2019/06/16 by Jonathan Thornburg, Barry Wardell, Maarten van de Meent · 1 voice · 1 citation
Engineering · Physics and Astronomy · #Amplitude #Angular momentum #Astrophysical Phenomena and Observations #Astrophysics #Black hole (networking) #Classical mechanics #Condensed matter physics #Excitation #Geophysics and Sensor Technology #Gravitational wave #Mass ratio #Materials science #Orbit (dynamics) #Physics #Pulsars and Gravitational Waves Research #Quantum electrodynamics #Quantum mechanics #Quasinormal mode #Range (aeronautics) #Rotating black hole #Spins #Vibration #gr-qc
paper · pdf · doi:10.1103/physrevresearch.2.013365
published as Phys. Rev. Research 2, 013365 (2020) · 26 pages, 12 color pdf figures and 6 color png bitmap figures, full-resolution versions of png bitmap figures included as ancillary files in anc/ directory; revised in response to referee comments and to specifically note the occurence of wiggles for retrograde orbits
arxiv published 2019/06/16 · arxiv created 2019/11/09 · openalex publication_date 2020/03/25 · arxiv updated 2020/04/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
If a small compact object orbits a black hole, it is known that it can excite the black hole's quasinormal modes (QNMs), leading to high-frequency oscillations ("wiggles") in the radiated field at J+, and in the radiation-reaction self-force acting on the object after its orbit passes through periapsis. Here we survey the phenomenology of these wiggles across a range of black hole spins and equatorial orbits. In both the scalar-field and gravitational cases we find that wiggles are a generic feature across a wide range of parameter space, and that they are observable in field perturbations at fixed spatial positions, in the self-force, and in radiated fields at J+. For a given charge or mass of the small body, the QNM excitations have the highest amplitudes for systems with a highly spinning central black hole, a prograde orbit with high eccentricity, and an orbital periapsis close to the light ring. The QNM amplitudes depend smoothly on the orbital parameters, with only very small amplitude changes when the orbit's (discrete) frequency spectrum is tuned to match QNM frequencies. The association of wiggles with QNM excitations suggest that they represent a situation where the nonlocal nature of the self-force is particularly apparent, with the wiggles arising as result of QNM excitation by the compact object near periapsis, and then encountered later in the orbit. Astrophysically, the effects of wiggles at J+ might allow direct observation of Kerr QNMs in extreme-mass-ratio inspiral (EMRI) binary black hole systems, potentially enabling new tests of general relativity.