Constraining the range of Yukawa gravity interaction from S2 star orbits III: improvement expectations for graviton mass bounds

TL;DR

This paper explores how future observations of star orbits near the Galactic Center could tighten constraints on the graviton mass, potentially surpassing current bounds from gravitational wave detections by analyzing orbital precession.

Contribution

It proposes a method to improve graviton mass bounds using future star orbit data, assuming general relativity accurately predicts orbital precession.

Findings

Potential to constrain graviton mass to ~5 x 10^{-23} eV

Future star orbit observations could surpass current gravitational wave bounds

Assumes future observations will confirm GR predictions for orbital shifts

Abstract

Recently, the LIGO-Virgo collaboration discovered gravitational waves and in their first publication on the subject the authors also presented a graviton mass constraint as $m_g < 1.2 \times 10^{-22}$ eV (Abbott et al., 2016). In the paper we analyze a potential to reduce upper bounds for graviton mass with future observational data on trajectories of bright stars near the Galactic Center. Since gravitational potentials are different for these two cases, expressions for relativistic advance for general relativity and Yukawa potential are different functions on eccentricity and semimajor axis, it gives an opportunity to improve current estimates of graviton mass with future observational facilities. In our considerations of an improvement potential for a graviton mass estimate we adopt a conservative strategy and assume that trajectories of bright stars and their apocenter advance will be described with general relativity expressions and it gives opportunities to improve graviton mass constraints. In contrast with our previous studies, where we present current constraints on parameters of Yukawa gravity (Borka et al., 2013) and graviton mass (Zakharov et al., 2016) from observations of S2 star, in the paper we express expectations to improve current constraints for graviton mass, assuming the GR predictions about apocenter shifts will be confirmed with future observations. We concluded that if future observations of bright star orbits during around fifty years will confirm GR predictions about apocenter shifts of bright star orbits it give an opportunity to constrain a graviton mass at a level around $5 \times 10^{-23}$ eV or slightly better than current estimates obtained with LIGO observations.