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We show that a generic framework $(G,p)$ on the cylinder is globally rigid if and only if $G$ is a complete graph on at most four vertices or $G$ is both redundantly rigid and $2$-connected. To prove the theorem we also derive a new…

Combinatorics · Mathematics 2018-10-16 Bill Jackson , Anthony Nixon

The minimal infinitesimal rigidity of bar-joint frameworks in the non-Euclidean spaces (R^2, ||.||_q) are characterised in terms of (2,2)-tight graphs. Specifically, a generically placed bar-joint framework (G,p) in the plane is minimally…

Metric Geometry · Mathematics 2017-05-17 Derek Kitson , Stephen Power

The identifiability problem arises naturally in a number of contexts in mathematics and computer science. Specific instances include local or global rigidity of graphs and unique completability of partially-filled tensors subject to rank…

Metric Geometry · Mathematics 2024-01-24 James Cruickshank , Fatemeh Mohammadi , Anthony Nixon , Shin-ichi Tanigawa

We consider here 6-regular plane graphs whose faces have size 1, 2 or 3. In Section 2 a practical enumeration method is given that allowed us to enumerate them up to 53 vertices. Subsequently, in Section 3 we enumerate all possible symmetry…

Combinatorics · Mathematics 2010-07-28 Michel Deza , Mathieu Dutour Sikiric

There have been rapid developments in model-based clustering of graphs, also known as block modelling, over the last ten years or so. We review different approaches and extensions proposed for different aspects in this area, such as the…

Machine Learning · Statistics 2020-01-01 Clement Lee , Darren J Wilkinson

This paper concerns models and convergence principles for dealing with stochasticity in a wide range of algorithms arising in nonlinear analysis and optimization in Hilbert spaces. It proposes a flexible geometric framework within which…

Optimization and Control · Mathematics 2026-02-17 Patrick L. Combettes , Javier I. Madariaga

We prove a strong non-structure theorem for a class of metric structures with an unstable pair of formulae. As a consequence, we show that weak categoricity (that is, categoricity up to isomorphisms and not isometries) implies several…

Logic · Mathematics 2019-08-20 Saharon Shelah , Alexander Usvyatsov

We present a general approach to the bifurcation analysis of elastic frameworks with symmetry. While group-theoretic methods for bifurcation problems with symmetry are well known, their actual implementation in the context of elastic…

Applied Physics · Physics 2023-02-15 Christelle J. Combescure , Timothy J. Healey , Jay Treacy

We study the properties of finite graphs in which the ball of radius $r$ around each vertex induces a graph isomorphic to some fixed graph $F$. This is a natural extension of the study of regular graphs, and of the study of graphs of…

Combinatorics · Mathematics 2016-12-21 Itai Benjamini , David Ellis

The Constraint Satisfaction Problem (CSP) has been intensively studied in many areas of computer science and mathematics. The approach to the CSP based on tools from universal algebra turned out to be the most successful one to study the…

Logic · Mathematics 2025-01-16 Andrei A. Bulatov

We prove rigidity for hypersurfaces with boundary in the unit $(n+1)$-sphere with scalar curvature bounded below by $n(n-1)$. Under appropriate boundary conditions, the hypersurfaces are shown to be part of the equatorial spheres. The lower…

Differential Geometry · Mathematics 2016-12-28 Lan-Hsuan Huang , Damin Wu

We study the rigidity of body-and-cad frameworks which capture the majority of the geometric constraints used in 3D mechanical engineering CAD software. We present a combinatorial characterization of the generic minimal rigidity of a subset…

Discrete Mathematics · Computer Science 2012-10-19 Audrey Lee-St. John , Jessica Sidman

We identify the restricted class of attainable effective deformations in a model of reinforced composites with parallel, long, and fully rigid fibers embedded in an elastic body. In mathematical terms, we characterize the weak limits of…

Analysis of PDEs · Mathematics 2021-05-11 Dominik Engl , Carolin Kreisbeck , Antonella Ritorto

A 2-dimensional point-line framework is a collection of points and lines in the plane which are linked by pairwise constraints that fix some angles between pairs of lines and also some point-line and point-point distances. It is rigid if…

Metric Geometry · Mathematics 2016-05-26 Bill Jackson , J. C. Owen

This paper proposes a unified approach for dynamic modeling and simulations of general tensegrity structures with rigid bars and rigid bodies of arbitrary shapes. The natural coordinates are adopted as a non-minimal description in terms of…

Computational Engineering, Finance, and Science · Computer Science 2024-08-30 Jiahui Luo , Xiaoming Xu , Zhigang Wu , Shunan Wu

A 2-dimensional direction-length framework is a collection of points in the plane which are linked by pairwise constraints that fix the direction or length of the line segments joining certain pairs of points. We represent it as a pair…

Combinatorics · Mathematics 2016-07-05 Katie Clinch , Bill Jackson , Peter Keevash

The fundamental group of a closed irreducible 3-dimensional manifold has the Rapid Decay property if and only if it is not virtually Sol. This is proved by studying distortion of length functions in graphs of groups, and the stability of…

Group Theory · Mathematics 2024-06-11 Indira Chatterji , François Gautero

In this paper we study the property of generic global rigidity for frameworks of graphs embedded in d-dimensional complex space and in a d-dimensional pseudo-Euclidean space ($R^d$ with a metric of indefinite signature). We show that a…

Metric Geometry · Mathematics 2017-08-29 Steven J. Gortler , Dylan P. Thurston

A string graph is the intersection graph of curves in the plane. Kratochv\'il previously showed the existence of infinitely many obstacles: graphs that are not string graphs but for which any edge contraction or vertex deletion produces a…

Combinatorics · Mathematics 2025-09-03 Maria Chudnovsky , David Eppstein , David Fischer

We introduce the notion of graphical discreteness to group theory. A finitely generated group is graphically discrete if whenever it acts geometrically on a locally finite graph, the automorphism group of the graph is compact-by-discrete.…

Group Theory · Mathematics 2025-11-20 Alex Margolis , Sam Shepherd , Emily Stark , Daniel Woodhouse