RUI: Precision Cosmological Tests of Varying Fundamental Constants

该奖项资助哈弗福德学院丹尼尔·格林教授的研究活动。我们正处于精确宇宙学的时代，对古代光（所谓的“宇宙微波背景”）的测量已经得出了一个共识，即宇宙的内容包括神秘的暗物质和暗能量。理解暗物质和暗能量的最佳框架涉及理论粒子物理学中的新思想，这意味着自然的基本“常数”实际上在空间和时间上是变化的。格林教授将开发新的方法来测试这些场景，使用来自宇宙微波背景以及其他预期的未来测量的数据。这样的研究通过加强美国的基础科学来服务于国家利益。这项工作还将产生更广泛的重大影响。PI将监督本科研究，并领导课程规划，以促进第一代和低收入学生在物理课程和研究中的代表性和参与。从技术上讲，PI将探索超越标准模型的场景（基于弦启发模型），其中精细结构常数和电子质量是动态变量而不是常数。这项工作的动机是对高红移类星体的令人费解的观察。PI将在这些模型中计算宇宙微波背景统计，发展相关的微扰理论，在新的宇宙玻尔兹曼码中实现它，开发新的统计方法，获得约束条件，并为未来的地面实验工作进行预测。这项工作将应用于计算这些模型的非高斯映射特征，用当前数据对这些现象进行预测和可能的测试。PI还将确定不同的基本参数模型对观测中性氢的高红移21厘米发射线的影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award funds the research activities of Professor Daniel Grin at Haverford College.We are in the era of precision cosmology, where measurements of ancient light (the so-called "cosmic microwave background") have yielded a consensus picture in which the contents of the universe include mysterious dark matter and dark energy. The best framework for understanding dark matter and dark energy involves new ideas in theoretical particle physics which imply that the fundamental ‘constants’ of nature actually vary in space and time. Professor Grin will develop new methods of testing these scenarios, using data from the cosmic microwave background as well as from other anticipated future measurements. Such research serves the national interest by strengthening fundamental science within the United States. This work will also have significant broader impacts. The PI will supervise undergraduate research and lead curricular programming that promotes the representation and participation of first-generation and lower-income students in physics courses and research.More technically, the PI will explore beyond-the-standard-model scenarios (based on string-inspired models) in which the fine-structure constant and electron mass are dynamical variables rather than constants. The work is motivated by puzzling observations of high-redshift quasars. The PI will compute cosmic microwave background statistics in these models, developing the relevant perturbation theory, implementing it in new cosmological Boltzmann codes, developing new statistical methods, obtaining constraints, and conducting forecasts for future ground-based experimental efforts. This work will be applied to compute the non-Gaussian map signatures of these models, conducting forecasts and possibly tests for such phenomena with current data. The PI will also determine the impact of varying fundamental parameter models on observations of the high-redshift 21-cm emission line from neutral hydrogen.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.