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Related papers: Graph rigidity properties of Ramanujan graphs

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Rigidity is the property of a structure that does not flex. It is well studied in discrete geometry and mechanics, and has applications in material science, engineering and biological sciences. A bar-and-joint framework is a pair $(G,p)$ of…

Combinatorics · Mathematics 2021-03-02 Sebastian M. Cioabă , Sean Dewar , Xiaofeng Gu

Over the past half century, the rigidity of graphs in $R^2$ has aroused a great deal of interest. Lov\'{a}sz and Yemini (1982) proved that every $6$-connected graph is rigid in $R^2$. Jackson and Jord\'{a}n (2005) provided a similar…

Combinatorics · Mathematics 2022-05-27 Dandan Fan , Xueyi Huang , Huiqiu Lin

We investigate how to find generic and globally rigid realizations of graphs in $\mathbb{R}^d$ based on elementary geometric observations. Our arguments lead to new proofs of a combinatorial characterization of the global rigidity of graphs…

Combinatorics · Mathematics 2014-08-12 Shin-ichi Tanigawa

Tanigawa (2016) showed that vertex-redundant rigidity of a graph implies its global rigidity in arbitrary dimension. We extend this result to periodic graphs under fixed lattice representations. A periodic graph is vertex-redundantly rigid…

Metric Geometry · Mathematics 2018-04-24 Viktoria E. Kaszanitzky , Csaba Kiraly , Bernd Schulze

A $d$-dimensional bar-and-joint framework $(G,p)$ with underlying graph $G$ is called universally rigid if all realizations of $G$ with the same edge lengths, in all dimensions, are congruent to $(G,p)$. A graph $G$ is said to be…

Combinatorics · Mathematics 2025-02-07 Guilherme Zeus Dantas e Moura , Tibor Jordán , Corwin Silverman

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

We show that any graph that is generically globally rigid in $\mathbb{R}^d$ has a realization in $\mathbb{R}^d$ that is both generic and universally rigid. This also implies that the graph also must have a realization in $\mathbb{R}^d$ that…

Metric Geometry · Mathematics 2018-08-15 Robert Connelly , Steven J. Gortler , Louis Theran

A graph $G = (V,E)$ is globally rigid in $\mathbb{R}^d$ if for any generic placement $p : V \rightarrow \mathbb{R}^d$ of the vertices, the edge lengths $||p(u) - p(v)||, uv \in E$ uniquely determine $p$, up to congruence. In this paper we…

Combinatorics · Mathematics 2025-02-14 Dániel Garamvölgyi , Tibor Jordán

This note gives a detailed proof of the following statement. Let $d\in \mathbb{N}$ and $m,n \ge d + 1$, with $m + n \ge \binom{d+2}{2} + 1$. Then the complete bipartite graph $K_{m,n}$ is generically globally rigid in dimension $d$.

Metric Geometry · Mathematics 2021-05-05 Robert Connelly , Steven J. Gortler , Louis Theran

A graph is said to be globally rigid if almost all embeddings of the graph's vertices in the Euclidean plane will define a system of edge-length equations with a unique (up to isometry) solution. In 2007, Jackson, Servatius and Servatius…

Combinatorics · Mathematics 2024-01-29 Sean Dewar

We examine the generic local and global rigidity of various graphs in R^d. Bruce Hendrickson showed that some necessary conditions for generic global rigidity are (d+1)-connectedness and generic redundant rigidity and hypothesized that they…

Metric Geometry · Mathematics 2015-03-13 Samuel Frank , Jiayang Jiang

In 1992, Hendrickson proved that (d+1)-connectivity and redundant rigidity are necessary conditions for a generic (non-complete) bar-joint framework to be globally rigid in $\mathbb{R}^d$. Jackson and Jordan confirmed in 2005 that these…

Combinatorics · Mathematics 2019-09-17 Viktoria E. Kaszanitzky , Bernd Schulze , Shin-ichi Tanigawa

A graph is said to be globally rigid in $d$-dimensional space if almost all of its embeddings are unique up to isometries. If a graph has enough automorphisms to send any of its vertices into any other, then it is called vertex-transitive.…

Combinatorics · Mathematics 2026-01-19 Angelo El Saliby

We present a generalization of the construction of graphs by Lubotzky, Phillips and Sarnak in their celebrated article "Ramanujan graphs". The new approach consists in using octonion algebras rather than quaternions. A key tool is the…

Combinatorics · Mathematics 2012-02-06 Xavier Dahan , Jean-Pierre Tillich

A framework (a straight-line embedding of a graph into a normed space allowing edges to cross) is globally rigid if any other framework with the same edge lengths with respect to the chosen norm is an isometric copy. We investigate global…

Metric Geometry · Mathematics 2025-04-04 Sean Dewar

A d-dimensional framework is a graph and a map from its vertices to E^d. Such a framework is globally rigid if it is the only framework in E^d with the same graph and edge lengths, up to rigid motions. For which underlying graphs is a…

Metric Geometry · Mathematics 2021-10-13 Steven J. Gortler , Alexander D. Healy , Dylan P. Thurston

We introduce and study a generalization of conformal rigidity for graphs. A graph is $k$-conformally rigid if the uniform edge weights simultaneously maximize the sum of the $k$ smallest nontrivial Laplacian eigenvalues and minimize the sum…

Combinatorics · Mathematics 2026-05-12 Henrique Assumpção , Gabriel Coutinho , Chris Godsil

We prove that $q+1$-regular Morgenstern Ramanujan graphs $X^{q,g}$ (depending on $g\in\mathbb{F}_q[t]$) have diameter at most $\left(\frac{4}{3}+\varepsilon\right)\log_{q}|X^{q,g}|+O_{\varepsilon}(1)$ (at least for odd $q$ and irreducible…

Number Theory · Mathematics 2020-04-28 Naser T. Sardari , Masoud Zargar

The 2-dimensional global rigidity has been shown to be equivalent to 3-connectedness and redundant rigidity by a combination of two results due to Jackson and Jord\'an, and Connelly, respectively. By the characterization, a theorem of…

Combinatorics · Mathematics 2021-06-17 Xiaofeng Gu , Wei Meng , Martin Rolek , Yue Wang , Gexin Yu

We prove that every (6k + 2l, 2k)-connected simple graph contains k rigid and l connected edge-disjoint spanning subgraphs. This implies a theorem of Jackson and Jord\'an [4] and a theorem of Jord\'an [6] on packing of rigid spanning…

Discrete Mathematics · Computer Science 2012-01-19 Joseph Cheriyan , Olivier Durand de Gevigney , Zoltán Szigeti
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