Eugene Lim - April 13, 2018

"How Robust is Inflation to Inhomogenous Initial Conditions?"

Abstract : Inflation solved the cosmic homogeneity problem. But does Inflation itself 
require a homogenous patch to begin? We investigate this problem in full 3+1 
numerical relativity. We show that while large field inflation is very robust to inhomogeneities,
 small field inflation fails in the presence of sub-dominant gradients of the inflaton. 
Furthermore, we explore, for the first time large inhomogenous metric perturbations
 such as tensor perturbations and mixed collapsing/expanding initial conditions. 
Finally,  we show that, for large field inflation, attempts to stop inflation by forming
a black hole spacetime will fail as long as the initial hyperslice is roughly flat.