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Each linear code can be described by a code ideal given as the sum of a toric ideal and a non-prime ideal. In this way, several concepts from the theory of toric ideals can be translated into the setting of code ideals. It will be shown…

代数几何 · 数学 2014-01-14 Natalia Dück , Karl-Heinz Zimmermann

K3 polytopes appear in complements of tropical quartic surfaces. They are dual to regular unimodular central triangulations of reflexive polytopes in the fourth dilation of the standard tetrahedron. Exploring these combinatorial objects, we…

代数几何 · 数学 2019-07-17 Gabriele Balletti , Marta Panizzut , Bernd Sturmfels

In the present paper we show a link between bistochastic quantum channels and classical maps. The primary goal of this work is to analyse the multiplicative structure of the Birkhoff polytope of order 3 (the simplest non-trivial case). A…

数学物理 · 物理学 2018-11-26 Mateusz Snamina , Emil J. Zak

We describe a perturbation method that can be used to reduce the problem of finding the multivariate generating function (MGF) of a non-simple polytope to computing the MGF of simple polytopes. We then construct a perturbation that works…

组合数学 · 数学 2013-05-16 Fu Liu

This paper introduces the notion of an unravelled abstract regular polytope, and proves that $\SL_3(q) \rtimes <t>$, where $t$ is the transpose inverse automorphism of $\SL_3(q)$, possesses such polytopes for various congruences of $q$. A…

群论 · 数学 2021-05-06 Robert Nicolaides , Peter Rowley

In this paper we show that polyomino ideal of a simple polyomino coincides with the toric ideal of a weakly chordal bipartite graph and hence it has a quadratic Gr\"obner basis with respect to a suitable monomial order.

交换代数 · 数学 2015-01-26 Ayesha Asloob Qureshi , Takafumi Shibuta , Akihiro Shikama

This paper discusses properties of the graphs of 2-way and 3-way transportation polytopes, in particular, their possible numbers of vertices and their diameters. Our main results include a quadratic bound on the diameter of axial 3-way…

组合数学 · 数学 2010-07-19 Jesús A. De Loera , Edward D. Kim , Shmuel Onn , Francisco Santos

A $3$-dimensional polytope $P$ is $k$-equiprojective when the projection of $P$ along any line that is not parallel to a facet of $P$ is a polygon with $k$ vertices. In 1968, Geoffrey Shephard asked for a description of all equiprojective…

度量几何 · 数学 2025-10-06 Théophile Buffière , Lionel Pournin

We adapt the free monotone transport results of Guionnet and Shlyakhtenko to the type $\text{III}$ case. As a direct application, we obtain that the $q$-deformed Araki-Woods algebras are isomorphic (for sufficiently small $|q|$).

算子代数 · 数学 2015-06-17 Brent Nelson

In the present paper, we prove that the toric ideals of certain $s$-block diagonal matching fields have quadratic Gr\"obner bases. Thus, in particular, those are quadratically generated. By using this result, we provide a new family of…

交换代数 · 数学 2021-05-12 Akihiro Higashitani , Hidefumi Ohsugi

Let $I_G$ be the toric ideal of a graph $G$. We characterize in graph theoretical terms the primitive, the minimal, the indispensable and the fundamental binomials of the toric ideal $I_G$.

交换代数 · 数学 2010-02-11 Enrique Reyes , Christos Tatakis , Apostolos Thoma

Let $(X, A)$ be a polarized nonsingular toric 3-fold with not effective $A+K_X$. Then for any ample line bundle $L$ on $X$ the image of the embedding by the complete linear system of $L$ is an intersections of quadrics.

代数几何 · 数学 2020-04-10 Shoetsu Ogata

Let G be a finite graph on [n] = {1,2,3,...,n}, X a 2 times n matrix of indeterminates over a field K, and S = K[X] a polynomial ring over K. In this paper, we study about ideals I_G of S generated by 2-minors [i,j] of X which correspond to…

交换代数 · 数学 2009-11-16 Masahiro Ohtani

The lectures are devoted to a remarkable class of $3$-dimensional polytopes, which are mathematical models of the important object of quantum physics, quantum chemistry and nanotechnology -- fullerenes. The main goal is to show how results…

代数拓扑 · 数学 2016-09-13 Victor M. Buchstaber , Nickolai Erokhovets

Results of Koebe (1936), Schramm (1992), and Springborn (2005) yield realizations of $3$-polytopes with edges tangent to the unit sphere. Here we study the algebraic degrees of such realizations. This initiates the research on constrained…

组合数学 · 数学 2022-03-25 Mara Belotti , Michael Joswig , Marta Panizzut

We augment the list of finite universal locally toroidal regular polytopes of type {3,3,4,3,3} due to P.McMullen and E.Schulte, adding as well as removing entries. This disproves a related long-standing conjecture. Our new universal…

群论 · 数学 2017-07-05 Dmitrii V. Pasechnik

Every finite, self-dual, regular (or chiral) 4-polytope of type {3,q,3} has a trivalent 3-transitive (or 2-transitive) medial layer graph. Here, by dropping self-duality, we obtain a construction for semisymmetric trivalent graphs (which…

组合数学 · 数学 2007-05-23 Barry Monson , Tomaz Pisanski , Egon Schulte , Asia Ivic Weiss

This paper classifies all toric Fano 3-folds with terminal singularities. This is achieved by solving the equivalent combinatoric problem; that of finding, up to the action of GL(3,Z), all convex polytopes in Z^3 which contain the origin as…

代数几何 · 数学 2022-10-28 Alexander Kasprzyk

To any toric ideal $I_A$, encoded by an integer matrix $A$, we associate a matroid structure called {\em the bouquet graph} of $A$ and introduce another toric ideal called {\em the bouquet ideal} of $A$. We show how these objects capture…

交换代数 · 数学 2017-11-08 Sonja Petrović , Apostolos Thoma , Marius Vladoiu

The cut polytope of a graph is an important object in several fields, such as functional analysis, combinatorial optimization, and probability. For example, Sturmfels and Sullivant showed that the toric ideals of cut polytopes are useful in…

组合数学 · 数学 2020-04-13 Ryuichi Sakamoto