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arXiv · hep-ph/9703261

Are Isocurvature Fluctuations of the M-theory Axion Observable?

M. Kawasaki·T. Yanagida
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Abstract

Banks and Dine have recently shown that the M theory naturally accommodates the Peccei-Quinn axion. Since the decay constant $F_a$ of the axion is large as $F_a \simeq 10^{15}-10^{16}$GeV, the halo axion is hardly detected in coming axion-search experiments. However, we show that isocurvature fluctuations of the M-theory axion produced at the inflationary epoch are most likely detectable in future satellite experiments on anisotropies of the cosmic microwave background radiation.

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M. Kawasaki, T. Yanagida. 1997-03-07. Are Isocurvature Fluctuations of the M-theory Axion Observable?. https://doi.org/10.1143/ptp.97.809

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