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Related papers: Ends of digraphs I: basic theory

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We discuss topological versions of the closed graph theorem, where continuity is inferred from near continuity in tandem with suitable conditions on source or target spaces. We seek internal characterizations of spaces satisfying a closed…

General Topology · Mathematics 2024-04-05 Dominikus Noll

The law of a finite graph is a probability measure induced by the orbits of the graph under its automorphism group. Every law satisfies the intrinsic mass transport principle, which is also known as unimodularity. We discuss the convergence…

Combinatorics · Mathematics 2011-03-30 Igor Artemenko

A problem by Diestel is to extend algebraic flow theory of finite graphs to infinite graphs with ends. In order to pursue this problem, we define an A-flow and non-elusive H-flow for arbitrary graphs and for abelian topological Hausdorff…

Combinatorics · Mathematics 2016-12-26 Babak Miraftab , Javad Moghadamzadeh

We consider the problem of placing arrow heads in directed graph drawings without them overlapping other drawn objects. This gives drawings where edge directions can be deduced unambiguously. We show hardness of the problem, present exact…

Data Structures and Algorithms · Computer Science 2016-08-31 Carla Binucci , Markus Chimani , Walter Didimo , Giuseppe Liotta , Fabrizio Montecchiani

In finite graphs, finite-order tangles offer an abstract description of highly connected substructures. In infinite graphs, infinite-order tangles compactify the graphs in the same way the ends compactify connected locally finite graphs.…

Combinatorics · Mathematics 2019-08-28 Jan Kurkofka

The concept of coreflexive set is introduced to study the structure of digraphs. New characterizations of line digraphs and nth-order line digraphs are given. Coreflexive sets also lead to another natural way of forming an intersection…

Combinatorics · Mathematics 2007-05-23 Xinming Liu , Douglas B. West

We introduce and study the Separation Problem for infinite graphs, which involves determining whether a connected graph splits into at least two infinite connected components after the removal of a given finite set of edges. We prove that…

Logic · Mathematics 2026-02-11 Nicanor Carrasco-Vargas , Valentino Delle Rose , Cristóbal Rojas

We define cofinite graphs and cofinite groupoids in a unified way that extends the notion of cofinite groups introduced by Hartley. The common underlying structure of all these objects is that they are directed graphs endowed with a certain…

Group Theory · Mathematics 2016-10-31 Amrita Acharyya , Jon M. Corson , Bikash Das

Recently, bidirected graphs have received increasing attention from the graph theory community with both structural and algorithmic results. Bidirected graphs are a generalization of directed graphs, consisting of an undirected graph…

Combinatorics · Mathematics 2025-12-16 Tara Abrishami , Nathan Bowler , Attila Joó , Florian Reich , Qiuzhenyu Tao

Given an underlying undirected simple graph, we consider the set of all acyclic orientations of its edges. Each of these orientations induces a partial order on the vertices of our graph and, therefore, we can count the number of linear…

Combinatorics · Mathematics 2015-02-17 Benjamin Iriarte Giraldo

Thomas proved that every undirected graph admits a linked tree decomposition of width equal to its treewidth. In this paper, we generalize Thomas's theorem to digraphs. We prove that every digraph G admits a linked directed path…

Combinatorics · Mathematics 2014-04-25 Shiva Kintali

While finite graphs have tree-decompositions that efficiently distinguish all their tangles, locally finite graphs with thick ends need not have such tree-decompositions. We show that every locally finite graph without thick ends admits…

Combinatorics · Mathematics 2024-03-25 Raphael W. Jacobs , Paul Knappe

We analyze the distribution of the distance between two nodes, sampled uniformly at random, in digraphs generated via the directed configuration model, in the supercritical regime. Under the assumption that the covariance between the…

Probability · Mathematics 2017-04-24 Pim van der Hoorn , Mariana Olvera-Cravioto

The theory of convergent graph sequences has been worked out in two extreme cases, dense graphs and bounded degree graphs. One can define convergence in terms of counting homomorphisms from fixed graphs into members of the sequence…

Combinatorics · Mathematics 2010-02-02 Christian Borgs , Jennifer Chayes , Jeff Kahn , László Lovász

Strict outerconfluent drawing is a style of graph drawing in which vertices are drawn on the boundary of a disk, adjacencies are indicated by the existence of smooth curves through a system of tracks within the disk, and no two adjacent…

Combinatorics · Mathematics 2024-12-11 David Eppstein

In this paper we offer a metric similar to graph edit distance which measures the distance between two (possibly infinite)weighted graphs with finite norm (we define the norm of a graph as the sum of absolute values of its edges). The main…

Metric Geometry · Mathematics 2009-06-16 Hamed Daneshpajouh , Hamid Reza Daneshpajouh , Farzad Didehvar

We generalise structure tree theory, which is based on removing finitely many edges, to removing finitely many vertices. This gives a significant generalization of Tutte's tree decomposition of 2-connected graphs into 3-connected blocks.…

Group Theory · Mathematics 2015-01-05 M. J. Dunwoody , B. Krön

We extend the concept of the law of a finite graph to graphings, which are, in general, infinite graphs whose vertices are equipped with the structure of a probability space. By doing this, we obtain a vast array of new unimodular measures.…

Combinatorics · Mathematics 2012-03-13 Igor Artemenko

It is well-known that in finite graphs, large complete minors/topological minors can be forced by assuming a large average degree. Our aim is to extend this fact to infinite graphs. For this, we generalise the notion of the relative end…

Combinatorics · Mathematics 2011-02-03 Maya Stein , José Zamora

We introduce and develop a theory of limits for sequences of sparse graphs based on $L^p$ graphons, which generalizes both the existing $L^\infty$ theory of dense graph limits and its extension by Bollob\'as and Riordan to sparse graphs…

Combinatorics · Mathematics 2019-08-19 Christian Borgs , Jennifer T. Chayes , Henry Cohn , Yufei Zhao