English
Related papers

Related papers: Graphings and Unimodularity

200 papers

In this article we introduce the notion of weak harmonic labeling of a graph, a generalization of the concept of harmonic labeling defined recently by Benjamini et al. that allows extension to finite graphs and graphs with leaves. We…

Combinatorics · Mathematics 2020-12-01 Pablo Leandro Bonucci , Nicolás Ariel Capitelli

Inspired by the notion of action convergence in graph limit theory, we introduce a measure-theoretic representation of matrices, and we use it to define a new notion of pseudo-metric on the space of matrices. Moreover, we show that such…

Combinatorics · Mathematics 2023-01-05 Raffaella Mulas , Giulio Zucal

A graph is a mathematical object consisting of a set of vertices and a set of edges connecting vertices. Graphs can be drawn on paper in various ways, but until recently all published methods of drawing graphs have had undesirable…

Human-Computer Interaction · Computer Science 2014-05-22 Bob Blakley , G R Blakley , Sean M Blakley

A typical result in graph theory says that a graph $G$, satisfying certain conditions, has some property $\cal P$. Once such a theorem is established, it is natural to ask how strongly $G$ satisfies $\cal P$. Can one strengthen the result…

Combinatorics · Mathematics 2016-11-14 Benny Sudakov

A graph is strongly perfect if every induced subgraph H has a stable set that meets every nonempty maximal clique of H. The characterization of strongly perfect graphs by a set of forbidden induced subgraphs is not known. Here we provide…

Combinatorics · Mathematics 2020-03-05 Maria Chudnovsky , Cemil Dibek , Paul Seymour

Graph embeddings deal with injective maps from a given simple, undirected graph $G=(V,E)$ into a metric space, such as $\mathbb{R}^n$ with the Euclidean metric. This concept is widely studied in computer science, see \cite{ge1}, but also…

Combinatorics · Mathematics 2022-05-04 Dominic van der Zypen

In this paper we consider aspects of geometric observability for hypergraphs, extending our earlier work from the uniform to the nonuniform case. Hypergraphs, a generalization of graphs, allow hyperedges to connect multiple nodes and…

Dynamical Systems · Mathematics 2024-04-12 Joshua Pickard , Cooper Stansbury , Amit Surana , Indika Rajapakse , Anthony Bloch

We observe that the nonstandard finite cardinality of a definable set in a strongly minimal pseudofinite structure D is a polynomial over the integers in the nonstandard finite cardinality of D. We conclude that D is unimodular, hence also…

Logic · Mathematics 2014-11-25 Anand Pillay

An intense activity is nowadays devoted to the definition of models capturing the properties of complex networks. Among the most promising approaches, it has been proposed to model these graphs via their clique incidence bipartite graphs.…

Discrete Mathematics · Computer Science 2021-03-09 Matthieu Latapy , Thi Ha Duong Phan , Christophe Crespelle , Thanh Qui Nguyen

In 1985, Golumbic and Scheinerman established an equivalence between comparability graphs and containment graphs, graphs whose vertices represent sets, with edges indicating set containment. A few years earlier, McMorris and Zaslavsky…

Combinatorics · Mathematics 2025-03-31 Ketai Chen , Jared DeLeo , Owen Henderschedt

We investigate families of graphs and graphons (graph limits) that are defined by a finite number of prescribed subgraph densities. Our main focus is the case when the family contains only one element, i.e., a unique structure is forced by…

Combinatorics · Mathematics 2013-08-23 Laszlo Lovasz , Balazs Szegedy

We derive representation theorems for exchangeable distributions on finite and infinite graphs using elementary arguments based on geometric and graph-theoretic concepts. Our results elucidate some of the key differences, and their…

Statistics Theory · Mathematics 2018-09-18 Steffen L. Lauritzen , Alessandro Rinaldo , Kayvan Sadeghi

In this paper we investigate invertibility of graphs with a unique perfect matching, i.e. graphs having a unique 1-factor. We recall the new notion of the so-called negatively invertible graphs investigated by the authors in the recent…

Combinatorics · Mathematics 2016-12-08 Sona Pavlikova , Daniel Sevcovic

A graph is regularizable if it is possible to assign weights to its edges so that all nodes have the same degree. Weights can be positive, nonnegative or arbitrary as soon as the regularization degree is not null. Positive and nonnegative…

Social and Information Networks · Computer Science 2017-07-03 Massimo Franceschet , Enrico Bozzo

We consider a variant of so called power-law random graph. A sequence of expected degrees corresponds to a power-law degree distribution with finite mean and infinite variance. In previous works the asymptotic picture with number of nodes…

Probability · Mathematics 2007-12-12 Hannu Reittu , Ilkka Norros

Let $G$ be a group. The \emph{power graph} of $G$ is a graph with the vertex set $G$, having an edge between two elements whenever one is a power of the other. We characterize nilpotent groups whose power graphs have finite independence…

Combinatorics · Mathematics 2019-05-31 Ghodratollah Aalipour , Saieed Akbari , Peter J. Cameron , Reza Nikandish , Farzad Shaveisi

We show that, given an infinite cardinal $\mu$, a graph has colouring number at most $\mu$ if and only if it contains neither of two types of subgraph. We also show that every graph with infinite colouring number has a well-ordering of its…

Combinatorics · Mathematics 2018-07-05 Nathan Bowler , Johannes Carmesin , Péter Komjáth , Christian Reiher

Barbieri recently showed that the finite graphs realising any given finite automorphism group have unbounded genus, answering a question of Cornwell et al. In this note we give a short proof of a stronger result: they have unbounded clique…

Combinatorics · Mathematics 2025-01-20 John Haslegrave

We study characteristics which might distinguish two-graphs by introducing different numerical measures on the collection of graphs on $n$ vertices. Two conjectures are stated, one using these numerical measures and the other using the deck…

Combinatorics · Mathematics 2008-10-20 David M. Duncan , Thomas R. Hoffman , James P. Solazzo

A graph is called 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we establish a local property of 1-planar graphs which describes the structure in the neighborhood of small…

Discrete Mathematics · Computer Science 2011-01-04 Xin Zhang , Guizhen Liu , Jian-Liang Wu