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Related papers: A subbase property for describing edge-end spaces

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In 1992, Diestel asked which topological spaces could be represented as the end space of some graph. In 2023, Pitz provided a solution to this question by giving a topological characterization of end spaces using a hereditarily complete…

General Topology · Mathematics 2026-04-21 Leandro Aurichi , Gustavo Boska , Davide Giacopello , Paulo Magalhães Júnior

Diestel and K\"uhn proved that the topological ends of an infinite graph are precisely its undominated graph ends, yielding a canonical embedding of the space of topological ends into the space of graph ends. For edge-ends, introduced by…

Combinatorics · Mathematics 2026-02-27 Leandro Aurichi , Paulo Magalhães Júnior , Guilherme Eduardo Pinto

We define a notion of (one-sided) edge shift spaces associated to ultragraphs. In the finite case our notion coincides with the edge shift space of a graph. In general, we show that our space is metrizable and has a countable basis of…

Operator Algebras · Mathematics 2017-05-19 Daniel Gonçalves , Danilo Royer

The notion of ends in an infinite graph $G$ might be modified if we consider them as equivalence classes of infinitely edge-connected rays, rather than equivalence classes of infinitely (vertex-)connected ones. This alternative definition…

Combinatorics · Mathematics 2026-04-16 Leandro Fiorini Aurichi , Paulo Magalhães Júnior , Lucas Real

We investigate path-, ray- and branch spaces of trees, certain topological spaces naturally associated with order theoretic trees, and provide topological characterisations for these spaces in terms of the existence of certain kinds of…

General Topology · Mathematics 2023-03-02 Max Pitz

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

End-spaces of infinite graphs naturally generalise the Freudenthal boundary and sit at the interface between graph theory, geometric group theory and topology. Our main result is that every end-space can topologically be represented by a…

Combinatorics · Mathematics 2024-09-02 Jan Kurkofka , Max Pitz

There are different definitions of ends in non-locally-finite graphs which are all equivalent in the locally finite case. We prove the compactness of the end-topology that is based on the principle of removing finite sets of vertices and…

Combinatorics · Mathematics 2009-10-31 B. Krön

Directions of graphs were originally introduced in the study of a cops-and-robbers kind of game, while the study of end spaces has been used to generalize classical graph-theoretical results to infinite graphs, such as Halin's…

Combinatorics · Mathematics 2025-10-21 Gustavo Boska , Matheus Duzi , Paulo Magalhães Júnior

In a series of three papers we develop an end space theory for digraphs. Here in the second paper we introduce the topological space $|D|$ formed by a digraph $D$ together with its ends and limit edges. We then characterise those digraphs…

Combinatorics · Mathematics 2020-09-08 Carl Bürger , Ruben Melcher

We show that the topological space of any infinite graph and its ends is normal. In particular, end spaces themselves are normal.

Combinatorics · Mathematics 2009-11-23 Philipp Sprüssel

Two of the natural topologies for infinite graphs with edge-ends are Etop and Itop. In this paper, we study and characterize them. We show that Itop can be constructed by inverse limits of inverse systems of graphs with finitely many…

General Topology · Mathematics 2016-12-20 Babak Miraftab

In a series of three papers we develop an end space theory for directed graphs. As for undirected graphs, the ends of a digraph are points at infinity to which its rays converge. Unlike for undirected graphs, some ends are joined by limit…

Combinatorics · Mathematics 2020-09-08 Carl Bürger , Ruben Melcher

In infinite graph theory, the notion of ends, first introduced by Freudenthal and Jung for locally finite graphs, plays an important role when generalizing statements from finite graphs to infinite ones. Nash-Willian's Tree-Packing Theorem…

Combinatorics · Mathematics 2024-04-30 Leandro Fiorini Aurichi , Lucas Real

We present a systematic investigation into how tree-decompositions of finite adhesion capture topological properties of the space formed by a graph together with its ends. As main results, we characterise when the ends of a graph can be…

Combinatorics · Mathematics 2023-05-17 Marcel Koloschin , Thilo Krill , Max Pitz

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

Without leaving finite mathematics and using finite topological spaces only, we give a definition of homeomorphisms of finite abstract simplicial complexes or finite graphs. Besides exploring the definition in various contexts, we add some…

Combinatorics · Mathematics 2023-01-10 Oliver Knill

We prove that the edge-end space of an infinite graph is metrizable if and only if it is first-countable. This strengthens a recent result by Aurichi, Magalhaes Jr.\ and Real (2024). Our central graph-theoretic tool is the use of tree-cut…

Combinatorics · Mathematics 2025-07-23 Max Pitz

This survey/expository article covers a variety of topics related to the "topology at infinity" of noncompact manifolds and complexes. In manifold topology and geometric group theory, the most important noncompact spaces are often…

Geometric Topology · Mathematics 2021-03-02 Craig R. Guilbault

In this paper we define a degree for ends of infinite digraphs. The well-definedness of our definition in particular resolves a problem by Zuther. Furthermore, we extend our notion of end degree to also respect, among others, the vertices…

Combinatorics · Mathematics 2025-02-03 Matthias Hamann , Karl Heuer
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