Speaker: Elisa Maggio (Max Planck Institute, AEI Potsdam)
Host: Davide Gerosa
Testing general relativity with recent gravitational-wave observations
The coalescence of black-hole binaries provides a unique arena for testing general relativity in the strong-field and dynamical regime. Of particular interest is the ringdown phase, where the newly formed remnant black hole settles into a stationary state. This phase is governed by characteristic oscillations known as quasinormal modes, whose frequencies and damping times are determined solely by the remnant’s mass and spin. These modes serve as a fingerprint of the black hole and a direct test of whether it conforms to the Kerr solution predicted by general relativity.
In this talk, we explore GW250114 as the loudest gravitational wave detected to date, and highlight how advanced detectors enable increasingly stringent constraints on deviations from Einstein’s theory. We also examine GW230814, the loudest signal in the latest gravitational-wave catalog, showing an apparent deviation from general relativity in the ringdown. We discuss the impact of systematic errors in waveform models and detector noise effects in tests of general relativity, as well as the need for a global network of observatories for robust tests of fundamental physics.