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Related papers: A note on forbidding clique immersions

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We consider the problem of how much edge connectivity is necessary to force a graph G to contain a fixed graph H as an immersion. We show that if the maximum degree in H is D, then all the examples of D-edge connected graphs which do not…

Combinatorics · Mathematics 2014-01-14 Daniel Marx , Paul Wollan

The immersion relation is a partial ordering relation on graphs that is weaker than the topological minor relation in the sense that if a graph $G$ contains a graph $H$ as a topological minor, then it also contains it as an immersion but…

Combinatorics · Mathematics 2012-07-24 Archontia C. Giannopoulou , Marcin Kaminski , Dimitrios M. Thilikos

Grohe and Marx proved that if G does not contain H as a topological minor, then there exist constants g=O(|V(H)|^4), D and t depending only on H such that G is a clique sum of graphs that either contain at most t vertices of degree greater…

Combinatorics · Mathematics 2012-09-04 Zdenek Dvorak

The central theorem of topological graph theory states that the graph minor relation is a well-quasi-order on graphs. It has far-reaching consequences, in particular in the study of graph structures and the design of (parameterized)…

Computational Geometry · Computer Science 2025-12-04 Corentin Lunel , Clément Maria

A major step in the graph minors theory of Robertson and Seymour is the transition from the Grid Theorem which, in some sense uniquely, describes areas of large treewidth within a graph, to a notion of local flatness of these areas in form…

Combinatorics · Mathematics 2021-10-15 Archontia C. Giannopoulou , Sebastian Wiederrecht

We consider sufficient conditions for the existence of $k$-th powers of Hamiltonian cycles in $n$-vertex graphs $G$ with minimum degree $\mu n$ for arbitrarily small $\mu>0$. About 20 years ago Koml\'os, Sark\"ozy, and Szemer\'edi resolved…

Combinatorics · Mathematics 2019-10-01 Oliver Ebsen , Giulia S. Maesaka , Christian Reiher , Mathias Schacht , Bjarne Schülke

This paper gives a precise structure theorem for the class of graphs which do not contain $W_4$ as an immersion. This strengthens a previous result of Belmonte at al. that gives a rough description of this class. In fact, we prove a…

Combinatorics · Mathematics 2018-10-31 Matt DeVos , Mahdieh Malekian

The Graph Minors Structure Theorem (GMST) of Robertson and Seymour states that for every graph $H,$ any $H$-minor-free graph $G$ has a tree-decomposition of bounded adhesion such that the torso of every bag embeds in a surface $\Sigma$…

Combinatorics · Mathematics 2026-01-28 Dimitrios M. Thilikos , Sebastian Wiederrecht

Robertson and Seymour proved that for every finite tree $H$, there exists $k$ such that every finite graph $G$ with no $H$ minor has path-width at most $k$; and conversely, for every integer $k$, there is a finite tree $H$ such that every…

Combinatorics · Mathematics 2025-09-16 Tung Nguyen , Alex Scott , Paul Seymour

Let $\mathcal{D}_k$ be the class of graphs for which every minor has minimum degree at most $k$. Then $\mathcal{D}_k$ is closed under taking minors. By the Robertson-Seymour graph minor theorem, $\mathcal{D}_k$ is characterised by a finite…

Combinatorics · Mathematics 2011-06-07 Gašper Fijavž , David R. Wood

The Graph Minor Theorem of Robertson and Seymour asserts that any graph property, whatsoever, is determined by an associated finite list of graphs. We view this as an impressive generalization of Kuratowski's theorem, which characterizes…

Combinatorics · Mathematics 2018-11-27 Thomas W. Mattman

A graph H is strongly immersed in G if H is obtained from G by a sequence of vertex splittings (i.e., lifting some pairs of incident edges and removing the vertex) and edge removals. Equivalently, vertices of H are mapped to distinct…

Combinatorics · Mathematics 2014-11-04 Zdenek Dvorak , Paul Wollan

This is a companion paper to the paper "Hyperstability in the Erdos-Sos Conjecture". In that paper the following rough structure theorem was proved for graphs G containing no copy of a bounded degree tree T: from any such G, one can delete…

Combinatorics · Mathematics 2024-09-24 Alexey Pokrovskiy

The recent paper "Linear Connectivity Forces Large Complete Bipartite Minors" by Boehme et al. relies on a structure theorem for graphs with no H-minor. The sketch provided of how to deduce this theorem from the work of Robertson and…

Combinatorics · Mathematics 2009-06-16 Jan-Oliver Fröhlich , Theodor Müller

We prove a structural characterization of graphs that forbid a fixed graph $H$ as an immersion and can be embedded in a surface of Euler genus $\gamma$. In particular, we prove that a graph $G$ that excludes some connected graph $H$ as an…

Combinatorics · Mathematics 2013-03-27 Archontia C. Giannopoulou , Marcin Kaminski , Dimitrios M. Thilikos

An immersion of a graph H in another graph G is a one-to-one mapping phi:V(H)->V(G) and a collection of edge-disjoint paths in G, one for each edge of H, such that the path P_{uv} corresponding to the edge uv has endpoints phi(u) and…

Combinatorics · Mathematics 2015-12-03 Zdeněk Dvořák , Liana Yepremyan

A graph $G$ contains another graph $H$ as an immersion if $H$ can be obtained from a subgraph of $G$ by splitting off edges and removing isolated vertices. There is an obvious necessary degree condition for the immersion containment: if $G$…

Combinatorics · Mathematics 2022-09-27 Chun-Hung Liu

A graph $G$ contains $H$ as an \emph{immersion} if there is an injective mapping $\phi: V(H)\rightarrow V(G)$ such that for each edge $uv\in E(H)$, there is a path $P_{uv}$ in $G$ joining vertices $\phi(u)$ and $\phi(v)$, and all the paths…

Combinatorics · Mathematics 2022-08-02 Hong Liu , Guanghui Wang , Donglei Yang

In this article we consider the relationship between vertex coloring and the immersion order. Specifically, a conjecture proposed by Abu-Khzam and Langston in 2003, which says that the complete graph with $t$ vertices can be immersed in any…

Combinatorics · Mathematics 2017-01-03 Sylvia Vergara

We show that a graph contains a large wall as a strong immersion minor if and only if the graph does not admit a tree-cut decomposition of small `width', which is measured in terms of its adhesion and the path-likeness of its torsos.

Combinatorics · Mathematics 2025-01-22 Reinhard Diestel , Raphael W. Jacobs , Paul Knappe , Paul Wollan