Constraints onRngravity from precession of orbits of S2-like stars

Abstract

We study some possible observational signatures of R n gravity at Galactic scales and how these signatures could be used for constraining this type of fðRÞ gravity. For that purpose, we performed twobody simulations in the R n gravity potential and analyzed the obtained trajectories of S2-like stars around the Galactic center, as well as the resulting parameter space of the R n gravity potential. Here, we discuss the constraints on R n gravity which can be obtained from the observations of orbits of S2-like stars with the present and next generations of large telescopes. We make comparisons between the theoretical results and observations. Our results show that the most probable value for the parameter r c in the R n gravity potential in the case of S2-like stars is $100 AU, while the universal parameter is close to 0.01. Also, the gravity potential induces the precession of S2-like star orbits in the opposite direction with respect to general relativity; therefore, such a behavior of orbits is qualitatively similar to the behavior of Newtonian orbits with a bulk distribution of matter (including a stellar cluster and dark matter distributions).

Investigating the Binarity of S0-2: Implications for Its Origins and Robustness as a Probe of the Laws of Gravity around a Supermassive Black Hole

“…As anticipated by many theorists, observations of shortperiod stars orbiting the SMBH in our Galactic center are currently opening a new window into testing the gravitational theory and to measure relativistic effects (see, e.g., Rubilar & Eckart 2001;Zucker et al 2006;Will 2008;Borka et al 2013;Johannsen 2016aJohannsen , 2016bPsaltis et al 2016;Zakharov et al 2016;Iorio 2017 and references therein). The relativistic redshift on S0-2′s RV is the first relativistic effect expected to be detected with S0-2′s closest approach in 2018 (Zucker et al 2006;Angélil & Saha 2010, 2011.…”

Graviton mass evaluation with trajectories of bright stars at the Galactic Center

“…An analysis of S2 like star trajectories gives an opportunity to obtain stringent constraints on alternative theories of gravity, including R n theory which is a generalization of the classical GR and n = 1 corresponds to GR [33,34] (there are also stringent constraints from Solar system data [35]), and Yukawa gravity [36]. In the paper we will obtain a graviton mass constraint from analysis of trajectories of bright stars at the Galactic Center.…”

Shadow size for the supermassive black hole at the Galactic Center

“…One can find a more detailed description of our results in papers 15,21,22,[29][30][31][32][33][34][35] .…”