Post-Newtonian celestial mechanics in scalar-tensor cosmology
Abstract
Applying the recently developed dynamical perturbation formalism on cosmological background to scalar-tensor theory, we provide a solid theoretical basis and a rigorous justification for phenomenological models of orbital dynamics that are currently used to interpret experimental measurements of the time-dependent gravitational constant. We derive the field equations for the scalar-tensor perturbations and study their gauge freedom associated with the cosmological expansion. We find a new gauge eliminating a prohibitive number of gauge modes in the field equations and significantly simplifying post-Newtonian equations of motion for localized astronomical systems in the universe with time-dependent gravitational constant. We identify several new post-Newtonian terms and calculate their effect on secular cosmological evolution of the osculating orbital elements.
Keywords
Cite
@article{arxiv.1606.09139,
title = {Post-Newtonian celestial mechanics in scalar-tensor cosmology},
author = {Andrei Galiautdinov and Sergei M. Kopeikin},
journal= {arXiv preprint arXiv:1606.09139},
year = {2017}
}
Comments
7 pages, no figures; supplemental materials added: "Derivation of the wave equations for perturbations", 27 pages, no figures