A Sun-like star orbiting a boson star

Abstract

The high-precision astrometric mission GAIA recently reported the remarkable discovery of a Sun-like star closely orbiting a dark object, with a semi-major axis and period of $1.4\mathrm{AU}$ and $187.8$ days respectively. While the plausible expectation for the central dark object is a black hole, the evolutionary mechanism leading to the formation of such a two-body system is highly challenging. Here, we challenge the scenario of a central black hole and show that the observed orbital dynamics can be explained under fairly general assumptions if the central dark object is a stable clump of bosonic particles of spin-0, or spin-1, known as a boson star. We further explain how future astrometric measurements of similar systems will provide an exciting opportunity to probe the fundamental nature of compact objects and test compact alternatives to black holes.

11 pages, 4 figures. Comments are very welcome

References in corpus (5)

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Cited by in corpus (6)

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• Extreme-mass-ratio inspirals into rotating boson stars: nonintegrability, chaos, and transient resonances
• Scalaroca stars: coupled scalar-Proca solitons
• Probing vector gravitational atoms with eccentric intermediate mass-ratio inspirals
• Modelling Gaia photometry signals of dark halos
• There and back again: Outspiraling motion in non-Kerr compact objects