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Related papers: Crossing number of curves on surfaces

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This article is the first in a series of two in which we study the vanishing cycles of curves in toric surfaces. We give a list of possible obstructions to contract vanishing cycles within a given complete linear system. Using tropical…

Algebraic Geometry · Mathematics 2019-03-15 Rémi Crétois , Lionel Lang

We prove the following results: (1) For every generic closed smooth curve in $\mathbb{R}^3$ there is a point with at least $6$ emanating normals to the curve. (2) For every generic closed piecewise linear curve in $\mathbb{R}^3$ there is a…

Differential Geometry · Mathematics 2026-03-02 Gaiane Panina , Dirk Siersma

The {\it crossing number} of a graph $G$ is the minimum number of pairwise intersections of edges in a drawing of $G$. The {\it $n$-dimensional folded hypercube} $FQ_n$ is a graph obtained from $n$-dimensional hypercube by adding all…

Combinatorics · Mathematics 2015-03-17 Haoli Wang , Yuansheng Yang , Yan Zhou , Wenping Zheng , Guoqing Wang

We consider ruled surfaces with finite multiplicity. We study behaviors of the striction curves and the singularities of the ruled surfaces. We also give geometric meanings of invariants related to the ruled surfaces.

Differential Geometry · Mathematics 2025-05-21 Hiroyuki Hayashi

Let $G$ be a multigraph with $n$ vertices and $e>4n$ edges, drawn in the plane such that any two parallel edges form a simple closed curve with at least one vertex in its interior and at least one vertex in its exterior. Pach and T\'oth (A…

Combinatorics · Mathematics 2021-10-20 Michael Kaufmann , Janos Pach , Geza Toth , Torsten Ueckerdt

In this paper, we consider rational cuspidal plane curves having at least three cusps. We give an upper bound of the self-intersection number of the proper transforms of such curves via the minimal embedded resolution of the cusps. For a…

Algebraic Geometry · Mathematics 2014-08-04 Keita Tono

Research about crossings is typically about minimization. In this paper, we consider \emph{maximizing} the number of crossings over all possible ways to draw a given graph in the plane. Alpert et al. [Electron. J. Combin., 2009] conjectured…

Computational Geometry · Computer Science 2017-05-16 Markus Chimani , Stefan Felsner , Stephen Kobourov , Torsten Ueckerdt , Pavel Valtr , Alexander Wolff

We classify the singular loci of real surfaces in three-space that contain two circles through each point. We characterize how a circle in such a surface meets this loci as it moves in its pencil and as such provide insight into the…

Algebraic Geometry · Mathematics 2024-10-01 Niels Lubbes

We consider the problem of finding curves of minimum pointwise-maximum curvature, i.e., curves of minimax curvature, among planar curves of fixed length with prescribed endpoints and tangents at the endpoints. We reformulate the problem in…

Optimization and Control · Mathematics 2024-04-22 C. Yalçın Kaya , Lyle Noakes , Philip Schrader

We give an explicitly computable lower bound for the arithmetic self-intersection number of the dualizing sheaf on a large class of arithmetic surfaces. If some technical conditions are satisfied, then this lower bound is positive. In…

Number Theory · Mathematics 2013-07-22 Ulf Kühn , Jan Steffen Müller

We study the following question: given a set P of 3d-2 points and an immersed curve G in the real plane R^2, all in general position, how many real rational plane curves of degree d pass through these points and are tangent to this curve.…

Geometric Topology · Mathematics 2012-08-21 Sergei Lanzat , Michael Polyak

This article deals with the set of closed geodesics on complete finite type hyperbolic surfaces. For any non-negative integer $k$, we consider the set of closed geodesics that self-intersect at least $k$ times, and investigate those of…

Geometric Topology · Mathematics 2019-12-23 Thi Hanh Vo

For two oriented simple closed curves on a compact orientable surface with a connected boundary we introduce a simple computation of a value in the first homology group of the surface, which detects in some cases that the geometric…

Geometric Topology · Mathematics 2016-12-07 Ryosuke Yamamoto

Given an n-vertex graph G, a drawing of G in the plane is a mapping of its vertices into points of the plane, and its edges into continuous curves, connecting the images of their endpoints. A crossing in such a drawing is a point where two…

Data Structures and Algorithms · Computer Science 2010-10-20 Julia Chuzhoy , Yury Makarychev , Anastasios Sidiropoulos

For a smooth plane cubic $B$, we count curves $C$ of degree $d$ such that the normalizations of $C\backslash B$ are isomorphic to $\Bbb A^1$, for $d\leq7$ (for $d=7$ under some assumption). We also count plane rational quartic curves…

alg-geom · Mathematics 2008-02-03 Nobuyoshi Takahashi

The fine 1-curve graph of a surface is a graph whose vertices are simple closed curves on the surface and whose edges connect vertices that intersect in at most one point. We show that the automorphism group of the fine 1-curve graph is…

Geometric Topology · Mathematics 2023-09-29 Katherine Williams Booth , Daniel Minahan , Roberta Shapiro

In characteristic $p>0$ and for $q$ a power of $p$, we compute the number of nonplanar rational curves of arbitrary degrees on a smooth Hermitian surface of degree $q+1$ under the assumption that the curves have a parametrization given by…

Algebraic Geometry · Mathematics 2020-03-31 Norifumi Ojiro

The main goal of this paper is to investigate the minimal size of families of curves on surfaces with the following property: a family of simple closed curves $\Gamma$ on a surface realizes all types of pants decompositions if for any pants…

Geometric Topology · Mathematics 2023-02-16 Niloufar Fuladi , Arnaud de Mesmay , Hugo Parlier

We present an algorithm for computing curves and families of curves of prescribed degree and geometric genus on real rational surfaces.

Algebraic Geometry · Mathematics 2018-05-11 Niels Lubbes

In this paper, we consider the automorphisms of fine curve graphs restricted to continuously $k$-differentiable curves. We show that for closed surfaces with genus at least 2, they are induced by homeomorphisms of the surface.

Geometric Topology · Mathematics 2024-10-31 Katherine Williams Booth