Speaker
Description
The tidal response of black holes (BHs) encodes key information about gravity in the strong-field regime and directly affects gravitational waveforms from binary inspirals. We study the dynamical tidal response of static, spherically symmetric BHs in the low-frequency regime, where analytic techniques provide valuable insights. Using the Regge–Wheeler equation and the Mano–Suzuki–Takasugi (MST) method, we derive the small-frequency expansion of BH perturbations and match the results to the worldline effective field theory (EFT) framework.
This matching enables us to extract the conservative part of the dynamical tidal response, known as dynamical tidal Love numbers, and to clarify their renormalization properties within general relativity (GR). We confirm the universal flow under renormalization but also identify ambiguities in the finite part, which depend on the renormalization scheme or initial conditions.
Our framework naturally extends to compare BHs in GR with other compact objects or predictions from alternative gravitational theories. The notion of “bare” tidal Love numbers provides a means to distinguish such scenarios and could leave detectable imprints on inspiral waveforms. Incorporating these effects into post-Newtonian waveform modeling offers a new avenue to probe compact object structure and to test GR in the strong-field regime.
