Folded Resonant Non-Gaussianity in General Single Field Inflation

Abstract

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. Our full results, including the resonant and folded resonant non-Gaussianities, give the leading order bispectra due to general periodic features in general single field inflation.

13 pages; v3, minor revision with clarification remarks, JCAP version

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Cited by in corpus (13)

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• Resonant Trispectrum and a Dozen More Primordial N-point functions
• Non-Gaussianity in single field models without slow-roll
• Strong scale dependent bispectrum in the Starobinsky model of inflation
• Non-Gaussianities of Single Field Inflation with Non-minimal Coupling
• An optimal estimator for resonance bispectra in the CMB
• Particle creation from the quantum stress tensor
• Minimal cut-off vacuum state constraints from CMB bispectrum statistics
• The scalar bi-spectrum during preheating in single field inflationary models
• Primordial Features as Evidence for Inflation