Why Must Primordial Non-Gaussianity Be Very Small?
Jason Kristiano, Jun’ichi Yokoyama
Abstract
One-loop correction to the power spectrum in generic single-field inflation is calculated by using standard perturbation theory. Because of the enhancement inversely proportional to the observed red tilt of the spectral index of curvature perturbation, the correction turns out to be much larger than previously anticipated. As a result, the primordial non-Gaussianity must be much smaller than the current observational bound in order to warrant the validity of cosmological perturbation theory.
Topics & Concepts
PhysicsSpectral indexPerturbation (astronomy)Spectral densityCurvatureCosmological perturbation theoryInflation (cosmology)Primordial black holeCosmologyAstrophysicsClassical mechanicsUpper and lower boundsTheoretical physicsQuantum electrodynamicsWarrantInstabilityPrimordial fluctuationsPerturbation theory (quantum mechanics)Tilt (camera)Statistical physicsSpectral lineFluctuation spectrumObservational cosmologySpectral shape analysisCMB cold spotSlow rollCosmology and Gravitation TheoriesGalaxies: Formation, Evolution, PhenomenaAstronomy and Astrophysical Research