Strongly Gravitating Systems and Waves in General Relativity

本研究是对强引力系统的数值研究，特别强调它们在动力演化中产生的引力波的性质。它使用超级计算机进行完全的数值处理，以及与数值处理紧密结合的半解析方法，来研究高度非线性和动态的天体物理事件，如由中子星和/或黑洞组成的紧致双星系统的启发合并。三维黑洞时空的精确数值构建与分析是研究的重点之一。与传统的利用时间切片来避免黑洞时空固有的奇点的方法不同，孙教授的团队将开发一种完全3+1数值相对论的方法，该方法使用视视界作为动态演化的内部边界。这种视界边界条件方法有望对黑洞时空的数值研究产生重大影响。视界和事件视界是黑洞的重要特征。PI正在开发程序来确定它们的存在和位置，以及在数字构建的3+1维时空中分析它们属性的工具。这些例程将很快提供给数值相对论界，将对黑洞的研究产生影响。

This research is on the numerical study of strongly gravitating systems with special emphasis on the properties of the gravitational waves they generated in dynamical evolutions. This uses supercomputers for fully numerical treatments, and semi-analytical methods closely coupled to the numerical treatments, to study highly non-linear and dynamical astrophysical events, like the inspiral coalescence of compact binary systems consisting of neutron stars and/or black holes. One of the focuses of the research is on the accurate numerical constructions and analyses of 3D black hole spacetimes. Instead of the traditional approach of using time slicings to avoid the singularities inherent in black hole spacetimes, Prof. Suen's group will develop an approach in full 3+1 numerical relativity which uses the apparent horizons as inner boundaries in dynamical evolutions. This apparent horizon boundary condition approach is expected to have major impact on the numerical study of black hole spacetimes. Apparent horizons and event horizons are important characteristic of black holes. The PI is developing routines to determine their existence and locations, as well as tools for analyzing their properties, in a numerically constructed 3+1 dimensional spacetime. These routines, to be available to the numerical relativity community soon, will have impact on the study of black holes.