English
Related papers

Related papers: An Upper Bound for Lebesgue's Covering Problem

200 papers

Lebesgue's universal covering problem is re-examined using computational methods. This leads to conjectures about the nature of the solution which if correct could provide a blueprint for a complete solution. Empirical lower bounds for the…

Metric Geometry · Mathematics 2014-02-20 Philip Gibbs

In 1914 Lebesgue defined a "universal covering" to be a convex subset of the plane that contains an isometric copy of any subset of diameter 1. His challenge of finding a universal covering with the least possible area has been addressed by…

Metric Geometry · Mathematics 2017-08-22 John C. Baez , Karine Bagdasaryan , Philip Gibbs

Universal cover in $\mathbb{E}^{n}$ is a measurable set that contains a congruent copy of any set of diameter 1. Lebesgue's universal covering problem, posed in 1914, asks for the convex set of smallest area that serves as a universal cover…

Metric Geometry · Mathematics 2025-12-04 Andrii Arman , Andriy Bondarenko , Andriy Prymak , Danylo Radchenko

In this paper we give a geometric argument for bounding the diameter of a connected compact surface (with boundary) of arbitrary codimension in Euclidean space in terms of Topping's diameter bound for closed surfaces (without boundary). The…

Differential Geometry · Mathematics 2023-01-11 Tatsuya Miura

We improve a lower bound for the smallest area of convex covers for closed unit curves from 0.0975 to 0.1, which makes it substantially closer to the current best upper bound 0.11023. We did this by considering the minimal area of convex…

Metric Geometry · Mathematics 2020-04-08 Bogdan Grechuk , Sittichoke Som-am

In this paper, we provide a lower bound for an area of the convex hull of points and a rectangle in a plane. We then apply this estimate to establish a lower bound for a universal cover problem. We showed that a convex universal cover for a…

Metric Geometry · Mathematics 2015-03-18 Tirasan Khandhawit , Dimitrios Pagonakis , Sira Sriswasdi

We combine geometric methods with numerical box search algorithm to show that the minimal area of a convex set on the plane which can cover every closed plane curve of unit length is at least 0.0975. This improves the best previous lower…

Metric Geometry · Mathematics 2019-05-02 Bogdan Grechuk , Sittichoke Som-Am

The width of a closed convex subset of Euclidean space is the distance between two parallel supporting planes. The Blaschke-Lebesgue problem consists of minimizing the volume in the class of convex sets of fixed constant width and is still…

Differential Geometry · Mathematics 2010-08-17 Henri Anciaux , Brendan Guilfoyle

The moving sofa problem, posed by L. Moser in 1966, asks for the planar shape of maximal area that can move around a right-angled corner in a hallway of unit width. It is known that a maximal area shape exists, and that its area is at least…

Metric Geometry · Mathematics 2018-10-30 Yoav Kallus , Dan Romik

In connection with an unsolved problem of Bang (1951) we give a lower bound for the sum of the base volumes of cylinders covering a d-dimensional convex body in terms of the relevant basic measures of the given convex body. As an…

Metric Geometry · Mathematics 2011-09-29 Karoly Bezdek , Alexander Litvak

We present a method to obtain upper bounds on covering numbers. As applications of this method, we reprove and generalize results of Rogers on economically covering Euclidean $n$-space with translates of a convex body, or more generally,…

Metric Geometry · Mathematics 2015-10-12 Márton Naszódi

Let $H_n$ be the minimal number of smaller homothetic copies of an $n$-dimensional convex body required to cover the whole body. Equivalently, $H_n$ can be defined via illumination of the boundary of a convex body by external light sources.…

Metric Geometry · Mathematics 2020-10-01 A. Prymak , V. Shepelska

The Heilbronn triangle problem asks for the placement of $n$ points in a unit square that maximizes the smallest area of a triangle formed by any three of those points. In $1972$, Schmidt considered a natural generalization of this problem.…

Discrete Mathematics · Computer Science 2024-05-22 Rishikesh Gajjala , Jayanth Ravi

Let $(\mathcal{X},\rho)$ be a metric space and $\lambda$ be a Borel measure on this space defined on the $\sigma$-algebra generated by open subsets of $\mathcal{X}$; this measure $\lambda$ defines volumes of Borel subsets of $\mathcal{X}$.…

Optimization and Control · Mathematics 2022-11-07 Anatoly Zhigljavsky , Jack Noonan

Often some interesting or simply curious points are left out when developing a theory. It seems that one of them is the existence of an upper bound for the fraction of area of a convex and closed plane area lying outside a circle with which…

General Mathematics · Mathematics 2007-05-23 Jose M. Pacheco

Quantitative estimates related to the classical Borsuk problem of splitting set in Euclidean space into subsets of smaller diameter are considered. For a given $k$ there is a minimal diameter of subsets at which there exists a covering with…

Metric Geometry · Mathematics 2022-10-25 Alexander Tolmachev , Dmitry Protasov , Vsevolod Voronov

This paper determines the optimal upper bound for the simultaneous packing and covering constants of the two-dimensional centrally symmetric convex domains. It solved a problem opening for more than thirty years.

Metric Geometry · Mathematics 2007-06-14 Chuanming Zong

We give two new upper bounds on the covering minima of convex bodies, depending on covering minima of certain projections and intersections with linear subspaces. We show one bound to be sharp for direct sums of two convex bodies,…

Combinatorics · Mathematics 2026-05-12 Katarina Krivokuća

In this paper, we consider the problem of covering a plane region with unit discs. We present an improved upper bound and the first nontrivial lower bound on the number of discs needed for such a covering, depending on the area and…

Computational Geometry · Computer Science 2021-08-03 Shai Gul , Reuven Cohen , Simi Haber

A small polygon is a polygon of unit diameter. The maximal perimeter and the maximal width of a convex small polygon with $n=2^s$ vertices are not known when $s \ge 4$. In this paper, we construct a family of convex small $n$-gons, $n=2^s$…

Optimization and Control · Mathematics 2022-12-27 Christian Bingane
‹ Prev 1 2 3 10 Next ›