Pathographs and some (un)decidability results

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Carter, Daniel, Trotignon, Nicolas
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866915305505161216
author Carter, Daniel
Trotignon, Nicolas
author_facet Carter, Daniel
Trotignon, Nicolas
contents We introduce pathographs as a framework to study graph classes defined by forbidden structures, including forbidding induced subgraphs, minors, etc. Pathographs approximately generalize s-graphs of Lévêque--Lin--Maffray--Trotignon by the addition of two extra adjacency relations: one between subdivisible edges and vertices called spokes, and one between pairs of subdivisible edges called rungs. We consider the following decision problem: given a pathograph $\mathfrak{H}$ and a finite set of pathographs $\mathcal{F}$, is there an $\mathcal{F}$-free realization of $\mathfrak{H}$? This may be regarded as a generalization of the "graph class containment problem": given two graph classes $S$ and $S'$, is it the case that $S\subseteq S'$? We prove the pathograph realization problem is undecidable in general, but it is decidable in the case that $\mathfrak{H}$ has no rungs (but may have spokes), or if $\mathcal{F}$ is closed under adding edges, spokes, and rungs. We also discuss some potential applications to proving decomposition theorems.
format Preprint
id arxiv_https___arxiv_org_abs_2505_19871
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Pathographs and some (un)decidability results
Carter, Daniel
Trotignon, Nicolas
Combinatorics
Discrete Mathematics
Data Structures and Algorithms
05C85 (Primary) 68Q45, 05C75 (Secondary)
We introduce pathographs as a framework to study graph classes defined by forbidden structures, including forbidding induced subgraphs, minors, etc. Pathographs approximately generalize s-graphs of Lévêque--Lin--Maffray--Trotignon by the addition of two extra adjacency relations: one between subdivisible edges and vertices called spokes, and one between pairs of subdivisible edges called rungs. We consider the following decision problem: given a pathograph $\mathfrak{H}$ and a finite set of pathographs $\mathcal{F}$, is there an $\mathcal{F}$-free realization of $\mathfrak{H}$? This may be regarded as a generalization of the "graph class containment problem": given two graph classes $S$ and $S'$, is it the case that $S\subseteq S'$? We prove the pathograph realization problem is undecidable in general, but it is decidable in the case that $\mathfrak{H}$ has no rungs (but may have spokes), or if $\mathcal{F}$ is closed under adding edges, spokes, and rungs. We also discuss some potential applications to proving decomposition theorems.
title Pathographs and some (un)decidability results
topic Combinatorics
Discrete Mathematics
Data Structures and Algorithms
05C85 (Primary) 68Q45, 05C75 (Secondary)
url https://arxiv.org/abs/2505.19871