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Related papers: Infinitesimal Rigidity of Symmetric Frameworks

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This paper introduces new structures called conic frameworks and their rigidity. They are composed by agents and a set of directed constraints between pairs of agents. When the structure cannot be flexed while preserving the constraints, it…

Combinatorics · Mathematics 2022-07-08 Colin Cros , Pierre-Olivier Amblard , Christophe Prieur , Jean-François Da Rocha

We present necessary and sufficient conditions for the generic rigidity of body-bar frameworks on the three-dimensional fixed torus. These frameworks correspond to infinite periodic body-bar frameworks in $\mathbb{R}^3$ with a fixed…

Metric Geometry · Mathematics 2014-03-05 Elissa Ross

Consider a collection of points in the plane and the sets of slopes or directions of the lines between pairs of points. It is known that the algebraic matroid on the set of direction constraints between the points is equivalent to the…

Combinatorics · Mathematics 2026-04-27 Sean Dewar , Georg Grasegger , Anthony Nixon , Zvi Rosen , William Sims , Meera Sitharam , David Urizar

We show the existence of infinitesimally rigid bipartite unit-bar frameworks in $\mathbb{R}^d$. We also construct unit-bar frameworks with girth up to 12 that are infinitesimally rigid in the plane. This answers problems proposed by…

Combinatorics · Mathematics 2018-08-14 Jozsef Solymosi , Ethan White

Necessary and sufficient conditions are obtained for the infinitesimal rigidity of braced grids in the plane with respect to non-Euclidean norms. Component rectangles of the grid may carry 0, 1 or 2 diagonal braces, and the combinatorial…

Metric Geometry · Mathematics 2020-09-24 Stephen Power

Combinatorial rigidity theory seeks to describe the rigidity or flexibility of bar-joint frameworks in R^d in terms of the structure of the underlying graph G. The goal of this article is to broaden the foundations of combinatorial rigidity…

Combinatorics · Mathematics 2011-10-05 Mike Develin , Jeremy L. Martin , Victor Reiner

A bar framework (G,p) in dimension r is a graph G whose vertices are points p^1,...,p^n in R^r and whose edges are line segments between pairs of these points. Two frameworks (G,p) and (G,q) are equivalent if each edge of (G,p) has the same…

Metric Geometry · Mathematics 2015-04-03 A. Y. Alfakih

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

A framework is a graph and a map from its vertices to E^d (for some d). A framework is universally rigid if any framework in any dimension with the same graph and edge lengths is a Euclidean image of it. We show that a generic universally…

Metric Geometry · Mathematics 2014-06-17 Steven J. Gortler , Dylan P. Thurston

We explore the rigidity of generic frameworks in 3-dimensions whose underlying graph is close to being planar. Specifically we consider apex graphs, edge-apex graphs and their variants and prove independence results in the generic…

Combinatorics · Mathematics 2024-02-28 Sean Dewar , Georg Grasegger , Eleftherios Kastis , Anthony Nixon , Brigitte Servatius

We establish a connection between problems studied in rigidity theory and matroids arising from linear algebraic constructions like tensor products and symmetric products. A special case of this correspondence identifies the problem of…

Combinatorics · Mathematics 2026-03-04 Joshua Brakensiek , Manik Dhar , Jiyang Gao , Sivakanth Gopi , Matt Larson

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

This paper provides a combinatorial characterisation for generic forced symmetric rigidity of bar-joint frameworks in the Euclidean plane that are symmetric with respect to the orientation-reversing wallpaper group…

Combinatorics · Mathematics 2025-02-21 Jack Esson , Eleftherios Kastis , Bernd Schulze

We review some recent results in the generic rigidity theory of planar frameworks with forced symmetry, giving a uniform treatment to the topic. We also give new combinatorial characterizations of minimally rigid periodic frameworks with…

Geometric Topology · Mathematics 2012-03-06 Justin Malestein , Louis Theran

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

We have developed a symmetry-adapted modeling procedure for molecules and crystals. By using the completeness of multipoles to express spatial and time-reversal parity-specific anisotropic distributions, we can generate systematically the…

Materials Science · Physics 2023-05-12 Hiroaki Kusunose , Rikuto Oiwa , Satoru Hayami

We provide a way of determining the infinitesimal rigidity of rod configurations realizing a rank two incidence geometry in the Euclidean plane. We model each rod with a cone over its point set and prove that the resulting geometric…

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

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

A bar-joint framework $(G,p)$ in the Euclidean space $\mathbb{E}^d$ is globally rigid if it is the unique realisation, up to rigid congruences, of $G$ in $\mathbb{E}^d$ with the edge lengths of $(G,p)$. Building on key results of…

Combinatorics · Mathematics 2022-06-16 Sean Dewar , John Hewetson , Anthony Nixon

How does one determine if a collection of bars joined by freely rotating hinges cannot be deformed without changing the length of any of the bars? In other words, how does one determine if a bar-joint graph is rigid? This question has been…

Disordered Systems and Neural Networks · Physics 2024-10-02 Kyungeun Kim , J. M. Schwarz