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arXiv · 1508.06547

Curvature Perturbation and Domain Wall Formation with Pseudo Scaling Scalar Dynamics

Yohei Ema·Kazunori Nakayama·Masahiro Takimoto
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Abstract

Cosmological dynamics of scalar field with a monomial potential $ϕ^{n}$ 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.

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Yohei Ema, Kazunori Nakayama, Masahiro Takimoto. 2016-03-09. Curvature Perturbation and Domain Wall Formation with Pseudo Scaling Scalar Dynamics. https://doi.org/10.1088/1475-7516%2F2016%2F02%2F067

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