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Related papers: Incidence theorems for pseudoflats

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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 propose a skein model for the quantum cluster algebras of surface type with coefficients. We introduce a skein algebra $\mathscr{S}_{\Sigma,\mathbb{W}}^{A}$ of a walled surface $(\Sigma,\mathbb{W})$, and prove that it has a quantum…

Geometric Topology · Mathematics 2024-08-23 Tsukasa Ishibashi , Shunsuke Kano , Wataru Yuasa

It is known that in the case of hyperelliptic curves the Shafarevich conjecture can be made effective, i.e., for any number field k and any finite set of places S of k, one can effectively compute the set of isomorphism classes of…

Number Theory · Mathematics 2012-03-06 Aaron Levin

We consider coverings of real algebraic curves to real rational algebraic curves. We show the existence of such coverings having prescribed topological degree on the real locus. From those existence results we prove some results on…

Algebraic Geometry · Mathematics 2011-07-26 Marc Coppens , Johannes Huisman

We apply the loop group method developed by Zakharov-Shabat, Terng-Uhlenbeck and Toda to the study of symmetries of pseudospherical surfaces in R^3. In this paper (part I) we consider the general theory, while in a second paper (part II) we…

Differential Geometry · Mathematics 2009-07-06 Josef F. Dorfmeister , Thomas A. Ivey , Ivan Sterling

Smooth complex surfaces polarized with an ample and globally generated line bundle of degree three and four, such that the adjoint bundle is not globally generated, are considered. Scrolls of a vector bundle over a smooth curve are shown to…

Algebraic Geometry · Mathematics 2007-05-23 Gian Mario Besana , Sandra Di Rocco

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 generalize Iskovskih's theorem about surfaces without irregularity and bigenus from the smooth case to regular surfaces over arbitrary fields, with special focus on the case of imperfect fields. This includes surfaces that are…

Algebraic Geometry · Mathematics 2025-03-14 Andrea Fanelli , Stefan Schröer

Guided by the ideas of chirality in the abstract polytope theory, the present paper aims to extend the concept to a more general setting of incidence geometries. The purpose of this paper is to explore the more general framework of thin…

Group Theory · Mathematics 2016-04-13 Maria Elisa Fernandes , Dimitri Leemans , Asia Ivić Weiss

This is the second of two articles in which we prove a sharp $L^p-L^2$ Fourier restriction theorem for a large class of smooth, finite type hypersurfaces in R^3, which includes in particular all real-analytic hypersurfaces.

Classical Analysis and ODEs · Mathematics 2014-10-14 Isroil A. Ikromov , Detlef Müller

We consider a class of equations with exponential non-linearities on a compact surface which arises as the mean field equation of the equilibrium turbulence with arbitrarily signed vortices. We prove an existence result via degree theory.…

Analysis of PDEs · Mathematics 2017-03-07 Aleks Jevnikar

We consider evolution equations for curves in the 3-dimensional sphere $S^3$ that are invariant under the group $SU(2,1)$ of pseudoconformal transformations, which preserves the standard contact structure on the sphere. In particular, we…

Differential Geometry · Mathematics 2019-08-08 Annalisa Calini , Thomas Ivey

We prove an optimal restriction theorem for an arbitrary homogeneous polynomial hypersurface (of degree at least 2) in R^3, with affine curvature introduced as mitigating factor.

Classical Analysis and ODEs · Mathematics 2011-08-23 A. Carbery , C. Kenig , S. Ziesler

The Severi variety $V_{d,n}$ of plane curves of a given degree $d$ and exactly $n$ nodes admits a map to the Hilbert scheme $\mathbb{P}^{2[n]}$ of zero-dimensional subschemes of $\mathbb{P}^2$ of degree $n$. This map assigns to every curve…

Algebraic Geometry · Mathematics 2021-11-04 Cesar Lozano Huerta , Tim Ryan

We survey recent (and not so recent) results concerning arrangements of lines, points and other geometric objects and the applications these results have in theoretical computer science and combinatorics. The three main types of problems we…

Combinatorics · Mathematics 2015-03-20 Zeev Dvir

We complete the remaining cases of the conjecture predicting existence of infinitely many rational curves on K3 surfaces in characteristic zero, prove almost all cases in positive characteristic and improve the proofs of the previously…

Algebraic Geometry · Mathematics 2023-05-24 Xi Chen , Frank Gounelas , Christian Liedtke

We prove that the integral Hodge conjecture holds for 1-cycles on irreducible holomorphic symplectic varieties of K3 type and of Generalized Kummer type. As an application, we give a new proof of the integral Hodge conjecture for cubic…

Algebraic Geometry · Mathematics 2019-08-09 Giovanni Mongardi , John Christian Ottem

Pach showed that every $d+1$ sets of points $Q_1,\dotsc,Q_{d+1} \subset \mathbb{R}^d$ contain linearly-sized subsets $P_i\subset Q_i$ such that all the transversal simplices that they span intersect. We show, by means of an example, that a…

Combinatorics · Mathematics 2019-11-20 Boris Bukh , Alfredo Hubard

We obtain a precise relation between the Chern-Schwartz-MacPherson class of a subvariety of projective space and the Euler characteristics of its general linear sections. In the case of a hypersurface, this leads to simple proofs of…

Algebraic Geometry · Mathematics 2013-07-04 Paolo Aluffi

We prove a general embedding theorem for Cohen--Macaulay curves (possibly nonreduced), and deduce a cheap proof of the standard results on pluricanonical embeddings of surfaces, assuming vanishing H^1(2K_X)=0.

alg-geom · Mathematics 2008-02-03 F. Catanese , M. Franciosi , K. Hulek , M. Reid