Effective potential of scalar-tensor gravity with quartic self-interaction of scalar field

TL;DR

This paper calculates the one-loop effective potential for scalar-tensor gravity with a quartic scalar field interaction, revealing instabilities in strong fields and potential applications in inflationary cosmology.

Contribution

It provides the first evaluation of the effective potential at first post-Minkowskian order, highlighting conditions for stability and inflationary dynamics.

Findings

Potential develops instabilities in strong fields

Model can achieve slow-roll inflation with specific parameters

Instability regions can be exponentially distant in strong field regimes

Abstract

One-loop effective potential of scalar-tensor gravity with a quartic scalar field self-interaction is evaluated up to first post-Minkowskian order. The potential develops an instability in the strong field regime which is expected from an effective theory. Depending on model parameters the instability region can be exponentially far in a strong field region. Possible applications of the model for inflationary scenarios are highlighted. It is shown that the model can enter the slow-roll regime with a certain set of parameters.