Bispectrum from open inflation

by Dr Kazuyuki Sugimura (Paris 7)

Tuesday 3 Sept 2013, 17:30 → 18:30 Europe/Berlin

3343 (Universe)

We calculate the bispectrum of quantum fluctuations in open inflation, where quantum tunneling of an inflaton field from a false vacuum triggers slow-roll inflation inside the nucleated bubble. Assuming that the false vacuum inflation before the quantum tunneling is long enough for the quantum state in such a period to be approximated as the Bunch-Davies vacuum state, we compute the evolution of the state, based on the in-in formalism. Since the state inside the nucleated bubble is different from the one naturally defined for the observer in the bubble, we can study the effect of so-called "non-Bunch-Davies initial state" on the bispectrum in a model where such a state is naturally generated.