Collaborative Research: Accelerating the Pace of Discovery in Numerical Relativity by Improving Computational Efficiency and Scalability

引力波天文学的曙光才刚刚开始，LIGO和处女座引力波探测器已经有了一些令人震惊的发现。未来对这些探测器的升级，以及新探测器的出现，如KAGRA，将显著扩大引力波科学的范围。随着引力波探测器在未来十年灵敏度的提高，这些事件的数值解的精度必须在相同的时间框架内相应增加至少一个数量级。这是一项重大的计算挑战，必须加以应对，才能充分发挥新探测器的科学潜力。这个项目将使用Dendro-GR创建的计算机模拟来研究双星中子星和黑洞的合并，Dendro-GR是一种在最大的超级计算机上非常高效地运行的新计算机代码。广义相对论的检验也将通过检验不同的引力模型来进行。将探索求解微分方程组的新算法，以提高二进制合并的长时间模拟的效率。为这个项目所做的工作将促进科学的进步，并为包括计算机科学、数学和物理在内的多个STEM领域的本科生和研究生培养做出贡献。最后，Dendro-GR是一个开源项目。该项目将在当前计算能力的前沿研究合并二进制紧凑对象的动力学。对各种各样可能的合并进行建模的能力将相应地增加引力波科学家发现和理解这些高能事件的能力，并寻找可能存在于我们当前引力模型之外的新物理。该项目将针对以下目标：(1)将扩展DREDRO-GR计算框架，以计算用于波形星表的具有足够精度的双中子星激发的引力波形。(2)研究具有大质量比的双星黑洞激发星，以扩大电流波表的范围。(3)合并黑洞双星的引力波形将在另一种引力理论中进行计算，以探索与广义相对论预测的可能偏差，并在我们目前的引力模型之外寻找新的物理。(4)将通过减少求解时间来研究提高数值相对论中的精度的计算挑战。这个复杂的问题需要一种广泛的方法，使用GPU，创新的有限差分，改进的空间离散，并使时间离散更并行。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The dawn of gravitational wave astronomy is just beginning, and the LIGO and Virgo gravitational wave detectors have already made some stunning discoveries. Future upgrades to these detectors, as well as the advent of new detectors, such as Kagra, will significantly expand the range of gravitational wave science. As the sensitivity of gravitational wave detectors improves over the next decade, the accuracy of numerical solutions of these events must correspondingly increase by at least an order of magnitude in the same time frame. This is a significant computational challenge that must be met to enable the full scientific potential of the new detectors. This project will study mergers of binary neutron stars and black holes using computer simulations created by Dendro-GR, a new computer code that runs very efficiently on the largest supercomputers. Tests of general relativity will also be performed by examining alternative models of gravity. New algorithms for solving differential equations will be explored to improve the efficiency of long simulations of binary mergers. Work done for this project will promote the progress of science and contribute to undergraduate and graduate training in multiple STEM fields including computer science, mathematics, and physics. Finally, Dendro-GR is an open source project.This project will study the dynamics of merging binary compact objects at the frontier of current computational capabilities. The ability to model a wide variety of possible mergers will correspondingly increase the ability of gravitational wave scientists to find and understand these high-energy events, and to search for possible new physics that lies beyond our current gravitational models. This project will be directed at the following goals: (1) The Dendro-GR computational framework will be expanded to calculate gravitational waveforms for binary neutron star inspirals of sufficient accuracy to be used in waveform catalogs. (2) Binary black hole inspirals with large mass ratios will be studied to expand the range of current waveform catalogs. (3) Gravitational waveforms for merging black hole binaries will be calculated within alternative gravitational theories to probe possible deviations from the predictions of general relativity and to search for new physics beyond our current model for gravity. (4) The computational challenge of improving accuracy in numerical relativity will be studied by focusing on reducing the time-to-solution. This complicated problem requires a broad approach that uses GPUs, innovative finite differencing, improved spatial discretizations, and exposing the temporal discretization to more parallelism.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.