Cosmic Structures: From Cosmology to Interstellar Medium

宇宙结构：从宇宙学到星际介质

• 批准号: 249808-2012
• 负责人: Pogosyan, Dmitri
• 金额: $ 1.46万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=547414
• 关键词: Cosmic; Structures; Cosmology; Interstellar; Medium

Cosmologists are now confident in the overall picture of structure formation in our Universe. The complexity of our Universe came from tiny quantum fluctuations of matter at an early era when the Universe was rapidly inflating. Inhomogeneities later grew under the force of gravity into stars, galaxies and, at large scales, the galactic Web, leaving an imprint on the Cosmic Microwave Background (CMB) along the way. But fundamental questions have also been raised: How can we peek into details of that early inflationary stage before the Big Bang? What are the 'dark matter' and 'dark energy' that successful models have to assume to dominate in the Universe? How did the filamentary Cosmic Web of galaxies observed in 3D galactic catalogues come into being and is it organized? Much of what we know about the Universe, we learned from statistical analysis of the large scale distribution of matter and CMB sky-maps treated as random field. Geometrical analysis of such fields that I propose to pursue has the potential to answer these new central questions. The key is to look for deviations in geometrical statistics from the normal, so-called "Gaussian", behaviour. I have developed advanced theoretical description of such non-Gaussianity. Applied to CMB, it may tell us whether inflationary models can be distinguished between, or even disproved. Applied to present day evolution of the structure, it may help us to determine what the elusive "dark energy" is.

宇宙学家现在对宇宙结构形成的整体图景充满信心。我们宇宙的复杂性来自于早期宇宙迅速膨胀时物质的微小量子波动。后来，在引力的作用下，非均质性逐渐形成了恒星、星系，在大尺度上形成了银河网，并在宇宙微波背景（CMB）上留下了印记。但也提出了一些基本问题：我们如何才能窥视到大爆炸之前早期膨胀阶段的细节？成功的模型必须假设在宇宙中占主导地位的“暗物质”和“暗能量”是什么？在三维星系目录中观测到的丝状宇宙网是如何形成的，它是有组织的吗？我们对宇宙的了解，大多来自于对物质大尺度分布的统计分析，以及被视为随机场的CMB天空图。我打算对这些领域进行的几何分析有可能回答这些新的中心问题。关键是在几何统计中寻找偏离正态的偏差，即所谓的“高斯”行为。我已经发展了这种非高斯性的高级理论描述。应用于CMB，它可以告诉我们是否可以区分暴胀模型，甚至是否定暴胀模型。应用于目前的结构演化，它可以帮助我们确定难以捉摸的“暗能量”是什么。