# Natural Inflation After Planck 2018

@inproceedings{Stein2021NaturalIA, title={Natural Inflation After Planck 2018}, author={Nina K. Stein and W. Kinney}, year={2021} }

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

#### One Citation

Natural-Scalaron Inflation

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A pseudo Nambu-Goldstone boson (such as an axion-like particle) is a theoretically well-motivated inflaton as it features a naturally flat potential (natural inflation). This is because Goldstone’s… Expand

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