Aligned Natural Inflation: Monodromies of two Axions

Abstract

Natural (axionic) inflation can accommodate sizeable primordial tensor modes but suffers from the necessity of trans-Planckian variations of the inflaton field. This problem can be solved via the mechanism of aligned axions arXiv:hep-ph/0409138, where the aligned axion spirals down in the potential of other axions. We elaborate on the mechanism in view of the recently reported observations of the BICEP2 collaboration arXiv:1403.3985.

Comments: 11 pages, 3 figures, v2: typos corrected, references added, v3: references added, matches published version