ITR: MHD Simulations in Full General Relativity

根据该奖项，将开发用于研究涉及相对论重力、强电磁场和旋转的天体物理系统的数值工具。这些工具将包括在固定引力场中演化流体和电磁场的计算机代码，演化相对论引力场本身的代码，以及同时演化物质和电磁场的引力场的组合代码。还将开发用于验证积分准确性的工具。这些代码将在最新一代的超级计算机上进行优化，公开发布，并在科学界提供。在开发这些代码的过程中，计算科学家将接受本科生、研究生和博士后水平的培训。这些代码还将被开发人员应用于天体物理和引力物理研究的前沿问题。这项工作是由一些天体物理系统推动的，包括：吸积黑洞和中子星；合并双星中子星和黑洞；在核心塌缩的超新星中形成的快速旋转的中子星；以及塌缩的超大质量恒星。综上所述，这些天体是目前大部分天体物理研究的重点。它们可能是可探测到的引力波、强大的X射线发射和伽马射线爆发的来源。然而，到目前为止，他们还无法理解，因为流体、电磁场和引力场的基本物理是复杂的、非线性的和依赖于时间的。只有数值积分才能解开黑洞吸积的基本物理，测试产生伽马射线爆发的情景，并从聚合的致密双星产生更准确的引力波形预测。所需的数值方法尚不存在；它们将在本奖项下开发。

Under this award, numerical tools will be developed for thestudy of astrophysical systems involving relativisticgravity, strong electromagnetic fields, and rotation. Thesetools will include computer codes for evolving fluids andelectromagnetic fields in a fixed gravitational field, codesfor evolving the relativistic gravitational field itself,and a combined code that will evolve gravitational fieldswith both material and electromagnetic sources. Tools forverifying the accuracy of the integrations will also bedeveloped. The codes will be optimized for use on thelatest generation of supercomputers, publicly released, andmade available within the scientific community. In thecourse of developing these codes, computational scientistswill be trained at the undergraduate, graduate, andpostdoctoral levels. The codes will also be applied by thedevelopers to problems at the forefront of astrophysics andgravitation physics research.This work is motivated by a number of astrophysical systems,including: accreting black holes and neutron stars;coalescing binary neutron stars and black holes; rapidlyrotating neutron stars formed in core-collapse supernovae;and collapsing supermassive stars. Taken together, theseobjects are the focus of a large fraction of currentastrophysical research. They are the likely source ofdetectable gravitational waves, powerful X-ray emission, andgamma-ray bursts. So far, however, they have resistedunderstanding because the underlying physics of the fluid,the electromagnetic field, and the gravitational field iscomplicated, nonlinear, and time dependent. Only numericalintegrations can unlock the fundamental physics of blackhole accretion, test scenarios for the generation ofgamma-ray bursts, and generate more accurate predictions forgravitational waveforms from coalescing compact binaries.The required numerical methods do not yet exist; they willbe developed under this award.