English
Related papers

Related papers: Generic Cohen-Macaulay monomial ideals

200 papers

We extend the sortability concept to monomial ideals which are not necessarily generated in one degree and as an application we obtain normal Cohen-Macaulay toric rings attached to vertex cover ideals of graphs. Moreover, we consider a…

Commutative Algebra · Mathematics 2022-09-23 Jürgen Herzog , Takayuki Hibi , Somayeh Moradi

It is shown that the deformed Calogero-Moser-Sutherland (CMS) operators can be described as the restrictions on certain affine subvarieties (called generalised discriminants) of the usual CMS operators for infinite number of particles. The…

Mathematical Physics · Physics 2007-05-23 A. N. Sergeev , A. P. Veselov

Let G be a simple undirected graph on n vertices, and let I(G) \subseteq R = k[x_1,...,x_n] denote its associated edge ideal. We show that all chordal graphs G are sequentially Cohen-Macaulay; our proof depends upon showing that the…

Commutative Algebra · Mathematics 2007-06-13 Christopher A. Francisco , Adam Van Tuyl

We compute the deformations in the sense of generalized complex structures of the standard classical complex structure on a primary Kodaira surface and we prove that the obtained family of deformations is a smooth locally complete family…

Algebraic Geometry · Mathematics 2015-05-13 Vasile Brinzanescu , Oana Adela Turcu

We generalise the techniques of arXiv:0908.1963 to describe derived deformations in simplicial categories. This allows us to consider deformation problems with higher automorphisms, such as chain complexes (which have homotopies) and stacks…

Algebraic Geometry · Mathematics 2015-02-03 J. P. Pridham

We describe the typical homological properties of monomial ideals defined by random generating sets. We show that, under mild assumptions, random monomial ideals (RMI's) will almost always have resolutions of maximal length; that is, the…

Commutative Algebra · Mathematics 2018-10-04 Jesús A. De Loera , Serkan Hoşten , Robert Krone , Lily Silverstein

We study rational normal curves via a connection to the chip firing game. A key technique, introduced in this article, is to interpret the defining ideal of the rational normal curve as an ideal associated to a generalisation of a cycle…

Commutative Algebra · Mathematics 2024-11-21 Rahul Karki , Madhusudan Manjunath

We introduce the Macaulay2 package HomologicalShiftIdeals. It allows to compute the homological shift ideals of a monomial ideal, and to check the homological shift properties, including having linear resolution, having linear quotients, or…

Commutative Algebra · Mathematics 2023-09-19 Antonino Ficarra

Call a monomial ideal M "generic" if no variable appears with the same nonzero exponent in two distinct monomial generators. Using a convex polytope first studied by Scarf, we obtain a minimal free resolution of M. Any monomial ideal M can…

alg-geom · Mathematics 2008-02-03 Dave Bayer , Irena Peeva , Bernd Sturmfels

Let $\Delta$ be a one-dimensional simplicial complex. Let $I_\Delta$ be the Stanley-Reisner ideal of $\Delta$. We prove that for all $s \ge 1$ and all intermediate ideals $J$ generated by $I_\Delta^s$ and some minimal generators of…

Commutative Algebra · Mathematics 2021-09-15 Nguyen Cong Minh , Thanh Vu

We establish a uniform bound for the Castelnuovo-Mumford regularity of associated graded rings of parameter ideals in a generalized Cohen-Macaulay ring. As consequences, we obtain uniform bounds for the relation type and the postulation…

Commutative Algebra · Mathematics 2007-05-23 Cao Huy Linh , Ngo Viet Trung

We provide an algorithm that computes a set of generators for any complete ideal in a smooth complex surface. More interestingly, these generators admit a presentation as monomials in a set of maximal contact elements associated to the…

Algebraic Geometry · Mathematics 2017-10-31 Maria Alberich-Carramiñana , Josep Alvarez Montaner , Guillem Blanco

We describe the simplicial complex $\Delta$ such that the initial ideal of $J_G$ is the Stanley-Reisner ideal of $\Delta$. By $\Delta$ we show that if $J_G$ is $(S_2)$ then $G$ is accessible. We also characterize all accessible blocks with…

Commutative Algebra · Mathematics 2021-08-03 Alberto Lerda , Carla Mascia , Giancarlo Rinaldo , Francesco Romeo

We compute the initial ideals, with respect to certain conveniently chosen term orders, of ideals of tangent cones at torus fixed points to Schubert varieties in orthogonal Grassmannians. The initial ideals turn out to be square-free…

Combinatorics · Mathematics 2008-03-16 K. N. Raghavan , Shyamashree Upadhyay

Inspired by the notion of K\"onig graphs we introduce graded ideals of K\"onig type with respect to a monomial order $<$. It is shown that if $I$ is of K\"onig type, then the Cohen--Macaulay property of $\ini_<(I)$ does not depend on the…

Commutative Algebra · Mathematics 2021-03-16 Jürgen Herzog , Takayuki Hibi , Somayeh Moradi

We study properties of the Stanley-Reisner rings of simplicial complexes with isolated singularities modulo two generic linear forms. Miller, Novik, and Swartz proved that if a complex has homologically isolated singularities, then its…

Commutative Algebra · Mathematics 2017-03-21 Connor Sawaske

In this article we study the structure of residual intersections via constructing a finite complex which is acyclic under some sliding depth conditions on the cycles of the Koszul complex. This complex provides information on an ideal which…

Commutative Algebra · Mathematics 2011-05-18 Seyed Hamid Hassanzadeh

We determine a term order on the monomials in the variables $\varx{i}{j}$, $1 \leq i < j \leq n$, such that corresponding initial ideal of the ideal of Pfaffians of degree $r$ of a generic $n$ by $n$ skew-symmetric matrix is the…

Combinatorics · Mathematics 2007-05-23 J. Jonsson , V. Welker

We show that a finite regular cell complex with the intersection property is a Cohen-Macaulay space iff the top enriched cohomology module is the only nonvanishing one. We prove a comprehensive generalization of Balinski's theorem on convex…

Combinatorics · Mathematics 2011-12-14 Gunnar Floystad

We call a simplicial complex algebraically rigid if its Stanley-Reisner ring admits no nontrivial infinitesimal deformations, and call it inseparable if does not allow any deformation to other simplicial complexes. Algebraically rigid…

Commutative Algebra · Mathematics 2021-04-07 Klaus Altmann , Mina Bigdeli , Juergen Herzog , Dancheng Lu