Uncovering the dynamics of black holes and neutron stars for gravitational wave and multimessenger astronomy

随着LIGO/Virgo最近对合并的黑洞和中子星产生的引力波进行了令人惊叹的观测，我们进入了一个多使者天文学的新时代。所有迹象表明，随着引力波探测器的数量和灵敏度在未来几年的增加，将会有大量的观测，揭示出只有引力波才能看到的宇宙的新方面。然而，要最大限度地实现这些观测的回报，并将它们用作基础物理的新探索，将需要我们在这一体制下对引力的理论理解方面取得进展。*这项提议的核心部分是研究中子星合并--宇宙中密度最大的恒星的猛烈碰撞--最终目标是理解引力波信号和伴随的电磁瞬变，以帮助确定目标并解释当前和未来的观测结果。作为实现这一长期目标的一部分，我和我的团队将研究这些系统中仍然知之甚少的几个方面，包括中子星自转和轨道偏心率的影响，以及合并后残余物和吸积盘的动力学，并确定它们如何能够揭示最高密度核物质的行为，宇宙中最重元素的起源，以及其他问题。我和我的团队将研究相对论黑洞喷流的基本机制，这些喷流支配着各种大小的黑洞系统，从中子星合并产生的黑洞，到居住在星系中心的黑洞系统。我们将阐明旋转黑洞的几何形状和巨大的旋转能量储存库在为喷流提供动力方面的作用，无论是在静态情况下还是在动态情况下。这将涉及弥合对等离子体动力学的不同描述之间的分歧，以包括黑洞时空的影响，以及加速和加热等粒子效应。我和我的团队还将探索如何利用这一极端引力的新窗口来寻找新的基本物理，如暗物质的起源。我们将确定如何使用引力波观测通过超辐射来探测新粒子的存在，超辐射是一种导致黑洞以牺牲旋转能量为代价形成超轻玻色子云的过程。我们还将研究如何在某些暗物质模型中将中子星转化为黑洞，并了解观测信号。*这项研究将为学生提供参与一个快速增长的领域的机会，使他们能够流利地掌握包括天体物理、重力、粒子物理和计算物理在内的许多主题。他们将发展高等数学、软件开发和高性能计算方面的技能，这些技能在学术界和数据科学等技术领域都越来越需要。**

With the stunning observations of gravitational waves from merging black holes and neutron stars made recently by LIGO/Virgo, we have entered a new age of multimessenger astronomy. There is every indication that as the number and sensitivity of gravitational wave detectors increase in the coming years, that there will be a flood of observations, revealing new aspects of the universe visible only in gravitational waves. However, maximizing the return of these observations, and utilizing them as a new probe of fundamental physics will require advances in our theoretical understanding of gravity in this regime. ******A central part of this proposal is to study neutron star mergers--the violent collision of the densest stars in the Universe--with the ultimate goal of understanding the gravitational wave signal, and accompanying electromagnetic transients, in order to aid in targeting and interpreting current and future observations. As part of achieving this long-term goal, my team and I will study several aspects of these systems that remain poorly understood, including the effects of neutron star spin and orbital eccentricity, and the dynamics of the post-merger remnant and accretion disk, and determine how they can shed light on the behavior of nuclear matter at the highest densities, the origin of the heaviest elements in the universe, and other questions.******My team and I will study the underlying mechanisms of relativistic black hole jets that govern accreting black hole systems of all sizes, from those arising from neutron star mergers, to those residing at the centers of galaxies. We will elucidate the role of a spinning black hole's geometry, and large reservoir of rotational energy, in powering jets, both in stationary and dynamical scenarios. This will involve bridging the divide between different descriptions of the plasma dynamics to include the effects of both the black hole spacetime, as well as particle effects like acceleration and heating.******My team and I will also explore how this new window into extreme gravity can be used to look for new fundamental physics, such as the origin of dark matter. We will determine how gravitational wave observations can be used to probe the existence of new particles through superradiance, a process which causes black holes to form clouds of ultralight bosons at the expense of their rotational energy. We will also study how neutron stars could be converted into black holes in some models of dark matter, and understanding the observational signatures. ******This research will provide students with the chance to participate in a rapidly growing field, gaining fluency in a number of topics including astrophysics, gravity, particle physics, and computational physics. They will develop skills in advanced mathematics, software development, and high-performance computing that are increasingly in demand both in academia and areas of technology like data science.**