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arXiv · 2105.12687

Orbital precession of the S2 star in Scalar-Tensor-Vector-Gravity

Riccardo Della Monica·Ivan de Martino·Mariafelicia de Laurentis
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Abstract

We have obtained the first constraint of the parameter space of Scalar-Tensor-Vector-Gravity using the motion of the S2-star around the supermassive black hole at the centre of the Milky Way, and we did not find any serious tension with General Relativity. We used the Schwarzschild-like metric of Scalar-Tensor-Vector-Gravity to predict the orbital motion of S2-star, and to compare it with the publicly available astrometric data, which include 145 measurements of the positions, 44 measurements of the radial velocities of S2-star along its orbit, and the recent measurement of the orbital precession. We employed a Monte Carlo Markov Chain algorithm to explore the parameter space, and constrained the only one additional parameter of Scalar-Tensor-Vector-Gravity to $α\lesssim 0.410$ at 99,7$\%$ confidence level, where $α=0$ reduces this modified theory of gravity to General Relativity.

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Riccardo Della Monica, Ivan de Martino, Mariafelicia de Laurentis. 2021-05-26. Orbital precession of the S2 star in Scalar-Tensor-Vector-Gravity. https://doi.org/10.1093/mnras%2Fstab3727

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