RUI: Studies in Numerical Relativity

RUI：数值相对论研究

• 批准号: 2308821
• 负责人: Thomas Baumgarte
• 金额: $ 27万
• 依托单位: Bowdoin College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2308821&HistoricalAwards=false
• 关键词: RUI; Studies; Numerical; Relativity

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. In particular, this theory describes black holes and neutron stars — so-called "compact objects" that have extremely strong gravitational fields. The goal of this award is to study what happens when such an object collides with a larger star: would such a collision be observable, would the remnant of the collision form a new type of star, or would it collapse to form another black hole, possibly in an unusual mass range? Answers to these questions will help shed light on the abundance of compact objects, including very small black holes that may have formed in the early Universe and that may contribute to its dark-matter content, and will help understand recent observations by the LIGO gravitational wave detectors of black holes with unusual masses. Finding these answers requires the tools of numerical relativity, i.e. computer programs that can find solutions to Einstein’s equations of general relativity numerically. 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 these research efforts 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 these activities will focus on so-called "Thorne-Zytkow-like-Objects", i.e. larger "host" stars that harbor smaller compact objects as "parasites". Examples include neutron stars that harbor small black holes, possibly of primordial origin, white dwarfs that harbor neutron stars, and main sequence stars that harbor black holes or neutron stars. Specific research activities will explore processes by which these objects may form, including capture and/or binary merger, and will determine whether or not they are dynamically stable, whether their co-evolution and ultimate collapse results in observable gravitational-wave or electromagnetic signals, and whether these scenarios provide viable evolutionary pathways to black holes outside the mass ranges resulting from standard stellar evolution.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.

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，从把一个落下的苹果拉向地球的力，到宇宙本身的膨胀。 特别是，这个理论描述了黑洞和中子星-所谓的“紧凑物体”，具有极强的引力场。 这个奖项的目的是研究当这样一个物体与一个更大的星星碰撞时会发生什么：这样的碰撞是可以观察到的吗？碰撞的残余物会形成一种新的星星吗？还是会坍缩形成另一个黑洞，可能在一个不寻常的质量范围内？ 这些问题的答案将有助于揭示致密物体的丰富性，包括可能在早期宇宙中形成的非常小的黑洞，这可能有助于其暗物质含量，并将有助于理解LIGO引力波探测器最近对具有不寻常质量的黑洞的观测。 找到这些答案需要数值相对论的工具，即计算机程序，可以找到爱因斯坦广义相对论方程的数值解。 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。这些研究工作的科学目标包括发展和实施爱因斯坦广义相对论方程的数值算法，以及它们在相对论物体数值建模中的应用，特别是中子星和黑洞。 在下一个资助期内，这些活动将集中在所谓的“Thorne-Zytkow-like-Objects”上，即较大的“宿主”恒星，其中含有较小的紧凑物体作为“寄生物”。 例子包括有可能是原始起源的小黑洞的中子星，有中子星的白色矮星，以及有黑洞或中子星的主序星。 具体的研究活动将探索这些物体可能形成的过程，包括俘获和/或二元合并，并将确定它们是否动态稳定，它们的共同演化和最终坍缩是否导致可观测到的引力波或电磁信号，以及这些情景是否为标准恒星演化产生的质量范围之外的黑洞提供了可行的演化途径。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估的支持。

项目成果

Critical Phenomena in the Collapse of Gravitational Waves

引力波坍缩的关键现象

• DOI: 10.1103/physrevlett.131.181401
• 发表时间: 2023
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Baumgarte, Thomas W.;Brügmann, Bernd;Cors, Daniela;Gundlach, Carsten;Hilditch, David;Khirnov, Anton;Ledvinka, Tomáš;Renkhoff, Sarah;Fernández, Isabel Suárez
• 通讯作者: Fernández, Isabel Suárez

Could long-period transients be powered by primordial black hole capture?

长周期瞬变能否由原初黑洞捕获提供动力？

• DOI: 10.1103/physrevd.109.063004
• 发表时间: 2024
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Baumgarte, Thomas W.;Shapiro, Stuart L.
• 通讯作者: Shapiro, Stuart L.