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Related papers: Canonical graph decompositions via coverings

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We propose a homology theory for locally compact spaces with ends in which the ends play a special role. The approach is motivated by results for graphs with ends, where it has been highly successful. But it was unclear how the original…

Algebraic Topology · Mathematics 2011-05-26 Reinhard Diestel , Philipp Sprüssel

In this paper, a new general decomposition theory inspired from modular graph decomposition is presented. Our main result shows that, within this general theory, most of the nice algorithmic tools developed for modular decomposition are…

Data Structures and Algorithms · Computer Science 2007-05-23 Binh Minh Bui Xuan , Michel Habib , Vincent Limouzy , Fabien De Montgolfier

We establish combinatorial characterizations of virtually torsion-free and virtually free groups using the canonical graph decomposition theory in \cite{DJKK22}. Our main results show that a finitely presented, residually finite group…

Group Theory · Mathematics 2026-03-06 R. Köhl , M. Reza Salarian

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

In this paper we discuss reconstruction problems for graphs. We develop some new ideas like isomorphic extension of isomorphic graphs, partitioning of vertex sets into sets of equivalent points, subdeck property, etc. and develop an…

General Mathematics · Mathematics 2011-10-21 Dhananjay P. Mehendale

We introduce a new decomposition of a graphs into quasi-4-connected components, where we call a graph quasi-4-connected if it is 3-connected and it only has separations of order 3 that remove a single vertex. Moreover, we give a cubic time…

Discrete Mathematics · Computer Science 2016-02-16 Martin Grohe

We prove that every graph which admits a tree-decomposition into finite parts has a rooted tree-decomposition into finite parts that is linked, tight and componental. As an application, we obtain that every graph without half-grid minor has…

Combinatorics · Mathematics 2024-05-14 Sandra Albrechtsen , Raphael W. Jacobs , Paul Knappe , Max Pitz

We introduce the concept of a class of graphs, or more generally, relational structures, being locally tree-decomposable. There are numerous examples of locally tree-decomposable classes, among them the class of planar graphs and all…

Data Structures and Algorithms · Computer Science 2007-05-23 Markus Frick , Martin Grohe

We prove that any one-ended, locally finite Cayley graph with non-torsion generators admits a decomposition into edge-disjoint Hamiltonian (i.e. spanning) double-rays. In particular, the $n$-dimensional grid $\mathbb{Z}^n$ admits a…

Combinatorics · Mathematics 2017-09-28 Joshua Erde , Florian Lehner , Max Pitz

This paper is the continuation of the research of the author and his colleagues of the {\it canonical} decomposition of graphs. The idea of the canonical decomposition is to define the binary operation on the set of graphs and to represent…

Combinatorics · Mathematics 2016-07-19 Pavel Skums

In this article we study the deformation of finite maps and show how to use this deformation theory to construct varieties with given invariants in a projective space. Among other things, we prove a criterion that determines when a finite…

Algebraic Geometry · Mathematics 2010-06-08 F. J. Gallego , M. González , B. P. Purnaprajna

In this paper, we present a general, multistage framework for graphical model approximation using a cascade of models such as trees. In particular, we look at the problem of covariance matrix approximation for Gaussian distributions as…

Information Theory · Computer Science 2018-08-13 Navid Tafaghodi Khajavi , Anthony Kuh

We give new decomposition theorems for classes of graphs that can be transduced in first-order logic from classes of sparse graphs -- more precisely, from classes of bounded expansion and from nowhere dense classes. In both cases, the…

Logic in Computer Science · Computer Science 2022-01-27 Jan Dreier , Jakub Gajarský , Sandra Kiefer , Michał Pilipczuk , Szymon Toruńczyk

A connected, locally finite graph $\Gamma$ is a Cayley--Abels graph for a totally disconnected, locally compact group $G$ if $G$ acts vertex-transitively with compact, open vertex stabilizers on $\Gamma$. Define the minimal degree of $G$ as…

Group Theory · Mathematics 2021-05-27 Arnbjörg Soffía Árnadóttir , Waltraud Lederle , Rögnvaldur G. Möller

The famous Gallai's Conjecture states that any connected graph with n vertices has a path decomposition containing at most (n+1)/2 paths. In this note, we explore graphs generated from removing edges from complete graphs. We first provide…

Combinatorics · Mathematics 2022-11-01 Hua Wang , Andrew Zhang

The modular decomposition of a graph is a canonical representation of its modules. Algorithms for computing the modular decomposition of directed and undirected graphs differ significantly, with the undirected case being simpler, and…

Discrete Mathematics · Computer Science 2017-10-13 Henning Koehler

A digraph is semicomplete if any two vertices are connected by at least one arc and is locally semicomplete if the out-neighbourhood and the in-neighbourhood of any vertex induce a semicomplete digraph. In this paper we study various…

Combinatorics · Mathematics 2022-12-07 Pierre Aboulker , Guillaume Aubian , Pierre Charbit

It is well-known that a complete Riemannian manifold M which is locally isometric to a symmetric space is covered by a symmetric space. Here we prove that a discrete version of this property (called local to global rigidity) holds for a…

Metric Geometry · Mathematics 2019-11-26 Mikael de la Salle , Romain Tessera

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

This article establishes that the split decomposition of graphs introduced by Cunnigham, is definable in Monadic Second-Order Logic.This result is actually an instance of a more general result covering canonical graph decompositions like…

Logic in Computer Science · Computer Science 2017-01-11 Bruno Courcelle