More hilltop inflation models

TL;DR

This paper analytically explores the parameter space of hilltop inflation models with specific potentials, showing how they can match observed spectral index values and offering insights into their theoretical viability.

Contribution

It introduces a detailed analytical framework for hilltop inflation models with potentials of the form V_0 ± m^2φ^2 - aφ^p, connecting model parameters with observational data.

Findings

Hilltop models can match the observed spectral index n=0.95

Certain parameter choices are theoretically favored

Models predict |n-1| ≤ 1 in general

Abstract

Using analytic expressions, we explore the parameter space for hilltop inflation models with a potential of the form $V_0\pm m^2\phi^2 -a\phi^p$. With the positive sign and p>2 this converts the original hybrid inflation model into a hilltop model, allowing the spectral index to agree with the observed value n=0.95. In some cases the observed value is theoretically favored, while in others there is only the generic prediction $|n-1|\lsim 1$.