Numerical Relativity for Gravitational Wave Source Modeling

The first direct detection of gravitational wave has been realized by LIGO in 2015. It opens a brand new window to observe our universe and initiates the gravitational wave astronomy. The matched filtering technique is an optimal method to dig out the gravitational wave signal that is buried in the strong noise. The matched filtering technique is also essential to estimate the parameters of the gravitational wave source. Matched filtering requires a bank of accurate gravitational waveforms. Nowadays, two LIGO detectors and one Virgo are working. Other laser interferometric gravitational wave detectors such as KAGRA and the third LIGO in India, IndIGO, are developing. The space-borne detection projects including LISA, Taiji, and TianQin are also in progress. The pulsar timing approach with FAST, SKA, and other radio telescopes to detect gravitational wave is also in the rapid development. It is foreseeable the gravitational wave astronomy in the wide frequency band from 10−9 to 1000 Hz will be realized in the near future. Since the matched filtering plays an important role, the modeling of gravitational wave sources is urgent and important. For realistic objects without any symmetry, the analytical treatment of Einstein equation becomes nearly intractable. The numerical relativity is the most robust and reliable method and tool for solving the Einstein equation. We introduce the research of numerical relativity in the viewpoint of gravitational wave astronomy.