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Related papers: Roots of Ehrhart polynomials arising from graphs

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Matroids give rise to several natural constructions of polytopes. Inspired by this, we examine polytopes that arise from the signed circuits of an oriented matroid. We give the dimensions of these polytopes arising from graphical oriented…

Combinatorics · Mathematics 2025-01-03 Laura Escobar , Jodi McWhirter

We determine lattice polytopes of smallest volume with a given number of interior lattice points. We show that the Ehrhart polynomials of those with one interior lattice point have largest roots with norm of order n^2, where n is the…

Metric Geometry · Mathematics 2007-05-23 Christian Bey , Martin Henk , Joerg M. Wills

It is shown that, for each $d \geq 4$, there exists an integral convex polytope $\mathcal{P}$ of dimension $d$ such that each of the coefficients of $n, n^{2}, \ldots, n^{d-2}$ of its Ehrhart polynomial $i(\mathcal{P},n)$ is negative.

Combinatorics · Mathematics 2014-01-03 Takayuki Hibi , Akihiro Higashitani , Akiyoshi Tsuchiya , Koutarou Yoshida

In earlier work in collaboration with Pavel Galashin and Thomas McConville we introduced a version of chip-firing for root systems. Our investigation of root system chip-firing led us to define certain polynomials analogous to Ehrhart…

Combinatorics · Mathematics 2019-12-24 Sam Hopkins , Alexander Postnikov

The cosmological polytope of a graph $G$ was recently introduced to give a geometric approach to the computation of wavefunctions for cosmological models with associated Feynman diagram $G$. Basic results in the theory of positive…

Combinatorics · Mathematics 2025-01-09 Justus Bruckamp , Lina Goltermann , Martina Juhnke , Erik Landin , Liam Solus

Ehrhart discovered that the function that counts the number of lattice points in dilations of an integral polytope is a polynomial. We call the coefficients of this polynomial Ehrhart coefficients, and say a polytope is Ehrhart positive if…

Combinatorics · Mathematics 2018-09-05 Fu Liu

We investigate the Ehrhart polynomial for the class of 0-symmetric convex lattice polytopes in Euclidean $n$-space $\mathbb{R}^n$. It turns out that the roots of the Ehrhart polynomial and Minkowski's successive minima are closely related…

Metric Geometry · Mathematics 2011-10-20 Martin Henk , Achill Schuermann , Joerg M. Wills

A graph whose nodes have degree 1 or 3 is called a $\{1,3\}$-graph. Liu and Osserman associated a polytope to each $\{1,3\}$-graph and studied the Ehrhart quasi-polynomials of these polytopes. They showed that the vertices of these…

Combinatorics · Mathematics 2021-04-23 Cristina G. Fernandes , José C. de Pina , Jorge L. Ramírez Alfonsín , Sinai Robins

Reflexive polytopes which have the integer decomposition property are of interest. Recently, some large classes of reflexive polytopes with integer decomposition property coming from the order polytopes and the chain polytopes of finite…

Combinatorics · Mathematics 2020-09-08 Takayuki Hibi , Akiyoshi Tsuchiya

We investigate arithmetic, geometric and combinatorial properties of symmetric edge polytopes. We give a complete combinatorial description of their facets. By combining Gr\"obner basis techniques, half-open decompositions and methods for…

Combinatorics · Mathematics 2019-05-15 Akihiro Higashitani , Katharina Jochemko , Mateusz Michałek

We study the extended root polytope associated to a directed graph. We show that under the operations of deletion and contraction of an edge of the graph, none of the coefficients of the $h^*$-polynomial of the associated extended root…

Combinatorics · Mathematics 2025-01-10 Tamás Kálmán , Lilla Tóthmérész

A $0/1$-polytope in $\mathbb{R}^n$ is the convex hull of a subset of $\{0,1\}^n$. The graph of a polytope $P$ is the graph whose vertices are the zero-dimensional faces of $P$ and whose edges are the one-dimensional faces of $P$. A…

Combinatorics · Mathematics 2025-09-15 Asaf Ferber , Michael Krivelevich , Marcelo Sales , Wojciech Samotij

In this paper we calculate the Ehrhart's polynomial associated with a 2-dimensional regular polytope (i.e. equilateral triangles) in $\mathbb Z^3$. The polynomial takes a relatively simple form in terms of the coordinates of the vertices of…

Number Theory · Mathematics 2011-07-12 Eugen J. Ionascu

Reflexive polytopes form one of the distinguished classes of lattice polytopes. Especially reflexive polytopes which possess the integer decomposition property are of interest. In the present paper, by virtue of the algebraic technique on…

Combinatorics · Mathematics 2020-09-08 Takayuki Hibi , Akiyoshi Tsuchiya

Let $\mathcal{P} \subseteq \mathbb{R}^{n}$ be a polytope whose vertices have rational coordinates. By a seminal result of E. Ehrhart, the number of integer lattice points in the $k$th dilate of $\mathcal{P}$ ($k$ a positive integer) is a…

Combinatorics · Mathematics 2026-02-04 Tyrrell B. McAllister , Hélène O. Rochais

Over a decade ago De Loera, Haws and K\"oppe conjectured that Ehrhart polynomials of matroid polytopes have only positive coefficients and that the coefficients of the corresponding $h^*$-polynomials form a unimodal sequence. The first of…

Combinatorics · Mathematics 2022-08-05 Luis Ferroni , Katharina Jochemko , Benjamin Schröter

The fractional stable set polytope ${\rm FRAC}(G)$ of a simple graph $G$ with $d$ vertices is a rational polytope that is the set of nonnegative vectors $(x_1,\ldots,x_d)$ satisfying $x_i+x_j\le 1$ for every edge $(i,j)$ of $G$. In this…

Combinatorics · Mathematics 2018-09-03 Ginji Hamano , Takayuki Hibi , Hidefumi Ohsugi

The magic positivity of Ehrhart polynomials is a useful tool for proving the real-rootedness of the $h^\ast$-polynomials. In this paper, we provide a new class of reflexive polytopes whose Ehrhart polynomials are magic positive. First, we…

Combinatorics · Mathematics 2025-07-03 Masato Konoike

We investigate properties of Ehrhart polynomials for matroid polytopes, independence matroid polytopes, and polymatroids. In the first half of the paper we prove that for fixed rank their Ehrhart polynomials are computable in polynomial…

Combinatorics · Mathematics 2017-01-03 Jesús A. De Loera , David C. Haws , Matthias Köppe

To directed graphs with unique sink and source we associate a noncommutative associative alsgebra and a polynomial over this algebra. Edges of the graph correspond to pseudo-roots of the polynomial. We give a sufficient condition when…

Quantum Algebra · Mathematics 2009-11-11 Israel Gelfand , Sergei Gelfand , Vladimir Retakh , Robert Lee Wilson