Radion Inflation in Higher-Dimensional Gravity Theory

TL;DR

This paper proposes a radion-based inflation model derived from five-dimensional gravity, demonstrating it can naturally produce the observed cosmological data with minimal parameters and no fine-tuning.

Contribution

It introduces a radion inflation model from 5D gravity that naturally fits observational data without fine-tuning, highlighting its simplicity and viability.

Findings

The radion potential exhibits slow-roll properties suitable for inflation.

The model reproduces all precision astrophysical data without fine-tuning.

It involves a small number of parameters, making it economical and predictive.

Abstract

We study a radion model for inflation and density perturbation identifying the scalar field arising from the five-dimensional gravity on $M_4 x S^1$ with the inflaton. The inflaton potential arising from 5D graviton and matter one-loop effects is shown to possess the desirable slow-roll property. This radion model contains only a small number of parameters and there is an ample parameter region which reproduces (without fine-tuning) all precision astrophysical data.