Quantum Fields and Physics Beyond the Standard Model

现代粒子物理学面临着一幅相互矛盾的图景。一方面，实验数据导致了对标准模型(SM)的非常精确的验证，包括2012年在大型强子对撞机(LHC)上发现了希格斯玻色子。另一方面，观测宇宙学的巨大量化进步表明，尽管SM取得了成功，但仍有许多东西无法在宇宙学尺度上解释，最突出的是暗物质。这样的经验谜题，与关于SM的其他结构性问题相结合，推动了多方向的进一步理论工作：分析寻找新物理的广泛渠道；同时更深入地探索SM的基本结构，以更好地了解其成功并开发对新制度的应用。这种双重视角推动了我的两个长期研究目标。 第一个长期目标是更好地了解宇宙中物质内容的起源。我目前的重点是超越标准模型的经验驱动物理的场景和探测通道，特别是暗物质。有证据表明，暗物质是隐藏(或暗)部分的一部分，与SM的耦合很弱。研究目标包括使用系统的有效场论技术来开发高精度和高光度实验，这些实验通常对比在高能对撞机上直接实现的更大范围的能量尺度间接敏感。要解决的问题包括如何探索低质量候选暗物质的可行参数空间，要么直接在地下实验室，使用中能固定目标实验和对撞机，要么间接通过宇宙学、银河系和恒星物理的观测；以及什么机制决定了宇宙中物质和反物质之间的残留不对称性(这需要新的“破坏CP的”相互作用)。 该计划的第二个长期目标旨在加深我们对量子(规范)场理论的理解，量子(规范)场理论是SM的基石。这不仅在基础层面上很重要，而且对于开发新的计算工具来描述热或非平衡状态下的物质也是重要的。所提出的研究的一个方面集中在有限温度下场论的实时动态行为，这种动态行为可以用流体动力学来描述。一个具体的目标是利用有效量子场论的工具，发展对流体动力学状态的场论理解。这有一系列潜在的应用，但一个重要的(激励)场景是QCD(强核相互作用的规范理论)的强相互作用动力学，在RHIC和LHC等实验中探索的碰撞重离子的区域。

Modern particle physics faces a conflicted picture. On one hand, experimental data has led to a remarkably precise verification of the `Standard Model' (SM), including the discovery of the Higgs boson at the Large Hadron Collider (LHC) in 2012. On the other hand, tremendous quantitative advances in observational cosmology show that, despite its success, there is much that the SM cannot explain on cosmological scales, most prominently dark matter. Such empirical puzzles, combined with other structural questions about the SM, motivate further theoretical work in multiple directions: to analyze a wide range of channels in search of new physics; and at the same time to explore and the primary structures of the SM in greater depth, to better understand its success and develop applications to new regimes. This dual perspective drives my two long-term research goals. The first long term goal is to better understand the origin of the matter content in the universe. My current focus is on scenarios and detection channels for empirically motivated physics beyond the Standard Model, specifically dark matter. Evidence points to a framework in which dark matter is part of a hidden (or dark) sector, weakly coupled to the SM. Research objectives include the use of systematic effective field theory techniques to exploit high precision and high luminosity experiments, which are often indirectly sensitive to a much wider range of energy scales than are directly achievable at high energy colliders. Questions to be addressed include how to explore the viable parameter space of low mass dark matter candidates, either directly in underground labs, using medium-energy fixed-target experiments and colliders, or indirectly through observations of cosmology, the galaxy, and stellar physics; and what mechanism determines the relic asymmetry between matter and antimatter in the universe (which requires new "CP-violating" interactions). The second long term goal of this program aims to further our understanding of quantum (gauge) field theories, the building blocks of the SM. This is important at both a foundational level, and also for developing new calculational tools to describe matter in thermal or non-equilibrium regimes. One aspect of the proposed research focuses on the real-time dynamical behaviour of field theories at finite temperature, which near equilibrium can be described using hydrodynamics. A specific objective is to develop the field theoretic understanding of the hydrodynamic regime, using the tools of effective quantum field theory. This has a range of potential applications, but an important (motivating) scenario is the strongly-interacting dynamics of QCD (the gauge theory of the strong nuclear interactions), in regimes that are explored in experiments such as RHIC and the LHC which collide heavy ions.