Cosmology and Astrophysics at Portsmouth

这项综合拨款是为了支持朴茨茅斯大学宇宙学和引力研究所（ICG）的宇宙学家和天体物理学家。ICG于2002年通过该大学的战略投资成立，现在拥有50名研究人员，使其成为英国最大的星系外天文学团体之一，例如在最近的REF2014中研究产出排名第八。在新的实验和理论进步的推动下，宇宙学和天体物理学正在经历一个发现的黄金时代。然而，在建立一个更完整的宇宙模型之前，我们仍然面临着三个根本性的挑战：1)构成宇宙96%的“暗物质”和“暗能量”的性质是什么？星系是如何形成和演化的？iii)宇宙结构的起源和统计性质是什么？这笔拨款将通过开创性的理论工作和利用新的天空调查来绘制数十亿遥远星系的地图，解决这些基本问题。星系是宇宙的“积木”，研究它们是如何形成的，我们将利用星系来提高我们对宇宙学（宇宙作为一个整体的属性）的理解。我们将利用当前和即将到来的星系调查，包括暗能量调查，SDSS-IV， SERVS和欧几里得来测量许多宇宙学探测器，如星系集群，超新星和弱引力透镜（由于引力导致的星系形状扭曲）。精确的宇宙学模型将被构建和分析，并用朴茨茅斯的SCIAMA超级计算机进行模拟。这些模型将与数据进行比较，以揭示宇宙的宇宙学特性。这些调查将通过测量星系的颜色和获取星系的详细光谱来研究星系是如何形成的。我们还将通过比较邻近宇宙中的星系来研究星系的演化，显示它们的现状，与遥远宇宙的星系相比，这为我们提供了一个了解过去的窗口。把我们所有的工作结合起来，我们将模拟和测量宇宙在其整个历史中的演变。我们将研究早期宇宙中的量子涨落如何被早期宇宙中的暴胀拉伸到天文尺度，并在今天宇宙中光和物质的分布中留下印记。我们还将探索爱因斯坦广义相对论的特征印记，以及暗能量在塑造我们宇宙结构演变中的作用。此外，我们的分析将揭示暗物质的特性，我们可以通过引力“看到”暗物质，但它不像正常物质那样相互作用。我们还将对整个宇宙时间内星系的特征有更全面的了解。这将告诉我们，关于暗物质的通常假设是否提供了对星系形成和演化的充分描述。ICG工作人员致力于向公众宣传，并在媒体和当地社区参与了一些引人注目的活动。例如，我们的工作人员访问了许多当地的学校，讨论他们的职业，他们的研究，并分享他们对天体物理学和宇宙学的热情，例如BBC观星直播在过去的几年里有数千名参与者

This consolidated grant is to support cosmologists and astrophysicists in the Institute of Cosmology and Gravitation (ICG) at the University of Portsmouth. The ICG was formed in 2002 through a strategic investment from the university, and now hosts 50 researchers making it one of the largest extragalactic astronomy groups in the UK e.g. ranked 8th in research outputs in the recent REF2014.Cosmology and astrophysics are experiencing a golden age of discovery driven by new experiments and theoretical advances. However, we still face three fundamental challenges before a more complete model of the Universe can be achieved: i) What are the properties of the "dark matter" and "dark energy" that make up 96% of the Universe? ii) How do galaxies form and evolve? iii) What is the origin, and statistical nature, of structures in the Universe? This grant will address these fundamental problems through pioneering theoretical work and the use of new surveys of the sky to map billions of distant galaxies. Galaxies are the "building blocks" of the Universe and as well as studying how they form, we will use the galaxies to improve our understanding of cosmology (the properties of the Universe as a whole). We will exploit current and forthcoming galaxy surveys including the Dark Energy Survey, SDSS-IV, SERVS and Euclid to measure numerous probes of cosmology such as the clustering of galaxies, supernovae and weak gravitational lensing (distortions of the galaxies' shape due to gravity). Precise cosmological models will be constructed and analysed, and simulated with Portsmouth's SCIAMA supercomputer. These models will be compared to data to reveal the cosmological properties of the Universe. The surveys will be used to study how galaxies form, by measuring their colours and taking detailed spectra of the galaxies. We will also study the evolution of galaxies by comparing the galaxies in the nearby Universe, showing their present state, with those of the distant Universe, which gives us a window into the past.Bringing together all our work, we will model and measure the evolution of the Universe throughout its entire history. We will study how quantum fluctuations in the very early universe may be stretched by inflation in the very early universe to astronomical scales, leaving their imprint in the distribution of light and matter in the universe today. We will also explore the characteristic imprint of Einstein's general relativity and the role of dark energy in shaping the evolution of structure in our Universe. Additionally, our analyses will shed light on the properties of dark matter, which we can "see" via gravity but which does not interact like normal matter. We will also obtain a fuller understanding of the characteristics of galaxies throughout cosmic time. This will tell us whether the usual assumptions about dark matter provide an adequate description of the formation and evolution of galaxies.ICG staff are committed to public outreach and have been engaged in a number of high-profile activities in the media and local community. For example, our staff have visited many local schools to discuss their careers, their research, and share their enthusiasm for astrophysics and cosmology, e.g. BBC Stargazing Live for the last few years with thousands of participants