We present fully general relativistic simulations of the quasicircular inspiral and merger of charged, nonspinning, binary black holes with chargetomass ratio λ≤0.3. We discuss the key features that enabled long term and stable evolutions of these binaries. We also present a formalism for computing the angular momentum carried away by electromagnetic waves, and the electromagnetic contribution to blackhole horizon properties. We implement our formalism and present the results for the first time in numericalrelativity simulations. In addition, we compare our full nonlinear solutions with existing approximate models for the inspiral and ringdown phases. We show that Newtonian models based on the quadrupole approximation have errors of 20 %  100 % in key gaugeinvariant quantities. On the other hand, for the systems considered, we find that estimates of the remnant black hole spin based on the motion of test particles in KerrNewman spacetimes agree with our nonlinear calculations to within a few percent. Finally, we discuss the prospects for detecting black hole charge by future gravitationalwave detectors using either the inspiralmergerringdown signal or the ringdown signal alone.
This content will become publicly available on January 1, 2023
Extremal black holes that are not extremal: maximal warm holes
A bstract We study a family of fourdimensional, asymptotically flat, charged black holes that develop (charged) scalar hair as one increases their charge at fixed mass. Surprisingly, the maximum charge for given mass is a nonsingular hairy black hole with nonzero Hawking temperature. The implications for Hawking evaporation are discussed.
 Award ID(s):
 2107939
 Publication Date:
 NSFPAR ID:
 10322657
 Journal Name:
 Journal of High Energy Physics
 Volume:
 2022
 Issue:
 1
 ISSN:
 10298479
 Sponsoring Org:
 National Science Foundation
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