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Related papers: Upper Bounds for Non-Congruent Sphere Packings

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We study a random partial covering model on the $(d-1)$-dimensional unit sphere, where $N$ spherical caps are placed independently and uniformly at random, each covering a surface fraction of $1/N$. This model provides a continuous…

Probability · Mathematics 2026-04-10 Steven Hoehner , Christoph Thäle

We prove upper bounds on the rate, called "mixing rate", at which the von Neumann entropy of the expected density operator of a given ensemble of states changes under non-local unitary evolution. For an ensemble consisting of two states,…

Quantum Physics · Physics 2013-11-06 Elliott H. Lieb , Anna Vershynina

Given a sample from some unknown continuous density $f:\mathbb{R}\to\mathbb{R}$, we construct adaptive confidence bands that are honest for all densities in a "generic" subset of the union of $t$-H\"older balls, $0<t\le r$, where $r$ is a…

Statistics Theory · Mathematics 2010-02-26 Evarist Giné , Richard Nickl

At finite temperature (T) there is a link with general relativity and hydrodynamics that leads to a lower bound for the ratio of shear viscosity and entropy density (\eta/s). We find that the bound is saturated in the simple model for quark…

High Energy Physics - Phenomenology · Physics 2007-06-13 Sibasish Laha , Taparati Gangopadhyay , Manjari Bagchi , Mira Dey , Jishnu Dey , Monika Sinha , Subharthi Ray

In this paper we provide asymptotic upper bounds on the complexity in two (closely related) situations. We confirm for the total doubling coverings and not only for the chains the expected bounds of the form $$ \kappa({\mathcal U}) \le…

Classical Analysis and ODEs · Mathematics 2019-03-12 Raf Cluckers , Omer Friedland , Yosef Yomdin

We give a new upper bound $K_+$ on the number of totally elastic collisions of $n$ hard spheres with equal radii and equal masses in $R^d$. Our bound satisfies $\log K_+ \leq c(d) n \log n$.

Dynamical Systems · Mathematics 2022-01-19 Krzysztof Burdzy

The note shows an easy way to improve E.H. Smith's packing density bound in $\mathbb{R}^3$ from $0.53835...$ to $0.54755...$ .

Metric Geometry · Mathematics 2023-01-02 Arkadiy Aliev

A sphere packing bound (SPB) with a prefactor that is polynomial in the block length $n$ is established for codes on a length $n$ product channel $W_{[1,n]}$ assuming that the maximum order $1/2$ Renyi capacity among the component channels,…

Information Theory · Computer Science 2019-08-27 Baris Nakiboglu

In the packing-constrained point covering problem, PC^2, one seeks configurations of points in the plane that cannot all be covered by a packing arrangement of unit disks. We consider in particular the problem of finding the minimum number…

Metric Geometry · Mathematics 2011-01-19 Veit Elser

In this paper we study the blow-ups of the singular points in the boundary of a minimizing cluster lying in the interface of more than two chambers. We establish a sharp lower bound for the perimeter density at those points and we prove…

Analysis of PDEs · Mathematics 2018-01-30 Jonas Hirsch , Michele Marini

The mean-field limit of interacting diffusions without exchangeability, caused by weighted interactions and non-i.i.d. initial values, are investigated. The weights could be signed and unbounded. The result applies to a large class of…

Probability · Mathematics 2026-01-19 Zhenfu Wang , Xianliang Zhao , Rongchan Zhu

We propose upper and lower bounds on the maximum success probability for discriminating given quantum states. The proposed upper bound is obtained from a suboptimal solution to the dual problem of the corresponding optimal state…

Quantum Physics · Physics 2018-01-12 Kenji Nakahira , Tsuyoshi Sasaki Usuda , Kentaro Kato

We study properties of the innermost photonsphere in the regular compact star background. We take the traceless energy-momentum tensor and dominant energy conditions. In the regular compact star background, we analytically obtain an upper…

General Relativity and Quantum Cosmology · Physics 2024-02-27 Guohua Liu , Yan Peng

We show that there exists a lattice covering of $\mathbb{R}^n$ by Eucledian spheres of equal radius with density $O\big(n \ln^{\beta} n \big)$ as $n\to\infty$, where \begin{align*} \beta := \frac{1}{2} \log_2 \left(\frac{8 \pi…

Metric Geometry · Mathematics 2025-08-11 Jun Gao , Xizhi Liu , Oleg Pikhurko , Shumin Sun

We derive a sphere-packing error exponent for coded transmission over discrete memoryless channels with a fixed decoding metric. By studying the error probability of the code over an auxiliary channel, we find a lower bound to the…

Information Theory · Computer Science 2022-12-29 Ehsan Asadi Kangarshahi , Albert Guillén i Fàbregas

Given a sphere of any radius $r$ in an $n$-dimensional Euclidean space, we study the coverings of this sphere with solid spheres of radius one. Our goal is to design a covering of the lowest covering density, which defines the average…

Metric Geometry · Mathematics 2018-05-22 Ilya Dumer

We find sharp absolute constants $C_1$ and $C_2$ with the following property: every well-rounded lattice of rank 3 in a Euclidean space has a minimal basis so that the solid angle spanned by these basis vectors lies in the interval…

Metric Geometry · Mathematics 2010-11-29 Lenny Fukshansky , Sinai Robins

Packing problems, which ask how to arrange a collection of objects in space to meet certain criteria, are important in a great many physical and biological systems, where geometrical arrangements at small scales control behaviour at larger…

Soft Condensed Matter · Physics 2016-05-23 Miranda C. Holmes-Cerfon

In this paper, upper bounds for the densities of the densest translative tetrahedron packings and the densest translative cubooctahedron packings are obtained.

Metric Geometry · Mathematics 2012-11-14 Chuanming Zong

We show that a graph with $n$ vertices and vertex cover of size $k$ has at most $4^k + n$ potential maximal cliques. We also show that for each positive integer $k$, there exists a graph with vertex cover of size $k$, $O(k^2)$ vertices, and…

Combinatorics · Mathematics 2020-11-24 Tuukka Korhonen