Extended Inflation with an Exponential Potential

TL;DR

This paper explores extended inflation with an exponential potential, showing it predicts a uniform distribution of the Planck mass across universes and supports eternal inflation consistent with observed values.

Contribution

It introduces a simple exponential potential model for extended inflation that predicts a uniform Planck mass distribution and demonstrates the occurrence of eternal inflation under broad conditions.

Findings

Predicts a uniform distribution of the Planck mass after inflation

Eternal inflation occurs for a wide range of initial conditions

Predicted Planck mass aligns with observed value within parameter ranges

Abstract

In this paper we investigate extended inflation with an exponential potential $V(\sigma)= V_0 e^{-\kappa\sigma}$, which provides a simple cosmological scenario where the distribution of the constants of Nature is mostly determined by $\kappa$. In particular, we show that this theory predicts a uniform distribution for the Planck mass at the end of inflation, for the entire ensemble of universes that undergo stochastic inflation. Eternal inflation takes place in this scenario for a broad family of initial conditions, all of which lead up to the same value of the Planck mass at the end of inflation. The predicted value of the Planck mass is consistent with the observed value within a comfortable range of values of the parameters involved.