Constraints on scalar-tensor theories from observations

TL;DR

This paper analyzes scalar-tensor gravity models with exponential and power-law potentials, testing their compatibility with observational data, and finds both models support an accelerating universe with a dynamic dark energy component.

Contribution

It provides the first comprehensive observational constraints on scalar-tensor theories with specific potential forms, highlighting their viability for explaining cosmic acceleration.

Findings

Both models predict an accelerating universe.

Dark energy behaves as a time-dependent equation of state.

Models are consistent with current observational data.

Abstract

We study the dynamical description of scalar-tensor gravity by performing the best-fit analysis for two cases of exponential and power-law form of the potential and scalar field function coupled to the curvature. The models are then tested against observational data. The results show that in both scenarios the Universe undergoes an acceleration expansion period and the geometrical equivalent of dark energy is associated with a time-dependent equation of state.