Speaker: William Cottrell, University of Wisconsin
Abstract: Attempts to provide a UV complete model for inflation generically encounter large quantum corrections which spoil the flatness of the inflaton potential. A standard method to work around this, known as 'natural inflation' attempts to use axions as inflatons since they enjoy a perturbative shift symmetry and thus can naturally have very flat potentials. However, we will argue that such theories of inflation are ruled out by the weak gravity conjecture. More precisely, we will show that models with natural inflation are analogous to theories which allow black hole remnants and are thus highly disfavored.