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arXiv · 2202.08848

The irreducible mass and the horizon area of LIGO's black holes

Abstract

The mass of a Kerr black hole can be separated into irreducible and rotational components -the former is a lower limit to the energy that cannot be possibly extracted from the event horizon and is related to its area. Here we compute the irreducible masses of the stellar-mass black holes observed by gravitational-wave interferometers LIGO and Virgo. Using single-event data, we present a re-parametrization of the posterior distribution that explicitly highlights the irreducible and rotational contributions to the total energy. We exploit the area law to rank the black-hole mergers observed to date according to their irreversibility, thus providing a guide to selecting events for targeted tests of General Relativity. Using population fits, we compute the rate by which the total area of black-hole horizons increases due to the observable mergers.

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Davide Gerosa, Cecilia Maria Fabbri, Ulrich Sperhake. 2022-02-17. The irreducible mass and the horizon area of LIGO's black holes. https://doi.org/10.1088/1361-6382%2Fac8332

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