Quantum field theories of the dark universe

粒子物理学和宇宙学标准模型的成功是前所未有的。总之，它们能够解释我们从最小尺度上的亚原子粒子的动力学和相互作用到最大尺度上的宇宙演化的观测结果。然而，重要的问题仍然没有答案。已知的粒子物理学只描述了宇宙可见的5%。为了解释星系是如何形成的，以及恒星和组成它们的气体是如何运动的，我们需要暗物质。为了解释为什么遥远的星系正在加速远离我们，我们需要暗能量。这个“暗宇宙”的本质仍然是一个谜，揭开它的秘密是基础物理学中最重要和最具挑战性的问题之一。此外，标准模型无法解释物质如何支配反物质，留下5%的可见物质。更糟糕的是，对已知最重的基本粒子--希格斯玻色子和顶夸克--的质量测量表明，我们的宇宙可能处于一种不稳定状态，可能会衰变成一种与量子理论预测截然不同的灾难性状态。为了解决这些问题并解释暗宇宙的性质，我们必须修改粒子物理学的标准模型或爱因斯坦的引力理论，或者两者都有。我的目标正是通过引入由“标量场”描述的新粒子来做到这一点，这些粒子会产生新的自然力。一旦直接耦合到引力，或者等价地耦合到希格斯玻色子，这些“标量-张量理论”就会对它们局部环境的密度变得敏感。这使它们能够逃避我们太阳系的引力测试，但仍然在宇宙的其他地方产生新的力量，提供了丰富的行为和描述暗宇宙的潜力。此外，新的标量场可以解决我们粒子物理学模型中的弱点，有助于稳定我们宇宙的状态或改变早期宇宙的热等离子体演化的方式。我将开发新的理论工具，用支撑基础物理学（称为量子场论）的严格数学框架来对抗这些模型。这将使我能够解决阻碍我们对实验和观察做出准确预测的关键理论不确定性。我的研究将最终确定基于额外标量粒子的暗宇宙模型是否可以解释宇宙的观测内容和演化，同时经得起实验作为已知粒子物理学的一致扩展。我将在诺丁汉大学建立一个国际领先的研究小组，以其粒子宇宙学小组为基础，该中心拥有天体物理学和宇宙学领域的广泛和互补的专门知识，这将使本方案受益。其他合作者将包括大学天文学和量子引力小组的成员，以及来自英国和海外其他领先研究机构的理论和实验方面的知名研究人员，包括达勒姆大学粒子物理现象学研究所和欧洲核子研究中心。我将利用现有的和未来的粒子物理实验数据，如欧洲核子研究中心的大型强子对撞机;地面和卫星观测站，如暗能量调查和LIGO引力波观测站;从量子测量技术的实验中寻找新的自然力量。我的计划将开创一种新的跨学科方法来研究暗宇宙，这同时挑战了理论模型与数据的经验一致性以及量子理论中的数学一致性。它要么排除这些模型，要么提供一个可行的模型目录，沿着可靠的预测，这将有助于指导未来的实验和观测工作，以揭开暗宇宙的奥秘。

The successes of the Standard Models of particle physics and cosmology have been unprecedented. Together, they are able to explain our observations from the dynamics and interactions of subatomic particles on the smallest scales to the evolution of the Universe on its largest scales. However, important questions remain unanswered.Known particle physics describes only the visible 5% of the Universe. To explain how galaxies formed, and how the stars and gas that they are made of move, we need dark matter. To explain why distant galaxies are accelerating away from us, we need dark energy. The nature of this "dark universe" remains a mystery, and unravelling its secrets is one of the most important and challenging problems in fundamental physics.In addition, the Standard Models cannot explain how matter came to dominate over antimatter to leave behind the 5% of visible matter. Worse still, measurements of the masses of the heaviest known elementary particles - the Higgs boson and top quark - indicate that our universe may reside in an unstable state that could decay to a catastrophically different one due to the predictions of quantum theory.To resolve these problems and to explain the nature of the dark universe, we must modify the Standard Model of particle physics or Einstein's theory of gravity, or both.I aim to do precisely this by introducing new particles described by "scalar fields", which give rise to new forces of nature. Once coupled directly to gravity or, equivalently, to the Higgs boson, these "scalar-tensor theories" become sensitive to the density of their local environment. This allows them to evade tests of gravity in our Solar System but still produce new forces elsewhere in the universe, providing a rich array of behaviours and the potential to describe the dark universe. Moreover, new scalar fields can resolve the weaknesses in our model of particle physics, helping to stabilise the state of our universe or change the way that the hot plasma of the early universe evolved.I will develop new theoretical tools to confront these models with the full rigour of the mathematical framework that underpins fundamental physics known as quantum field theory. This will allow me to address key theoretical uncertainties that are preventing us from making accurate predictions for experiment and observation. My research will determine definitively whether models of the dark universe based on extra scalar particles can explain the observed content and evolution of the Universe, while standing up to experiment as consistent extensions of known particle physics.I will establish an internationally leading research group at the University of Nottingham, based within its Particle Cosmology Group, which is home to extensive and complementary expertise in areas of astrophysics and cosmology that will benefit this programme. Additional collaborators will include members of the University's Astronomy and Quantum Gravity Groups, and renowned researchers in theory and experiment from other leading research institutions in the UK and overseas, including the Institute for Particle Physics Phenomenology at Durham University and CERN. I will exploit existing and future data from particle-physics experiments, such as those at CERN's Large Hadron Collider; from ground-based and satellite observatories, such as the Dark Energy Survey and the LIGO gravitational-wave observatory; and from experiments using quantum measurement techniques to look for new forces of nature.My programme will pioneer a novel interdisciplinary approach to the dark universe, which simultaneously challenges theoretical models on their empirical consistency with data and their mathematical consistency within quantum theory. It will either rule these models out or provide a catalogue of viable ones, along with reliable predictions that will help to guide future experimental and observational efforts to uncover the mysteries of the dark universe.