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arXiv · 2206.12699

Constraining MOdified Gravity with the S2 Star

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

We have used publicly available kinematic data for the S2 star to constrain the parameter space of MOdified Gravity. Integrating geodesics and using a Markov Chain Monte Carlo algorithm we have provided with the first constraint on the scales of the Galactic Centre for the parameter $\alpha$ of the theory, which represents the fractional increment of the gravitational constant $G$ with respect to its Newtonian value. Namely, $\alpha \lesssim 0.662$ at 99.7% confidence level (where $\alpha = 0$ reduces the theory to General Relativity).

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Riccardo Della Monica, Ivan de Martino, Mariafelicia de Laurentis. 2022-06-25. Constraining MOdified Gravity with the S2 Star. https://doi.org/10.3390/universe8020137

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