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Related papers: Contact numbers for sphere packings

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We prove the existence of exotic but homotopically trivial contact structures on spheres of dimension 8k-1. Together with previous results of Eliashberg and the second author this establishes the existence of such structures on all…

Symplectic Geometry · Mathematics 2007-05-23 Fan Ding , Hansjörg Geiges

We consider plumbings of symplectic disk bundles over spheres admitting concave contact boundary, with the goal of understanding the geometric properties of the boundary contact structure in terms of the data of the plumbing. We focus on…

Symplectic Geometry · Mathematics 2025-01-16 Aleksandra Marinković , Jo Nelson , Ana Rechtman , Laura Starkston , Shira Tanny , Luya Wang

We propose a new geometrical model of matter, in which neutral atoms are modelled by compact, complex algebraic surfaces. Proton and neutron numbers are determined by a surface's Chern numbers. Equivalently, they are determined by…

High Energy Physics - Theory · Physics 2016-09-12 M. F. Atiyah , N. S. Manton

We analyze Sz\"oll\H{o}si's recent construction of a conjecturally optimal five-dimensional kissing configuration and produce a new such configuration, the fourth to be discovered. We construct five-dimensional sphere packings from these…

Metric Geometry · Mathematics 2026-03-05 Henry Cohn , Isaac Rajagopal

A universality ansatz for the contact values of a multicomponent mixture of additive hard spheres is used to propose new formulae for the case of disparate-size binary mixtures. A comparison with simulation data and with a recent proposal…

Soft Condensed Matter · Physics 2009-05-22 A. Santos , S. B. Yuste , M. López de Haro , M. Alawneh , D. Henderson

An important application of distance geometry to biochemistry studies the embeddings of the vertices of a weighted graph in the three-dimensional Euclidean space such that the edge weights are equal to the Euclidean distances between…

Computational Geometry · Computer Science 2011-03-08 Leo Liberti , Carlile Lavor , Benoit Masson , Antonio Mucherino

This is a survey of contact homology and its applications to the study of contact manifolds. It is a small tribute to Yasha Eliashberg's huge generosity with his countless explanations of his deep mathematical insights all along his career.…

Symplectic Geometry · Mathematics 2025-04-25 Frédéric Bourgeois

A family of potential-density pairs that represent spherical shells with finite thickness is obtained from the superposition of spheres with finite radii. Other families of shells with infinite thickness with a central hole are obtained by…

General Relativity and Quantum Cosmology · Physics 2010-11-01 D. Vogt , P. S. Letelier

A problem of Erd\H{o}s (Amer. Math. Monthly 52: 494-498, 1945) and a theorem of Fejes T\'oth and Fejes T\'oth (Acta Math. Acad. Sci. Hungar. 24: 229-232, 1973) initiated the study of non-separable arrangements of convex bodies and the…

Metric Geometry · Mathematics 2025-01-14 Károly Bezdek , Zsolt Lángi

We consider bounds on codes in spherical caps and related problems in geometry and coding theory. An extension of the Delsarte method is presented that relates upper bounds on the size of spherical codes to upper bounds on codes in caps.…

Metric Geometry · Mathematics 2007-07-16 Alexander Barg , Oleg R. Musin

We show that an analogy between crowding in fluid and jammed phases of hard spheres captures the density dependence of the kissing number for a family of numerically generated jammed states. We extend this analogy to jams of mixtures of…

Any space-filling packing of spheres can be cut by a plane to obtain a space-filling packing of disks. Here, we deal with space-filling packings generated using inversive geometry leading to exactly self-similar fractal packings. First, we…

Soft Condensed Matter · Physics 2016-09-14 D. V. Stäger , H. J. Herrmann

Two spheres with centers $p$ and $q$ and signed radii $r$ and $s$ are said to be in contact if $|p-q|^2 = (r-s)^2$. Using Lie's line-sphere correspondence, we show that if $F$ is a field in which $-1$ is not a square, then there is an…

Combinatorics · Mathematics 2023-08-24 Joshua Zahl

k-Contact geometry is a generalisation of contact geometry to analyse field theories. We develop an approach to k-contact geometry based on distributions that are distributionally maximally non-integrable and admit, locally, k commuting…

Differential Geometry · Mathematics 2025-02-06 Javier de Lucas , Xavier Rivas , Tomasz Sobczak

Sphere packings are essential to the development of physical models for powders, composite materials, and the atomic structure of the liquid state. There is a strong scientific need to be able to assess the fit of packing models to data,…

Methodology · Statistics 2009-10-31 Jeffrey Picka

Physical strands or sheets that can be modelled as curves or surfaces embedded in three dimensions are ubiquitous in nature, and are of fundamental importance in mathematics, physics, biology and engineering. Often the physical…

Statistical Mechanics · Physics 2007-05-23 J. R. Banavar , O. Gonzalez , J. H. Maddocks , A. Maritan

The original Thomson problem of "spherical crystallography" seeks the ground state of electron shells interacting via the Coulomb potential; however one can also study crystalline ground states of particles interacting with other…

Soft Condensed Matter · Physics 2009-11-11 Mark J. Bowick , Angelo Cacciuto , David R. Nelson , Alex Travesset

In this paper we develop some combinatorial models for continuous spaces. In this spirit we study the approximations of continuous spaces by graphs, molecular spaces and coordinate matrices. We define the dimension on a discrete space by…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Alexander V. Evako

We give examples of tight high dimensional contact manifolds admitting a contactomorphism whose powers are all smoothly isotopic but not contact-isotopic to the identity. This is a generalization of an observation in dimension 3 by Gompf,…

Symplectic Geometry · Mathematics 2021-07-08 Fabio Gironella

We develop an algorithm to construct new self-similar space-filling packings of spheres. Each topologically different configuration is characterized by its own fractal dimension. We also find the first bi-cromatic packing known up to now.

Condensed Matter · Physics 2007-05-23 Reza Mahmoodi Baram , Hans J. Herrmann