A Note on Calm Excited States of Inflation

Abstract

We identify a two-parameter family of excited states within slow-roll inflation for which either the corrections to the two-point function or the characteristic signatures of excited states in the three-point function -- i.e. the enhancement for the flattened momenta configurations-- are absent. These excited states may nonetheless violate the adiabaticity condition maximally. We dub these initial states of inflation calm excited states. We show that these two sets do not intersect, i.e., those that leave the power-spectrum invariant can be distinguished from their bispectra, and vice versa. The same set of calm excited states that leave the two-point function invariant for slow-roll inflation, do the same task for DBI inflation. However, at the level of three-point function, the calm excited states whose flattened configuration signature is absent for slow-roll inflation, will lead to an enhancement for DBI inflation generally, although the signature is smaller than what suggested by earlier analysis. This example also illustrates that imposing the Wronskian condition is important for obtaining a correct estimate of the non-Gaussian signatures.

v1: 13 pages; v2: matched the JCAP version

References in corpus (19)

• The Effective Field Theory of Inflation
• Observational Signatures and Non-Gaussianities of General Single Field Inflation
• Primordial Non-Gaussianities from Inflation Models
• Generation and Characterization of Large Non-Gaussianities in Single Field Inflation
• Enhanced Non-Gaussianity from Excited Initial States
• Non-Gaussianities in two-field inflation
• Primordial perturbations and non-Gaussianities in DBI and general multi-field inflation
• The Inflationary Trispectrum for Models with Large Non-Gaussianities
• Folded Resonant Non-Gaussianity in General Single Field Inflation
• Non-gaussianity from the trispectrum in general single field inflation
• Large non-Gaussianity from multi-brid inflation
• Minimum Length Cutoff in Inflation and Uniqueness of the Action
• Multifield DBI Inflation and Non-Gaussianities
• Energy Transfer in Multi Field Inflation and Cosmological Perturbations
• The pre-inflationary vacuum in the cosmic microwave background
• CMB quadrupole suppression: I. Initial conditions of inflationary perturbations
• On the Tensor/Scalar Ratio in Inflation with UV Cutoff
• Systematics of multi-field effects at the end of warped brane inflation
• Towards multi-field D-brane inflation in a warped throat

Cited by in corpus (18)

• Trans-Planckian censorship, inflation and excited initial states for perturbations
• Parity-Odd and Even Trispectrum from Axion Inflation
• Symmetry Constraints in Inflation, $\alpha$-vacua, and the Three Point Function
• Non-Gaussianity in single field models without slow-roll
• Pre-inflationary primordial perturbations
• Multiple Soft Limits of Cosmological Correlation Functions
• Soft limits in holographic cosmology
• On the Initial State and Consistency Relations
• Production of non-gaussianities in a bouncing phase
• Scale-dependent hemispherical asymmetry from general initial state during inflation
• Vacua and correlators in hyperbolic de Sitter space
• Non-Gaussian Shape Discrimination with Spectroscopic Galaxy Surveys
• A Flat Space Analogue for the Quantum Origin of Structure
• Non-Gaussianities in the Extended EFT of Inflation
• Looking for non-Gaussianity in all the right places: A new basis for non-separable bispectra
• Inflationary non-Gaussianities in alpha vacua and consistency with conformal symmetries
• Inflationary Cosmology with Quantum Gravitational Effects and the Swampland Conjectures
• Stochastic gravitational wave background anisotropies from inflation with non-Bunch-Davies states