Sources for gravitational wave astronomy

随着第一代高灵敏度引力波探测器以设计灵敏度工作，对于广义相对论和天体物理学来说，这是一个令人兴奋的时代。随着先进探测器的升级计划，以及空间探测器Lisa将于未来十年发射，我们预计很快就能利用引力波数据来了解更多关于宇宙的信息。鉴于引力波天文学有可能探测其他黑暗或隐藏的过程，它有望极大地改变我们对黑洞和中子星的理解。收集到的信息将是对电磁观测信息的补充。然而，我们需要改进我们目前的预测来源模型。不仅需要更好的模型来探测引力波，而且还需要尽可能多的物理探测。这项研究建议建立在南安普顿广义相对论小组在黑洞、中子星和引力波天体物理学方面的专业知识的基础上，旨在加深对黑洞和中子星如何发出引力波的理解，以及如何利用这些信号来提供有关相关物理的信息。拟议方案具有高度相互关联的性质，有四个不同的主题，需要类似的方法(例如一般相对论微扰理论或数值模拟)和物理输入(例如超流、磁场或引力辐射反应)。总体目标是从涉及致密天体的一系列天体物理场景中开发出显著改进的引力波模型。中子星是独特的天体物理实验室，其建模需要许多鲜为人知的物理学。为了研究它们的性质，人们必须将超核物理与磁流体力学结合起来，描述超流体和超导体，潜在的奇异物质相，如去受限的夸克-胶子等离子体，当然还有广义相对论。由于它们可以以各种方式辐射引力波，因此更好地了解中子星动力学是这项提议的关键目标之一。为此，我们将开展三个平行项目，重点是中子星振荡、相关的天体物理情景和中子星动力学的完全非线性模拟。这项拟议的工作不仅与引力波物理有关，还将为与电磁观测相关的问题提供有用的见解。我们的目标是建立准确的磁星脉动模型，可以根据最近观测到的与磁星巨型耀斑相关的振荡来进行测试。我们对旋转效应的研究应该有助于揭示脉冲星的毛刺，而非线性模拟将有助于改进我们的中子星合并和原中子星演化模型。不断上升的双星本质上是宇宙中最强的引力波来源。特别是，LISA在探测致密物体进入银河系中心大质量黑洞的辐射灵感方面有着令人兴奋的前景。来自这类事件的引力波形是对大质量黑洞附近强引力的极其有效的探测，并有望在其最极端的区域内对引力理论进行准确测试。为了实现这一前景，我们需要从理论上很好地理解相对论辐射反应效应。最近在引力自力问题上取得的进展为这一领域的工作提供了巨大动力。在这个项目中，我们将继续探索这些令人着迷的来源的科学。

With the first generation of highly sensitive gravitational wave detectors operating at design sensitivity, this is an exciting time for general relativity and astrophysics. With upgrades to advanced detectors planned, and the space based detector LISA due for launch, in the next decade, we expect to soon be able to use gravitational wave data to learn more about the Universe. Given its potential for probing otherwise dark or hidden processes, gravitational wave astronomy promises to change our understanding of, in particular, black holes and neutron stars significantly. The information gleaned will be complementary to that from electromagnetic observations. However, we need to improve our current models of the predicted sources. Better models are needed not only to detect the gravitational waves in the first place, but also to probe as much physics as possible. This research proposal builds on the Southampton General Relativity Group's expertise in black hole, neutron star and gravitational wave astrophysics, and is aimed at developing a deeper understanding of how gravitational waves are emitted by black holes and neutron stars, and how the signals can be used to provide information about the involved physics. The proposed programme is of a highly interconnected nature with four different themes requiring similar methodology (e.g. general relativistic perturbation theory or numerical simulations) and physics input (e.g. superfluidity, magnetic fields or gravitational radiation reaction). The overall aim is to develop significantly improved models for gravitational waves from a range of astrophysical scenarios involving compact objects. Neutron stars are unique astrophysical laboratories, the modelling of which requires much poorly known physics. In order to investigate their properties, one must combine supranuclear physics with magnetohydrodynamics, a description of superfluids and superconductors, potentially exotic phases of matter like a deconfined quark-gluon plasma and, of course, general relativity. Since they can radiate gravitational waves in a variety of ways, achieving a better understanding of neutron star dynamics is one of the key aims of this proposal. To do this we will carry out three parallel projects, focused on neutron star oscillations, relevant astrophysical scenarios and fully nonlinear simulations of neutron star dynamics. The proposed work is not only relevant for gravitational wave physics, it will also provide useful insights into problems relevant for electromagnetic observations. We aim to contruct accurate models of magnetic star pulsations that can be tested against recent observations of oscillations associated with magnetar giant flares. Our studies of rotational effects should shed light on the pulsar glitches, while the nonlinear simulations will help improve our models of neutron star mergers and proto-neutron star evolution. Inspiralling binaries are intrinsically the strongest sources of gravitational waves in the Universe. In particular, there are exciting prospects for LISA to detect the radiative inspiral of compact objects into massive black holes in galactic centres. Gravitational waveforms from such events are extremely efficient probes of the strong gravity near the massive black hole, and promise to allow accurate tests of gravitational theory in its most extreme domain. In order to realise this promise we need a good theoretical understanding of relativistic radiation-reaction effects. Recent progress on the problem of the gravitational self-force provides significant momentum for work in this area. In this project we will continue to explore the science of these fascinating sources.