The Physics and Cosmology of Dark Matter, Dark Energy, and the Early Universe

我们对超越粒子物理标准模型的新物理，新的基本粒子和场的最好证据，来自于宇宙学观测。这一提议旨在从理论和实验上探索和约束暗物质、暗能量和早期宇宙的物理学。我们相信暗物质--宇宙中85%的物质--不是原子物质。人们对其粒子性质知之甚少，大型强子对撞机和其他实验的无效结果严重限制了暗物质的长期预测模型，如最轻的超对称伙伴。这激发了探索理解暗物质物理的新途径，我们建议以一种通用的方式描述暗物质物理对宇宙学和天体物理可观测性的影响。特别是，如果暗物质与其他粒子或其自身相互作用，或者是相对论产生的，宇宙微扰就会以精确和可计算的方式进行修正。CMB、大尺度结构和银河系物质分布为暗物质粒子物理提供了关键的实验约束。我们将扩展现有的工作，在一类将暗物质与相对论粒子或其自身相耦合的理论中，对初始暗物质的分布做出精确的预测。这使得可以进行自洽的模拟，可以用来计算暗物质物理对宇宙学和银河系结构形成的影响。暗能量正在推动宇宙的加速膨胀，但造成这一现象的物理原因尚不清楚。一个微小的宇宙常数与理论预测(宇宙常数问题)完全冲突，不存在令人信服的理论替代方案。对宇宙膨胀历史的新测量可能会为暗能量的起源提供线索。加拿大氢强度图实验(CHME)是一项由CFI资助的暗能量实验，旨在测量具有21厘米氢线的宇宙的膨胀率。CHINE正在建设中，这项提议旨在开发强大的方法来拒绝虚假的前景污染，并找到有效的方法来创建数据产品，这些数据产品将为暗能量物理模型提供前沿约束。*宇宙早期发生的类似膨胀的现象，产生了在宇宙中观察到的初始曲率波动。可行的膨胀模型预测了近乎高斯的波动，而非高斯修正揭示了场相互作用的强度和形式。这些非高斯特征在宇宙的大尺度结构中以非常不同的方式表现出来，我们建议量化探索宇宙前所未有的大量体积的实验，如CHAME，如何约束非高斯统计数据和膨胀的理论模型。

Our best evidence for new physics beyond the standard model of particle physics, new fundamental particles and fields, arises from cosmological observables. This proposal aims to explore and constrain, theoretically and experimentally, the physics of dark matter, dark energy, and the early universe. ******We are confident dark matter -- 85% of all matter in the Universe -- is something other than atomic matter. Precious little is known about its particle properties and null results from the Large Hadron Collider and other experiments have severely constrained long-heralded models for dark matter like the lightest supersymmetric partner. This motivates exploring new pathways for understanding the physics of dark matter and we propose to characterize in a generic way the impact of dark matter physics on cosmological and astrophysical observables. In particular, if dark matter interacts with other particles or itself, or is produced when relativistic, cosmological perturbations are modified in precise and calculable ways. The CMB, large-scale structure, and galactic matter distributions provide key experimental constraints on dark-matter particle physics. We will extend our existing work to make precise predictions of the initial dark matter distribution in a whole class of theories that couple dark matter to relativistic particles or themselves. This allows for self-consistent simulations to be made that can be used to calculate the impact of dark-matter physics on cosmological and galactic structure formation.******Dark energy is driving the accelerated expansion of the Universe, but the physics responsible for this is unknown. A miniscule cosmological constant is in stark conflict with theoretical predictions (the cosmological constant problem) and no compelling theoretical alternatives exist. New measurements of the expansion history of the Universe may give clues to the origin of dark energy. The Canadian Hydrogen Intensity Mapping Experiment (CHIME) is a CFI-funded dark energy experiment designed to measure the expansion rate of the Universe with the 21-cm line of hydrogen. CHIME is under construction and this proposal aims to develop robust methods to reject spurious foreground contamination and find efficient ways to create data products that will provide cutting edge constraints on models of dark energy physics.******Something like inflation occurred in the early universe to generate the initial curvature fluctuations observed in the cosmos. Viable models of inflation predict nearly Gaussian fluctuations and non-Gaussian corrections reveal the strength and form of field interactions. These non-Gaussian features manifest themselves in highly distinct ways in the large-scale structure of the Universe and we propose to quantify how experiments probing unprecedentedly large volumes of the Universe, like CHIME, can constrain non-Gaussian statistics and theoretical models of inflation.**