# Inflationary scenario from higher curvature warped spacetime

## TL;DR

This paper explores how higher curvature terms in a five-dimensional warped spacetime can induce an inflationary phase in the early universe, with predictions consistent with Planck 2015 observations.

## Contribution

It demonstrates that higher curvature corrections generate a radion potential leading to inflation in a Randall-Sundrum model, aligning theoretical predictions with observational data.

## Key findings

- Radion potential arises from higher curvature terms.
- Early universe undergoes accelerated expansion ending in finite time.
- Predicted spectral index and tensor-to-scalar ratio match Planck 2015 data.

## Abstract

We consider a five dimensional AdS spacetime, in presence of higher curvature term like $F(R) = R + \alpha R^2$ in the bulk, in the context of Randall-Sundrum two-brane model. Our universe is identified with the TeV scale brane and emerges as a four dimensional effective theory. From the perspective of this effective theory, we examine the possibility of "inflationary scenario" by considering the on-brane metric ansatz as an FRW one. Our results reveal that the higher curvature term in the five dimensional bulk spacetime generates a potential term for the radion field. Due to the presence of radion potential, the very early universe undergoes a stage of accelerated expansion and moreover the accelerating period of the universe terminates in a finite time. We also find the spectral index of curvature perturbation ($n_s$) and tensor to scalar ratio ($r$) in the present context, which match with the observational results based on the observations of $Planck$ $2015$.