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Related papers: The kissing number in four dimensions

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In this paper, we give some new lower bounds for the kissing number of $\ell_p$-spheres. These results improve the previous work due to Xu (2007). Our method is based on coding theory.

Metric Geometry · Mathematics 2022-07-21 Chengfei Xie , Gennian Ge

This paper provides upper and lower bounds on the kissing number of congruent radius $r > 0$ spheres in hyperbolic $\mathbb{H}^n$ and spherical $\mathbb{S}^n$ spaces, for $n\geq 2$. For that purpose, the kissing number is replaced by the…

Combinatorics · Mathematics 2021-05-27 Maria Dostert , Alexander Kolpakov

We prove a lower bound of $\Omega (d^{3/2} \cdot (2/\sqrt{3})^d)$ on the kissing number in dimension $d$. This improves the classical lower bound of Chabauty, Shannon, and Wyner by a linear factor in the dimension. We obtain a similar…

Metric Geometry · Mathematics 2018-07-10 Matthew Jenssen , Felix Joos , Will Perkins

We prove that the $D_4$ root system (the set of vertices of the regular $24$-cell) is the unique optimal kissing configuration in $\mathbb R^4$, and is an optimal spherical code. For this, we use semidefinite programming to compute an exact…

Metric Geometry · Mathematics 2024-05-28 David de Laat , Nando M. Leijenhorst , Willem H. H. de Muinck Keizer

The thirteen spheres problem is asking if 13 equal size nonoverlapping spheres in three dimensions can touch another sphere of the same size. This problem was the subject of the famous discussion between Isaac Newton and David Gregory in…

Metric Geometry · Mathematics 2015-03-13 Oleg Musin , Alexey Tarasov

L\'{a}szl\'{o} Fejes T\'{o}th and Alad\'{a}r Heppes proposed the following generalization of the kissing number problem. Given a ball in $\mathbb{R}^d$, consider a family of balls touching it, and another family of balls touching the first…

Metric Geometry · Mathematics 2022-10-19 Alexander Golovanov

An elementary construction using binary codes gives new record kissing numbers in dimensions from 32 to 128.

Combinatorics · Mathematics 2007-07-16 Yves Edel , E. M. Rains , N. J. A. Sloane

In discrete geometry, the contact number of a given finite number of non-overlapping spheres was introduced as a generalization of Newton's kissing number. This notion has not only led to interesting mathematics, but has also found…

Metric Geometry · Mathematics 2020-02-12 Karoly Bezdek , Muhammad A. Khan

The so-called {\it kissing number} for hyperbolic surfaces is the maximum number of homotopically distinct systoles a surface of given genus $g$ can have. These numbers, first studied (and named) by Schmutz Schaller by analogy with lattice…

Geometric Topology · Mathematics 2014-02-26 Hugo Parlier

We prove that the kissing number in 19 dimensions is at least 11948, improving the bound of Cohn and Li by 256. By the odd-sign construction of Cohn and Li, it is enough to find a binary code of length 19 and minimum distance 5 inside the…

Metric Geometry · Mathematics 2026-03-23 Boon Suan Ho

The Koebe circle packing theorem states that every finite planar graph can be realized as the nerve of a packing of (non-congruent) circles in R^3. We investigate the average kissing number of finite packings of non-congruent spheres in R^3…

Metric Geometry · Mathematics 2016-09-06 Greg Kuperberg , Oded Schramm

This paper provides upper and lower bounds on the kissing number of congruent radius $r > 0$ spheres in $\mathbb{H}^n$, for $n\geq 2$. For that purpose, the kissing number is replaced by the kissing function $\kappa(n, r)$ which depends on…

Metric Geometry · Mathematics 2020-03-10 Maria Dostert , Alexander Kolpakov

We present an extension of known semidefinite and linear programming upper bounds for spherical codes. We apply the main result for the distance distribution of a spherical code and show that this method can work effectively In particular,…

Optimization and Control · Mathematics 2023-10-03 Oleg R. Musin

The average kissing number of $\mathbb{R}^n$ is the supremum of the average degrees of contact graphs of packings of finitely many balls (of any radii) in $\mathbb{R}^n$. We provide an upper bound for the average kissing number based on…

Metric Geometry · Mathematics 2020-03-27 Maria Dostert , Alexander Kolpakov , Fernando Mário de Oliveira Filho

The best previous lower bounds for kissing numbers in dimensions 25 through 31 were constructed using a set $S$ with $|S| = 480$ of minimal vectors of the Leech Lattice, $\Lambda_{24}$, such that $\langle x, y \rangle \leq 1$ for any…

Metric Geometry · Mathematics 2017-09-12 Kenz Kallal , Tomoka Kan , Eric Wang

This paper investigates the behaviour of the kissing number $\kappa(n, r)$ of congruent radius $r > 0$ spheres in $\mathbb{S}^n$, for $n\geq 2$. Such a quantity depends on the radius $r$, and we plot the approximate graph of $\kappa(n, r)$…

Metric Geometry · Mathematics 2020-03-10 Maria Dostert , Alexander Kolpakov

Pfender \textit{[J. Combin. Theory Ser. A, 2007]} provided a one-line proof for a variant of the Delsarte-Goethals-Seidel-Kabatianskii-Levenshtein upper bound for spherical codes, which offers an upper bound for the celebrated…

Functional Analysis · Mathematics 2025-07-17 K. Mahesh Krishna

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 prove upper bounds on the average kissing number $k(\mathcal{P})$ and contact number $C(\mathcal{P})$ of an arbitrary finite non-congruent sphere packing $\mathcal{P}$, and prove an upper bound on the packing density…

Metric Geometry · Mathematics 2015-10-05 Samuel Reid

We introduce the notion of p-adic spherical codes (in particular, p-adic kissing number problem). We show that the one-line proof for a variant of the Delsarte-Goethals-Seidel-Kabatianskii-Levenshtein upper bound for spherical codes,…

Number Theory · Mathematics 2025-03-10 K. Mahesh Krishna