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arXiv · 1612.00978

Ultralight scalars and resonances in black-hole physics

Ryuichi Fujita·Vitor Cardoso
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Abstract

Ultralight degrees of freedom coupled to matter lead to resonances, which can be excited when the Compton wavelength of the field equals a dynamical scale in the problem. For binaries composed of a star orbiting a supermassive black hole, these resonances lead to a smoking-gun effect: a periastron distance which {\it stalls}, even in the presence of gravitational-wave dissipation. This effect, also called a {\it floating orbit}, occurs for generic equatorial but eccentric orbits and we argue that finite-size effects are not enough to suppress it.

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Ryuichi Fujita, Vitor Cardoso. 2016-12-03. Ultralight scalars and resonances in black-hole physics. https://doi.org/10.1103/physrevd.95.044016

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