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Related papers: Critical and flow-critical snarks coincide

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A snark -- connected cubic graph with chromatic index $4$ -- is critical if the graph resulting from the removal of any pair of distinct adjacent vertices is $3$-edge-colourable; it is bicritical if the same is true for any pair of distinct…

Combinatorics · Mathematics 2024-06-25 Ján Mazák , Jozef Rajník , Martin Škoviera

In this paper we further our understanding of the structure of class two cubic graphs, or snarks, as they are commonly known. We do this by investigating their 3-critical subgraphs, or as we will call them, minimal conflicting subgraphs. We…

Combinatorics · Mathematics 2022-01-20 Imran Allie

The colouring defect of a cubic graph, introduced by Steffen in 2015, is the minimum number of edges that are left uncovered by any set of three perfect matchings. Since a cubic graph has defect $0$ if and only if it is $3$-edge-colourable,…

Combinatorics · Mathematics 2022-03-17 Ján Karabáš , Edita Máčajová , Roman Nedela , Martin Škoviera

Cavity flow problems in two dimensions, as well as in the axially symmetric three-dimensional case, have been extensively studied in the literature from a qualitative perspective. While numerous results exist concerning minimizers or stable…

Analysis of PDEs · Mathematics 2025-09-03 Masoud Bayrami , Morteza Fotouhi , Parisa Vosooqnejad

Snarks are $2$-connected cubic graphs that do not admit a proper $3$-edge-coloring. For a cubic graph $G$, its resistance $r(G)$ is the minimum number of edges whose removal results in a $3$-edge-colorable graph, while its flow resistance…

Combinatorics · Mathematics 2026-04-27 Davide Mattiolo , Pietro Negrini , Silvia M. C. Pagani

A bridgeless cubic graph $G$ is said to have a 2-bisection if there exists a 2-vertex-colouring of $G$ (not necessarily proper) such that: (i) the colour classes have the same cardinality, and (ii) the monochromatic components are either an…

Combinatorics · Mathematics 2022-09-16 Jean Paul Zerafa

The essential requirement for a cubic graph to be called a snark is that it can not be edge-coloured with three colours. To avoid trivial cases, varying restrictions on the connectivity are imposed. Snarks are not only interesting in…

Combinatorics · Mathematics 2026-03-19 Gunnar Brinkmann , Steven Van Overberghe

By combining accurate liquid-vapor coexistence and heat-capacity data, we have unambiguously separated two non-analytical contributions of liquid-gas asymmetry in fluid criticality and proved the validity of "complete scaling" [Fisher et…

Statistical Mechanics · Physics 2009-11-11 Mikhail A. Anisimov , Jingtao Wang

There are many hard conjectures in graph theory, like Tutte's 5-flow conjecture, and the 5-cycle double cover conjecture, which would be true in general if they would be true for cubic graphs. Since most of them are trivially true for…

Combinatorics · Mathematics 2017-02-24 M. A. Fiol , G. Mazzuoccolo , E. Steffen

We evidence critical fluctuations in the strain-rate of granular flows that are weakly vibrated. Strikingly, the critical point arises at {\em finite} values of the mean strain rate and vibration strength, far away from the yielding…

Soft Condensed Matter · Physics 2016-11-09 Geert Wortel , Olivier Dauchot , Martin van Hecke

A {\em snark} is a cubic cyclically 4-edge connected graph with edge chromatic number four and girth at least five. We say that a graph $G$ is {\em odd 2-factored} if for each 2-factor F of G each cycle of F is odd. In this paper, we…

Combinatorics · Mathematics 2015-01-13 M. Abreu , D. Labbate , R. Rizzi , J. Sheehan

Biological systems with many components often exhibit seemingly critical behaviors, characterized by atypically large correlated fluctuations. Yet the underlying causes remain unclear. Here we define and examine two types of criticality.…

Biological Physics · Physics 2025-02-26 Vudtiwat Ngampruetikorn , Ilya Nemenman , David J. Schwab

In this note we construct two infinite snark families which have high oddness and low circumference compared to the number of vertices. Using this construction, we also give a counterexample to a suggested strengthening of Fulkerson's…

Combinatorics · Mathematics 2012-03-12 Jonas Hägglund

Critical points of an invariant function may or may not be symmetric. We prove, however, that if a symmetric critical point exists, those adjacent to it are generically symmetry breaking. This mathematical mechanism is shown to carry…

Machine Learning · Computer Science 2024-08-27 Yossi Arjevani

For integers $a\ge 2b>0$, a \emph{circular $a/b$-flow} is a flow that takes values from $\{\pm b, \pm(b+1), \dots, \pm(a-b)\}$. The Planar Circular Flow Conjecture states that every $2k$-edge-connected planar graph admits a circular…

Combinatorics · Mathematics 2020-07-14 Daniel W. Cranston , Jiaao Li

A circular nowhere-zero $r$-flow on a bridgeless graph $G$ is an orientation of the edges and an assignment of real values from $[1, r-1]$ to the edges in such a way that the sum of incoming values equals the sum of outgoing values for…

Combinatorics · Mathematics 2021-09-08 Robert Lukoťka

The thermodynamic behavior of a fluid near a vapor-liquid and, hence, asymmetric critical point is discussed within a general ``complete'' scaling theory incorporating pressure mixing in the nonlinear scaling fields as well as corrections…

Statistical Mechanics · Physics 2009-11-07 Young C. Kim , Michael E. Fisher , G. Orkoulas

Many studies have found evidence that the brain operates at a critical point, a processus known as self-organized criticality. A recent paper found remarkable scalings suggestive of criticality in systems as different as neural cultures,…

Neurons and Cognition · Quantitative Biology 2020-12-29 Alain Destexhe , Jonathan D. Touboul

A rigorous understanding of brain dynamics and function requires a conceptual bridge between multiple levels of organization, including neural spiking and network-level population activity. Mounting evidence suggests that neural networks of…

Neurons and Cognition · Quantitative Biology 2016-10-11 Yahya Karimipanah , Zhengyu Ma , Ralf Wessel

The aim of this paper is to classify all snarks up to order $36$ and explain the reasons of their uncolourability. The crucial part of our approach is a computer-assisted structural analysis of cyclically $5$-connected critical snarks,…

Discrete Mathematics · Computer Science 2021-12-09 Ján Mazák , Jozef Rajník , Martin Škoviera
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