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Related papers: On the joints problem with multiplicities

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We generalize the Guth--Katz joints theorem from lines to varieties. A special case says that $N$ planes (2-flats) in 6 dimensions (over any field) have $O(N^{3/2})$ joints, where a joint is a point contained in a triple of these planes not…

Combinatorics · Mathematics 2022-06-03 Jonathan Tidor , Hung-Hsun Hans Yu , Yufei Zhao

We present a new proof of the Joints Theorem without taking derivatives. Then we generalize the proof to prove the Multijoints Conjecture and Carbery's generalization. All results are in any dimension over an arbitrary field.

Combinatorics · Mathematics 2017-05-10 Ruixiang Zhang

We give a proof of the "folklore" theorem that the Kaplan--Sharir--Shustin/Quilodr\'an result on counting joints associated to a family of lines holds in vector spaces over arbitrary fields, not just the reals. We also discuss a…

Combinatorics · Mathematics 2014-05-30 Anthony Carbery , Marina Iliopoulou

A uniform bound of intersection multiplicities of curves and divisors on abelian varieties is proved by algebraic geometric methods. It extends and improves a result obtained by A. Buium with a different method based on Kolchin's…

Algebraic Geometry · Mathematics 2007-05-23 Junjiro Noguchi , Joerg Winkelmann

A joint of a set of lines $\mathcal{L}$ in $\mathbb{F}^d$ is a point that is contained in $d$ lines with linearly independent directions. The joints problem asks for the maximum number of joints that are formed by $L$ lines. Guth and Katz…

Combinatorics · Mathematics 2023-12-25 Ting-Wei Chao , Hung-Hsun Hans Yu

We generalize the joints problem to sets of varieties and prove almost sharp bound on the number of joints. As a special case, given a set of $N$ $2$-planes in $\mathbb{R}^6$, the number of points at which three $2$-planes intersect and…

Combinatorics · Mathematics 2016-06-29 Ben Yang

We show that given a collection of A lines in \R^n, n\geq 2, the maximum number of their joints (points incident to at least n lines whose directions form a linearly independent set) is O(A^{n/(n-1)}). An analogous result for smooth…

Combinatorics · Mathematics 2009-06-15 René Quilodrán

We establish new bounds on the number of tangencies and orthogonal intersections determined by an arrangement of curves. First, given a set of $n$ algebraic plane curves, we show that there are $O(n^{3/2})$ points where two or more curves…

Combinatorics · Mathematics 2018-07-10 Jordan S. Ellenberg , Jozsef Solymosi , Joshua Zahl

A new generalization of the classical separate algebraicity theorem is suggested and proved.

alg-geom · Mathematics 2008-02-03 R. A. Sharipov , E. N. Tzyganov

Let $\mathfrak{L}$ be a collection of $L$ lines in $\R^3$ and $J$ the set of joints formed by $\mathfrak{L}$, i.e. the set of points each of which lies in at least 3 non-coplanar lines of $\mathfrak{L}$. It is known that $|J| \lesssim…

Combinatorics · Mathematics 2014-02-26 Marina Iliopoulou

In this note, we present recent progress on rigidity problems in one-dimensional complex dynamics, including the proof of Dynamical Andr\'e-Oort conjecture for curves and generic injectivity of multiplier spectrum. The proofs combine ideas…

Algebraic Geometry · Mathematics 2025-11-18 Junyi Xie

We give a combinatorial upper bound for the gonality of a curve that is defined by a bivariate Laurent polynomial with given Newton polygon. We conjecture that this bound is generically attained, and provide proofs in a considerable number…

Algebraic Geometry · Mathematics 2012-01-17 Wouter Castryck , Filip Cools

In this paper we derive an upper bound for the degree of the strict invariant algebraic curve of a polynomial system in the complex project plane under generic condition. The results are obtained through the algebraic multiplicities of the…

Classical Analysis and ODEs · Mathematics 2023-09-29 Jinzhi Lei , Lijun Yang

In the long paper "Family Blowup formula, Admissible Graphs and the Enumeration of Singular Curves (I)" (appearing in JDG), the author solved the enumeration problem of nodal (or general singular) curve counting on algebraic surfaces by…

Algebraic Geometry · Mathematics 2007-05-23 Ai-Ko Liu

A geometric argument is given to prove that the Seifert genus of a positive knot equals its slice genus. A combinatorial invariant, giving a lower bound for the slice genus, is formulated for arbitrary knots. Properties and applications of…

Geometric Topology · Mathematics 2012-05-22 Vyacheslav Krushkal

The geometric torsion conjecture asserts that the torsion part of the Mordell--Weil group of a family of abelian varieties over a complex quasiprojective curve is uniformly bounded in terms of the genus of the curve. We prove the conjecture…

Algebraic Geometry · Mathematics 2015-04-09 Benjamin Bakker , Jacob Tsimerman

We study the "generic" degenerations of curves with two singular points when the points merge. First, the notion of generic degeneration is defined precisely. Then a method to classify the possible results of generic degenerations is…

Algebraic Geometry · Mathematics 2009-04-21 Dmitry Kerner

Let $\mathfrak{L}_1$, $\mathfrak{L}_2$, $\mathfrak{L}_3$ be finite collections of $L_1$, $L_2$, $L_3$, respectively, lines in $\mathbb{R}^3$, and $J(\mathfrak{L}_1, \mathfrak{L}_2,\mathfrak{L}_3)$ the set of multijoints formed by them, i.e.…

Combinatorics · Mathematics 2014-01-27 Marina Iliopoulou

We give a bound on the number of weighted real forms of a complex variety with finite automorphism group, where the weight is the inverse of the number of automorphisms of the real form. We give another bound involving the Sylow 2-subgroup…

Algebraic Geometry · Mathematics 2026-05-27 Gerard van der Geer , Xun Yu

We prove a boundedness-theorem for families of abelian varieties with real multiplication. More generally, we study curves in Hilbert modular varieties from the point of view of the Green Griffiths-Lang conjecture claiming that entire…

Algebraic Geometry · Mathematics 2018-10-01 Erwan Rousseau , Frédéric Touzet
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