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Related papers: Multigraded regularity: syzygies and fat points

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The aim of this paper is to introduce a method for computing Hilbert decompositions (and consequently the Hilbert depth) of a finitely generated multigraded module $M$ over the polynomial ring $K[X_1,..., X_n]$ by reducing the problem to…

Commutative Algebra · Mathematics 2013-10-22 Bogdan Ichim , Julio José Moyano-Fernández

Let $B$ denote the upper triangular subgroup of $SL_2(C)$, $T$ its diagonal torus and $U$ its unipotent radical. A complex projective variety $Y$ endowed with an algebraic action of $B$ such that the fixed point set $Y^U$ is a single point,…

Algebraic Geometry · Mathematics 2007-05-23 Michel Brion , James B. Carrell

In this paper we give bounds on the Castelnuovo-Mumford regularity of products of ideals and ideal sheaves. In particular, we show that the regularity of a product of ideals is bounded by the sum of the regularities of its factors if the…

Algebraic Geometry · Mathematics 2007-05-23 Jessica Sidman

We compare, for smooth monomial projective curves, the Castel- nuovo-Mumford regularity and the reduction number; we present an example where these two numbers differ. However, we show they coin- cide for a certain class of monomial curves.…

Commutative Algebra · Mathematics 2007-10-25 Michael Hellus , Lê Tuân Hoa , Jürgen Stückrad

In this review article we present regularity properties of generalized functions which are useful in the analysis of non-linear problems. It is shown that Schwartz distributions embedded into our new spaces of generalized functions, with…

Functional Analysis · Mathematics 2014-07-25 Stevan Pilipovic , Dimitris Scarpalezos , Jasson Vindas

Neural codes form an algebraic framework to study the nervous system, and understanding neural codes is a key goal of mathematical neuroscience. Neural rings and ideals are the tools connecting neuroscience and commutative algebra. In this…

Commutative Algebra · Mathematics 2025-11-25 Trung Chau

We give examples of nonsingular curves in projective 3 space such that the regularity of powers of their ideal sheaves are highly nonlinear. This is in constrast to the case of an ideal I in a polynomial ring, where the regularity of I^n is…

Algebraic Geometry · Mathematics 2007-05-23 Steven Dale Cutkosky

We develop a calculus based on graph enumeration for $S_n$-equivariant motivic invariants of graphically stratified moduli spaces. We apply our theory to the Deligne--Mumford moduli space $\overline{\mathcal{M}}_{g, n}$ and to the space of…

Algebraic Geometry · Mathematics 2025-10-09 Siddarth Kannan , Terry Dekun Song

We prove the regularity conjecture, namely Eisenbud-Goto conjecture, for a normal surface with rational, Gorenstein elliptic and log canonical singularities. Along the way, we bound the regularity for a dimension zero scheme by its Loewy…

Algebraic Geometry · Mathematics 2015-08-11 Wenbo Niu

In this article, firstly, some simple and smoothness properties of the weighted numerical radius and the weighted Crawford number functions are investigated. Then, some generalization formulas for lower and upper bounds of the weighted…

Functional Analysis · Mathematics 2024-12-31 Zameddin I. Ismailov , Pembe Ipek Al

The aim of this paper is to start a systematic investigation of the arithmetic degree of projective schemes as introduced by D. Bayer and D. Mumford. One main theme concerns itself with the behaviour of this arithmetic degree under…

alg-geom · Mathematics 2008-02-03 Chikashi Miyazaki , Wolfgang Vogel

We give an explicit formula for the degree of the Grothendieck polynomial of a Grassmannian permutation and a closely related formula for the Castelnuovo-Mumford regularity of the Schubert determinantal ideal of a Grassmannian permutation.…

Combinatorics · Mathematics 2020-07-30 Jenna Rajchgot , Yi Ren , Colleen Robichaux , Avery St. Dizier , Anna Weigandt

We study Hilbert functions of certain non-reduced schemes A supported at finite sets of points in projective space, in particular, fat point schemes. We give combinatorially defined upper and lower bounds for the Hilbert function of A using…

Algebraic Geometry · Mathematics 2010-12-14 Susan Cooper , Brian Harbourne , Zach Teitler

We compute the Hilbert series of the graded algebra of regular functions on a symplectic quotient of a unitary circle representation. Additionally, we elaborate explicit formulas for the lowest coefficients of the Laurent expansion of such…

Symplectic Geometry · Mathematics 2014-06-27 Hans-Christian Herbig , Christopher Seaton

The definition of the Ponzano-Regge state-sum model of three-dimensional quantum gravity with a class of local observables is developed. The main definition of the Ponzano-Regge model in this paper is determined by its reformulation in…

General Relativity and Quantum Cosmology · Physics 2009-07-22 John W. Barrett , Ileana Naish-Guzman

In this work, we prove that if a graded, commutative algebra $R$ over a field $k$ is not Koszul then, denoting by $\mathfrak{m}$ the maximal homogeneous ideal of $R$ and by $M$ a finitely generated graded $R$-module, the nonzero modules of…

Commutative Algebra · Mathematics 2018-09-28 Luigi Ferraro

Regular and higher regular graded algebras (in simplest case satisfying Von Neumann regularity $\Theta_{1}\Theta_{2}\Theta_{1}=\Theta_{1}$ instead of anticommutativity) are introduced and their properties are studied. They are described in…

Quantum Algebra · Mathematics 2007-05-23 Steven Duplij , Wladyslaw Marcinek

In this article, we give a complete characterization of semigroup graded rings which are graded von Neumann regular. We also demonstrate our results by applying them to several classes of examples, including matrix rings and groupoid graded…

Rings and Algebras · Mathematics 2022-11-30 Daniel Lännström , Johan Öinert

In this paper we show that the sets of $F$-jumping coefficients of ideals form discrete sets in certain graded $F$-finite rings. We do so by giving a criterion based on linear bounds for the growth of the Castelnuovo-Mumford regularity of…

Commutative Algebra · Mathematics 2012-07-13 Mordechai Katzman , Wenliang Zhang

We introduce the good Hilbert functor and prove that it is algebraic. This functor generalizes various versions of the Hilbert moduli problem, such as the multigraded Hilbert scheme and the invariant Hilbert scheme. Moreover, we generalize…

Algebraic Geometry · Mathematics 2016-11-04 Gustav Sædén Ståhl