Local Observation in Eternal inflation

Understand

We consider landscape models that admit several regions where the conditions for eternal inflation hold.

• It is shown that one can use the no-boundary wave function to calculate small departures from homogeneity within our past light cone despite the possibility of much larger fluctuations on super horizon scales.
• The dominant contribution comes from the history exiting eternal inflation at the lowest value of the potential.
• In a class of landscape models this predicts a tensor to scalar ratio of about 10%.