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Pseudoline arrangements are fundamental objects in discrete and computational geometry, and different works have tackled the problem of improving the known bounds on the number of simple arrangements of $n$ pseudolines over the past…

Computational Geometry · Computer Science 2025-03-10 Justin Dallant

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 1967, Moon and Moser proved a tight bound on the critical density of squares in squares: any set of squares with a total area of at most 1/2 can be packed into a unit square, which is tight. The proof requires full knowledge of the set,…

Discrete Mathematics · Computer Science 2017-01-03 Sándor P. Fekete , Hella-Franziska Hoffmann

We consider methods for finding a simple polygon of minimum (Min-Area) or maximum (Max-Area) possible area for a given set of points in the plane. Both problems are known to be NP-hard; at the center of the recent CG Challenge, practical…

Computational Geometry · Computer Science 2021-11-11 Sándor P. Fekete , Andreas Haas , Phillip Keldenich , Michael Perk , Arne Schmidt

Hadwiger's conjecture in convex geometry, formulated in 1957, states that every convex body in $\mathbb{R}^n$ can be covered by $2^n$ translations of its interior. Despite significant efforts, the best known bound related to this problem…

Metric Geometry · Mathematics 2024-10-16 Daniel Galicer , Joaquín Singer

Given a smooth simply connected planar domain, the area is bounded away from zero in terms of the maximal curvature alone. We show that in higher dimensions this is not true, and for a given maximal mean curvature we provide smooth…

Optimization and Control · Mathematics 2016-04-21 Vincenzo Ferone , Carlo Nitsch , Cristina Trombetti

For sufficiently large $n$, we show that in every configuration of $n$ points chosen inside the unit square there exists a triangle of area less than $n^{-8/7-1/2000}$. This improves upon a result of Koml\'os, Pintz and Szemer\'edi from…

Combinatorics · Mathematics 2023-05-30 Alex Cohen , Cosmin Pohoata , Dmitrii Zakharov

We provide a new upper bound for traveling salesman problem (TSP) in cubic graphs, i.e. graphs with maximum vertex degree three, and prove that the problem for an $n$-vertex graph can be solved in $O(1.2553^n)$ time and in linear space. We…

Data Structures and Algorithms · Computer Science 2012-12-03 Maciej Liskiewicz , Martin R. Schuster

It is proved that the total length of any set of countably many rectifiable curves, whose union meets all straight lines that intersect the unit square U, is at least 2.00002. This is the first improvement on the lower bound of 2…

Computational Geometry · Computer Science 2014-04-11 Akitoshi Kawamura , Sonoko Moriyama , Yota Otachi , János Pach

In 1946 Erd\H os asked for the maximum number of unit distances, $u(n)$, among $n$ points in the plane. He showed that $u(n)> n^{1+c/\log\log n}$ and conjectured that this was the true magnitude. The best known upper bound is…

Combinatorics · Mathematics 2014-04-22 Ryan Schwartz , József Solymosi , Frank de Zeeuw

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

Let $p$ be a positive number. Consider probability measure $\gamma_p$ with density $\varphi_p(y)=c_{n,p}e^{-\frac{|y|^p}{p}}$. We show that the maximal surface area of a convex body in $\mathbb{R}^n$ with respect to $\gamma_p$ is…

Classical Analysis and ODEs · Mathematics 2016-06-08 Galyna Livshyts

Given a point set $S=\{s_1,\ldots , s_n\}$ in the unit square $U=[0,1]^2$, an anchored square packing is a set of $n$ interior-disjoint empty squares in $U$ such that $s_i$ is a corner of the $i$th square. The reach $R(S)$ of $S$ is the set…

Computational Geometry · Computer Science 2018-06-26 Hugo A. Akitaya , Matthew D. Jones , David Stalfa , Csaba D. Tóth

The "Mahler volume" is, intuitively speaking, a measure of how "round" a centrally symmetric convex body is. In one direction this intuition is given weight by a result of Santalo, who in the 1940s showed that the Mahler volume is…

Metric Geometry · Mathematics 2018-11-07 Matthew Tointon

Let $S$ be a set of $n$ points in the plane, $\wp(S)$ be the set of all simple polygons crossing $S$, $\gamma_P$ be the maximum angle of polygon $P \in \wp(S)$ and $\theta =min_{P\in\wp(S)} \gamma_P$. In this paper, we prove that…

Computational Geometry · Computer Science 2021-06-15 Saeed Asaeedi , Farzad Didehvar , Ali Mohades

Let A be a bounded subset of IR^d. We give an upper bound on the volume of the symmetric difference of A and f(A) where f is a translation, a rotation, or the composition of both, a rigid motion. The volume is measured by the d-dimensional…

Metric Geometry · Mathematics 2010-10-13 Daria Schymura

We show that among any $n$ points in the unit cube one can find a triangle of area at most $n^{-2/3-c}$ for some absolute constant $c >0$. This gives the first non-trivial upper bound for the three-dimensional version of Heilbronn's…

Combinatorics · Mathematics 2025-10-31 Dominique Maldague , Hong Wang , Dmitrii Zakharov

We construct skew corner-free subsets of $[n]^2$ of size $n^2\exp(-O(\sqrt{\log n}))$, thereby improving on recent bounds of the form $\Omega(n^{5/4})$ obtained by Pohoata and Zakharov. In the other direction, we prove that any such set has…

Combinatorics · Mathematics 2025-04-30 Adrian Beker

It is shown that the maximum size $A_2(8,6;4)$ of a binary subspace code of packet length $v=8$, minimum subspace distance $d=4$, and constant dimension $k=4$ is at most $272$. In Finite Geometry terms, the maximum number of solids in…

Combinatorics · Mathematics 2017-03-28 Daniel Heinlein , Sascha Kurz

Given two pants decompositions of a compact orientable surface $S$, we give an upper bound for their distance in the pants graph that depends logarithmically on their intersection number and polynomially on the Euler characteristic of $S$.…

Geometric Topology · Mathematics 2025-11-06 Marc Lackenby , Mehdi Yazdi