Testing alternative theories of gravity using the Sun

TL;DR

This paper introduces a method to test alternative gravity theories using solar physics, specifically analyzing how Eddington-inspired gravity affects solar structure and observations to set constraints on the theory.

Contribution

It demonstrates how solar models and observations can be used to constrain Eddington-inspired gravity, providing a new astrophysical test for modified gravity theories.

Findings

Constraints on the coupling parameter |kappa_g| < 3x10^5 m^5 s^2 / kg

Modified gravity affects solar core temperature and neutrino fluxes

Sun-based tests can effectively limit alternative gravity theories

Abstract

We propose a new approach to test possible corrections to Newtonian gravity using solar physics. The high accuracy of current solar models and new precise observations allow one to constrain corrections to standard gravity at unprecedented levels. Our case study is Eddington-inspired gravity, an attractive modified theory of gravity which results in non-singular cosmology and collapse. The theory is equivalent to standard gravity in vacuum, but it sensibly differs from it within matter, for instance it affects the evolution and the equilibrium structure of the Sun, giving different core temperature profiles, deviations in the observed acoustic modes and in solar neutrino fluxes. Comparing the predictions from a modified solar model with observations, we constrain the coupling parameter of the theory, |kappa_g| < 3x10^5 m^5 s^2 / kg. Our results show that the Sun can be used to efficiently constraint alternative theories of gravity.