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arXiv · 1902.06748

Exotic compact object behavior in black hole analogues

Carlos A. R. Herdeiro·Nuno M. Santos
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Abstract

Classical phenomenological aspects of acoustic perturbations on a draining bathtub geometry where a surface with reflectivity $\mathcal{R}$ is set at a small distance from the would-be acoustic horizon, which is excised, are addressed. Like most exotic compact objects featuring an ergoregion but not a horizon, this model is prone to instabilities when $|\mathcal{R}|^2\approx 1$. However, stability can be attained for sufficiently slow drains when $|\mathcal{R}|^2\lesssim70\%$. It is shown that the superradiant scattering of acoustic waves is more effective when their frequency approaches one of the system's quasi-normal mode frequencies.

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BibTeXRIS

Carlos A. R. Herdeiro, Nuno M. Santos. 2019-02-18. Exotic compact object behavior in black hole analogues. https://doi.org/10.1103/physrevd.99.084029

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