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Related papers: Clifford's Theorem for graphs

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In graph theory, knowing the number of complete subgraphs with r vertices that a graph g has, limits the number of its complete subgraphs with s vertices, for s > r. A useful upper bound is provided by the Kruskal-Katona theorem, but this…

Combinatorics · Mathematics 2018-12-31 Robert Cowen

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

We investigate straight-line drawings of topological graphs that consist of a planar graph plus one edge, also called almost-planar graphs. We present a characterization of such graphs that admit a straight-line drawing. The…

Computational Geometry · Computer Science 2015-07-01 Peter Eades , Seok-Hee Hong , Giuseppe Liotta , Naoki Katoh , Sheung-Hung Poon

We prove a general duality theorem for tangle-like dense objects in combinatorial structures such as graphs and matroids. This paper continues, and assumes familiarity with, the theory developed in [6]

Combinatorics · Mathematics 2014-06-17 Reinhard Diestel , Sang-il Oum

Fr\"oberg's classical theorem about edge ideals with $2$-linear resolution can be regarded as a classification of graphs whose edge ideals have linearity defect zero. Extending his theorem, we classify all graphs whose edge ideals have…

Commutative Algebra · Mathematics 2016-01-19 Hop D. Nguyen , Thanh Vu

Let $G$ be a graph on $n$ nodes. In this note, we prove that if $G$ is $(r+1)$-vertex connected, $1 \leq r \leq n-2$, then there exists a configuration $p$ in general position in $R^r$ such that the bar framework $(G,p)$ is universally…

Metric Geometry · Mathematics 2014-08-18 A. Y. Alfakih

A vertex transitive graph $\Gamma$ is said to be $2$-distance transitive if for each vertex $u$, the group of automorphisms of $\Gamma$ fixing the vertex $u$ acts transitively on the set of vertices at distance $1$ and $2$ from $u$, while…

Combinatorics · Mathematics 2024-03-05 Jun-Jie Huang , Yan-Quan Feng , Jin-Xin Zhou , Fu-Gang Yin

Algebraic curves have a discrete analogue in finite graphs. Pursuing this analogy we prove a Torelli theorem for graphs. Namely, we show that two graphs have the same Albanese torus if and only if the graphs obtained from them by…

Combinatorics · Mathematics 2019-12-19 Lucia Caporaso , Filippo Viviani

This is an introduction to geometric algebra, an alternative to traditional vector algebra that expands on it in two ways: 1. In addition to scalars and vectors, it defines new objects representing subspaces of any dimension. 2. It defines…

Mathematical Physics · Physics 2012-05-29 Eric Chisolm

A keyring is a graph obtained by appending $r \geq 1$ leaves to one of the vertices of a cycle. We prove that for every $r \leq (k-1)/2$, any graph with average degree more than $k-1$ contains a keyring with $r$ leaves and at least $k$…

Combinatorics · Mathematics 2018-07-03 Alexander Sidorenko

A linear vector model of gravitation is introduced in the context of quantum physics as a generalization of electromagnetism. The gravitoelectromagnetic gauge symmetry corresponds to a hyperbolic unitary extension of the usual complex phase…

General Relativity and Quantum Cosmology · Physics 2014-07-01 S. Ulrych

The geometric calculus based on Clifford algebra is a very useful tool for geometry and physics. It describes a geometric structure which is much richer than the ordinary geometry of spacetime. A Clifford manifold (C-space) consists not…

General Relativity and Quantum Cosmology · Physics 2011-08-17 Matej Pavsic

Temporal graphs are graphs where the presence or properties of their vertices and edges change over time. When time is discrete, a temporal graph can be defined as a sequence of static graphs over a discrete time span, called lifetime, or…

Data Structures and Algorithms · Computer Science 2026-05-05 Binh-Minh Bui-Xuan , Florent Krasnopol , Bruno Monasson , Nathalie Sznajder

Comparability graphs are a popular class of graphs. We introduce as the digraph analogue of comparability graphs the class of comparability digraphs. We show that many concepts such as implication classes and the knotting graph for a…

Combinatorics · Mathematics 2022-04-05 Xiao-Lu Gao , Jing Huang , Shou-Jun Xu

We apply a recent duality theorem for tangles in abstract separation systems to derive tangle-type duality theorems for width-parameters in graphs and matroids. We further derive a duality theorem for the existence of clusters in large data…

Combinatorics · Mathematics 2020-01-24 Reinhard Diestel , Sang-il Oum

A graph $\Gamma$ is called $G$-symmetric if it admits $G$ as a group of automorphisms acting transitively on the set of ordered pairs of adjacent vertices. We give a classification of $G$-symmetric graphs $\Gamma$ with $V(\Gamma)$ admitting…

Group Theory · Mathematics 2017-06-19 Teng Fang , Xin Gui Fang , Binzhou Xia , Sanming Zhou

That preferred-frame theory accounts for special relativity and reduces to it if the gravitation field cancels. Starting from an interpretation of gravity as a pressure force, it is based on just one scalar field. This scalar gives the…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Mayeul Arminjon

In this paper we show how to describe the general theory of a linear metric compatible connection with the theory of Clifford valued differential forms. This is done by realizing that for each spacetime point the Lie algebra of Clifford…

Mathematical Physics · Physics 2011-07-19 Waldyr A. Rodrigues , Edmundo Capelas de Oliveira

This paper examines a pair of bent functions on $\mathbb{Z}_2^{2m}$ and their relationship to a necessary condition for the existence of an automorphism of an edge-coloured graph whose colours are defined by the properties of a canonical…

Combinatorics · Mathematics 2019-04-22 Paul C. Leopardi

In this paper we focus on the description of the automorphism group $\Gamma_{\parallel}$ of a Clifford-like parallelism $\parallel$ on a $3$-dimensional projective double space…

Algebraic Geometry · Mathematics 2024-02-02 Hans Havlicek , Stefano Pasotti , Silvia Pianta
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