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RUI: Studies in Numerical Relativity

RUI：数值相对论研究

基本信息

批准号：
1707526
负责人：
Thomas Baumgarte
金额：
$ 22.59万
依托单位：
Bowdoin College
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-08-01 至 2021-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1707526&HistoricalAwards=false
关键词：
RUI Studies Numerical Relativity

项目摘要

Einstein's theory of general relativity describes all gravitational interactions in the universe, ranging from the force that pulls a falling apple to the Earth, to the expansion of the Universe itself. The equations of general relativity - called Einstein's equations - are quite complicated and can be solved exactly, i.e. with pencil and paper, only under very special and unrealistic circumstances. Modeling more realistic scenarios - for example in order to understand a gravitational wave signal, emitted by two merging black holes, and detected by the LIGO gravitational wave observatory - requires computer simulations. This group's ongoing research efforts aim at developing methods and approaches for such computer simulations. In recent years, the PI has developed new methods that are well suited for a new class of problems, and that may make current simulations significantly more efficient. In the next few years he plans to adopt these methods to study so-called "critical phenomena" that occur at the onset of back-hole formation, to examine properties of rapidly rotating neutron stars, and to collaborate with colleagues to make the above-mentioned new methods available in public community codes. Undergraduate students will participate in these activities, providing them with a "hands-on" research experience, and generating a research-enriched learning environment at Bowdoin College.The scientific goals of this research effort in numerical relativity include the development and implementation of numerical algorithms for the solution of Einstein's equations of general relativity, as well as their application in the numerical modeling of relativistic objects, in particular neutron stars and black holes. In the next funding period the PI plans to adopt methods for numerical relativity in spherical polar coordinates, previously developed with support from NSF grants, to study several problems in gravitational physics and relativistic astrophysics, in particular, to use this code to study critical collapse in the absence of spherical symmetry. Extending earlier results the PI plans to study the effects of angular momentum and aspherical deformations on critical phenomena in the gravitational collapse of perfect fluids, scalar fields, and vacuum spacetimes, addressing several open questions. The PI also plans to perform simulations of astrophysical objects; specifically, the stability of new types of differentially rotating neutron stars. Finally, the PI will implement these methods for numerical relativity in curvilinear coordinates in efficient and scalable community codes, namely the Einstein Toolkit and Harm3D, so that these techniques can be applied in a number of astrophysical simulations that cannot be performed with current stand-alone codes.

爱因斯坦的广义相对论描述了宇宙中所有的引力相互作用，从将掉落的苹果拉向地球的力，到宇宙本身的膨胀。广义相对论的方程--爱因斯坦方程--相当复杂，只有在非常特殊和不现实的情况下，才能用铅笔和纸精确地解出来。模拟更现实的场景-例如为了理解由两个合并的黑洞发射并被LIGO引力波天文台探测到的引力波信号-需要计算机模拟。该小组正在进行的研究工作旨在为这种计算机模拟开发方法和途径。近年来，PI开发了新的方法，非常适合一类新的问题，这可能使当前的模拟显着更有效。在接下来的几年里，他计划采用这些方法来研究在背洞形成开始时发生的所谓“临界现象”，检查快速旋转中子星的性质，并与同事合作，使上述新方法在公共社区代码中可用。本科生将参与这些活动，为他们提供“动手”的研究经验，并在鲍登学院创造一个研究丰富的学习环境。在数值相对论这项研究工作的科学目标包括数值算法的发展和实施的解决爱因斯坦的广义相对论方程，以及它们在相对论对象的数值建模中的应用，特别是中子星和黑洞。在下一个资助期间，PI计划采用球极坐标中的数值相对论方法，以前在NSF赠款下开发，研究引力物理学和相对论天体物理学中的几个问题，特别是使用这个代码来研究没有球对称的临界坍缩。 PI计划扩展早期的结果，研究角动量和非球面变形对完美流体、标量场和真空时空引力坍缩中临界现象的影响，解决几个悬而未决的问题。 PI还计划对天体物理学对象进行模拟;特别是新型差分旋转中子星的稳定性。最后，PI将在高效和可扩展的社区代码中实现这些曲线坐标中的数值相对论方法，即Einstein Toolkit和Harm 3D，以便这些技术可以应用于许多无法使用当前独立代码执行的天体物理模拟。