On the oscillation-driven cosmological expansion at the post-inflation stage

TL;DR

This paper investigates how oscillating inflaton fields influence the universe's expansion after inflation, providing formulas for late-time behavior and discussing stability and fragmentation of these oscillations.

Contribution

It offers new asymptotic formulas for post-inflationary expansion driven by oscillating inflaton fields and analyzes their stability and fragmentation.

Findings

Derived asymptotic formulas for late-time expansion.

Analyzed stability of oscillations.

Discussed field fragmentation phenomena.

Abstract

Dynamics of the inflaton scalar field oscillating around a minimum of the singular potentials in the expanding Universe is investigated. Asymptotic formulas are obtained describing the cosmological expansion at the late times. The problem of stability of the oscillations considered and the related phenomenon of the field fragmentation are briefly discussed.