Unveiling the Structure of the Universe

这是一个雄心勃勃的提议，旨在促进我们对在我们宇宙中观察到的结构的理解，确保在STFC路线图中科学挑战的核心领域--非高斯宇宙和膨胀理论--的世界领先研究的发展：根据标准的膨胀范式，所观测到的星系和其他大型结构源于早期宇宙中的量子涨落。我们将通过对宇宙微波背景的普朗克卫星数据的详细统计观测来对抗来自膨胀模型的这些预测。在补充性研究中，超越简单的膨胀模型，我们将利用最近的理论进步，对我们宇宙中星系的分布做出更准确的预测。宇宙作为基础物理实验室：我们将探索天文观测如何提供关于基础物理的新信息。特别是，我们将调查是否有天文学证据证明一些基本物理常数是恒定的，以及是否可以对爱因斯坦的广义相对论进行重大修改。黑洞和引力物理学：引力波是时空中的涟漪，在黑洞或中子星合并或恒星超新星爆炸时形成。它们以光速在宇宙中传播，并将使我们能够以一种全新的方式看待宇宙，先进的探测器预计将在几年内上线。我们将用数值和解析的方法研究黑洞的稳定性及其引力波信号的形状，以便与未来的观测结果相比较。太阳系外行星系统的长期演化：我们研究太阳系外行星系统通过与中央恒星的潮汐相互作用的长期演化，这会影响自旋和轨道运动，并可能导致行星膨胀、向内迁移，甚至被摧毁。我们还研究了行星与原行星盘之间的长期引力相互作用，这种相互作用可以激发椭圆运动，在某些情况下还会摧毁行星。吸积盘的磁流体动力学：年轻恒星和黑洞周围的气态盘在宇宙中无处不在，驱动着宇宙中一些最迷人和最重要的过程。其中包括：行星形成、强大的喷流和外流、盘曲，以及以新生恒星系统和矮新星为特征的能量大爆发。连接这些不同现象的主线是气体中的湍流和磁场，我们通过大规模的数值模拟来研究这一点。太阳和恒星磁性中的尺度相互作用：太阳就像一台巨大的机器，其大尺度磁性特征相当规则和连贯地变化，正如众所周知的太阳黑子周期所表明的那样。然而，太阳中的运动是非常无序的。我们将研究太阳磁场的理论模型，该模型将显示这些无序流动如何结合在一起，产生观察到的周期。我们还将使用新的图像处理方法来了解更多关于太阳表面附近小尺度运动的细节。活跃太阳的光谱诊断和天体物理学：对太阳大气中过程的更深入了解将有助于我们描述加热日冕(超过100万度)并引发太阳耀斑和喷发，导致空间天气事件的能量释放。最近的太阳空间观测(SOHO、Hinode、SDO)提供了令人惊叹的图像(见www.suntrek.org)。然而，分析这些数据需要对EUV中的排放有详细的了解。这些信息由我们的团队提供，并通过一个名为基安蒂红酒的数据库公开，该数据库现在被广泛用于太阳物理和天体物理。

This is an ambitious proposal to advance our understanding of the structures observed in our Universe, ensuring the development of world-leading research in areas central to the Science Challenges in the STFC roadmap:The Non-Gaussian Universe and Inflationary Theory: According to the standard inflationary paradigm, the observed galaxies and other large-scale structure originated from quantum fluctuations in the early universe. We will confront these predictions from inflationary models with detailed statistical observations of the Planck satellite data of the cosmic microwave background. In complementary studies, moving beyond simple inflation models, we will exploit recent theoretical advances to make more precise predictions for the distribution of galaxies in our Universe.The Universe as a Fundamental Physics Laboratory: We will explore how astronomical observations can provide new information about fundamental physics. In particular, we will investigate whether there is astronomical evidence for the constancy of some fundamental constants of physics and whether there can be significant modifications to Einstein's theory of general relativity. These modifications may shed new light on why the expansion of the universe began accelerating a few billion years ago.Black Holes and Gravitational Physics: Gravitational waves are ripples in spacetime which form when black holes or neutron stars merge or in the supernova explosion of stars. They propagate across the universe at the speed of light and will enable us to view the universe in a qualitatively new way with advanced detectors expected to go online in a couple of years. We will study numerically and analytically the stability of black holes and the shape of their gravitational wave signals for comparison with future observations.Long-term Evolution of Extrasolar Planetary Systems: We study the long-term evolution of extrasolar planetary systems through their tidal interactions with the central star, which affect the spin and orbital motion and can cause planets to swell, migrate inwards and even be destroyed. We also study the long-term gravitational interactions of planets with the protoplanetary disc, which can excite elliptical motion and in some cases destroy planets.Magnetohydrodynamics of Accretion Discs: Gaseous discs around young stars and black holes are ubiquitous in the Universe and drive some of its most fascinating and important processes. Of these this project addresses: planet formation, powerful jets and outflows, disc warps, and the great outbursts of energy that characterise nascent stellar systems and dwarf novae. The thread linking these diverse phenomena is turbulence and magnetic fields in the gas, which we study through large-scale numerical simulations.Scale interactions in Solar and Stellar Magnetism: The Sun is like a giant machine, and its large scale magnetic features change fairly regularly and coherently, as shown by the well-known sunspot cycle. However motion in the Sun is very disordered. We shall investigate a theoretical model of the Sun's magnetic field that will show how these disordered flows can combine to produce the observed cycles. We shall also use novel image processing methods to learn more about the details of the small scale motions near the surface of the Sun.Spectroscopic Diagnostics for the Active Sun and Astrophysics: A deeper understanding of processes in the solar atmosphere will help us describe the energy release which heats the corona (to over a million degrees) and initiates solar flares and eruptions, leading to space weather events. Recent solar space observations (SoHO, Hinode, SDO) provide stunning images (see www.suntrek.org). However, the analysis of this data requires detailed knowledge of emission in the EUV. This information is provided by our group and made publicly available via a database called CHIANTI, which is now universally used in solar physics, and also astrophysics.