M-branes, noncommutative geometry and thermodynamics of charged rotating (A)dS spacetimes with a NUT twist

物理学中最有趣和最吸引人的问题之一是如何理解引力的量子理论。我的长期研究涉及加强和增加我们的粒子和引力物理学的知识，从粒子物理学，非对易几何学和引力物理学的角度考虑与量子引力有关的具体问题。根据我们目前的知识，量子引力理论的最佳候选理论是超弦理论，它似乎表现出良好的微扰行为。在超弦理论中，粒子物理学中的所有基本粒子和自然界中所有已知的力都是最基本的物体（一维弦）的不同状态的实现。然而，一段时间以来，人们已经知道至少有五种不同的相容超弦理论。看起来它们只是以某种对偶关系存在，尽管没有已知的理论解释为什么不同的超弦理论之间可以有对偶关系。在这方面，很难确定哪一种特定的弦理论描述了我们的真实的世界。非微扰弦理论的最新发展--从超弦理论中各种扩展对象（狄利克雷膜）的发现开始--已经开始阐明这个重要问题。很明显，这些扩展对象在超弦的强动力学和膜理论（M理论）中起着非常重要的作用。在强耦合极限下，超弦理论不仅仅是弦的理论，而是包含许多作为轻自由度的扩展对象（膜）。这些天体的存在，被证明是不同超弦理论之间对偶关系的起源。目前所称的M理论，是一个关于许多扩展对象的11维量子理论，这些扩展对象在其微扰真空周围产生了所有的超弦理论。在这方面，我的研究计划将解决当前的问题，在粒子物理学，非对易几何和引力物理学的启发弦理论。

One of the most interesting and attractive problems in physics is that of understanding how to make sense of a quantum theory of gravity. My long-term research involves strengthening and increasing our knowledge of particle and gravitational physics by considering specific questions connected with quantum gravity from the viewpoints of particle physics, noncommutative geometry and gravitational physics. According to our present knowledge, the best possible candidate theory for a quantum theory of gravity is superstring theory, which seems to exhibit good perturbative behaviours. In superstring theory, all the fundamental particles in particle physics and all known forces in nature are realizations of different states of the most fundamental object that is a one-dimensional string. However it has been known for some time that there are at least five distinct consistent superstring theories. It seemed that they simply exist with some dual relations between them although there was no known theory that explained why different superstring theories could have dual relations between them. In this regard, it was very difficult to determine which particular string theory describes our real world. Recent developments in non-perturbative string theory -- starting with the discovery of various extended objects in superstring theories (Dirichlet branes) -- have begun to cast light on this important question. It has become clear that these extended objects play very important roles in the strong dynamics of superstrings and in Membrane theory (M-theory). Superstring theories, when viewed in the strong coupling limit, are not just theories of strings but instead contain many extended objects (branes) as light degrees of freedom. The existence of these objects turned out to be the origin of the dual relations between different superstring theories. M-theory as it is called at present, is an eleven dimensional quantum theory of the many extended objects which produce all the superstring theories around its perturbative vacua. In this context my research plan will address current issues in particle physics, noncommutative geometry and gravitational physics that are inspired by string theory.