RUI: Supersymmetric Gauge Theory and Dirichlet-Branes

该项目的主要目的是探索描述两种不同基本力--核力和引力--的理论之间的联系。强核力和弱核力用规范理论来描述，而量子引力被认为用弦理论来描述。然而，弦理论不仅包含弦，还包含D-膜，即其性质涉及超对称规范理论的扩展对象，因此提供了这两种理论之间的联系。具体地说，该项目专注于包含D-膜和定向折面的特定弦理论的性质；在这些理论中，描述D-膜的超对称规范理论包括夸克的类似物。这一研究方向的兴趣在于，在一种理论中不可能回答的问题可能很容易用另一种理论来回答，反之亦然，从而使这两种理论都能取得进展。例如，规范理论的广为人知的性质可能有助于更好地理解弦理论，从而更好地理解量子引力，而量子引力长期以来一直是一个悬而未决的问题。相反，弦理论可以用来探索人们所知甚少的强耦合区域中的规范理论。最终，这可以解释夸克禁闭现象(即无法观察到自由夸克的事实)，并根据组成夸克的性质对质子、原子核等的结构有一个定量的理解。

The primary aim of the project is to explore connections between theories describing two different fundamental forces, namely, the nuclear force and gravity. The strong and weak nuclear forces are described by gauge theories, whereas quantum gravity is thought to be described by string theory. String theory, however, contains not only strings but also D-branes, extended objects whose properties involve supersymmetric gauge theories, thus providing the connection between the two types of theory. Specifically, the project focuses on the properties of particular string theories containing D-branes and orientifold planes; in these theories, the supersymmetric gauge theories describing the D-branes include the analogs of quarks.The interest of this line of research is that questions impossible to answer in one theory may be easy to answer using the other theory, and vice versa, allowing progress to be made in both. For example, well-understood properties of gauge theory could lead to a better understanding of string theory, and thus quantum gravity, which has long been an unsolved problem. Conversely, string theory could be used to probe gauge theories in the poorly understood strong-coupling regime. Ultimately, this could explain the phenomenon of quark confinement (that is, the fact that free quarks cannot be observed) and yield a quantitative understanding of the structure of protons, nuclei, etc., in terms of the properties of their constituent quarks.