English
Related papers

Related papers: Graph rigidity for unitarily invariant matrix norm…

200 papers

The \textit{toughness} $t(G)$ of a graph $G$ is a measure of its connectivity that is closely related to Hamiltonicity. Brouwer proved the lower bound $t(G) > \ell / \lambda - 2$ on the toughness of any connected $\ell$-regular graph, where…

We define the notion of affine rigidity of a hypergraph and prove a variety of fundamental results for this notion. First, we show that affine rigidity can be determined by the rank of a specific matrix which implies that affine rigidity is…

Computational Geometry · Computer Science 2013-08-14 Steven J. Gortler , Craig Gotsman , Ligang Liu , Dylan P. Thurston

We define periodic frameworks as graphs on the torus, using the language of gain graphs. We present some fundamental definitions and results about the infinitesimal rigidity of graphs on a torus of fixed size and shape, and find necessary…

Metric Geometry · Mathematics 2012-03-01 Elissa Ross

The maximum likelihood threshold of a graph is the smallest number of data points that guarantees that maximum likelihood estimates exist almost surely in the Gaussian graphical model associated to the graph. We show that this graph…

Combinatorics · Mathematics 2015-09-17 Elizabeth Gross , Seth Sullivant

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 describe a very simple condition that is necessary for the universal rigidity of a complete bipartite framework $(K(n,m),p,q)$. This condition is also sufficient for universal rigidity under a variety of weak assumptions, such as general…

Metric Geometry · Mathematics 2016-10-14 Robert Connelly , Steven J. Gortler

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

Jord\'an and Tanigawa recently introduced the $d$-dimensional algebraic connectivity $a_d(G)$ of a graph $G$. This is a quantitative measure of the $d$-dimensional rigidity of $G$ which generalizes the well-studied notion of spectral…

Combinatorics · Mathematics 2023-04-05 Alan Lew , Eran Nevo , Yuval Peled , Orit E. Raz

We study the problem of finding the minimal (maximal) genus for a surface where a given four-valent graph with fixed opposite edge structure can be embedded into. We find several partial relations and give new reformulations in…

Combinatorics · Mathematics 2008-04-29 Vassily Olegovich Manturov

This article is concerned with the rigidity properties of geometric realizations of incidence geometries of rank two as points and lines in the Euclidean plane; we care about the distance being preserved among collinear points. We discuss…

Combinatorics · Mathematics 2022-04-28 Signe Lundqvist , Klara Stokes , Lars-Daniel Öhman

In this paper we establish combinatorial characterisations of symmetry-generic infinitesimally rigid frameworks in the Euclidean plane for rotational groups of order 4 and 6, and of odd order between 5 and 1000, where a joint may lie at the…

Combinatorics · Mathematics 2024-10-11 Alison La Porta , Bernd Schulze

Combinatorial characterisations of minimal rigidity are obtained for symmetric 2-dimensional bar-joint frameworks with either $\ell^1$ or $\ell^\infty$ distance constraints. The characterisations are expressed in terms of symmetric tree…

Combinatorics · Mathematics 2016-04-01 Derek Kitson , Bernd Schulze

In this article we consider resistance matrix of a connected graph. For unweighted graph we study some necessary and sufficient conditions for resistance regular graphs. Also we find some relationship between Laplacian matrix and resistance…

Combinatorics · Mathematics 2018-03-28 Deepak Sarma

We investigate the structure of conformally rigid graphs. Graphs are conformally rigid if introducing edge weights cannot increase (decrease) the second (last) eigenvalue of the Graph Laplacian. Edge-transitive graphs and distance-regular…

Combinatorics · Mathematics 2025-06-26 João Gouveia , Stefan Steinerberger , Rekha R. Thomas

We formulate the notion of an isomorphism of GKM graphs. We then show that two GKM graphs have isomorphic graph equivariant cohomology algebras if and only if the graphs are isomorphic.

Algebraic Topology · Mathematics 2019-12-30 Matthias Franz , Hitoshi Yamanaka

The graph entropy describes the structural information of graph. Motivated by the definition of graph entropy in general graphs, the graph entropy of hypergraphs based on Laplacian degree are defined. Some results on graph entropy of simple…

Combinatorics · Mathematics 2020-03-30 Pengli Lu , Yulong Xue

We use a new coloured multi-graph constructive method to prove that every 2-tree decomposition can be realised in the plane as a bar-joint framework which is minimally rigid (isostatic) with respect to $\ell^1$ or $\ell^\infty$ distance…

Metric Geometry · Mathematics 2018-07-04 K. Clinch , D. Kitson

A bar-and-joint framework is a finite set of points together with specified distances between selected pairs. In rigidity theory we seek to understand when the remaining pairwise distances are also fixed. If there exists a pair of points…

Combinatorics · Mathematics 2013-08-16 Christopher Clement , Audrey Lee-St. John , Jessica Sidman

Let N be a nilpotent Lie group and let S be an invariant geometric structure on N (cf. symplectic, complex or hypercomplex). We define a left invariant Riemannian metric on N compatible with S to be "minimal", if it minimizes the norm of…

Differential Geometry · Mathematics 2007-05-23 Jorge Lauret

We show that arbitrarily small antisymmetric perturbations of the zero function are sufficient to produce the stickiness phenomenon for planar nonlocal minimal graphs (with the same quantitative bounds obtained for the case of even…

Analysis of PDEs · Mathematics 2022-06-22 Benjamin Baronowitz , Serena Dipierro , Enrico Valdinoci