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Related papers: Bounding the density of spherical polygon packings

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This work investigates dense packings of congruent hard infinitesimally--thin circular arcs in the two-dimensional Euclidean space. It focuses on those denotable as major whose subtended angle $\theta \in \left ( \pi, 2\pi \right ]$.…

Soft Condensed Matter · Physics 2020-10-28 Juan Pedro Ramírez González , Giorgio Cinacchi

Optimal packing of spheres in $\mathbb R^d$ is studied by optimization of the energy $E$ (effective conductivity) of composites with ideally conducting spherical inclusions. It is demonstrated that the minimum of $E$ over locations of…

Metric Geometry · Mathematics 2014-12-25 Vladimir Mityushev

Let $P$ be a set of $n$ points in the plane. We consider a variation of the classical Erd\H{o}s-Szekeres problem, presenting efficient algorithms with $O(n^3)$ running time and $O(n^2)$ space complexity that compute: (1) A subset $S$ of $P$…

Computational Geometry · Computer Science 2024-12-18 Hernán González-Aguilar , David Orden , Pablo Pérez-Lantero , David Rappaport , Carlos Seara , Javier Tejel , Jorge Urrutia

We compute the spectra of the adjacency matrices of the semi-regular polytopes. A few different techniques are employed: the most sophisticated, which relates the 1-skeleton of the polytope to a Cayley graph, is based on methods akin to…

Combinatorics · Mathematics 2007-05-23 Nicolau C. Saldanha , Carlos Tomei

The densest binary sphere packings have historically been very difficult to determine. The only rigorously known packings in the alpha-x plane of sphere radius ratio alpha and relative concentration x are at the Kepler limit alpha = 1,…

Statistical Mechanics · Physics 2015-05-30 Adam B. Hopkins , Yang Jiao , Frank H. Stillinger , Salvatore Torquato

We consider the following geometric optimization problem: find a convex polygon of maximum area contained in a given simple polygon $P$ with $n$ vertices. We give a randomized near-linear-time $(1-\varepsilon)$-approximation algorithm for…

Computational Geometry · Computer Science 2017-10-17 Sergio Cabello , Josef Cibulka , Jan Kynčl , Maria Saumell , Pavel Valtr

We prove upper bounds on the graph diameters of polytopes in two settings. The first is a worst-case bound for polytopes defined by integer constraints in terms of the height of the integers and certain subdeterminants of the constraint…

Combinatorics · Mathematics 2022-09-16 Hariharan Narayanan , Rikhav Shah , Nikhil Srivastava

The present paper aims to solve some problems proposed by Lassak about the reduced spherical polygons. The main result is to show that the regular spherical n-gon has the minimal perimeter among all reduced spherical polygons of fixed…

Metric Geometry · Mathematics 2022-04-14 Cen Liu , Yanxun Chang

This is the sixth in a series of papers giving a proof of the Kepler conjecture, which asserts that the density of a packing of congruent spheres in three dimensions is never greater than $\pi/\sqrt{18}\approx 0.74048...$. This is the…

Metric Geometry · Mathematics 2007-05-23 Thomas C. Hales

In 2009, Roeglin and Teng showed that the smoothed number of Pareto optimal solutions of linear multi-criteria optimization problems is polynomially bounded in the number $n$ of variables and the maximum density $\phi$ of the semi-random…

Data Structures and Algorithms · Computer Science 2015-03-17 Tobias Brunsch , Heiko Roeglin

We consider a class of nonsmooth and nonconvex optimization problems over the Stiefel manifold where the objective function is the summation of a nonconvex smooth function and a nonsmooth Lipschitz continuous convex function composed with…

Optimization and Control · Mathematics 2023-03-28 Jinlai Zhu , Jianfeng Huang , Lihua Yang , Qia Li

We establish that the optimal bound for the size of the smallest integral solution of the Oppenheim Diophantine approximation problem $\abs{Q(x)-\xi}< \epsilon$ for a generic ternary form $Q$ is $\abs{x}\ll \epsilon^{-1}$. We also establish…

Number Theory · Mathematics 2018-01-04 Anish Ghosh , Alexander Gorodnik , Amos Nevo

We define three-point bounds for sphere packing that refine the linear programming bound, and we compute these bounds numerically using semidefinite programming by choosing a truncation radius for the three-point function. As a result, we…

Metric Geometry · Mathematics 2022-07-01 Henry Cohn , David de Laat , Andrew Salmon

Exploiting the relationship between 4-dimensional toric and semitoric integrable systems with Delzant and semitoric polygons, respectively, we develop techniques to compute certain equivariant packing densities and equivariant capacities of…

Symplectic Geometry · Mathematics 2023-10-31 Yu Du , Gabriel Kosmacher , Yichen Liu , Jeff Massman , Joseph Palmer , Timothy Thieme , Jerry Wu , Zheyu Zhang

The packing of hard spheres (HS) of diameter $\sigma$ in a cylinder has been used to model experimental systems, such as fullerenes in nanotubes and colloidal wire assembly. Finding the densest packings of HS under this type of confinement,…

Soft Condensed Matter · Physics 2016-02-24 Lin Fu , William Steinhardt , Hao Zhao , Joshua E. S. Socolar , Patrick Charbonneau

We study the relationship between unit-distance representations and Lovasz theta number of graphs, originally established by Lovasz. We derive and prove min-max theorems. This framework allows us to derive a weighted version of the…

Optimization and Control · Mathematics 2018-01-30 Marcel K. de Carli Silva , Levent Tunçel

We study the optimal packing of short, hard spherocylinders confined to lie tangential to a spherical surface, using simulated annealing and molecular dynamics simulations. For clusters of up to twelve particles, we map out the changes in…

Soft Condensed Matter · Physics 2016-05-25 Frank Smallenburg , Hartmut Löwen

We present the first systematic algorithm to estimate the maximum packing density of spheres when the grain sizes are drawn from an arbitrary size distribution. With an Apollonian filling rule, we implement our technique for disks in 2d and…

Statistical Mechanics · Physics 2012-01-05 Saulo D. S. Reis , Nuno A. M. Araújo , José S. Andrade , Hans J. Herrmann

We study the optimization of the positive principal eigenvalue of an indefinite weighted problem, associated with the Neumann Laplacian in a box $\Omega\subset\mathbb{R}^N$, which arises in the investigation of the survival threshold in…

Analysis of PDEs · Mathematics 2019-09-26 Dario Mazzoleni , Benedetta Pellacci , Gianmaria Verzini

We show that every packing of congruent regular pentagons in the Euclidean plane has density at most $(5-\sqrt5)/3$, which is about 0.92. More specifically, this article proves the pentagonal ice-ray conjecture of Henley (1986), and…

Metric Geometry · Mathematics 2016-09-14 Thomas Hales , Wöden Kusner
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