English
Related papers

Related papers: Illumination of convex bodies with many symmetries

200 papers

In ["Illumination of convex bodies with many symmetries", Mathematika 63 (2017)], Tikhomirov verified the Hadwiger-Boltyanski Illumination Conjecture for the class of 1-symmetric convex bodies of sufficiently large dimension. We propose an…

Metric Geometry · Mathematics 2024-07-16 Wen Rui Sun , Beatrice-Helen Vritsiou

It was conjectured by Levi, Hadwiger, Gohberg and Markus that the boundary of any convex body in ${\mathbb R}^n$ can be illuminated by at most $2^n$ light sources, and, moreover, $2^n-1$ light sources suffice unless the body is a…

Metric Geometry · Mathematics 2017-10-17 Galyna Livshyts , Konstantin Tikhomirov

We settle the Hadwiger-Boltyanski Illumination Conjecture for all 1-unconditional convex bodies in ${\mathbb R}^3$ and in ${\mathbb R}^4$. Moreover, we settle the conjecture for those higher-dimensional 1-unconditional convex bodies which…

Metric Geometry · Mathematics 2025-08-06 Wen Rui Sun , Beatrice-Helen Vritsiou

The illumination conjecture asserts that any convex body in $n$-dimensional Euclidean space can be illuminated by at most $2^n$ external light sources or parallel beams of light. Despite recent progress on the illumination conjecture, it…

Metric Geometry · Mathematics 2026-02-05 Andrii Arman , Jaskaran Singh Kaire , Andriy Prymak

The illumination conjecture is a classical open problem in convex and discrete geometry, asserting that every compact convex body~$K$ in $\mathbb R^n$ can be illuminated by a set of no more than $2^n$ points. If $K$ has smooth boundary, it…

Metric Geometry · Mathematics 2025-03-31 Lenny Fukshansky

The Illumination Problem may be phrased as the problem of covering a convex body in Euclidean $n$-space by a minimum number of translates of its interior. By a probabilistic argument, we show that, arbitrarily close to the Euclidean ball,…

Metric Geometry · Mathematics 2016-02-24 Márton Naszódi

Hadwiger's covering conjecture is that every $n$-dimensional convex body can be covered by at most $2^n$ of its smaller positive homothetic copies, with $2^n$ copies required only for affine images of $n$-cube. Convex hull of a ball and an…

Metric Geometry · Mathematics 2025-12-16 Andrii Arman , Jaskaran Singh Kaire , Andriy Prymak

The illumination number $I(K)$ of a convex body $K$ in Euclidean space $\mathbb{E}^d$ is the smallest number of directions that completely illuminate the boundary of a convex body. A cap body $K_c$ of a ball is the convex hull of a…

Metric Geometry · Mathematics 2026-05-01 Ilya Ivanov , Cameron Strachan

The convex hull of a ball with an exterior point is called a spike (or cap). A union of finitely many spikes of a ball is called a spiky ball. If a spiky ball is convex, then we call it a cap body. In this note we upper bound the…

Metric Geometry · Mathematics 2022-12-16 Károly Bezdek , Ilya Ivanov , Cameron Strachan

Let $H_n$ be the minimal number such that any $n$-dimensional convex body can be covered by $H_n$ translates of interior of that body. Similarly $H_n^s$ is the corresponding quantity for symmetric bodies. It is possible to define $H_n$ and…

Metric Geometry · Mathematics 2024-04-02 Andrii Arman , Andriy Bondarenko , Andriy Prymak

Covering numbers of convex bodies based on homothetical copies and related illumination numbers are well-known in combinatorial geometry and, for example, related to Hadwiger's famous covering problem. Similar numbers can be defined by…

Metric Geometry · Mathematics 2013-08-06 Horst Martini , Christian Richter , Margarita Spirova

The X-ray numbers of some classes of convex bodies are investigated. In particular, we give a proof of the X-ray Conjecture as well as of the Illumination Conjecture for almost smooth convex bodies of any dimension and for convex bodies of…

Metric Geometry · Mathematics 2011-09-29 Karoly Bezdek , Gyorgy Kiss

At a first glance, the problem of illuminating the boundary of a convex body by external light sources and the problem of covering a convex body by its smaller positive homothetic copies appear to be quite different. They are in fact two…

Metric Geometry · Mathematics 2018-11-06 Karoly Bezdek , Muhammad A. Khan

We present a probabilistic model of illuminating a convex body by independently distributed light sources. In addition to recovering C.A. Rogers' upper bounds for the illumination number, we improve previous estimates of J. Januszewski and…

Metric Geometry · Mathematics 2016-06-30 Galyna Livshyts , Konstantin Tikhomirov

A subset of the d-dimensional Euclidean space having nonempty interior is called a spindle convex body if it is the intersection of (finitely or infinitely many) congruent d-dimensional closed balls. The spindle convex body is called a…

Metric Geometry · Mathematics 2013-02-13 Karoly Bezdek

The paper is devoted to coverings by translative homothets and illuminations of convex bodies. For a given positive number $\alpha$ and a convex body $B$, $g_{\alpha}(B)$ is the infimum of $\alpha$-powers of finitely many homothety…

Metric Geometry · Mathematics 2021-07-21 Alexey Glazyrin

The concept of illumination bodies studied in convex geometry is used to amend the halfspace depth for multivariate data. The proposed notion of illumination enables finer resolution of the sample points, naturally breaks ties in the…

Statistics Theory · Mathematics 2021-05-28 Stanislav Nagy , Jiří Dvořák

We show that there exist convex bodies of constant width in $\mathbb{E}^n$ with illumination number at least $(\cos(\pi/14)+o(1))^{-n}$, answering a question by G. Kalai. Furthermore, we prove the existence of finite sets of diameter $1$ in…

Metric Geometry · Mathematics 2024-06-27 Andrii Arman , Andriy Bondarenko , Andriy Prymak

For a given $\lambda >0$, a convex body in $\mathbb R^n$ is $\lambda$-convex if it is the intersection of (finitely or infinitely many) balls of radius $1/\lambda$. In this note, we show that among all $\lambda$-convex bodies in $\mathbb…

Metric Geometry · Mathematics 2025-11-18 Kostiantyn Drach , Kateryna Tatarko

We formulate a complex analog of the celebrated Levi-Hadwiger-Boltyanski illumination (or covering) conjecture for complex convex bodies in C^n, as well as its (non-comparable) fractional version. A key element in posing these problems is…

Metric Geometry · Mathematics 2024-10-17 Liran Rotem , Alon Schejter , Boaz A. Slomka
‹ Prev 1 2 3 10 Next ›