Some problems from set-theoretic topology - normality, D-spaces and homogeneity

集合论拓扑的一些问题 - 正态性、D 空间和同质性

• 批准号: RGPIN-2019-06356
• 负责人: Szeptycki, Paul
• 金额: $ 1.09万
• 依托单位: York University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714792
• 关键词: Some; problems; set; theoretic; topology

Since its establishment in the middle of the last century, the field of set-theoretic topology has stood on the boundary between to foundational areas of pure mathematics: General Topology and Set Theory. The language and theory of sets is, indeed, the setting in which all of mathematics is axiomatized and the language in which fundamental questions around logic, truth and consistency are formalized. Godel's incompleteness theorem tells us that any axiomatic foundation for mathematics will include statements independent of the axioms (i.e., neither provable nor refutable). And indeed, the first area of mathematics where important and natural open problems turned out to be independent was in Topology an area of mathematics with a geometric flavour that is fundamental basis for areas of mathematics such as Analysis. This phenomenon of independence results has turned out to be quite endemic, even quite recently arising in Physics (with the proof of the independence of the general spectral gap problem). Set-theoretic topology is still an area where the interplay between both areas give rise to advances and the development of techniques that have impact and applications to many other areas of mathematics. For example, many important combinatorial tools (e.g., forcing techniques, Ramsey theory, combinatorial principles extracted from Godel's constructible universe, etc) that were initially developed to solve problems arising from Topology then found applications in areas as diverse as Functional Analysis, Group Theory and combinatorics. In 2007, M. Hrusak and J. Moore compiled a list “Twenty problems in set-theoretic topology” the most important and long-standing open problems in the field. This list, which formed the introduction to the monograph, Open Problems In Topology, was in the spirit of Hilbert's famous 100 problems formulated at the ICM in 1900 and the more recent Clay Institute Millennial problems, which were meant to encourage the mathematical community to focus and collaborate on the most important and impactful open problems. My proposed program of study is organized around three connected problems highlighted in the Hrusak-Moore list. Mary Ellen Rudin's problem whether there is a ``small'' Dowker space and the problems of van Douwen: Are Lindelof regular spaces D-spaces? And is the continuum the a bound on the cellularity of compact homogeneous spaces? These problems have been open for many decades and underscore the fact that combinatorics lie at the heart of many fundamental questions about the structure of topological spaces. Moreover, the many surprising connections between these problems and other topological and set theoretic questions explain their importance in the field and their prominence on the Hrusak-Moore list. The solution of any of these three problems will involve the development of new techniques and ideas which are certain to find applications in the field and inevitably to other areas of mathematics.

自上个世纪中期建立以来，集合论拓扑学领域一直处于纯数学的两个基础领域：一般拓扑学和集合论之间。集合的语言和理论实际上是所有数学被公理化的背景，也是围绕逻辑、真理和一致性的基本问题被形式化的语言。哥德尔的不完备性定理告诉我们，数学的任何公理基础都将包括独立于公理的陈述（即，既不可证明也不可反驳）。事实上，第一个数学领域的重要和自然开放的问题原来是独立的是在拓扑数学领域的几何味道，是根本的基础领域的数学，如分析。这种独立结果的现象已经被证明是相当流行的，甚至最近在物理学中出现（证明了一般谱隙问题的独立性）。 集理论拓扑仍然是一个领域，这两个领域之间的相互作用引起了进步和技术的发展，对许多其他数学领域产生了影响和应用。例如，许多重要的组合工具（例如，强迫技术，拉姆齐理论，从哥德尔的可构造的宇宙中提取的组合原理等），最初是为了解决拓扑学所产生的问题而开发的，然后在泛函分析，群论和组合学等领域找到了应用。 2007年，M. Hrusak和J.摩尔编制了一份清单“二十问题集理论拓扑”最重要的和长期存在的开放问题领域。这份清单形成了专著《拓扑学中的开放问题》的导言，它的精神来自希尔伯特在1900年在ICM制定的著名的100个问题和最近的克莱研究所千禧年问题，这是为了鼓励数学界关注和合作最重要和最有影响力的开放问题。我提出的研究计划是围绕Hrusak-Moore列表中突出显示的三个相关问题组织的。玛丽艾伦鲁丁的问题是否有一个“小”Dowker空间和货车Douwen的问题：Lindelof正则空间是D-空间吗？连续统是紧致齐性空间胞腔的a界吗？这些问题已经公开了几十年，并强调了这样一个事实，即组合学是关于拓扑空间结构的许多基本问题的核心。 此外，这些问题与其他拓扑和集合论问题之间的许多令人惊讶的联系解释了它们在该领域的重要性以及它们在Hrusak-Moore列表中的突出地位。 这三个问题的任何一个的解决都将涉及到新技术和新思想的发展，这些技术和新思想肯定会在数学领域中得到应用，而且不可避免地会应用到数学的其他领域。