Astrophysics at the University of Birmingham - Consolidated grant 2022-2025

宇宙看起来非常不同，这取决于我们如何观察它。使用广泛的宇宙信使，全频谱的“电磁辐射”-从无线电波到红外辐射和光，到X射线和伽马射线-以及仅在几年前被称为引力波的空间和时间涟漪揭示了宇宙不是一个安静的地方。它的特点是暴力和戏剧性的现象，在短时间内产生巨大能量的强大爆炸。我们现在可以非常详细地研究许多这些灾难性事件，这要归功于大量一流的天文台，其中一些将在未来几年内上线。我们可能会再次感到非常惊讶，并发现新的现象。我们的节目从许多不同的角度看一些最令人兴奋的瞬态现象，并以黑洞和极端（“紧凑”）物体为中心。我们的目标是研究黑洞如何吞噬和撕碎星系中心的恒星。我们将利用光在宇宙尺度上的弯曲效应，通过大质量透镜-星系群和星系团-观察其中一些灾难性事件的多个图像，获得关于其引擎以及宇宙如何整体演化的新见解。我们还将第一次尝试“听到”宇宙的低语，即数十亿个太阳质量的黑洞在星系中心分裂并辐射引力波。我们相信我们现在可以用强大的银河系尺度的“仪器”来探测这种辐射，这些仪器是由被称为“太阳钟”的无线电灯塔提供给我们的超稳定时钟。如果这种情况发生，我们将打开一个新的宇宙观测窗口。黑洞也是非常简单的物体。它们是一种基本的引力粒子，测试它们的性质至关重要。利用我们现在经常用引力波激光干涉仪观测到的许多双黑洞，我们将以前所未有的精度检验围绕这些物体的最著名的预言之一：霍金的视界面积定理。我们上面描述的大多数或所有宇宙爆炸都发生在星系中，天文学家已经详细研究了几十年。然而，星系如何形成和演化为宇宙中被称为“宇宙网”的缠结结构的一部分仍然被神秘所包围。使用世界上一些最好的望远镜进行的新的强大调查将使我们能够测试现有的理论模型，我们将获得关于宇宙时间内星系演化的新见解，以及在这些环境中发生的无数相互关联的物理过程。

The Universe looks very different depending on how we observe it. The use of a broad range of cosmic messengers, the full spectrum of "electromagnetic radiation" - ranging from radio waves through infrared radiation and light, to X-rays and gamma rays - and, as of only a few years ago also ripples in space and time known as gravitational waves reveal that the Universe is not a quiet place. It is characterised by violent and dramatic phenomena, powerful explosions that produce astonishingly large mount of energy over short periods of time. We can now study many of these catastrophic events in great detail thanks to a large range of superb observatories, some of which coming on-line in the next couple of years. We may be very surprised yet again, and discover new phenomena.Our programme looks at some of the most exciting transient phenomena from many different angles and has black holes and extreme ("compact") objects at its centre. We aim to study how black holes devour and shred stars at the centre of galaxies. We will use the effect of bending of light over cosmic scales to observe through massive lenses - groups and clusters of galaxies - multiple images of some of these catastrophic events, gain new insights about their engines and how the Universe evolves as a whole. We will also try to "hear" for the very first time the cosmic whisper of the population of billion solar mass black holes paring up at the centre of galaxies and radiating gravitational waves. We believe we can detect this radiation now with powerful galactic scale "instruments", the ultra-stable clocks provided to us by radio lighthouses known as pulsars. If this happens, we would open a new observational window on the Universe.Black holes are also spectacularly simple objects. They are a sort of fundamental particle of gravity and testing their properties is of paramount importance. Using the many binary black holes that we now routinely observe with gravitational-wave laser interferometers we will test to unprecedented accuracy one of the most famous predictions surrounding these objects: Hawking's horizon area theorem.Most or all of the cosmic explosions that we have described above take place in galaxies, which astronomers have studied in great detail for many decades. However, how galaxies form and evolve as part of the tangled structures in the Universe known as "the cosmic web" is still surrounded by mystery. New powerful surveys using some of the best telescopes in the world will allow us to put existing theoretical models under test, and we will gain new insights about galaxy evolution over cosmic time and the myriad of interlinked physical processes that take place in these environments.