Analytic and Algebraic Methods in Discrete Geometry

离散几何中的解析和代数方法

• 批准号: 1953946
• 负责人: Zilin Jiang
• 金额: $ 15万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1953946&HistoricalAwards=false
• 关键词: Analytic; Algebraic; Methods; Discrete; Geometry

This award supports the PI's research in building mathematical tools to solve combinatorial problems in Discrete Geometry. Discrete geometry studies fundamental geometric objects, such as points, lines and circles, and their combinatorial properties. Thus most combinatorial problems in Discrete Geometry are quite visual and can be presented in a simple manner: What is the minimum total width of strips that cover a unit disk in the plane? Or, what is the maximum number of lines through the origin pairwise separated by the same angle? In contrast to the simple appearances of these problems, many of these problems, including the ones considered in this project, remain unsolved for an extended period or have been partly solved only recently following great efforts. This project aims to further develop the toolbox of available approaches, most of which are analytic or algebraic in nature. Simultaneously, the project integrates these research problems and themes into educational and outreach activities that extend from the high school level to the graduate.The first topic of this project concerns extensions and variations of Tarski's plank problem: How to efficiently cover a convex body in the plane using planks? Generalizations of Tarski’s plank problem are central to geometric analysis and convex geometry, and continue to generate interest in the geometric and analytic aspects of coverings of a convex body. The second topic concerns equiangular lines —- a collection of lines through the origin pairwise separated by the same angle. Investigation of the equiangular lines problem turns out to be fruitful and unearthed many challenging problems in algebraic graph theory. Solutions to some problems have practical consequences in Operational Research, Quantum Computation and Communication Theory. Previous foundational work, including some done by the PI, has shown that tools and insights from Ramsey Theory, Extremal Combinatorics, Probabilistic Methods, Spectral Graph Theory, Algebraic Combinatorics, Topological Combinatorics, and Algebraic Geometry can be helpful in solving the problems in this project.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项支持PI在构建数学工具以解决离散几何组合问题方面的研究。离散几何研究基本的几何对象，如点、线和圆，以及它们的组合性质。因此，离散几何中的大多数组合问题都是非常直观的，并且可以以简单的方式呈现：在平面上覆盖单位圆盘的条带的最小总宽度是多少？或者，通过原点以相同角度成对分开的线的最大数量是多少？与这些问题的简单表象相反，其中许多问题，包括本项目中考虑的问题，长期以来一直没有得到解决，或者只是在最近经过巨大努力才得到部分解决。该项目旨在进一步开发现有方法的工具箱，其中大多数是分析或代数性质的。同时，该项目将这些研究问题和主题整合到从高中到研究生的教育和推广活动中。该项目的第一个主题涉及塔斯基木板问题的扩展和变化：如何有效地使用木板覆盖平面上的凸体？塔斯基木板问题的推广是几何分析和凸几何的核心，并继续在凸体覆盖的几何和分析方面产生兴趣。第二个主题涉及等角线--通过原点的两两以相同角度分开的线的集合。等角线问题的研究取得了丰硕的成果，并在代数图论中发现了许多具有挑战性的问题。一些问题的解决方案在运筹学、量子计算和通信理论中具有实际意义。以前的基础工作，包括PI所做的一些工作，已经表明，来自拉姆齐理论，极值组合学，概率方法，谱图论，代数组合学，拓扑组合学，该奖项反映了NSF的法定使命，并通过使用基金会的智力价值进行评估，更广泛的影响审查标准。

项目成果

An Isoperimetric Inequality for Hamming Balls and Local Expansion in Hypercubes

汉明球的等周不等式和超立方体的局部膨胀

• DOI: 10.37236/9860
• 发表时间: 2022
• 期刊: The Electronic Journal of Combinatorics
• 作者: Jiang, Zilin;Yehudayoff, Amir
• 通讯作者: Yehudayoff, Amir

Rainbow Odd Cycles

彩虹奇数周期

• DOI: 10.1137/20m1380557
• 发表时间: 2021
• 期刊: SIAM Journal on Discrete Mathematics
• 影响因子: 0.8
• 作者: Aharoni, Ron;Briggs, Joseph;Holzman, Ron;Jiang, Zilin
• 通讯作者: Jiang, Zilin