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Related papers: On the gamma-vector of symmetric edge polytopes

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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

The symmetric edge polytope (SEP) of a (finite, undirected) graph is a centrally symmetric lattice polytope whose vertices are defined by the edges of the graph. SEPs have been studied extensively in the past twenty years. Recently,…

Combinatorics · Mathematics 2026-05-19 Robert Davis , Akihiro Higashitani , Hidefumi Ohsugi

Symmetric edge polytopes are lattice polytopes associated with finite simple graphs that are of interest in both theory and applications. We investigate the facet structure of symmetric edge polytopes for various models of random graphs.…

Combinatorics · Mathematics 2024-02-14 Benjamin Braun , Kaitlin Bruegge , Matthew Kahle

In [7], Higashitani, Kummer, and Micha{\l}ek pose a conjecture about the symmetric edge polytopes of complete multipartite graphs and confirm it for a number of families in the bipartite case. We confirm that conjecture for a number of new…

Combinatorics · Mathematics 2024-04-03 Max Kölbl

From the paper of the first author it follows that upper and lower bounds for $\gamma$-vector of a simple polytope imply the bounds for its $g$-,$h$- and $f$-vectors. In the paper of the second author it was obtained unimprovable upper and…

Combinatorics · Mathematics 2010-05-18 Victor M. Buchstaber , Vadim Volodin

Amalgamation in the totally non-negative part of positroid varieties is equivalent to gluing copies of $Gr^{TP}(1,3)$ and $Gr^{TP}(2,3)$. Lam has proposed to represent amalgamation in positroid varieties by equivalence classes of relations…

Combinatorics · Mathematics 2022-06-06 Simonetta Abenda , Petr G. Grinevich

We investigate symmetric edge polytopes generated by Erd\H{o}s--R\'enyi random graphs in a high-dimensional regime. These objects provide a natural and largely unexplored model of random lattice polytopes, in which geometric properties are…

Combinatorics · Mathematics 2026-03-12 Torben Donzelmann , Martina Juhnke , Benedikt Rednoß , Christoph Thäle

The $\gamma$-vector is an important enumerative invariant of a flag simplicial homology sphere. It has been conjectured by Gal that this vector is nonnegative for every such sphere $\Delta$ and by Reiner, Postnikov and Williams that it…

Combinatorics · Mathematics 2012-06-07 Christos A. Athanasiadis

Graph polytopes arising from vertex-weighted graphs were first introduced by B\'ona, Ju, and Yoshida. We prove a conjecture stating that for any simple connected graph, the numerator polynomial of the Ehrhart series of its graph polytope is…

Combinatorics · Mathematics 2026-04-13 Feihu Liu

The symmetric edge polytope of a simple graph is a lattice polytope defined as the convex hull of a subset of the type A roots corresponding to the edges of the graph. In this article we prove a sharp lower bound for the number of edges of…

Combinatorics · Mathematics 2025-12-19 Giulia Codenotti , Roberto Riccardi , Lorenzo Venturello

Haemers conjectures that almost all graphs are determined by their spectra. Suppose $G \sim \mathcal{G}(n, p)$ is a random graph with each edge chosen independently with probability $p$ with $0 < p < 1$. Then $$\Pr(G \text{ is not…

Combinatorics · Mathematics 2025-09-09 Wei Wang , Da Zhao

Symmetric edge polytopes of graphs are important object in Ehrhart theory,and have an application to Kuramoto models. In the present paper, we study the upper and lower bounds for the number of facets of symmetric edge polytopes of…

Combinatorics · Mathematics 2025-05-01 Aki Mori , Kenta Mori , Hidefumi Ohsugi

Bollob\'{a}s and Nikiforov (J. Combin. Theory Ser. B. 97 (2007) 859-865) conjectured that for a graph $G$ with $e(G)$ edges and the clique number $\omega(G)$, then $ \lambda_{1}^{2}+\lambda_{2}^{2}\leq…

Combinatorics · Mathematics 2025-01-14 Chunmeng Liu , Changjiang Bu

We show that for a sequence of random graphs Brouwer's conjecture holds true with probability tending to one as the number of vertices tends to infinity. Surprisingly, it was found that a similar statement holds true for weighted graphs…

Combinatorics · Mathematics 2019-06-14 Israel Rocha

We consider an inhomogeneous Erd\H{o}s-R\'enyi random graph ensemble with exponentially decaying random disconnection probabilities determined by an i.i.d. field of variables with heavy tails and infinite mean associated to the vertices of…

Probability · Mathematics 2026-04-01 Luca Avena , Diego Garlaschelli , Rajat Subhra Hazra , Margherita Lalli

The interior angle vector ($\widehat{\alpha}$-vector) of a polytope is a metric analogue of the $f$-vector in which faces are weighted by their solid angle. For simplicial polytopes, Dehn-Sommerville-type relations on the…

Combinatorics · Mathematics 2020-07-15 Sebastian Manecke

As a first step towards a conjecture of Kahle and Newman, we prove that if $T_n$ is a random $2$-dimensional determinantal hypertree on $n$ vertices, then \[\frac{\dim H_1(T_n,\mathbb{F}_2)}{n^2}\] converges to zero in probability.…

Combinatorics · Mathematics 2025-01-28 András Mészáros

The celebrated Mantel's theorem states that any triangle-free graph on $n$ vertices contains at most $\left\lfloor n^2/4\right\rfloor$ edges. It is natural to ask how many triangles must exist in a graph with more than $\left\lfloor…

Combinatorics · Mathematics 2026-02-27 Yuhang Bai , Gyula O. H. Katona , Zixuan Yang

We investigate the problem of detecting correlation between two Erd\H{o}s-R\'enyi graphs $G(n,p)$, formulated as a hypothesis testing problem: under the null hypothesis, the two graphs are independent, while under the alternative…

Social and Information Networks · Computer Science 2026-03-18 Dong Huang , Pengkun Yang

We study cosmological polytopes induced by Erd\H{o}s--R\'enyi random graphs in a high-dimensional regime. These graph-based lattice polytopes form a natural model of random lattice polytopes in which geometric features are determined by the…

Combinatorics · Mathematics 2026-05-25 Torben Donzelmann , Martina Juhnke , Benedikt Rednoß , Christoph Thäle
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