Folded Resonant Non-Gaussianity in General Single Field Inflation

Understand

We compute a novel type of large non-Gaussianity due to small periodic features in general single field inflationary models.

• We show that the non-Bunch-Davies vacuum component generated by features, although has a very small amplitude, can have significant impact on the non-Gaussianity.
• Three mechanisms are turned on simultaneously in such models, namely the resonant effect, non-Bunch-Davies vacuum and higher derivative kinetic terms, resulting in a bispectrum with distinctive shapes and running.
• The size can be equal to or larger than that previously found in each single mechanism.