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Related papers: Incidence Bounds for Block Designs

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We give a precise definition of incidence theorems in plane projective geometry and introduce the notion of ``absolute incidence theorems,'' which hold over any ring. Fomin and Pylyavskyy describe how to obtain incidence theorems from…

Combinatorics · Mathematics 2025-12-17 Lukas Kühne , Matt Larson

Design matrices are sparse matrices in which the supports of different columns intersect in a few positions. Such matrices come up naturally when studying problems involving point sets with many collinear triples. In this work we consider…

Combinatorics · Mathematics 2018-03-13 Zeev Dvir , Ankit Garg , Rafael Oliveira , József Solymosi

We prove that for any $K$ and $d$, there exist, for all sufficiently large admissible $v$, a pairwise balanced design PBD$(v,K)$ of dimension $d$ for which all $d$-point-generated flats are bounded by a constant independent of $v$. We also…

Combinatorics · Mathematics 2014-10-29 Nicholas M. A. Benson , Peter J. Dukes

This study presents an extension of multiscale topology optimization by integrating both yield stress and local/global buckling considerations into the design process. Building upon established multiscale methodologies, we develop a new…

Computational Engineering, Finance, and Science · Computer Science 2025-05-08 Christoffer Fyllgraf Christensen , Fengwen Wang , Ole Sigmund

In this paper we show that the number of distinct distances determined by a set of $n$ points on a constant-degree two-dimensional algebraic variety $V$ (i.e., a surface) in $\mathbb R^3$ is at least $\Omega\left(n^{7/9}/{\rm polylog}…

Combinatorics · Mathematics 2016-04-07 Micha Sharir , Noam Solomon

We obtain new upper and lower bounds on the number of unit perimeter triangles spanned by points in the plane. We also establish improved bounds in the special case where the point set is a section of the integer grid.

Combinatorics · Mathematics 2025-10-06 Ritesh Goenka , Kenneth Moore , Ethan Patrick White

We study fundamental block-structured integer programs called tree-fold and multi-stage IPs. Tree-fold IPs admit a constraint matrix with independent blocks linked together by few constraints in a recursive pattern; and transposing their…

Computational Complexity · Computer Science 2024-02-28 Christoph Hunkenschröder , Kim-Manuel Klein , Martin Koutecký , Alexandra Lassota , Asaf Levin

In recent years, sum-product estimates in Euclidean space and finite fields have been studied using a variety of combinatorial, number theoretic and analytic methods. Erdos type problems involving the distribution of distances, areas and…

Combinatorics · Mathematics 2008-03-31 David Covert , Derrick Hart , Alex Iosevich , Doowon Koh , Misha Rudnev

We prove Pach-Sharir type incidence theorems for a class of curves in R^n and surfaces in R^3, which we call pseudoflats. In particular, our results apply to a wide class of generic irreducible real algebraic sets of bounded degree.

Combinatorics · Mathematics 2007-05-23 Izabella Laba , Jozsef Solymosi

We effectively bound T-singularities on non-rational projective surfaces with an arbitrary amount of T-singularities and ample canonical class. This fully generalizes the previous work for the case of one singularity, and illustrates the…

Algebraic Geometry · Mathematics 2024-04-10 Fernando Figueroa , Julie Rana , Giancarlo Urzúa

For elliptic systems with block structure in the upper half-space and t-independent coefficients, we settle the study of boundary value problems by proving compatible well-posedness of Dirichlet, regularity and Neumann problems in optimal…

Analysis of PDEs · Mathematics 2024-04-04 Pascal Auscher , Moritz Egert

This paper studies problems related to visibility among points in the plane. A point $x$ \emph{blocks} two points $v$ and $w$ if $x$ is in the interior of the line segment $\bar{vw}$. A set of points $P$ is \emph{$k$-blocked} if each point…

Combinatorics · Mathematics 2015-11-17 Greg Aloupis , Brad Ballinger , Sébastien Collette , Stefan Langerman , Attila Pór , David R. Wood

We generalize Siegel's theorem on integral points on affine curves to integral points of bounded degree, giving a complete characterization of affine curves with infinitely many integral points of degree d or less over some number field.…

Number Theory · Mathematics 2019-02-20 Aaron Levin

The master theorem, introduced by Richter-Gebert and generalized by Fomin and the first author, provides a method for proving incidence theorems of projective geometry using triangular tilings of surfaces. We investigate which incidence…

Combinatorics · Mathematics 2026-03-31 P. Pylyavskyy , M. Skopenkov

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 develop the methods used by Rudnev and Wheeler to prove an incidence theorem between arbitrary sets of M\"{o}bius transformations and point sets in $\mathbb F_p^2$. We also note some asymmetric incidence results, and give applications of…

Combinatorics · Mathematics 2022-11-18 Audie Warren , James Wheeler

We sharpen and generalize the dimension growth bounds for the number of points of bounded height lying on an irreducible algebraic variety of degree $d$, over any global field. In particular, we focus on the affine hypersurface situation by…

Number Theory · Mathematics 2025-12-05 Raf Cluckers , Pierre Dèbes , Yotam I. Hendel , Kien Huu Nguyen , Floris Vermeulen

We obtain upper bounds, independent of the ambient dimension, for the number of realizable zero-nonzero patterns and (over ordered fields) sign conditions of a finite family of polynomials $\mathcal P$ restricted to an algebraic subset $V$…

Combinatorics · Mathematics 2026-01-05 Saugata Basu , Laxmi Parida

An automorphism group of an incidence structure I induces a tactical decomposition on I. It is well known that tactical decompositions of t-designs satisfy certain necessary conditions which can be expressed as equations in terms of the…

Combinatorics · Mathematics 2013-11-22 Anamari Nakic , Mario Osvin Pavcevic

We propose a framework for thinking about eccentricity in terms of blocks. We extend the familiar definitions of radius and center to blocks and verify that a central block contains all central points. We classify graphs into two types…

Combinatorics · Mathematics 2023-09-22 Margaret I. Doig