CAREER: Exploring the Warped Spacetimes of Astrophysical Black Holes

目前对早期宇宙中超大质量黑洞的观测对我们对这些独特天体的形成和成长的理解提出了严重的问题。Dimitrios Psaltis博士（亚利桑那大学）将确定超大质量黑洞是否可以在早期宇宙中仅通过吸积来生长。这将通过使用光谱、3D、磁流体动力学算法模拟黑洞的吸积流来实现，该算法最近由Psaltis博士和他的团队开发，并将通过结合辐射过程的详细处理进一步增强。这项研究的结果将是第一次对超大质量黑洞的极限质量吸积率进行从头计算。该项目还将评估利用吸积黑洞进行重力测试的可行性。此外，它将利用参数理论框架，确定天体物理学黑洞是否可以用广义相对论的克尔度规来描述。该研究项目的一个组成部分将是开发用于在任意弯曲时空中可视化粒子和光子轨道的模块。这些模块将成为教育学生几何理论各个方面的宝贵工具。在几名本科生的协助下，他将开发一个独立的、基于网络的、用于相对论概念教学的可视化工具。两名研究生和几名本科生将在研究项目中接受相对论、计算天体物理学和输运方法的各个方面的教育，这两个方面对天体物理学以外的许多物理学科的研究都很重要。

Current observations of supermassive black holes in the early Universe pose serious questions on our understanding of the formation and growth of these unique astrophysical objects. Dr. Dimitrios Psaltis (University of Arizona) will determine whether supermassive black holes can grow in the early Universe solely by accretion. This will be achieved by simulating accretion flows onto black holes using the spectral, 3D, magnetohydrodynamic algorithm recently developed by Dr. Psaltis and his group, which will be further enhanced by incorporating a detailed treatment of radiative processes. The result of this investigation will be the first ab initio calculation of the limiting rate of mass accretion by a supermassive black hole. This project will also assess the viability of performing tests of gravity using accreting black holes. Moreover, it will establish, using a parametric theoretical framework, whether the astrophysical black holes are described by the Kerr metric of General Relativity.An integral part of this research project will be the development of modules for the visualization of particle and photon orbits in arbitrary curved spacetimes. These modules will become valuable tools in educating students in the various geometric aspects of the theory. Dr. Psaltis, assisted by several undergraduate students, will develop a self contained, web-based, visual tool for the teaching of relativistic concepts. Two graduate students and several undergraduate students will be educated during the research program in various aspects of relativity, computational astrophysics, and transport methods, both of which are important for a number of disciplines of physics research other than astrophysics.