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arXiv · 2005.01741

Axionlike Origin of the Primordial Density Perturbation

Takeshi Kobayashi
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Abstract

We show that an axionlike field coupled to a new confining gauge group can generate the primordial density perturbation in the post-inflation universe. The axion decay constant and strong coupling scale are uniquely determined by observations of the density perturbation, which further suggest a temporal deconfinement of the gauge group after inflation. The resulting temperature-dependent axion potential, together with its periodic nature, gives rise to the red-tilted density perturbation, with a positive local-type non-Gaussianity of order unity.

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Takeshi Kobayashi. 2020-07-02. Axionlike Origin of the Primordial Density Perturbation. https://doi.org/10.1103/physrevlett.125.011302

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