Features of the inflaton potential and the power spectrum of cosmological perturbations

TL;DR

This paper explores how specific features in the inflaton potential can significantly amplify the power spectrum of cosmological perturbations, potentially leading to primordial black holes and distinctive gravitational wave patterns.

Contribution

It demonstrates that steep decreases in the inflaton potential can cause large enhancements in the power spectrum and discusses implications for supergravity models.

Findings

Steep potential decreases amplify the power spectrum by several orders of magnitude.

Enhanced spectra can produce primordial black holes.

Features induce oscillatory patterns in gravitational wave spectra.

Abstract

We discuss features of the inflaton potential that can lead to a strong enhancement of the power spectrum of curvature perturbations. We show that a steep decrease of the potential induces an enhancement of the spectrum by several orders of magnitude, which may lead to the production of primordial black holes. The same feature can also create a distinctive oscillatory pattern in the spectrum of gravitational waves generated through the scalar perturbations at second order. We study the additive effect of several such features. We analyse a simplified potential, but also discuss the possible application to supergravity models.