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Related papers: Making Multicurves Cross Minimally on Surfaces

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The set \[ \Gamma {\stackrel{\rm def}{=}} \{(z+w,zw):|z|\leq 1,|w|\leq 1\} \subset {\mathbb{C}}^2 \] has intriguing complex-geometric properties; it has a 3-parameter group of automorphisms, its distinguished boundary is a ruled surface…

Complex Variables · Mathematics 2017-12-25 Jim Agler , Zinaida A. Lykova , Nicholas J. Young

The problem on the minimal number (with respect to deformation) of intersection points of two closed curves on a surface is solved. Following the Nielsen approach, we define classes of intersection points and essential classes of…

Algebraic Topology · Mathematics 2016-01-12 Semeon A. Bogatyi , Elena A. Kudryavtseva , Heiner Zieschang

Let $\Gamma$ denote a distance-regular graph with classical parameters $(D, b, \alpha, \beta)$ and $D\geq 3$. Assume the intersection numbers $a_1=0$ and $a_2\not=0$. We show $\Gamma$ is 3-bounded in the sense of the article [D-bounded…

Combinatorics · Mathematics 2007-09-06 Yeh-jong Pan , Chih-wen Weng

Every graph $\Gamma$ can be embedded in the plane with a minimal number of edge intersections, called its classical crossing number $\text{cross}\left(\Gamma\right)$. In this paper, we prove that if $\Gamma$ is a metric graph it can be…

Algebraic Geometry · Mathematics 2016-04-22 Adan Medrano Martin del Campo , Sylvain Carpentier

Let $(M,g)$ be a compact Riemannian surface with nonpositive sectional curvature and let $\gamma$ be a closed geodesic in $M$. And let $e_\lambda$ be an $L^2$-normalized eigenfunction of the Laplace-Beltrami operator $\Delta_g$ with…

Analysis of PDEs · Mathematics 2018-05-30 Emmett L. Wyman

We provide theoretical insights around the cutwidth of a graph and the One-Sided Crossing Minimization (OSCM) problem. OSCM was posed in the Parameterized Algorithms and Computational Experiments Challenge 2024, where the cutwidth of the…

Data Structures and Algorithms · Computer Science 2025-01-20 Johannes Rauch , Dieter Rautenbach

We consider problems related to finding short cycles, small cliques, small independent sets, and small subgraphs in geometric intersection graphs. We obtain a plethora of new results. For example: * For the intersection graph of $n$ line…

Computational Geometry · Computer Science 2022-11-11 Timothy M. Chan

In this paper, we consider the decomposition of multigraphs under minimum degree constraints and give a unified generalization of several results by various researchers. Let $G$ be a multigraph in which no quadrilaterals share edges with…

Combinatorics · Mathematics 2020-09-07 Qinghou Zeng , Chunlei Zu

We propose a volumetric formulation for computing the Optimal Transport problem defined on surfaces in $\mathbb{R}^3$, found in disciplines like optics, computer graphics, and computational methodologies. Instead of directly tackling the…

Numerical Analysis · Mathematics 2024-05-16 Richard Tsai , Axel G. R. Turnquist

Triangulated meshes have become ubiquitous discrete-surface representations. In this paper we address the problem of how to maintain the manifold properties of a surface while it undergoes strong deformations that may cause topological…

Computer Vision and Pattern Recognition · Computer Science 2020-12-11 Andrei Zaharescu , Edmond Boyer , Radu Horaud

We show that there are minimal graphs in R^{n+1} whose intersection with the portion of the horizontal hyperplane contained in the unit ball has any prescribed geometry, up to a small deformation. The proof hinges on the construction of…

Differential Geometry · Mathematics 2018-02-26 Alberto Enciso , M. Angeles Garcia-Ferrero , Daniel Peralta-Salas

This paper explores the relationship between closed curves on surfaces and their intersections. Like Dehn-Thurston coordinates for simple curves, we explore how to determine closed curves using the number of times they intersect other…

Geometric Topology · Mathematics 2023-08-29 Hugo Parlier , Binbin Xu

Suppose that $M$ is a $2$-dimensional oriented Riemannian manifold, and let $\gamma$ be a simple closed curve on $M$. Let $m \gamma$ denote the curve formed by tracing $\gamma$ $m$ times. We prove that if $m \gamma$ is contractible through…

Differential Geometry · Mathematics 2015-10-14 Gregory R. Chambers , Yevgeny Liokumovich

This chapter provides a comprehensive survey of foundational results and recent advances concerning minimal generating sets for the mapping class group of a nonorientable surface, $\mathrm{Mod}(N_{g})$, and its index-two twist subgroup,…

Geometric Topology · Mathematics 2025-11-24 Tulin Altunoz , Mehmetcik Pamuk , Oguz Yildiz

We analyze the $\Gamma$-convergence of sequences of free-discontinuity functionals arising in the modeling of linear elastic solids with surface discontinuities, including phenomena as fracture, damage, or material voids. We prove…

Analysis of PDEs · Mathematics 2020-10-15 Manuel Friedrich , Matteo Perugini , Francesco Solombrino

We study a large family of graph covering problems, whose definitions rely on distances, for graphs of bounded cyclomatic number (that is, the minimum number of edges that need to be removed from the graph to destroy all cycles). These…

Discrete Mathematics · Computer Science 2025-09-03 Dibyayan Chakraborty , Florent Foucaud , Anni Hakanen

Given a graph $G$, we define ${\bf bcg}(G)$ as the minimum $k$ for which $G$ can be contracted to the uniformly triangulated grid $\Gamma_{k}$. A graph class ${\cal G}$ has the SQG${\bf C}$ property if every graph $G\in{\cal G}$ has…

Combinatorics · Mathematics 2022-07-21 Julien Baste , Dimitrios M. Thilikos

Let $\Gamma$ be a smooth, closed, oriented, $(n-1)$-dimensional submanifold of $\mathbb{R}^{n+1}$. We show that there exist arbitrarily small perturbations $\Gamma'$ of $\Gamma$ with the property that minimizing integral $n$-currents with…

Differential Geometry · Mathematics 2024-05-27 Otis Chodosh , Christos Mantoulidis , Felix Schulze

The need to compute the intersections between a line and a high-order curve or surface arises in a large number of finite element applications. Such intersection problems are easy to formulate but hard to solve robustly. We introduce a…

Numerical Analysis · Mathematics 2020-11-09 Xiao Xiao , Laurent Buse , Fehmi Cirak

By a curve in R^d we mean a continuous map gamma:I -> R^d, where I is a closed interval. We call a curve gamma in R^d at most k crossing if it intersects every hyperplane at most k times (counted with multiplicity). The at most d crossing…

Metric Geometry · Mathematics 2013-11-25 Imre Barany , Jiri Matousek , Attila Por