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In this paper, we prove the first incidence bound for points and conics over prime fields. As applications, we prove new results on expansion of bivariate polynomial images and on certain variations of distinct distances problems. These…

Combinatorics · Mathematics 2023-01-13 Ali Mohammadi , Thang Pham , Audie Warren

In this paper we present three different results dealing with the number of $(\leq k)$-facets of a set of points: 1. We give structural properties of sets in the plane that achieve the optimal lower bound $3\binom{k+2}{2}$ of $(\leq…

Combinatorics · Mathematics 2020-07-21 Oswin Aichholzer , Jesús García , David Orden , Pedro Ramos

We establish improved finite field Szemeredi-Trotter and Beck type theorems. First we show that if P and L are a set of points and lines respectively in the plane F_p^2, with |P|,|L| \leq N and N<p, then there are at most C_1…

Combinatorics · Mathematics 2012-06-21 Timothy G. F. Jones

We collect some results in combinatorial geometry that follow from an inequality of Langer in algebraic geometry. Langer's inequality gives a lower bound on the number of incidences between a point set and its spanned lines, and was…

Combinatorics · Mathematics 2018-02-23 Frank de Zeeuw

We use methods from spectral graph theory to obtain bounds on the number of incidences between $k$-planes and $h$-planes in $\mathbb{F}_q^d$ which generalize a recent result given by Bennett, Iosevich, and Pakianathan (2014). More…

Combinatorics · Mathematics 2015-10-14 Nguyen Duy Phuong , Thang Pham , Le Anh Vinh

We prove three theorems giving extremal bounds on the incidence structures determined by subsets of the points and blocks of a balanced incomplete block design (BIBD). These results generalize and strengthen known bounds on the number of…

Combinatorics · Mathematics 2016-12-28 Ben Lund , Shubhangi Saraf

We present a direct and fairly simple proof of the following incidence bound: Let $P$ be a set of $m$ points and $L$ a set of $n$ lines in ${\mathbb R}^d$, for $d\ge 3$, which lie in a common algebraic two-dimensional surface of degree $D$…

Algebraic Geometry · Mathematics 2015-06-03 Micha Sharir , Noam Solomon

We prove almost tight bounds on incidences between points and $k$-dimensional varieties of bounded degree in $\R^d$. Our main tools are the Polynomial Ham Sandwich Theorem and induction on both the dimension and the number of points.

Combinatorics · Mathematics 2017-03-17 Jozsef Solymosi , Terence Tao

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

We first describe a reduction from the problem of lower-bounding the number of distinct distances determined by a set $S$ of $s$ points in the plane to an incidence problem between points and a certain class of helices (or parabolas) in…

Computational Geometry · Computer Science 2010-05-07 György Elekes , Micha Sharir

The point-plane incidence theorem states that the number of incidences between $n$ points and $m\geq n$ planes in the projective three-space over a field $F$, is $$O\left(m\sqrt{n}+ m k\right),$$ where $k$ is the maximum number of collinear…

Combinatorics · Mathematics 2018-06-12 Misha Rudnev

In this note we give a shortened proof of a theorem of Rudnev, which bounds the number of incidences between points and planes over an arbitrary field. Rudnev's proof uses a map that goes via the four-dimensional Klein quadric to a…

Combinatorics · Mathematics 2016-12-09 Frank de Zeeuw

Incidence problems between geometric objects is a key area of focus in the field of discrete geometry. Among them, the study of incidence problems over finite fields have received a considerable amount of attention in recent years. In this…

Combinatorics · Mathematics 2025-05-01 Xiangliang Kong , Itzhak Tamo

We prove an incidence theorem for points and curves in the complex plane. Given a set of $m$ points in ${\mathbb R}^2$ and a set of $n$ curves with $k$ degrees of freedom, Pach and Sharir proved that the number of point-curve incidences is…

Combinatorics · Mathematics 2018-07-18 Adam Sheffer , Endre Szabó , Joshua Zahl

In this paper we establish an improved bound for the number of incidences between a set $P$ of $m$ points and a set $H$ of $n$ planes in $\mathbb R^3$, provided that the points lie on a two-dimensional nonlinear irreducible algebraic…

Combinatorics · Mathematics 2017-05-31 Micha Sharir , Noam Solomon

We prove new bounds on the number of incidences between points and higher degree algebraic curves. The key ingredient is an improved initial bound, which is valid for all fields. Then we apply the polynomial method to obtain global bounds…

Combinatorics · Mathematics 2015-03-31 Hong Wang , Ben Yang , Ruixiang Zhang

Let $p_1,\ldots,p_n$ be a set of points in the unit square and let $T_1,\ldots,T_n$ be a set of $\delta$-tubes such that $T_j$ passes through $p_j$. We prove a lower bound for the number of incidences between the points and tubes under a…

Combinatorics · Mathematics 2025-03-19 Alex Cohen , Cosmin Pohoata , Dmitrii Zakharov

Let $P$ be a set of $m$ points and $L$ a set of $n$ lines in $\mathbb R^4$, such that the points of $P$ lie on an algebraic three-dimensional surface of degree $D$ that does not contain hyperplane or quadric components, and no 2-flat…

Combinatorics · Mathematics 2016-09-29 Micha Sharir , Noam Solomon

Given a set of points $P$ and a set of regions $\mathcal{O}$, an incidence is a pair $(p,o ) \in P \times \mathcal{O}$ such that $p \in o$. We obtain a number of new results on a classical question in combinatorial geometry: What is the…

Computational Geometry · Computer Science 2023-02-27 Timothy M. Chan , Sariel Har-Peled

We generalize the Szemer\'edi-Trotter incidence theorem, to bound the number of complete \emph{flags} in higher dimensions. Specifically, for each $i=0,1,\ldots,d-1$, we are given a finite set $S_i$ of $i$-flats in $\R^d$ or in $\C^d$, and…

Combinatorics · Mathematics 2015-12-31 Saarik Kalia , Micha Sharir , Noam Solomon , Ben Yang
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