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arXiv · 2311.08031

Constraints on metric-affine gravity black holes from the stellar motion at the Galactic Center

Ivan De Martino·Riccardo Della Monica·Diego Rubiera-Garcia
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Abstract

We consider a static, spherically symmetric space-time with an electric field arising from a quadratic metric-affine extension of General Relativity. Such a space-time is free of singularities in the centre of the black holes, while at large distances it quickly boils down to the usual Reissner-Nordstr\"om solution. We probe this space-time metric, which is uniquely characterized by two length scales, $r_q$ and $\ell$, using the astrometric and spectroscopic measurements of the orbital motion of the S2 star around the Galactic Center. Our analysis constrains $r_q$ to be below $2.7M$ for values $\ell<120 AU$, strongly favouring a central object that resembles a Schwarzschild black hole.

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Ivan De Martino, Riccardo Della Monica, Diego Rubiera-Garcia. 2023-11-14. Constraints on metric-affine gravity black holes from the stellar motion at the Galactic Center. https://doi.org/10.1103/physrevd.109.024016

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