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We use computational experiments to find the rectangles of minimum area into which a given number n of non-overlapping congruent circles can be packed. No assumption is made on the shape of the rectangles. Most of the packings found have…

Metric Geometry · Mathematics 2007-05-23 Boris D. Lubachevsky , Ronald Graham

In this article, we prove that there exists a unique perimeter minimizer among all piecewise smooth simple closed curves in $M_{\kappa}^2$ enclosing area $A > 0$ $(A \leq 2{\pi}$ if ${\kappa} = 1)$, and it is a circle in $M_{\kappa}^2$ of…

Differential Geometry · Mathematics 2024-08-27 A R Aithal , Anisa M H Chorwadwala

In this paper it has been verified, by a computer-based proof, that the smallest size of a complete arc is 14 in PG(2,31) and in PG(2,32). Some examples of such arcs are also described.

Combinatorics · Mathematics 2010-05-20 Stefano Marcugini , Alfredo Milani , Fernanda Pambianco

We show that we can obtain a reducible spherical curve from any non-trivial spherical curve by four or less inverse-half-twisted splices, i.e., the reductivity, which represents how reduced a spherical curve is, is four or less. We also…

Geometric Topology · Mathematics 2014-01-17 Ayaka Shimizu

What is the minimum angle $\alpha >0$ such that given any set of $\alpha$-directional antennas (that is, antennas each of which can communicate along a wedge of angle $\alpha$), one can always assign a direction to each antenna such that…

Computational Geometry · Computer Science 2011-07-26 Eyal Ackerman , Tsachik Gelander , Rom Pinchasi

We provide an efficient algorithm to compute the minimum area of a homotopy between two closed plane curves, given that they divide the plane into finite number of regions. For any positive real number $\varepsilon>0$, we construct a closed…

Geometric Topology · Mathematics 2015-01-05 Zipei Nie

We prove that the least area of the non-contractible immersed spheres is no more than $4\pi$ in any oriented compact manifold with dimension $n+2\leq 7$ which satisfies $R\geq 2$ and admits a map to $\mathbf S^2\times T^n$ with nonzero…

Differential Geometry · Mathematics 2019-03-29 Jintian Zhu

We introduce and motivate a conjecture about the existence of complete, 1-dimensional families of covers of an elliptic curve. If the conjecture holds, then it would imply a uniform lower bound of 5 for slope of the moduli space of curves.…

Algebraic Geometry · Mathematics 2026-01-14 Gabriel Bujokas , Anand Patel

It is known that $\sum\limits_{i=1}^{\infty} \frac{1}{i (i+1)} = 1$. In 1968, Meir and Moser asked for finding the smallest $\epsilon$ such that all the rectangles of sizes $1/i \times 1/(i + 1)$ for $i = 1, 2, \ldots$, can be packed into a…

Combinatorics · Mathematics 2022-11-21 Mingliang Zhu , Antal Joós

In this paper, we study the curvature properties of random complex plane curves. We bound from below the probability that a uniform proportion of the area of a random complex degree $d$ plane curve has a curvature smaller than $-d/8$. Our…

Algebraic Geometry · Mathematics 2024-02-20 Michele Ancona , Damien Gayet

In this paper, the following two theorems are proved: $(1)$ every spherical convex body $W$ of constant width $\Delta (W) \geq \frac{\pi}{2}$ may be covered by a disk of radius $\Delta(W) + \arcsin \left( \frac{2\sqrt{3}}{3} \cdot \cos…

Metric Geometry · Mathematics 2018-06-13 Michał Musielak

This paper focuses on curves and surfaces of constant width, with some additional results about general ovals. We emphasize the use of Fourier series to derive properties, some of which are known. Amongst other results, we show that the…

Differential Geometry · Mathematics 2015-04-28 Howard L. Resnikoff

This note provides some new perspectives and calculations regarding an interesting known family of minimal surfaces in $\mathbb{H}^2 \times \mathbb{R}$. The surfaces in this family are the catenoids, parabolic catenoids and tall rectangles.…

Differential Geometry · Mathematics 2019-01-15 Leonor Ferrer , Francisco Martín , Rafe Mazzeo , Magdalena Rodríguez

With the popularity of drone technologies, aerial photography has become prevalent in many daily scenarios such as environment monitoring, structure inspection, law enforcement etc. A central challenge in this domain is the efficient…

Robotics · Computer Science 2025-12-30 Si Wei Feng

A covering problem posed by Henri Lebesgue in 1914 seeks to find the convex shape of smallest area that contains a subset congruent to any point set of unit diameter in the Euclidean plane. Methods used previously to construct such a…

Metric Geometry · Mathematics 2018-10-25 Philip Gibbs

A pseudocircle is a simple closed curve on some surface; an arrangement of pseudocircles is a collection of pseudocircles that pairwise intersect in exactly two points, at which they cross. Ortner proved that an arrangement of pseudocircles…

Moser asked whether the collection of rectangles of dimensions 1 x 1/2, 1/2 x 1/3, 1/3 x 1/4, ..., whose total area equals 1, can be packed into the unit square without overlap, and whether the collection of squares of side lengths 1/2,…

Metric Geometry · Mathematics 2007-05-23 Greg Martin

Let $S$ be a set of $n$ points in the unit square $[0,1]^2$, one of which is the origin. We construct $n$ pairwise interior-disjoint axis-aligned empty rectangles such that the lower left corner of each rectangle is a point in $S$, and the…

Combinatorics · Mathematics 2012-07-31 Adrian Dumitrescu , Csaba D. Tóth

The reductivity of a spherical curve is the minimal number of a local transformation called an inverse-half-twisted splice required to obtain a reducible spherical curve from the spherical curve. It is unknown if there exists a spherical…

Geometric Topology · Mathematics 2018-10-12 Kenji Kashiwabara , Ayaka Shimizu

This paper contains a comparative study of two families of simple curves drawn in the plane. On the one hand, we have the fractal curves on the unit interval, with self-similar structure, which have associated a Hausdorff dimension. On the…

Classical Analysis and ODEs · Mathematics 2015-04-07 R. Hansen , M. Piacquadio