Tidal dynamics of black holes and self-force in strong gravitational fields

强引力场中黑洞的潮汐动力学和自力

• 批准号: 171367-2013
• 负责人: Poisson, Eric
• 金额: $ 1.82万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=633355
• 关键词: Tidal; dynamics; black; holes; self

The proposal is divided into two broad streams, the tidal dynamics of black holes, and the self-force in spacetimes with matter. Binary systems of black holes are among the most promising and exciting sources of gravitational waves, and the tidal forces exerted on one black hole by its companion can have a strong impact on the dynamics of the binary system when its orbit is very tight, close to merger. For example, the tidal forces can torque the black hole and produce a change of spin, and they can heat the black hole and produce a change of mass; these processes affect the orbital motion and the form of the gravitational waves emitted by the system. These signatures can be measured and used to test the detailed predictions of general relativity concerning black holes. In the next granting cycle I will work toward obtaining a much better understanding of this tidal dynamics, focusing mostly on the astrophysically realistic case of rotating black holes. The self-force refers to a deviation from geodesic motion that occurs when a particle moving in spacetime can no longer be considered to be a test body. This happens, for example, when the particle carries an electric charge; in this case the charge produces an electromagnetic field that interacts with the ambiant spacetime curvature, and the field gives rise to a net force acting on the particle. This also happens when the particle's mass is sufficiently large that it affects the structure of spacetime around it; the gravitational perturbation creates an effective force that prevents the particle from moving on a geodesic of the background spacetime. In the next granting cycle I will continue my work on the electromagnetic and gravitational self-force. In particular, I will determine whether the self-force can act as a cosmic censor, preventing a black hole from being destroyed by absorbing a charged particle that would drive its charge beyond the allowed limit.

这个提议分为两大部分，黑洞的潮汐动力学和物质在时空中的自作用力。黑洞的双星系统是最有希望和最令人兴奋的引力波源之一，当它的轨道非常紧密，接近合并时，它的同伴施加在一个黑洞上的潮汐力可以对双星系统的动力学产生强烈的影响。例如，潮汐力可以扭转黑洞并产生自旋变化，它们可以加热黑洞并产生质量变化;这些过程影响轨道运动和系统发射的引力波的形式。这些特征可以被测量，并用于检验广义相对论关于黑洞的详细预测。在下一个授予周期中，我将致力于更好地理解这种潮汐动力学，主要集中在旋转黑洞的天体物理现实情况。自作用力指的是当一个在时空中运动的粒子不再被认为是一个测试体时发生的测地线运动的偏离。例如，当粒子带有电荷时，就会发生这种情况;在这种情况下，电荷会产生一个与周围时空曲率相互作用的电磁场，而这个场会产生一个作用在粒子上的净力。当粒子的质量大到足以影响周围时空的结构时，也会发生这种情况;引力摄动产生了一个有效力，阻止粒子在背景时空的测地线上运动。在下一个授予周期中，我将继续我在电磁和引力自力方面的工作。特别是，我将确定自作用力是否可以充当宇宙审查器，防止黑洞因吸收带电粒子而被摧毁，带电粒子将使其电荷超过允许的限度。