Dynamical and Strong-Field Gravitational-Wave Phenomenology

美国国家科学基金会的激光干涉引力波天文台（LIGO）和合作设施观测了近100个黑洞和中子星合并产生的引力波。这些非凡的测量开启了引力波天体物理学的一个新领域，使人们能够以新的方式研究引力。为了解释这些观测结果并了解爱因斯坦的广义相对论，描述这些波的基本引力理论，必须对两个黑洞合并期间发射的引力波进行精确计算。该奖项支持结合第一原理计算，数据分析程序以及黑洞的分析和数值建模的研究工作，这些研究将用于从引力波观测中提取见解。许多计算将由研究生进行，他们将接受在物理研究和其他定量领域有用的技术培训。该奖项的最后一个组成部分将是关于黑洞和引力波的一般主题的短文，以帮助将这些主题介绍给更广泛的小说和非小说读者。这些作品将在PI的研究网站上免费阅读。更具体地说，这个项目的目标是在几个方向上取得引力物理学的进展。(i)PI和学生将计算持续的引力波信号从双黑洞使用一致性关系确定从最近确定的守恒定律在渐近平坦的时空;这些信号的检测前景将进行评估。(ii)他们将对被称为引力波记忆的持久可观测波进行建模，这种波最有可能从双星合并中被检测到。通过他们改进的模型，他们将重新评估记忆效应在观测到的黑洞合并中的重要性。(iii)它们将改善对黑洞双星发出的引力波的计算，这些黑洞双星具有大的质量比，被密集分布的暗物质包围。暗物质及其与双星的相互作用将被更准确地建模，这将有助于在数据分析和参数估计预测中产生更小的偏差。(iv)他们将开发黑洞合并的引力波形，修改爱因斯坦的理论，涵盖合并过程的所有阶段。这些近似的波形可以帮助揭示一个更简单的图片合并的更复杂的现象，并可以用于广义相对论的引力波测试。这个奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

The NSF's Laser Interferometer Gravitational-Wave Observatory (LIGO) and collaborating facilities observed gravitational waves from nearly one hundred merging black holes and neutron stars. These remarkable measurements opened a new field of gravitational-wave astrophysics, which is allowing gravity to be studied in new ways. To interpret the results of these observations and learn about Einstein's general relativity, the underlying theory of gravity that describes these waves, precise calculations must be carried out of the gravitational waves that are emitted during the merger of two black holes. This award supports a research effort that combines first-principles calculations, data-analysis procedures, and analytical and numerical modeling of black holes, which will be used to extract insights from gravitational-wave observations. Many of the calculations will be carried out by graduate students, who will be trained in techniques that are useful in physics research and other quantitative areas. A final component of the award will be short essays about the general themes of black holes and gravitational waves, to help introduce these subjects to a wider audience of fiction and non-fiction readers. The writings will be free to read on the research website of the PI. More specifically, the goals of this project will be to make advances in gravitational physics in several directions. (i) The PI and students will compute persistent gravitational-wave signals from binary black holes using consistency relations determined from recently identified conservation laws in asymptotically flat spacetimes; the detection prospects of these signals will be assessed. (ii) They will model the waves of the persistent observable called the gravitational-wave memory, which has the best chance of being detected from binary mergers. With their improved model, they will reassess the significance of the memory effect in the observed black-hole mergers. (iii) They will improve the computation of gravitational waves emitted from black-hole binaries with large mass ratios that are surrounded by dense distributions of dark matter. The dark matter and its interaction with the binary will be modeled more accurately, which will help produce smaller biases in the data analysis and parameter estimation forecasts. (iv) They will develop gravitational waveforms for mergers of black holes in modifications of Einstein’s theory that cover all the stages of the merger process. These approximate waveforms can help reveal a simpler picture of the more complicated phenomenology of the merger and could be used in gravitational-wave tests of general relativity.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.