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arXiv · 1711.04704

Evolution of thick domain walls in inflationary and $p=wρ$ universe

A. D. Dolgov·S. I. Godunov·A. S. Rudenko
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Abstract

We study the evolution of thick domain walls in the different models of cosmological inflation, in the matter-dominated and radiation-dominated universe, or more generally in the universe with the equation of state $p=wρ$. We have found that the domain wall evolution crucially depends on the time-dependent parameter $C(t)=1/(H(t)δ_0)^2$, where $H(t)$ is the Hubble parameter and $δ_0$ is the thickness of the wall in flat space-time. For $C(t)>2$ the physical thickness of the wall, $a(t)δ(t)$, tends with time to $δ_0$, which is microscopically small. Otherwise, when $C(t) \leq 2$, the wall steadily expands and can grow up to a cosmologically large size.

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A. D. Dolgov, S. I. Godunov, A. S. Rudenko. 2018-08-16. Evolution of thick domain walls in inflationary and $p=wρ$ universe. https://doi.org/10.1140/epjc%2Fs10052-018-6350-7

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