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arXiv 0907.2760gr-qchep-th
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高维数值相关性:公式化和代码检验

Higher-dimensional numerical relativity: Formulation and code tests

Hirotaka Yoshino, Masaru Shibata

摘要:

我们推导出一个形式主义的数值相对论的高维时空和开发的数值代码模拟各种各样的五维(5D)时空的第一次。首先,Baumgarte-Shapiro-Shibata-Nakamura形式主义扩展到任意时空维度$D \ge 4$,然后,所谓的卡通方法,这是最初提出的一个强大的方法来模拟轴对称的4D时空,描述了5D时空的几种类型的对称性。用卡通方法实现了5D数值相对论程序,并通过演化一个5D史瓦西时空和一个由小振幅引力波包组成的5D时空进行了测试模拟。数值模拟稳定地进行了足够长的时间,在4D的情况下,所得到的数值结果与解析解吻合良好:数值解收敛在正确的顺序。我们还证实,长期准确的演化的5D史瓦西时空是可行的,使用所谓的穿刺方法。此外,我们还导出了任意维的Landau-Lifshitz赝张量,并证明了它为计算引力波的能流提供了一个强有力的工具。本文所发展的公式和方法为研究高维引力的非线性动力学提供了有力的工具。

英文摘要:

We derive a formalism of numerical relativity for higher-dimensional spacetimes and develop numerical codes for simulating a wide variety of five-dimensional (5D) spacetimes for the first time. First, the Baumgarte-Shapiro-Shibata-Nakamura formalism is extended for arbitrary spacetime dimensions $D \ge 4$, and then, the so-called cartoon method, which was originally proposed as a robust method for simulating axisymmetric 4D spacetimes, is described for 5D spacetimes of several types of symmetries. Implementing 5D numerical relativity codes with the cartoon methods, we perform test simulations by evolving a 5D Schwarzschild spacetime and a 5D spacetime composed of a gravitational-wave packet of small amplitude. The numerical simulations are stably performed for a sufficiently long time, as done in the 4D case, and the obtained numerical results agree well with the analytic solutions: The numerical solutions are shown to converge at the correct order. We also confirm that a longterm accurate evolution of the 5D Schwarzschild spacetime is feasible using the so-called puncture approach. In addition, we derive the Landau-Lifshitz pseudo tensor in arbitrary dimensions, and show that it gives a robust tool for computing the energy flux of gravitational waves. The formulations and methods developed in this paper provide a powerful tool for studying nonlinear dynamics of higher-dimensional gravity.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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