Constraints on scalar–tensor theory of gravity by solar system tests

Abstract

AbstractWe study the motion of particles in the background of a scalar–tensor theory of gravity in which the scalar field is kinetically coupled to the Einstein tensor. We constrain the value of the derivative parameter z through solar system tests. By considering the perihelion precession we obtain the constraint $$\sqrt{z}/m_{\mathrm{p}} > 2.6\times 10^{12}$$ z / m p > 2.6 × 10 12  m, the gravitational redshift $$\frac{\sqrt{z}}{m_{\mathrm{p}}}>2.7\times 10^{\,10}$$ z m p > 2.7 × 10 10  m, the deflection of light $$\sqrt{z}/m_{\mathrm{p}} > 1.6 \times 10^{11}$$ z / m p > 1.6 × 10 11  m, and the gravitational time delay $$\sqrt{z}/m_{\mathrm{p}} > 7.9 \times 10^{12}$$ z / m p > 7.9 × 10 12  m; thereby, our results show that it is possible to constrain the value of the z parameter in agreement with the observational tests that have been considered.