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arXiv · 1907.01561

Distinguishing black holes from horizonless objects through the excitation of resonances during inspiral

Vitor Cardoso·Adrian del Rio·Masashi Kimura
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Abstract

How well is the vacuum Kerr geometry a good description of the dark, compact objects in our universe? Precision measurements of accreting matter in the deep infrared and gravitational-wave measurements of coalescing objects are finally providing answers to this question. Here, we study the possibility of resonant excitation of the modes of the central object -- taken to be very compact but horizonless -- during an extreme-mass-ratio inspiral. We show that for very compact objects resonances are indeed excited. However, the impact of such excitation on the phase of the gravitational-wave signal is negligible, since resonances are crossed very quickly during inspiral.

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Vitor Cardoso, Adrian del Rio, Masashi Kimura. 2019-07-02. Distinguishing black holes from horizonless objects through the excitation of resonances during inspiral. https://doi.org/10.1103/physrevd.100.084046

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