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arXiv · hep-ph/9608405

Cosmological Axion Problem in Chaotic Inflationary Universe

S. Kasuya·M. Kawasaki·T. Yanagida
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Abstract

We investigate two cosmological axion problems (isocurvature fluctuations and domain-wall formation) in chaotic inflationary universe. It is believed that these problems are solved if potential for the Peccei-Quinn scalar field is very flat. However, we find that too many domain walls are produced through parametric resonance decay of the Peccei-Quinn scalar field. Only the axion model with N=1(N: QCD anomaly factor) is consistent with observations. We also point out that the flat potential is naturally obtained in a supersymmetric extension of the Peccei-Quinn model. If Peccei-Quinn breaking scale $F_a$ is about 10^{12} GeV, this model predicts anisotropies of cosmic microwave background radiation due to the axion isocurvature fluctuations which may be detectable in future observations.

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S. Kasuya, M. Kawasaki, T. Yanagida. 1997-05-16. Cosmological Axion Problem in Chaotic Inflationary Universe. https://doi.org/10.1016/s0370-2693(97)00809-5

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