数值相对论与引力波天文学  

Numerical relativity and gravitational wave astronomy

作　　者：曹周键[1] 都志辉[2] CAO ZhouJian DU ZhiHui(Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190, China Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China)

机构地区：[1]中国科学院数学与系统科学研究院,北京100190 [2]清华大学计算机科学与技术系,北京100084

出　　处：《中国科学：物理学、力学、天文学》2017年第1期55-72,共18页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金资助项目(编号:11375260)

摘　　要：引力波直接探测已经被LIGO成功实现.在这个重大实验发现中,理论模型的重要作用得到充分体现.有效单体数值相对论模型不仅提升了既定硬件的灵敏度,把实验结果的置信度从4.6σ加强到5.1σ,而且还辨认出该引力波源是并合双黑洞.以这次实验结果所给出的双星并合事件率推断,地面引力波探测器接下来还会给出更多的引力波事件.这些引力波实验数据可以被用来进行天文学和基本物理学的研究.随着数据的积累和新脉冲星的加入,脉冲星计时计划的引力波探测精度也越来越高.空间引力波探测计划包括eLISA、太极和天琴等也在积极准备中.可以预期,引力波天文学将逐渐形成.在引力波天文学中,从信号读取到参数反演都离不开理论模型.不做任何解析近似的数值相对论是现实引力波源建模的通用工具.爱因斯坦方程的复杂数学结构和所需的庞大程序构架是数值相对论的两大困难.结合引力波天文学,本文对数值相对论的关键困难、发展历程、研究现状和在引力天文学中的应用等给出比较系统的描述.The first direct detection of gravitational wave has been realized by LIGO 100 years after Einstein＇s theoretical prediction. It opens a new window for human to observe our Universe and initiates the age of Gravitational Wave Astronomy. The data analysis of gravitational wave detection is a typically signal extraction problem and the matched filtering technique has shown to be an optimal method in extracting weak signal buried in strong Gaussian noises. Matched filtering requires the accurate gravitational waveforms. It is also essential for the parameter estimation of the gravitational wave source, with which the GW150914 was recognized as a binary of 29 and 36 solar masses black holes merging about 1.3 billion light years away. Nowadays, other laser interferometric gravitational wave detectors such as Virgo, KAGRA and the third LIGO in the India, IndiGO, are under construction. The space-borne detection projects including eLISA, Taiji and TianQin are also in progress. The pulsar timing approach with FAST, SKA and other radio telescope arrays to detect gravitational wave are also in the rapid development. It is foreseeable the gravitational wave astronomy in the wide frequency band from 10-~~ to 1000 Hz will be realized in the near future. As such, the matched filtering plays an important role, and correspondingly the theoretical research of gravitational wave source models becomes urgent and important. For astrophysical realistic objects without symmetries in general, the analytical treatment of Einstein equation becomes nearly intractable. The numerical relativity then becomes an essential method and tool for solving the Einstein equation. We briefly introduce the state of art research of numerical relativity in the viewpoint of gravitational wave astronomy.

关 键 词：数值相对论 引力波天文学 爱因斯坦方程 匹配滤波方法 

分 类 号：O412.1[理学—理论物理]