Radion induced inflation on non-flat brane and modulus stabilization

TL;DR

This paper explores how a dynamically stabilized radion field in non-flat brane models can naturally induce inflation in the early universe, with a phantom-like kinetic phase that ends successfully.

Contribution

It introduces a novel radion stabilization mechanism in non-flat brane models that naturally triggers and exits inflation, aligning with observational data.

Findings

Radion potential generated by non-flat branes can induce inflation.

Radion kinetic term exhibits phantom-like behavior during inflation.

Stable radion evolution provides a successful exit from inflation.

Abstract

Warped braneworld models has the potential to provide a plausible resolution to the gauge hierarchy problem but at the cost of introduction of an additional field, namely the inter-brane separation or, the radion field. Providing an appropriate stabilization scheme for the radion field has long been sought for. In this work, we discuss dynamical stabilization of the radion field in the context of early universe cosmology. We show that by allowing the branes to be \emph{non-flat} and \emph{dynamical} a radion potential is naturally generated which can trigger the inflationary phase of the early universe. Interestingly, the kinetic term of the radion during the inflationary epoch exhibits a phantom-like behavior and the dynamical evolution of the radion field to its stable value marks the exit from the phantom phase as well as the inflationary era simultaneously. We show that the amalgamation and synergy of the radion potential along with its kinetic term can not only trigger the inflationary scenario but also provide a successful exit from the same while maintaining concordance with current observation.