Research in Black-Hole Physics and Relativistic Astrophysics

该奖项支持相对论和相对论天体物理学的研究。这项研究的很大一部分是通过超级计算机模拟来解决爱因斯坦方程的数值问题。其中一个重点是跟踪双黑洞系统的合并和合并，并计算这些过程发出的引力波形。这些过程是目前正在部署的引力波探测器（如LIGO）的主要目标，并且迫切需要可靠的波形。研究人员将使用一种计算技术，即伪光谱搭配，它比其他技术以更小的计算成本提供更高的精度。其他应用将包括分析近似的基准测试，如后牛顿和有效一体技术；高自旋和高质量比等复杂参数空间的计算；以及对数值时空的分析探索，以提高我们对强场重力的理解。研究的第二个重点是研究包含一颗中子星和一个黑洞或两颗中子星的双星系统的聚结和合并。这些也是LIGO的主要科学目标。研究人员将在模拟中加入更真实的微物理描述，如核物质的状态方程、中微子效应和磁场。这项研究将对我们对基础物理学的理解产生广泛的影响。目前还没有在黑洞强场范围内对广义相对论进行真正的检验。对于像LIGO这样的实验来说，要用观测来对抗理论，人们必须能够计算出理论所预测的东西。LIGO可能观测到的黑洞是爱因斯坦理论预言的黑洞吗？这项研究将对天文学产生影响。包含中子星的致密双星的合并可能导致电磁和中微子信号的发射，从而开启了以多种方式同时观察此类事件的可能性，从而更好地了解此类事件。该项目进行的模拟将有助于确定要寻找什么信号，以及在检测到信号时如何解释这些信号。这项研究还将对计算科学的更广泛领域产生影响。在这里开发的计算技术可以用于解决许多其他领域的问题，包括流体动力学、气象学、地震学和天体物理学。在这些技术方面受过训练的年轻研究人员需求量很大。

This award supports research in relativity and relativistic astrophysics. A large component of the research is aimed at the numerical solution of Einstein's equations by supercomputer simulations. One focus is to track the coalescence and merger of binary black hole systems and to calculate the gravitational waveform emitted by such processes. These processes are primary targets for gravitational wave detectors now being deployed, like LIGO, and there is an urgent need for reliable waveforms. The investigators will use a computational technique, pseudospectral collocation, that delivers high accuracy with a much smaller computational cost than other techniques.Other applications will include benchmarking of analytical approximations, such as the post-Newtonian and Effective One Body techniques; computations in difficult regimes of parameter space such as high spins and mass ratios; and analytical explorations of the numerical spacetimes to improve our understanding of strong field gravity. A second focus of the research is to study the coalescence and merger of binary systems containing a neutron star and a black hole, or two neutron stars. These are also prime scientific targets for LIGO. The investigators will include ever more realistic descriptions of the microphysics in the simulations, such as the equation of state of nuclear matter, neutrino effects,and magnetic fields.This research will have a broad impact on our understanding of fundamental physics. There are currently no real tests of general relativity in the strong field regime of black holes. For experiments like LIGO to confront theory with observation, one must be able to calculate what the theory predicts. Are the black holes that LIGO may observe the black holes predicted by Einstein's theory? The research will have an impact on astronomy. Mergers of compact binaries containing neutron stars may lead to the emission of electromagnetic and neutrino signals, opening the possibility of concurrently observing such events in multiple ways leading to greater understanding of such events. Simulations carried out by this project will help determine what signals to look for and how to interpret them when they are detected. The research will also have an impact on the broader area of computational science. The computational techniques to be developed here can be used to solve problems in many other areas, including fluid dynamics, meteorology, seismology, and astrophysics. Young researchers trained in these techniques are in great demand.