Corpus ID: 235353038

Natural Inflation After Planck 2018

  title={Natural Inflation After Planck 2018},
  author={Nina K. Stein and W. Kinney},
Abstract. We calculate high-precision constraints on Natural Inflation relative to current observational constraints from Planck 2018 + BICEP/Keck(BK15) Polarization + BAO on r and nS , including post-inflationary history of the universe. We find that, for conventional post-inflationary dynamics, Natural Inflation with a cosine potential is disfavored at greater than 95% confidence out by current data. If we assume protracted reheating characterized by w > 1/3, Natural Inflation can be brought… Expand

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