Particles, Fields and Spacetime

粒子、场和时空

• 批准号: ST/G000433/1
• 负责人: Paul Mansfield
• 金额: $ 289.75万
• 依托单位: Durham University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2008
• 资助国家: 英国
• 起止时间: 2008 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FG000433%2F1
• 关键词: Particles; Fields; Spacetime

Particle Physics is about to enter a new and crucial phase. The switching on of the Large Hadron Collider at CERN will enable us to examine experimentally many of the theoretical concepts that underly the standard model of particle physics and search for the deeper structures that are believed to unify the laws of physics. Quantum field theory is the mathematical language in which the standard model is expressed, and it treats particles as point-like objects. Only certain kinds of quantum field theories, known as gauge theories, are consistent in the four dimensional world we live in. These include, and are generalisations of, the theory of electrodynamics that describes light interacting with electric charge. To be able to interpret the results of experiments we need to be able to solve gauge theories, at least approximately. This is a hard problem, but one in which there has recently been very remarkable progress due to a convergence of ideas originally developed in quite disparate contexts for solving very different kinds of theories. A major thrust of the project will be to push this line of enquiry further so as to be able to more fully understand gauge theories and be able to compute their properties. Matter at large scales is dominated by gravity which is described by Einstein's theory of General Relativity. This governs the motion of planets, stars, galaxies, and the evolution of the Universe itself. Uniting General Relativity and the standard model of particle physics is the most important challenge facing theoretical physics. It is widely, though not universally, believed that string theory provides such a unification. String theory replaces the point-like particles of quantum field theory with extended objects whose different vibrational modes account for the different species of fundamental particles. It is this belief that leads to the expectation that supersymmetry, a property of all realistic string theories, plays a role in nature, and may well be discovered at the LHC. Showing how nature contrives to hide this property is another part of the project. String theory has also lead to many unexpected relations between different kinds of physical theories, most notably in the AdS/CFT correspondence which states equivalences between certain gravity theories and corresponding gauge theories, enabling us to solve difficult problems in one theory by studying simper ones in the other. We will use this to study problems in gravity that would otherwise be intractable and also model the properties of hadrons by gravity. We will also use another method for studying hadrons that is particularly appropriate to describing large numbers of them bound into nuclei or even neutron stars. This is based on effective field theories such as the Skyrme model which we will investigate numerically using computers. Being a theory of quantum gravity strings have many implications for cosmology, in particular they admit the possibility that what we see as the physical universe is only a low dimensional subspace called a brane, moving in a space of higher dimensions. We will continue the quest to find direct experimental and observational signatures that will test this scenario. Part of the proposed research is to apply the methods of theoretical physics to study problems in biology, for example the self-assembly of viruses into sometimes symmetrical shapes can be studied with the methods physicists use to understand the symmetries of fundamental particles, with a view to possibly controlling this process.

粒子物理学即将进入一个新的关键阶段。欧洲核子研究中心大型强子对撞机的启动将使我们能够通过实验检验粒子物理学标准模型基础上的许多理论概念，并寻找被认为统一物理定律的更深层次的结构。量子场论是表达标准模型的数学语言，它将粒子视为点状物体。只有特定种类的量子场论，即规范场论，在我们生活的四维世界中是一致的。这些理论包括描述光与电荷相互作用的电动力学理论，并且是电动力学理论的概括。为了能够解释实验结果，我们需要能够解出规范理论，至少是近似解。这是一个难题，但由于最初在完全不同的背景下发展起来的、用于解决各种不同理论的思想的趋同，最近在这个问题上取得了非常显著的进展。该项目的一个主要目标是进一步推动这一研究方向，以便能够更全面地理解规范理论，并能够计算它们的性质。物质在大尺度上受引力支配，这是爱因斯坦的广义相对论所描述的。这支配着行星、恒星、星系的运动，以及宇宙本身的演化。统一广义相对论和粒子物理学的标准模型是理论物理学面临的最重要的挑战。人们广泛地（虽然不是普遍地）相信弦理论提供了这样的统一。弦论用扩展的物体取代了量子场论中的点状粒子，而扩展的物体的不同振动模式解释了不同种类的基本粒子。正是这种信念导致了人们的期望，即超对称性（所有现实弦理论的一个属性）在自然界中发挥着作用，并且很可能在大型强子对撞机上被发现。展示大自然如何设法隐藏这种特性是该项目的另一部分。弦理论还在不同种类的物理理论之间产生了许多意想不到的关系，最显著的是AdS/CFT对应，它说明了某些引力理论和相应的规范理论之间的等价性，使我们能够通过研究一种理论中的简单问题来解决另一种理论中的困难问题。我们将用它来研究引力问题，否则将是棘手的，也模型的性质强子的引力。我们还将使用另一种方法来研究强子，这种方法特别适合于描述大量强子束缚在原子核甚至中子星中。这是基于有效场理论，如Skyrme模型，我们将使用计算机进行数值研究。作为一个理论的量子引力弦有许多影响宇宙学，特别是他们承认的可能性，我们所看到的物理宇宙只是一个低维子空间称为膜，运动在一个空间的更高的维度。我们将继续寻找直接的实验和观察特征，以测试这种情况。拟议的研究的一部分是应用理论物理学的方法来研究生物学中的问题，例如，可以用物理学家用来理解基本粒子的对称性的方法来研究病毒的自组装，有时是对称的形状，以期可能控制这一过程。

项目成果

On the absence of reflection in AdS 4/CFT 3

关于 AdS 4/CFT 3 中缺乏反映

• DOI: 10.1007/jhep01(2010)129
• 发表时间: 2010
• 期刊: Journal of High Energy Physics
• 影响因子: 5.4
• 作者: Ahn C

Coupling M2-branes to background fields

将 M2 膜耦合到背景场

• DOI: 10.1007/jhep08(2011)078
• 发表时间: 2011
• 期刊: Journal of High Energy Physics
• 影响因子: 5.4
• 作者: Allen J

On the absence of reflection in AdS4/CFT3

关于 AdS4/CFT3 中缺少反射的问题

• DOI: 10.48550/arxiv.0910.5584
• 发表时间: 2009
• 作者: Ahn C

Boundary conditions for scalars in Lifshitz

• DOI: 10.1088/0264-9381/30/6/065009
• 发表时间: 2012-12
• 期刊: Classical and Quantum Gravity
• 影响因子: 3.5
• 作者: T. Andrade;S. Ross

States of a chiral 2D CFT

• DOI: 10.1088/0264-9381/28/4/045004
• 发表时间: 2010-11
• 期刊: Classical and Quantum Gravity
• 影响因子: 3.5
• 作者: V. Balasubramanian;Jamie Parsons;S. Ross