Sharp predictions from eternal inflation patches in the string landscape

Who: Thomas Hertog (University of Leuven)
When: Monday, December 7, 2015 at 14:15
Where: The CP³ meeting room

The application of the laws of quantum mechanics to the universe as a whole is known as quantum cosmology. The central theoretical ingredient in quantum cosmology is a `wave function of the universe which implies a measure on the space of initial conditions in cosmology. I first sketch the general framework of quantum cosmology, including recent developments that show how one obtains predictions for our local observations starting from a wave function of the universe.

I then illustrate the general framework in a specific corner of the string landscape, the landscape of warped D3-brane inflation, for a universe in the no-boundary quantum state. The no-boundary measure favours universes that emerge from patches of eternal inflation in this landscape. I show this leads to sharp predictions for the spectral properties of primordial perturbations on observable scales, in contrast with the broadly distributed probabilities if one adopts a flat prior on initial conditions.