Probing Extreme Gravity with Gravitational Waves
Kent Yagi (Virginia)
November 03, 2017
Abstract: Compact binary merger events recently discovered by the LIGO and Virgo Collaboration offer us excellent testbeds for exploring extreme (strong and dynamical-field) gravity that was previously inaccessible. In this talk, I will first review the current status of testing such gravity with these events, in particular, explaining how well one can probe various fundamental pillars in General Relativity. I will then describe what comes next in terms of testing gravity with gravitational waves. Regarding black-hole based tests of gravity, I will discuss how one can stack multiple ringdown events to probe black hole no-hair property. Regarding neutron star based tests of gravity, I will use approximate universal relations (“I-Love-Q relations”) among certain neutron star observables that are almost insensitive to the unknown stellar internal structure, and describe how one can extract extreme gravity information with multimessenger astronomy. I will conclude with a summary of important future directions.