论文标题
组合细胞复合物:二元性,重建和因果关系
Combinatorial Cell Complexes: Duality, reconstruction and causal cobordisms
论文作者
论文摘要
本文提出了一个基于组合细胞复合物(CC)概念的框架,其细胞被简单地定义为有限的顶点集。 CC的单元格受到四个公理的约束,涉及一个级别函数,该级别函数将秩(或维度)分配给每个单元格。我们的框架着重于CC的类别,该类别承认包容性双重性图。我们介绍了一种cobordism的组合概念,该概念使我们能够挑出一个类别,其形态是具有因果关系结构的恢复性。我们的目的是提供一种方法,以寻找一种量子场理论的组合概念,其内置二元性操作作用于基础空间,而不是依靠任何流形结构。引言包括与与量子重力相关的理论和数学物理学领域的联系并激励我们的框架。我们首先在CC上引入CC和二重性图,该类别的CC带有空的边界称为封闭CC。然后,我们专注于从等级2和较低的细胞重建特定类别的CC的问题。此类CC特别是对没有边界的简单络合物的双重偶,并且使用离散的连接概念实现了它们的重建。我们的下一个主要结果将我们在封闭CC上定义的二元性图扩展到具有边界的一类CC。该扩展二元图的研究的一个重要副产品是该工作中使用的共同体的组合概念。我们还通过称为还原的地图以及称为倒塌的双重概念引入了CC对CC细分的一般概念。这两种类型的地图使用称为切片序列的序列,表征了某些CC的结构,称为切片。切片是我们对因果关系的定义的基本建筑集团,而切片序列的双重二元定义了恢复性的组成,从而为我们提供了一种类别,其形态是因果关系。
This thesis proposes a framework based on a notion of combinatorial cell complex (cc) whose cells are defined simply as finite sets of vertices. The cells of a cc are subject to four axioms involving a rank function that assigns a rank (or a dimension) to each cell. Our framework focuses on classes of cc admitting an inclusion-reversing duality map. We introduce a combinatorial notion of cobordism that allows us to single out a category whose morphisms are cobordisms having a causal structure. Our aim is to offer an approach to look for a combinatorial notion of quantum field theory having a built-in duality operation acting on the underlying space and not relying on any manifold structure. The introduction includes links with fields in Theoretical and Mathematical Physics related to Quantum Gravity and motivating our framework. We start by introducing cc and the duality map on a class of cc with empty boundary called closed cc. We then focus on the problem of reconstructing a certain class of cc from their cells of rank 2 and lower. Such cc are in particular duals to simplicial complexes with no boundary and their reconstruction is realized using a discrete notion of connection. Our next main result extends the duality map we defined on closed cc to a class of cc with boundary. An important by-product of the study of this extended duality map is the combinatorial notion of cobordism used in this work. We also introduce a general notion of subdivision of a cc via a map called reduction, as well as the dual notion of reduction called collapse. These two types of map characterize the structure of certain cc called slices, using sequences of maps called slice sequences. Slices are the basic building blocs of our definition of causal cobordisms and the dual of a slice sequence defines the composition of cobordisms, providing us with a category whose morphisms are causal cobordisms.