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Let $G$ be a simple graph on the vertex set $\{1,\ldots,n\}$ with $m$ edges. An algebraic object attached to $G$ is the ideal $P_{G}$ generated by diagonal 2-minors of an $n \times n$ matrix of variables. In this paper we prove that if $G$…

Commutative Algebra · Mathematics 2016-07-26 Anargyros Katsabekis

Associated to any hypergraph is a toric ideal encoding the algebraic relations among its edges. We study these ideals and the combinatorics of their minimal generators, and derive general degree bounds for both uniform and non-uniform…

Commutative Algebra · Mathematics 2012-12-24 Elizabeth Gross , Sonja Petrović

In this paper we show that if for an integer matrix A the universal Gr\"obner basis of the associated toric ideal \Ideal_A coincides with the Graver basis of A, then the Gr\"obner complexity u(A) and the Graver complexity g(A) of its higher…

Commutative Algebra · Mathematics 2007-09-03 Raymond Hemmecke , Kristen A. Nairn

Statistical models of evolution are algebraic varieties in the space of joint probability distributions on the leaf colorations of a phylogenetic tree. The phylogenetic invariants of a model are the polynomials which vanish on the variety.…

Populations and Evolution · Quantitative Biology 2007-05-23 Bernd Sturmfels , Seth Sullivant

In this paper, we study toric ideals generated by circuits. For toric ideals which have squarefree quadratic initial ideals, a sufficient condition to be generated by circuits is given. In particular, squarefree Veronese subrings, the…

Commutative Algebra · Mathematics 2014-05-15 Hidefumi Ohsugi , Takayuki Hibi

Unconditional polytopes are convex polytopes that are symmetric with respect to all coordinate hyperplanes and arise naturally from anti-blocking polytopes by reflection. This paper investigates algebraic relations between an anti-blocking…

Combinatorics · Mathematics 2026-05-20 Kenta Mori , Ryo Motomura , Hidefumi Ohsugi , Akiyoshi Tsuchiya

A complete determination of the prime ideals invariant under winding automorphisms in the generic 3 by 3 quantum matrix algebra is obtained. Explicit generating sets consisting of quantum minors are given for all of these primes, thus…

Quantum Algebra · Mathematics 2007-05-23 K. R. Goodearl , T. H. Lenagan

A cosmological polytope is defined for a given Feynman diagram, and its canonical form may be used to compute the contribution of the Feynman diagram to the wavefunction of certain cosmological models. Given a subdivision of a polytope, its…

Combinatorics · Mathematics 2023-03-13 Martina Juhnke-Kubitzke , Liam Solus , Lorenzo Venturello

Toric topology assigns to each $n$-dimensional combinatorial simple convex polytope $P$ with $m$ facets an $(m+n)$-dimensional moment-angle manifold $\mathcal{Z}_P$ with an action of a compact torus $T^m$ such that $\mathcal{Z}_P/T^m$ is a…

Algebraic Topology · Mathematics 2020-12-29 Nikolai Erokhovets

This dissertation investigates the geometric combinatorics of convex polytopes and connections to the behavior of the simplex method for linear programming. We focus our attention on transportation polytopes, which are sets of all tables of…

Combinatorics · Mathematics 2010-06-15 Edward D. Kim

We classify and construct all line graphs that are $3$-polytopes (planar and $3$-connected). Apart from a few special cases, they are all obtained starting from the medial graphs of cubic (i.e., $3$-regular) $3$-polytopes, by applying two…

Combinatorics · Mathematics 2024-04-12 Phoebe Hollowbread-Smith , Riccardo W. Maffucci

Quaternionic polynomials are generated by quaternionic variables and the quaternionic product. This paper proposes the generating ideal of quaternionic polynomials in tensor algebra, finds the Groebner base of the ideal in the case of pure…

Rings and Algebras · Mathematics 2013-01-24 Hongbo Li , Lei Huang , Yue Liu

We investigate the structure of ideals generated by binomials (polynomials with at most two terms) and the schemes and varieties associated to them. The class of binomial ideals contains many classical examples from algebraic geometry, and…

alg-geom · Mathematics 2008-02-03 David Eisenbud , Bernd Sturmfels

In this paper we introduce a new and large family of configurations whose toric ideals possess quadratic Groebner bases. As an application, a generalization of algebras of Segre-Veronese type will be studied.

Commutative Algebra · Mathematics 2008-09-23 Satoshi Aoki , Takayuki Hibi , Hidefumi Ohsugi , Akimichi Takemura

Let I be the toric ideal of a homogeneous normal configuration. We prove that I is generated by circuits if and only if each unbalanced circuit of I has a "connector" which is a linear combination of circuits with a square-free term. In…

Commutative Algebra · Mathematics 2012-07-27 Jose Martinez-Bernal , Rafael H. Villarreal

A graph-theoretic method, simpler than existing ones, is used to characterize the minimal set of monomial generators for the integral closure of any algebra of polynomials generated by quadratic monomials. The toric ideal of relations…

Commutative Algebra · Mathematics 2010-01-31 Peter M. Johnson

The slack ideal of a polytope is a saturated determinantal ideal that gives rise to a new model for the realization space of the polytope. The simplest slack ideals are toric and have connections to projectively unique polytopes. We prove…

Combinatorics · Mathematics 2019-08-09 João Gouveia , Antonio Macchia , Rekha R. Thomas , Amy Wiebe

Tropical ideals are a class of ideals in the tropical polynomial semiring that combinatorially abstracts the possible collections of supports of all polynomials in an ideal over a field. We study zero-dimensional tropical ideals I with…

Combinatorics · Mathematics 2021-02-23 Nicholas Anderson , Felipe Rincón

For an arbitrary field K, let I be an ideal in the ring K[[x,y]] expressible as a polynomial in either the pair of ideals (x, y^4) and (x,y) or the pair (x,y^3) and (x^2, y). Let G be the group of automorphisms of K[[x,y]] sending the ideal…

Algebraic Geometry · Mathematics 2007-05-23 Heather Russell

In 1980, White conjectured that the toric ideal associated to a matroid is generated by binomials corresponding to a symmetric exchange. In this paper, we prove that classes of matroids for which the toric ideal is generated by quadrics and…

Combinatorics · Mathematics 2019-07-22 Kazuki Shibata