Speaker
Description
Tidal interactions can significantly impact the dynamics of binary systems and their gravitational-wave signals. In particular, for extreme-mass-ratio inspirals (EMRIs), a fully relativistic description is required to capture the interplay between spin, curvature, and orbital dynamics in the strong-field regime.
We study the response of a Kerr black hole to external tidal fields and its implications for EMRIs. Using metric reconstruction in the Newman-Penrose formalism, we obtain analytic solutions of the Teukolsky equation for static, quadrupolar vacuum perturbations and reconstruct the corresponding metric.
As an application, we derive a secular Hamiltonian governing the long-term dynamics of a test particle in a tidally deformed Kerr spacetime. In particular, we compute tidal-induced shifts of the innermost stable circular orbit and the light ring, and analyze their dependence on the black hole's spin. These results provide an analytic framework for tidal interactions in Kerr spacetimes, directly applicable to EMRI modelling and gravitational-wave physics.