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Related papers: Illumination Bodies in Projective Geometries

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We carry out a systematic investigation on floating bodies in real space forms. A new unifying approach not only allows us to treat the important classical case of Euclidean space as well as the recent extension to the Euclidean unit…

Differential Geometry · Mathematics 2016-06-27 Florian Besau , Elisabeth M. Werner

We prove new Alexandrov-Fenchel type inequalities and new affine isoperimetric inequalities for mixed $p$-affine surface areas. We introduce a new class of bodies, the illumination surface bodies, and establish some of their properties. We…

Metric Geometry · Mathematics 2010-07-09 Elisabeth Werner , Deping Ye

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

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

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

In this note we introduce the problem of illumination of convex bodies in spherical spaces and solve it for a large subfamily of convex bodies. We derive from it a combinatorial version of the classical illumination problem for convex…

Metric Geometry · Mathematics 2020-10-13 Károly Bezdek , Zsolt Lángi

We study relations of some classes of $k$-convex, $k$-visible bodies in Euclidean spaces. We introduce and study \textrm{circular projections} in normed linear spaces and classes of bodies related with families of such maps, in particular,…

Metric Geometry · Mathematics 2015-12-31 V. Golubyatnikov V. Rovenski

We define floating bodies in the class of $n$-dimensional ball-convex bodies. A right derivative of volume of these floating bodies leads to a surface area measure for ball-convex bodies which we call relative affine surface area. We show…

Metric Geometry · Mathematics 2025-04-23 Carsten Schuett , Elisabeth M Werner , Diliya Yalikun

For a convex body on the Euclidean unit sphere the spherical convex floating body is introduced. The asymptotic behavior of the volume difference of a spherical convex body and its spherical floating body is investigated. This gives rise to…

Differential Geometry · Mathematics 2014-12-01 Florian Besau , Elisabeth Werner

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

We introduce floating bodies for convex, not necessarily bounded subsets of $\mathbb{R}^n$. This allows us to define floating functions for convex and log concave functions and log concave measures. We establish the asymptotic behavior of…

Functional Analysis · Mathematics 2018-08-07 Ben Li , Carsten Schuett , Elisabeth M. Werner

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

While there is extensive literature on approximation of convex bodies by inscribed or circumscribed polytopes, much less is known in the case of generally positioned polytopes. Here we give upper and lower bounds for approximation of convex…

Probability · Mathematics 2021-03-03 Steven D. Hoehner , Carsten Schuett , Elisabeth M. Werner

In convex geometry, the constructions that assign to a convex body its difference body, projection body, or volume have the following properties: They are (1) invariant under volume-preserving linear changes of coordinates; (2) continuous;…

Metric Geometry · Mathematics 2024-02-12 Jakob Henkel , Thomas Wannerer

By recasting metrical geometry in a purely algebraic setting, both Euclidean and non-Euclidean geometries can be studied over a general field with an arbitrary quadratic form. Both an affine and a projective version of this new theory are…

Metric Geometry · Mathematics 2007-05-23 Norman J. Wildberger

We introduce an alternative formalization of curved spaces in which the concept of a pointwise affine space, as defined here, replaces that of a manifold. New or modified definitions of familiar notions from differential geometry such as…

Differential Geometry · Mathematics 2025-09-09 Dan Jonsson

The aim of this paper is to investigate the differential geometry of immersed surfaces in three-dimensional normed spaces from the viewpoint of affine differential geometry. We endow the surface with a useful Riemannian metric which is…

Differential Geometry · Mathematics 2017-09-06 Vitor Balestro , Horst Martini , Ralph Teixeira

Given an affine variety X and a finite dimensional vector space of regular functions L on X, we associate a convex body to (X, L) such that its volume is responsible for the number of solutions of a generic system of functions from L. This…

Algebraic Geometry · Mathematics 2008-04-28 Kiumars Kaveh , Askold G. Khovanskii

We investigate a natural analog to Lutwak's $p$-affine surface area in $d$-dimensional spherical, hyperbolic and de Sitter space. In particular, we show that these curvature measures appear naturally as the volume derivative of floating…

Metric Geometry · Mathematics 2023-11-07 Florian Besau , Elisabeth M. Werner

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
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