Inflation in the Space of Initial Conditions

A Bumpy Start to a Smooth Ride: Onset of Inflation amid Backreaction from Inhomogeneities

We analyze the onset of inflation for a simple single-field model when the system begins with significant inhomogeneities on length-scales shorter than the initial hubble radius.We incorporate certain nonlinear interactions among the coupled degrees of freedom by using the nonperturbative hartree approximation.We find inflation to be robust for large-field models, even when the system begins with significant structure on sub-hubble-scales.We consider the space of initial conditions where is the vacuum expectation value of the quantum field that drives inflation.Although some regions of that would have yielded sufficient inflation in the absence of inhomogeneities fail to do so when backreaction from inhomogeneities is incorporated, an equal volume of such regions succeeds in producing sufficient inflation which did not do so in the absence of inhomogeneities.