Gravitation and Black Holes: From Magnetospheres to Firewalls

这项研究旨在提高对引力物理三个不同领域的理解：1)将量子力学应用于黑洞时出现的令人困惑的问题；2)测试可能偏离标准相对论的情况；3)天体物理黑洞和其他系统中的强磁场理论。在第二个主题上，一个项目涉及在修正的引力理论中计算球状塌缩恒星和超新星的引力波的预测形式。另一个是研究这种理论在量子领域的可行性，第三个是开发替代的但类似的量子引力方法。第三类主题包括天体物理喷流的性质，以及从黑洞和恒星中提取能量，这些黑洞和恒星在带电粒子的磁化云中旋转或运动。此外，本工作还研究了重力对扭曲磁力线的产生和性质的影响，以及基本方程的数学结构和计算机模拟。所有这些方法都解决了有关宇宙结构的基本问题。将通过书面文章以及研讨会、会议讲座、座谈和系列讲座来传播相应的成果。PI将为博士后学者以及研究生和本科生提供科学研究、写作和口头交流方面的指导和指导。PI将寻找机会就这一主题向从普通公众到引力物理专家的各种听众发表演讲。在量子引力领域，一个项目涉及黑洞信息悖论以及惠勒-德维特方程在解决该悖论中的可能作用。具体地说，这项工作研究了将信息冗余编码成满足Wheeler-de Witt方程的波函数所描述的局部自由度。另一个项目涉及黑洞熵与真空纠缠和Noether电荷的关系。这项研究将试图确定在涉及穿越黑洞视界的物质的绝热物理过程中，非最小耦合对熵的贡献是否被相应的纠缠熵变化所平衡。在Lorentz违反引力的问题上，本项目研究了在非线性水平上考虑所有高阶导数项的情况下，提出的UV完备的Lifshitz量子引力能否通过稳定性检验。我们还将研究Lifshitz标度的想法是否可以应用于具有首选的时间线条但没有首选的空间分层的时空。最后，磁层专题将集中于在一般相对论环境中以及在中子星表面或黑洞视界等边界存在的情况下对磁螺旋度的定义、计算和解释。这对于在一般相对论环境中确定螺旋度注入和守恒的作用，以及它与能量最小化的关系应该是有用的。

This research is directed at developing an improved understanding in three different areas of gravitational physics: 1) puzzling issues that arise when applying quantum mechanics to black holes, 2) tests of possible deviations from standard relativity theory, 3) theory of strong magnetic fields around astrophysical black holes and in other systems. On the second topic, one project involves calculating the predicted form of gravitational waves from spherical collapsing stars and supernovae in a modified gravity theory. Another is a study of the viability of such a theory in the quantum realm, and a third is to develop alternative but similar approaches to quantum gravity. Topics in the third category include the nature of astrophysical jets, and energy extraction from black holes and stars spinning or moving in a magnetized cloud of charged particles. Also, this work studies the impact of gravity on the generation and properties of twisted magnetic field lines, and the mathematical structure of the basic equations and their simulation on computers. All of these approaches address fundamental questions regarding the structure of the universe. The corresponding results will be disseminated through written articles, as well as seminars, conference talks, colloquia and lecture series. The PI will provide instruction and mentoring to a postdoctoral scholar, as well as graduate and undergraduate students, regarding scientific research, writing, and verbal communication. The PI will seek out opportunities to speak on this topic to audiences ranging across the spectrum from the general public to specialists in gravitational physics.In the quantum gravity realm, one project concerns the black hole information paradox and the possible role of the Wheeler-de Witt equation in resolving it. Specifically, this work studies the redundant encoding of information into the local degrees of freedom described by a wave function satisfying the Wheeler-de Witt equation. Another project involves the relation of black hole entropy to vacuum entanglement and Noether charge. This research will try to determine whether the entropy contribution from non minimal coupling is balanced by a corresponding entanglement entropy change in adiabatic physical processes involving matter crossing black hole horizons. On the Lorentz violating gravity topic, this project studies whether the proposal for a UV complete, "Lifshitz" quantum gravity can pass the stability test, when all the higher derivative terms are taken into account at the non-linear level. We will also examine whether the idea of Lifshitz scaling can be applied in a spacetime with a preferred temporal threading but no preferred spatial foliation. Finally, the magnetosphere topics are will concentrate on the definition, computation and interpretation of magnetic helicity in a general relativistic setting, and in the presence of boundaries such as the surface of a neutron star or the horizon of a black hole. This should be useful in determining the role of helicity injection and conservation, and how it relates to energy minimization, in a general relativistic setting.