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Related papers: A short proof of Seymour's 6-flow theorem

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This is a short note describing what I believe is a serious gap in Stanfield's proof of Sachs' conjecture that every linklessly embeddable graph has a linear linkless embedding in $\mathbb{R}^3$.

Geometric Topology · Mathematics 2026-03-12 Ramin Naimi

Jaeger, Linial, Payan, and Tarsi introduced the notion of $A$-connectivity for graphs in 1992, and proved a decomposition for cubic graphs from which $A$-connectivity follows for all 3-edge-connected graphs when $|A|\geq 6$. The concept of…

Combinatorics · Mathematics 2023-06-08 Alejandra Brewer Castano , Jessica McDonald , Kathryn Nurse

A low-dimensional version of our main result is the following `converse' of the Conway-Gordon-Sachs Theorem on intrinsic linking of the graph $K_6$ in 3-space: For any integer $z$ there are 6 points $1,2,3,4,5,6$ in 3-space, of which every…

Geometric Topology · Mathematics 2026-01-08 R. Karasev , A. Skopenkov

We show that if a graph is k-edge-connected, and we adjoin to it another graph satisfying a "contracted diameter less or equal to 2" condition, with minimal degree greater or equal to k, and some natural hypothesis on the edges connecting…

General Mathematics · Mathematics 2008-12-18 José Ignacio Alvarez-Hamelin , Jorge Rodolfo Busch

We develop a theory of confluence of graphs. We describe an algorithm for proving that a given system of reduction rules for abstract graphs and graphs in surfaces is locally confluent. We apply this algorithm to show that each simple Lie…

Quantum Algebra · Mathematics 2014-10-01 Adam S. Sikora , Bruce W. Westbury

It is shown that there are infinitely many connected vertex-transitive graphs that have no Hamilton decomposition, including infinitely many Cayley graphs of valency 6, and including Cayley graphs of arbitrarily large valency.

Combinatorics · Mathematics 2014-11-13 Darryn Bryant , Matthew Dean

Let $G$ be a bridgeless cubic graph. In 2023, the three authors solved a conjecture (also known as the $S_4$-Conjecture) made by Mazzuoccolo in 2013: there exist two perfect matchings of $G$ such that the complement of their union is a…

Combinatorics · Mathematics 2025-02-14 František Kardoš , Edita Máčajová , Jean Paul Zerafa

An even-cycle decomposition of a graph G is a partition of E(G) into cycles of even length. Evidently, every Eulerian bipartite graph has an even-cycle decomposition. Seymour (1981) proved that every 2-connected loopless Eulerian planar…

Combinatorics · Mathematics 2018-05-16 Tony Huynh , Sang-il Oum , Maryam Verdian-Rizi

We consider when automorphisms of a graph can be induced by homeomorphisms of embeddings of the graph in a $3$-manifold. In particular, we prove that every automorphism of a graph is induced by a homeomorphism of some embedding of the graph…

Geometric Topology · Mathematics 2021-12-15 Erica Flapan , Song Yu

We study the gordian graph of all knots in $\R^3$: two knots are adjacent if they differ by a single crossing change. We prove that this graph contains isometrically an infinite countable tree with infinite valency, and that the complement…

Geometric Topology · Mathematics 2007-05-23 Julien Marche

A class A of labelled graphs is bridge-addable if for all graphs G in A and all vertices u and v in distinct connected components of G, the graph obtained by adding an edge between u and u is also in A; the class A is monotone if for all G…

Combinatorics · Mathematics 2011-10-04 Louigi Addario Berry , Colin McDiarmid , Bruce Reed

We establish splitter theorems for graph immersions for two families of graphs, $k$-edge-connected graphs, with $k$ even, and 3-edge-connected, internally 4-edge-connected graphs. As a corollary, we prove that every $3$-edge-connected,…

Combinatorics · Mathematics 2025-07-09 Matt DeVos , Mahdieh Malekian

We show that the edges of every 3-connected planar graph except $K_4$ can be colored with two colors in such a way that the graph has no color preserving automorphisms. Also, we characterize all graphs which have the property that their…

Combinatorics · Mathematics 2016-08-26 Erica Flapan , Sarah Rundell , Madeline Wyse

We adapt the classical 3-decomposition of any 2-connected graph to the case of simple graphs (no loops or multiple edges). By analogy with the block-cutpoint tree of a connected graph, we deduce from this decomposition a bicolored tree…

Combinatorics · Mathematics 2010-12-24 Andrei Gagarin , Gilbert Labelle , Pierre Leroux , Timothy Walsh

We prove that the matching measure of an infinite vertex-transitive connected graph has no atoms. Generalizing the results of Salez, we show that for an ergodic non-amenable unimodular random rooted graph with uniformly bounded degrees, the…

Probability · Mathematics 2020-05-26 Ferenc Bencs , András Mészáros

We show that Vizing's Theorem holds in the Borel context for graphs induced by actions of 2-ended groups, and ask whether it holds more generally for everywhere two ended Borel graphs.

Logic · Mathematics 2021-02-01 Felix Weilacher

Ore's Theorem states that if $G$ is an $n$-vertex graph and every pair of non-adjacent vertices has degree sum at least $n$, then $G$ is Hamiltonian. A $[3]$-graph is a hypergraph in which every edge contains at most $3$ vertices. In this…

Combinatorics · Mathematics 2025-05-20 Yupei Li , Linyuan Lu , Ruth Luo

We study the following conjecture of Matt DeVos: If there is a graph homomorphism from Cayley graph Cay(M, B) to another Cayley graph Cay(M', B') then every graph with an (M, B)-flow has an (M', B')-flow. This conjecture was originally…

Combinatorics · Mathematics 2019-01-11 Radek Hušek , Robert Šámal

In this article, we prove two "global existence and full convergence theorems" for flow lines of the M\"obius-invariant Willmore flow, and we use these results, in order to prove that fully and smoothly convergent flow lines of the…

Differential Geometry · Mathematics 2026-02-03 Ruben Jakob

The 2-Decomposition Conjecture, equivalent to the 3-Decomposition Conjecture stated in 2011 by Hoffmann-Ostenhof, claims that every connected graph $G$ with vertices of degree 2 and 3, for which $G \setminus E(C)$ is disconnected for every…

Combinatorics · Mathematics 2023-09-19 F. Botler , A. Jiménez , M. Sambinelli , Y. Wakabayashi