AUTHOR=Choi Ki-Young , Kim Jihn E. , Kyae Bumseok 

TITLE=Perspective on completing natural inflation

JOURNAL=Frontiers in Physics

VOLUME=Volume 2 - 2014

YEAR=2015

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2014.00083

DOI=10.3389/fphy.2014.00083

ISSN=2296-424X

ABSTRACT=We present a perspective on the inflation paths in $2-, 3-, \cdots, N-$flation models based on the ultraviolet completion in heterotic string theory, where a number of grand unification scale axions are used. The number of non-Abelian gauge groups for a natural inflation is restricted in string compactification, and we argue that the most plausible completion of natural inflation from a theory perspective  is the 2-- and 3--flation.