Axionlike Origin of the Primordial Density Perturbation.

  title={Axionlike Origin of the Primordial Density Perturbation.},
  author={Takeshi Kobayashi},
  journal={Physical review letters},
  volume={125 1},
We show that an axionlike field coupled to a new confining gauge group can generate the primordial density perturbation in the postinflation 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… 
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