发表机构
Arizona State University; Princeton University; Sapienza Università di Roma; INFN, Sezione di Roma; Universidade de Lisboa – UL; Niels Bohr Institute（亚利桑那州立大学; 普林斯顿大学; 罗马第一大学; 意大利国家核物理研究所罗马分部; 里斯本大学; 尼尔斯·玻尔研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文计算了黑洞附近引力波的非线性二阶散射响应，发现其在驱动频率匹配基本准正则模时最强，且二次耦合系数随频率二次方缩放，并揭示了低频下的非线性潮汐形变能力。
AI 中文摘要
引力波在黑洞附近以非线性方式耦合。黑洞微扰理论可以方便地用于计算这种耦合的幅度、其对入射引力波的宇称内容、频率和角结构的依赖关系。在本工作中，我们进行了这一计算，表明引力波的非线性耦合通常在驱动频率与黑洞基本准正则模的振荡频率匹配时达到峰值。我们还证明了这种激发在允许的最大谐波处最强，并且它仅轻微依赖于入射模式的宇称内容。在低频下，这里计算的二次响应编码了黑洞时空本身的非线性、动力学潮汐形变能力。我们数值上证明了二次黑洞耦合系数随驱动频率二次方缩放，并从5点康普顿引力子散射振幅中恢复了这一缩放关系。
英文摘要
Gravitational waves couple in a nonlinear fashion in the vicinity of a black hole. Black hole perturbation theory can be readily applied to compute the magnitude of this coupling, its dependence on the parity content, frequencies, and angular structure of the incoming gravitational waves. In this work we carry out this calculation, showing how the nonlinear coupling of gravitational waves generically peaks when the driven frequency matches the oscillation frequency of the fundamental quasinormal mode of the black hole. We also demonstrate how this excitation is largest at the maximal harmonics allowed, and study its dependence on the parity content of the incoming modes. At low frequencies, the quadratic response computed here encodes the nonlinear, dynamical tidal deformability of the black hole spacetime itself. We demonstrate numerically that the quadratic black hole coupling coefficient scales quadratically with the driving frequency, and recover this scaling from the 5-point Compton graviton scattering amplitude.
Commentsv2. Corrected error in metric reconstruction gauge term, and added new time-domain validation of our results
