A Cosmological Bootstrap for Resonant Non-Gaussianity

Abstract

Recent progress has revealed a number of constraints that cosmological correlators and the closely related field-theoretic wavefunction must obey as a consequence of unitarity, locality, causality and the choice of initial state. When combined with symmetries, namely homogeneity, isotropy and scale invariance, these constraints enable one to compute large classes of simple observables, an approach known as (boostless) cosmological bootstrap. Here we show that it is possible to relax the restriction of scale invariance, if one retains a discrete scaling subgroup. We find an infinite class of solutions to the weaker bootstrap constraints and show that they reproduce and extend resonant non-Gaussianity, which arises in well-motivated models such as axion monodromy inflation. We find no evidence of the new non-Gaussian shapes in the Planck data. Intriguingly, our results can be re-interpreted as a deformation of the scale-invariant case to include a complex order of the total energy pole, or more evocatively interactions with a complex number of derivatives. We also discuss for the first time IR-divergent resonant contributions and highlight an inconsequential inconsistency in the previous literature.

33 pages, 4 figures; v2: published version, minor corrections and references added

References in corpus (15)

• The Effective Field Theory of Inflation
• Monodromy in the CMB: Gravity Waves and String Inflation
• Starting the Universe: Stable Violation of the Null Energy Condition and Non-standard Cosmologies
• Generation and Characterization of Large Non-Gaussianities in Single Field Inflation
• An Ignoble Approach to Large Field Inflation
• Folded Resonant Non-Gaussianity in General Single Field Inflation
• Oscillations in the inflaton potential?
• Combining power spectrum and bispectrum measurements to detect oscillatory features
• Resonant Trispectrum and a Dozen More Primordial N-point functions
• How Gaussian can our Universe be?
• A Differential Representation of Cosmological Wavefunctions
• Higher N-point function data analysis techniques for heavy particle production and WMAP results
• On Graviton non-Gaussianities in the Effective Field Theory of Inflation
• High-resolution CMB bispectrum estimator with flexible modal basis
• Observable Quantum Loop Effects in the Sky

Cited by in corpus (11)

• Inflationary Butterfly Effect: Non-perturbative Dynamics From Small-Scale Features
• The Open Effective Field Theory of Inflation
• Searching for Cosmological Collider in the Planck CMB Data
• The Massive Flat Space Limit of Cosmological Correlators
• Bispectrum at 1-loop in the Effective Field Theory of Inflation
• The UV Sensitivity of Axion Monodromy Inflation
• Bunch-Davies initial conditions and non-perturbative inflationary dynamics in Numerical Relativity
• A Match Made in Heaven: Linking Observables in Inflationary Cosmology
• Perturbative unitarity bounds on field-space curvature in de Sitter spacetime: purity vs scattering amplitude
• Amplifying the Cosmological Collider with Ghost Spectators
• Non-relativistic Cosmological Collider Signals