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We prove distance bounds for graphs possessing positive Bakry-\'Emery curvature apart from an exceptional set, where the curvature is allowed to be non-positive. If the set of non-positively curved vertices is finite, then the graph admits…

Differential Geometry · Mathematics 2019-03-26 Shiping Liu , Florentin Münch , Norbert Peyerimhoff , Christian Rose

One deals with r-regular bipartite graphs with 2n vertices. In a previous paper Butera, Pernici, and the author have introduced a quantity d(i), a function of the number of i-matchings, and conjectured that as n goes to infinity the…

Combinatorics · Mathematics 2019-09-10 Paul Federbush

Let $g$ be a bounded symmetric measurable nonnegative function on $[0,1]^2$, and $\left\lVert g \right\rVert = \int_{[0,1]^2} g(x,y) dx dy$. For a graph $G$ with vertices $\{v_1,v_2,\ldots,v_n\}$ and edge set $E(G)$, we define \[ t(G,g) \;…

Combinatorics · Mathematics 2021-02-15 Alexander Sidorenko

The Burning Number Conjecture, that a graph on $n$ vertices can be burned in at most $\lceil \sqrt{n} \ \rceil$ rounds, has been of central interest for the past several years. Much of the literature toward its resolution focuses on two…

Combinatorics · Mathematics 2021-11-03 Mohamed Omar , Vibha Rohilla

Let G = (V, p, $\mu$) be a (finite or infinite) weighted graph with bounded geometry. Assuming that G satisfies the classical curvaturedimension condition of Bakry-Emery CD(K, n) with K $\ge$ 0 (for the usual Laplacian), we prove that the…

Differential Geometry · Mathematics 2025-07-28 Emmanuel Russ , Hervé Pajot

In this article we prove that antitrees with suitable growth properties are examples of infinite graphs exhibiting strictly positive curvature in various contexts: in the normalized and non-normalized Bakry-\'Emery setting as well in the…

Combinatorics · Mathematics 2018-01-30 David Cushing , Shiping Liu , Florentin Münch , Norbert Peyerimhoff

The paper revisits recent counterintuitive results on divergence of heat conduction coefficient in two-dimensional lattices. It was reported that in certain lattices with on-site potential, for which one-dimensional chain has convergent…

Statistical Mechanics · Physics 2016-03-23 A. V. Savin , V. Zolotarevskiy , O. V. Gendelman

A graph property is elusive (or evasive) if any algorithm testing it by asking questions of the form ''Is there an edge between vertices x and y?'' must, in the worst case, examine all pairs of vertices. Elusiveness for infinite vertex sets…

Combinatorics · Mathematics 2025-10-22 Márton Elekes , Tamás Kátay , Anett Kocsis

Graph burning is a discrete time process which can be used to model the spread of social contagion. One is initially given a graph of unburned vertices. At each round (time step), one vertex is burned; unburned vertices with at least one…

Combinatorics · Mathematics 2023-12-25 Yukihiro Murakami

In this paper, we prove the equivalent of ultracontractive bound of heat semigroup or the uniform upper bound of the heat kernel with the Nash inequality, Log-Sobolev inequalities on graphs. We also show that under the assumption of volume…

Differential Geometry · Mathematics 2015-02-09 Yong Lin , Shuang Liu , Hongye Song

Graph burning models the spread of information or contagion in a graph. At each time step, two events occur: neighbours of already burned vertices become burned, and a new vertex is chosen to be burned. The big conjecture is known as the…

Combinatorics · Mathematics 2024-12-18 Danielle Cox , M. E. Messinger , Kerry Ojakian

One deals with r-regular bipartite graphs with 2n vertices. In a previous paper Butera, Pernici, and the author have introduced a quantity d(i), a function of the number of i-matchings, and conjectured that as n goes to infinity the…

Combinatorics · Mathematics 2022-05-10 Paul Federbush

Let $J$ be the L\'evy density of a symmetric L\'evy process in $\mathbb{R}^d$ with its L\'evy exponent satisfying a weak lower scaling condition at infinity. Consider the non-symmetric and non-local operator $$ {\mathcal L}^{\kappa}f(x):=…

Probability · Mathematics 2017-03-14 Panki Kim , Renming Song , Zoran Vondraček

We construct a connected graph H such that (1) \chi(H) = \omega; (2) K_\omega, the complete graph on \omega points, is not a minor of H. Therefore Hadwiger's conjecture does not hold for graphs with infinite coloring number.

Combinatorics · Mathematics 2012-12-14 Dominic van der Zypen

For a graph $G$, its energy $\mathcal{E}(G)$ is the sum of absolute values of the eigenvalues of its adjacency matrix, the matching number $\mu(G)$ is the number of edges in a maximum matching of $G$, while $\Delta$ is the maximum vertex…

Combinatorics · Mathematics 2021-12-01 Đorđe Stevanović , Ivan Damnjanović , Dragan Stevanović

In this paper, we present a minimal counterexample to a conjecture of Perles that answers a question of Haase and Ziegler. The example is a simple 4-polytope that has an induced 3-connected 3-regular subgraph, whose graph complement is…

Combinatorics · Mathematics 2018-09-10 Joseph Doolittle

We clarify the correspondence between the two approaches to quantum graphs: via quantum adjacency matrices and via quantum relations. We show how the choice of a (possibly non-tracial) weight manifests itself on the quantum relation side…

Operator Algebras · Mathematics 2024-12-11 Mateusz Wasilewski

We consider circulant graphs having $p$ vertices, with $p$ prime. To any such graph we associate a certain number $k$, that we call type of the graph. We prove that for $p>>k$ the graph has no quantum symmetry, in the sense that the quantum…

Combinatorics · Mathematics 2007-08-30 Teodor Banica , Julien Bichon , Gaetan Chenevier

We consider two recent conjectures of Harrington, Henninger-Voss, Karhadkar, Robinson and Wong concerning relationships between the sum index, difference index and exclusive sum number of graphs. One conjecture posits an exact relationship…

Combinatorics · Mathematics 2023-03-22 John Haslegrave

Let $A \in \mathbb{R}^{n \times n}$ be the adjacency matrix of an Erd\H{o}s R\'enyi graph $G(n, d/n)$ for $d = \omega(1)$ and $d \leq 3\log(n)$. We show that as $n$ goes to infinity, with probability that goes to $1$, the adjacency matrix…

Combinatorics · Mathematics 2022-01-25 Margalit Glasgow