ulrich modules over CM local rings have maximal complexity and…

Commutative Algebra · Mathematics 2023-10-18 Souvik Dey , Dipankar Ghosh

Let $R$ be a Cohen-Macaulay local domain. In this paper we study the cone of Cohen-Macaulay modules inside the Grothendieck group of finitely generated $R$-modules modulo numerical equivalences, introduced in \cite{CK}. We prove a result…

Commutative Algebra · Mathematics 2014-12-09 Hailong Dao , Kazuhiko Kurano