# On natural inflation

@article{Freese2004OnNI, title={On natural inflation}, author={Katherine Freese}, journal={Physical Review D}, year={2004}, volume={70}, pages={083512} }

We reexamine the model of natural inflation, in which the inflaton potential is flat due to shift symmetries. The original version of the model, where the inflaton is a pseudo-Nambu-Goldstone boson with potential of the form V({phi})={lambda}{sup 4}[1{+-}cos({phi}/f)], is studied in light of recent data. We find that the model is alive and well. Successful inflation as well as data from the Wilkinson Microwave Anisotropy Probe require f>0.6m{sub Pl} (where m{sub Pl}=1.22x10{sup 19} GeV) and… Expand

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