Collaborative Research: Combining Galaxy and Cosmic Microwave Background Surveys for Precise and Robust Constraints on Cosmology

合作研究：结合星系和宇宙微波背景调查对宇宙学进行精确和稳健的约束

• 批准号: 2306166
• 负责人: Chihway Chang
• 金额: $ 25.19万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2306166&HistoricalAwards=false
• 关键词: Collaborative; Research; Combining; Galaxy; Cosmic

The distribution of matter throughout the cosmos carries information about the origin, future, and composition of the Universe. However, obtaining high-precision measurements of the matter distribution is challenging: most of the matter is in the form of invisible dark matter, making it impossible to observe directly. Instead, techniques such as gravitational lensing – the bending of light by gravity – must be used to infer where the matter is. With this research program, scientists at the University of Hawaii and the University of Chicago will analyze four different and highly complementary probes of the matter distribution from state-of-the-art astronomical surveys to obtain precise and unbiased constraints on the properties of the Universe. The team will use measurements of galaxy positions and gravitational lensing of galaxies from the Dark Energy Survey (DES), measurements of gravitational lensing of light from the cosmic microwave background (CMB) by the South Pole Telescope (SPT) and the Atacama Cosmology Telescope (ACT), and finally, measurements from SPT and ACT of the scattering of CMB light with electrons. By analyzing these complementary probes in concert, the team will reduce uncertainties on the properties of the Universe, minimize potential biases in their constraints, and obtain a more complete picture of the matter distribution. This award will additionally support development of new teaching modules designed to give high school and undergraduate students the opportunity to learn from real data and gain hands-on experience in data science. Statistics of the matter distribution are predicted by the cosmological constant and cold dark matter (LCDM) model, and comparing these predictions to observations is a key goal of current and future cosmic surveys. Recently, measurements of the late-time matter distribution from galaxy surveys have shown hints of disagreement with extrapolations of early-Universe measurements that assume LCDM. This disagreement could result from fundamental problems with LCDM, or from systematic uncertainties impacting the measurements. Using new data from DES, SPT, and ACT, the team will measure and analyze cross-correlations between CMB lensing, galaxy positions, galaxy lensing, and the thermal Sunyaev Zel'dovich effect in order to perform a definitive assessment of tension with LCDM, test alternative cosmological models, and enable improved constraints with future surveys. The broader impacts of the proposal will be to provide training in data science to high school, undergraduate and graduate students, and to increase public engagement with astronomical surveys. The PIs will develop a set of new teaching tools based on Python notebooks that give high school and undergraduate students the opportunity to learn from real data. These teaching tools will be implemented in classrooms in Honolulu and Chicago.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.

整个宇宙中的物质分布携带着有关宇宙起源、未来和组成的信息，然而，获得物质分布的高精度测量具有挑战性：大多数物质都是不可见的暗物质的形式，这使得它成为可能。相反，必须使用引力透镜（重力使光弯曲）等技术来推断物质的位置，夏威夷大学和芝加哥大学的科学家将分析四种不同的物质。和高度互补的物质探针该团队将使用来自暗能量巡天（DES）的星系位置测量和星系引力透镜测量来获取对宇宙特性的精确和公正的约束。南极望远镜（SPT）和阿塔卡马宇宙学望远镜（ACT）对来自宇宙微波背景（CMB）的光进行了测量，最后，对南极望远镜（SPT）和阿塔卡马宇宙学望远镜（ACT）进行了测量通过协同分析这些互补探针，该团队将减少宇宙特性的不确定性，最大​​限度地减少其约束中的潜在偏差，并获得更完整的物质分布图。开发新的教学模块，旨在让高中生和本科生有机会从真实数据中学习并获得数据科学的实践经验，通过宇宙常数和冷暗物质（LCDM）模型预测物质分布的统计数据，并将这些预测与观察结果进行比较是当前和未来宇宙调查的一个关键目标，最近，对星系调查的晚期物质分布的测量显示出与假设 LCDM 的早期宇宙测量的推断不一致的迹象，这种不一致可能是由于 LCDM 的基本问题造成的。或来自影响测量的系统不确定性，该团队将使用来自 DES、SPT 和 ACT 的新数据来测量和分析 CMB 透镜、星系位置、星系透镜和热 Sunyaev Zel'dovich 效应之间的互相关性。为了对 LCDM 的紧张关系进行明确的评估，测试替代宇宙学模型，并改善未来调查的约束，该提案的更广泛影响将是为高中生、本科生和研究生提供数据科学培训。 PI 将开发一套基于 Python 笔记本的新教学工具，让高中生和本科生有机会从真实数据中学习。这些教学工具将在檀香山和芝加哥的教室中实施。奖项反映通过使用基金会的智力价值和更广泛的影响审查标准进行评估，NSF 的法定使命被认为值得支持。