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Related papers: Approximations by maximal Cohen-Macaulay modules

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This paper shows that Cohen-Macaulay algebras can be algebraically approximated in such a way that their Cohen-Macaulayness and minimal Betti numbers are preserved. This is achieved by showing that finitely generated modules over power…

Commutative Algebra · Mathematics 2022-04-26 Aftab Patel

This paper deals with computing the global dimension of endomorphism rings of maximal Cohen--Macaulay (=MCM) modules over commutative rings. Several examples are computed. In particular, we determine the global spectra, that is, the sets of…

Representation Theory · Mathematics 2015-10-06 Brandon Doherty , Eleonore Faber , Colin Ingalls

We determine, up to isomorphism, the indecomposable maximal Cohen-Macaulay modules over certain complete one-dimensional local rings of finite Cohen-Macaulay type. We then investigate the direct sum relations of maximal Cohen-Macaulay…

Commutative Algebra · Mathematics 2007-05-23 Nicholas Baeth

In this thesis, the class of modules whose Cousin complexes have finitely generated cohomologies are studied as a subclass of modules which have uniform local cohomological annihilators and it is shown that these two classes coincide over…

Commutative Algebra · Mathematics 2011-07-12 Raheleh Jafari

We introduce a similarity relation between submodules of a module $M$ over a ring $R$, extending the classical notion of similarity for right ideals. Focusing on (faithfully) projective modules, we establish a sharp lower bound for the…

Rings and Algebras · Mathematics 2026-04-07 Alborz Azarang

Let $R$ be a commutative noetherian local differential graded (DG) ring. In this paper we propose a definition of a maximal Cohen-Macaulay DG-complex over $R$ that naturally generalizes a maximal Cohen-Macaulay complex over a noetherian…

Commutative Algebra · Mathematics 2026-03-16 Zachary Nason

Using the theory of cohomology annihilators, we define a family of topologies on the set of isomorphism classes of maximal Cohen-Macaulay modules over a Gorenstein ring. We study compactness of these topologies.

Commutative Algebra · Mathematics 2022-10-10 Mert Akdenizli , Bilal Aytekin , Baran Çetin , Özgür Esentepe

Let R be a Cohen-Macaulay ring and M a maximal Cohen-Macaulay R-module. Inspired by recent striking work by Iyama, Burban-Iyama-Keller-Reiten and Van den Bergh we study the question of when the endomorphism ring of M has finite global…

Commutative Algebra · Mathematics 2010-05-31 Hailong Dao , Craig Huneke

In this article, we show test properties, in the sense of finitely many vanishing of Ext or Tor, of CM (Cohen-Macaulay) modules whose multiplicity and number of generators (resp., type) are related by certain inequalities. We apply these…

Commutative Algebra · Mathematics 2026-01-16 Souvik Dey , Dipankar Ghosh , Aniruddha Saha

We study Hilbert functions of maximal Cohen-Macaulay(=CM) modules over CM local rings. We show that if $A$ is a hypersurface ring with dimension $d > 0$ then the Hilbert function of $M$ \wrt $\m$ is non-decreasing. If $A = Q/(f)$ for some…

Commutative Algebra · Mathematics 2007-05-23 Tony J. Puthenpurakal

A construction due to Kn\"orrer shows that if $N$ is a maximal Cohen-Macaulay module over a hypersurface defined by $f+y^2$, then the first syzygy of $N/yN$ decomposes as the direct sum of $N$ and its own first syzygy. This was extended by…

Representation Theory · Mathematics 2018-03-22 Alex S. Dugas , Graham J. Leuschke

We study properties of graded maximal Cohen-Macaulay modules over an N-graded locally finite, Auslander Gorenstein, and Cohen-Macaulay algebra of dimension two. As a consequence, we extend a part of McKay correspondence in dimension two to…

Rings and Algebras · Mathematics 2019-06-18 Xiaoshan Qin , Yanhua Wang , James Zhang

Let $R$ be a commutative Noetherian local ring. We prove that the finiteness of the injective dimension of a finitely generated $R$-module $C$ is determined by the existence of a Cohen--Macaulay module $M$ that satisfies an inequality…

Commutative Algebra · Mathematics 2025-04-11 Shinnosuke Kosaka , Yuki Mifune , Kenta Shimizu

Let $(R, \frak m)$ be a homomorphic image of a Cohen-Macaulay local ring and $M$ a finitely generated $R$-module. We use the splitting of local cohomology to shed a new light on the structure of non-Cohen-Macaulay modules. Namely, we show…

Commutative Algebra · Mathematics 2025-05-20 Nguyen Tu Cuong , Pham Hung Quy

Finitely generated reflexive modules over commutative Noetherian rings form a key component of Auslander and Bridger's stable module theory and are likewise essential in the study of Cohen--Macaulay representations. Recently, H. Dao…

Commutative Algebra · Mathematics 2025-05-23 Souvik Dey

We classify all tilting and cotilting classes over commutative noetherian rings in terms of descending sequences of specialization closed subsets of the Zariski spectrum. Consequently, all resolving subcategories of finitely generated…

Commutative Algebra · Mathematics 2014-06-03 Lidia Angeleri Hügel , David Pospisil , Jan Stovicek , Jan Trlifaj

The third named author and P\'{e}rez proved that under certain conditions the test ideal of a module closure agrees with the trace ideal of the module closure. We use this fact to compute the test ideals of various rings with respect to the…

Commutative Algebra · Mathematics 2021-03-04 Julian Benali , Shrunal Pothagoni , Rebecca R. G.

The author establishes finite-generation of the cohomology ring of a classical Lie superalgebra relative to an even subsuperalgebra. A spectral sequence is constructed to provide conditions for when this relative cohomology ring is…

Representation Theory · Mathematics 2018-07-30 Andrew Maurer

We show how for a three-dimensional complete local ring in positive characteristic, the existence of an F-invariant, differentiable derivation implies Hochster's small MCM conjecture. As an application we show that any three-dimensional…

Commutative Algebra · Mathematics 2019-11-14 Hans Schoutens

Let R be a commutative noetherian local ring. A finitely generated R-module C is semidualizing if it is self-orthogonal and satisfies the condition Hom_R(C,C) \cong R. We prove that a Cohen-Macaulay ring R with dualizing module D admits a…

Commutative Algebra · Mathematics 2009-11-23 David A. Jorgensen , Graham J. Leuschke , Sean Sather-Wagstaff