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arXiv · 1804.03297

A "no-hair" test for binary black holes

Siddharth Dhanpal·Abhirup Ghosh·Ajit Kumar Mehta·Parameswaran Ajith·B. S. Sathyaprakash
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Abstract

One of the consequences of the black-hole "no-hair" theorem in general relativity (GR) is that gravitational radiation (quasi-normal modes) from a perturbed Kerr black hole is uniquely determined by its mass and spin. Thus, the spectrum of quasi-normal mode frequencies have to be all consistent with the same value of the mass and spin. Similarly, the gravitational radiation from a coalescing binary black hole system is uniquely determined by a small number of parameters (masses and spins of the black holes and orbital parameters). Thus, consistency between different spherical harmonic modes of the radiation is a powerful test that the observed system is a binary black hole predicted by GR. We formulate such a test, develop a Bayesian implementation, demonstrate its performance on simulated data and investigate the possibility of performing such a test using previous and upcoming gravitational wave observations.

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Siddharth Dhanpal, Abhirup Ghosh, Ajit Kumar Mehta, Parameswaran Ajith, B. S. Sathyaprakash. 2018-04-10. A "no-hair" test for binary black holes. https://doi.org/10.1103/physrevd.99.104056

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