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Related papers: Intersection of ACM-curves in P^3

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We give an exponential upper and a quadratic lower bound on the number of pairwise non-isotopic simple closed curves can be placed on a closed surface of genus g such that any two of the curves intersects at most once. Although the gap is…

Geometric Topology · Mathematics 2013-01-04 Justin Malestein , Igor Rivin , Louis Theran

We reach beyond the celebrated theorems of Erd\H{o}s-Ko-Rado and Hilton-Milner, and, a recent theorem of Han-Kohayakawa, and determine all maximal intersecting triples systems. It turns out that for each $n\ge7$ there are exactly 15…

Combinatorics · Mathematics 2016-08-23 Joanna Polcyn , Andrzej Rucinski

The degree-diameter problem seeks to find the maximum possible order of a graph with a given (maximum) degree and diameter. It is known that graphs attaining the maximum possible value (the Moore bound) are extremely rare, but much activity…

Combinatorics · Mathematics 2016-05-03 Dominique Buset , Mourad El Amiri , Grahame Erskine , Hebert Pérez-Rosés , Mirka Miller

A generalization of the Kontsevich Airy-model allows one to compute the intersection numbers of the moduli space of p-spin curves. These models are deduced from averages of characteristic polynomials over Gaussian ensembles of random…

High Energy Physics - Theory · Physics 2009-05-01 E. Brezin , S. Hikami

Given finitely many connected polygonal obstacles $O_1,\dots,O_k$ in the plane and a set $P$ of points in general position and not in any obstacle, the {\em visibility graph} of $P$ with obstacles $O_1,\dots,O_k$ is the (geometric) graph…

Combinatorics · Mathematics 2017-09-08 John Gimbel , Patrice Ossona de Mendez , Pavel Valtr

The definition of the intersection number of a map with a closed manifold can be extended to the case of a closed stratified set such that the difference between dimensions of its two biggest strata is greater than $1$. The set Sigma of…

Differential Geometry · Mathematics 2021-01-08 Iwona Krzyżanowska , Aleksandra Nowel

The minimum number of self-intersection points for members of a free homotopy class of curves on the punctured torus is bounded above in terms of the number L of letters required for a minimal description of the class in terms of the…

Geometric Topology · Mathematics 2009-01-21 Moira Chas , Anthony Phillips

We determine that the maximum crossing number of $C_3 \times C_3$ is 78, which closes the previously best known range of between 68 and 80. The proof uses several techniques which may be useful in determining the maximum crossing number of…

Combinatorics · Mathematics 2020-05-18 Michael Haythorpe , Alex Newcombe

We prove that, for the edge ideal of a cactus graph, the arithmetical rank is bounded above by the sum of the number of cycles and the maximum height of its associated primes. The bound is sharp, but in many cases it can be improved.…

Commutative Algebra · Mathematics 2017-03-28 Margherita Barile , Antonio Macchia

We describe a general algorithm for computing intersection pairings on arithmetic surfaces. We have implemented our algorithm for curves over $\mathbb Q$, and we show how to use it to compute regulators for a number of Jacobians of smooth…

Number Theory · Mathematics 2019-04-04 Raymond van Bommel , David Holmes , J. Steffen Müller

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

An adjacency-crossing graph is a graph that can be drawn such that every two edges that cross the same edge share a common endpoint. We show that the number of edges in an $n$-vertex adjacency-crossing graph is at most $5n-10$. If we…

Combinatorics · Mathematics 2023-09-14 Eyal Ackerman , Balázs Keszegh

The number of embeddings of minimally rigid graphs in $\mathbb{R}^D$ is (by definition) finite, modulo rigid transformations, for every generic choice of edge lengths. Even though various approaches have been proposed to compute it, the gap…

Algebraic Geometry · Mathematics 2020-01-24 Evangelos Bartzos , Ioannis Emiris , Jan Legerský , Elias Tsigaridas

We prove an incidence theorem for points and planes in the projective space $\mathbb P^3$ over any field $\mathbb F$, whose characteristic $p\neq 2.$ An incidence is viewed as an intersection along a line of a pair of two-planes from two…

Combinatorics · Mathematics 2015-12-07 Misha Rudnev

The problem of computing a linear combination of sources over a multiple access channel is studied. Inner and outer bounds on the optimal tradeoff between the communication rates are established when encoding is restricted to random…

Information Theory · Computer Science 2018-10-30 Pinar Sen , Sung Hoon Lim , Young-Han Kim

We prove that for every integer $t\geq 1$, the class of intersection graphs of curves in the plane each of which crosses a fixed curve in at least one and at most $t$ points is $\chi$-bounded. This is essentially the strongest…

Combinatorics · Mathematics 2017-10-05 Alexandre Rok , Bartosz Walczak

A classical inequality which is due to Lickorish and Hempel says that the distance between two curves in the curve complex can be measured by their intersection number. In this paper, we show a converse version; the intersection number of…

Geometric Topology · Mathematics 2016-04-27 Yohsuke Watanabe

Using an Euclidean approach, we prove a new upper bound for the number of closed points of degree 2 on a smooth absolutely irreducible projective algebraic curve defined over the finite field $\mathbb F\_q$.This bound enables us to provide…

Algebraic Geometry · Mathematics 2015-10-08 Yves Aubry , Annamaria Iezzi

We study the following question: fix a sufficient general curve D of degree d in P^2, what is the least number of intersections between D and an irreducible curve of degree m? G. Xu proved this number i(d, m) is at least d - 2 for all m.…

Algebraic Geometry · Mathematics 2007-05-23 Xi Chen

We study the number of intersections of the nodal lines of an eigenfunction of the Laplacian on the standard torus with a fixed reference curve, that is, the number of zeros of the eigenfunction restricted to the curve. An upper bound is…

Analysis of PDEs · Mathematics 2014-02-05 Jean Bourgain , Zeev Rudnick