Curvature Perturbation and Domain Wall Formation with Pseudo Scaling Scalar Dynamics

TL;DR

This paper investigates the unique pseudo scaling behavior of scalar fields at a critical potential index, exploring its implications for curvature perturbations and domain wall issues in cosmology.

Contribution

It introduces and analyzes a novel pseudo scaling solution for scalar fields at the critical potential index, filling a gap in understanding scalar dynamics at this boundary.

Findings

Identification of pseudo scaling solution at critical potential index

Implications for curvature perturbation generation in cosmology

Insights into domain wall formation problems

Abstract

Cosmological dynamics of scalar field with a monomial potential $\phi^{n}$ with a general background equation of state is revisited. It is known that if $n$ is smaller than a critical value, the scalar field exhibits a coherent oscillation and if $n$ is larger it obeys a scaling solution without oscillation. We study in detail the case where $n$ is equal to the critical value, and find a peculiar scalar dynamics which is neither oscillating nor scaling solution, and we call it a pseudo scaling solution. We also discuss cosmological implications of a pseudo scaling scalar dynamics, such as the curvature perturbation and the domain wall problem.