Accurate and precise statistical methods for weak gravitational lensing

弱引力透镜的精确统计方法

• 批准号: 2471324
• 金额: --
• 依托单位: University of Edinburgh
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2471324
• 关键词: Accurate; precise; statistical; methods; weak

Gravitational lensing - the deflection of light from distant luminous sources by intervening matter - is a powerful technique for understanding our Universe. Coherent distortions in the shapes of galaxies can be used to infer the properties of the intervening dark matter, in particular its spatial distribution (i.e. how clumped or how smooth it is) and its evolution throughout cosmic history. Lensing is sensitive to the geometry of space-time and hence to the constituent components of the Universe. The dominant component is the so-called "dark energy", a poorly-understood source of energy-density which appears to mimic a cosmological constant term in the Einstein field equations. Gaining an understanding into the properties of dark energy is fundamental to our understanding of physics and is one of the main science drivers for upcoming cosmology surveys such as the Euclid space telescope. Having accurate and precise techniques for measuring the power spectrum of fluctuations in the lensing strength over the sky will be crucial for measuring dark energy properties with Euclid. The student will develop statistical methods inspired by analyses of the cosmic microwave background and apply them to realistic synthetic maps of cosmic shear. Edinburgh leads the weak lensing analysis of Euclid and hosts the UK Science Ground Segment Science Data Centre. There will be the opportunity to work within the Euclid weak lensing team, giving the student access to a state-of-the-art cosmology survey. There will also be opportunities to apply the methods to current data.

引力透镜--来自遥远光源的光被介入物质偏转--是理解我们宇宙的一种强大技术。星系形状的相干扭曲可以用来推断干预暗物质的性质，特别是它的空间分布（即它是如何聚集或如何平滑）及其在宇宙历史中的演化。透镜效应对时空的几何形状很敏感，因此对宇宙的组成成分也很敏感。占主导地位的成分是所谓的“暗能量”，这是一种对能量密度知之甚少的来源，它似乎模仿了爱因斯坦场方程中的宇宙学常数项。了解暗能量的性质是我们理解物理学的基础，也是即将到来的宇宙学调查（如欧几里得太空望远镜）的主要科学驱动力之一。拥有精确的技术来测量天空中透镜强度波动的功率谱，对于用欧几里得测量暗能量特性至关重要。学生将开发由宇宙微波背景辐射分析启发的统计方法，并将其应用于宇宙剪切的真实合成图。爱丁堡领导了欧几里得的弱透镜分析，并主持了英国科学地面部分科学数据中心。将有机会在欧几里得弱透镜团队工作，让学生获得最先进的宇宙学调查。还将有机会将这些方法应用于当前数据。