Future Dark Energy Constraints from Atomic Clocks

TL;DR

Atomic clock measurements offer a highly sensitive method to constrain scalar tensor dark energy models within the Solar System, significantly limiting the parameter space of viable theories.

Contribution

This paper introduces a novel approach linking atomic clock variations to dark energy scalar dynamics, providing the strongest local bounds on the dark energy equation of state.

Findings

Constraints exclude broad classes of scalar dark energy models.

Results favor Lambda CDM or decoupled scalar fields as viable models.

Combined data from lunar laser ranging and photon trajectories strengthen bounds.

Abstract

We show that atomic clock measurements provides an exceptionally sensitive Solar System probe of scalar tensor dark energy. By connecting variations in Newton's constant and differential clock drifts to the dynamics of a single dark energy scalar, we derive a direct constraint on the present day equation of state and our results force any locally coupled scalar dark energy into a very slowly rolling regime, giving the strongest bounds on the equation of state parameter. This is independent of potential shape or kinetic structure and rules out broad classes of canonical and non canonical models, leaving only near Lambda CDM behavior or fully decoupled fields as viable late time scalar dark energy, thereby leaving cosmological constant and minimally coupled scalar field models as the most consistent dark energy regimes. We also use results from Lunar Laser Ranging and photon trajectories to further strengthen our the depth of our constraints.