Unveiling the growth of structure in the Dark Universe

揭示黑暗宇宙中结构的生长

• 批准号: EP/Y03015X/1
• 负责人: Benjamin Joachimi
• 金额: $ 245.42万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY03015X%2F1
• 关键词: Unveiling; growth; structure; Dark; Universe

The accelerated expansion of the Universe in recent cosmic times is one of the most important unexplained observations in modern physics. It has profound implications in that the cosmos could be permeated by a new, exotic matter component known as dark energy, or that one of the most successful theories of physics, Einstein's general relativity, breaks down on cosmological scales.Emerging tensions between measurements in the late and early Universe are tantalising signs of a potential paradigm change away from the current cosmological standard model. The most promising route to shedding light on this key open problem is to explore the cosmic large-scale structure with multiple probes extracted from large galaxy surveys. I will map the growth of fluctuations in the matter distribution over an unprecedentedly wide range of cosmic history at per-cent level precision, enabling decisive conclusions on cosmic tensions and broad classes of alternative cosmological models. To this end, I will exploit two of the leading galaxy surveys of the decade, which are about to start delivering data: the ESA Euclid space mission and the DESI project, the largest spectroscopic galaxy survey ever undertaken. I will employ combined measurements of the clustering of galaxies, the gravitational lensing effect ongalaxies, as well as the spatial distribution of quasars and of imprints of large-scale structure in their spectra. The joint analysis in overlapping cosmic volumes ensures a maximum of robust constraints on cosmology and on the astrophysical processes that link galaxies to the underlying dark matter distribution. The fidelity of results is advanced through dedicated calibration measurements pushed far beyond the state of the art, and by abandoning the conventional data analysis in favour of a novel forward-modelling approach via fast, highly multiplexed simulations and machine learning-assisted inference techniques.

在近代宇宙时代，宇宙的加速膨胀是现代物理学中最重要的无法解释的观测之一。它具有深远的意义，因为宇宙可能被一种被称为暗能量的新的奇特物质成分所渗透，或者最成功的物理学理论之一爱因斯坦的广义相对论在宇宙尺度上失效。在宇宙晚期和早期测量之间出现的紧张关系是当前宇宙标准模型的潜在范式变化的诱人迹象。解开这个关键问题的最有希望的途径是用从大型星系调查中提取的多个探测器来探索宇宙的大尺度结构。我将以百分之百的精度绘制宇宙历史上空前广泛的物质分布波动的增长图，从而对宇宙张力和各种不同的宇宙模型作出决定性的结论。为此，我将利用这十年来两个领先的星系调查，它们即将开始提供数据：欧几里得太空任务和DESI项目，这是有史以来最大的光谱星系调查。我将对星系的群集、星系的引力透镜效应、类星体的空间分布以及类星体光谱中大规模结构的印记进行综合测量。在重叠的宇宙体积中进行联合分析，确保了对宇宙学和天体物理过程的最大约束，这些过程将星系与潜在的暗物质分布联系起来。通过专门的校准测量，结果的保真度远远超出了最先进的水平，并放弃了传统的数据分析，通过快速，高度复用的模拟和机器学习辅助推理技术，支持一种新颖的前向建模方法。