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arXiv · 1909.01604

A Dynamical Solution to the Axion Domain Wall Problem

Masahiro Ibe·Shin Kobayashi·Motoo Suzuki·Tsutomu T. Yanagida
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Abstract

The domain wall problem and the isocurvature problem restrict possible combinations of axion models and inflation models. In this paper, we considered a new mechanism which solves those problems by dynamics of multiple scalar fields during/after inflation. The mechanism makes axion models with a non-trivial domain wall number compatible with inflation models with a large Hubble parameter, $H_{I} \gg 10^{7\mbox{-}8}\,$GeV. The mechanism also avoids the isocurvature problem. This mechanism increases the freedom of choice of combinations of axion models and inflation models.

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Masahiro Ibe, Shin Kobayashi, Motoo Suzuki, Tsutomu T. Yanagida. 2019-09-04. A Dynamical Solution to the Axion Domain Wall Problem. https://doi.org/10.1103/physrevd.101.035029

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