Inflationary Steps in the Planck Data

Abstract

We extend and improve the modeling and analysis of large-amplitude, sharp inflationary steps for second order corrections required by the precision of the Planck CMB power spectrum and for arbitrary Dirac-Born-Infeld sound speed. With two parameters, the amplitude and frequency of the resulting oscillations, step models improve the fit by $\Delta {\chi }^2=-11.4$. Evidence for oscillations damping before the Planck beam scale is weak: damping only improves the fit to $\Delta {\chi }^2=-14.0$ for one extra parameter, if step and cosmological parameters are jointly fit, in contrast to analyses which fix the latter. Likewise, further including the sound speed as a parameter only marginally improves the fit to $\Delta {\chi }^2=-15.2$ but has interesting implications for the lowest multipole temperature and polarization anisotropy. Since chance features in the noise can mimic these oscillatory features, we discuss tests from polarization power spectra, lensing reconstruction and squeezed and equilateral bispectra that should soon verify or falsify their primordial origin.

submitted

References in corpus (4)

• CMB polarization features from inflation versus reionization
• Generalized Slow Roll for Non-Canonical Kinetic Terms
• CMB Constraints on Principal Components of the Inflaton Potential
• Fast Computation of First-Order Feature-Bispectrum Corrections

Cited by in corpus (48)

• Planck 2018 results. X. Constraints on inflation
• Features and New Physical Scales in Primordial Observables: Theory and Observation
• Primordial power spectrum from Planck
• Probing primordial features with future galaxy surveys
• Inflation with moderately sharp features in the speed of sound: GSR and in-in formalism for power spectrum and bispectrum
• Amplification of Primordial Perturbations from the Rise or Fall of the Inflaton
• Primordial Features from Linear to Nonlinear Scales
• Scratches from the Past: Inflationary Archaeology through Features in the Power Spectrum of Primordial Fluctuations
• Polyspectra searches for sharp oscillatory features in cosmic microwave sky data
• Evidence for bouncing evolution before inflation after BICEP2
• Steps to Reconcile Inflationary Tensor and Scalar Spectra
• Super-Sample CMB Lensing
• Untangling features in the primordial spectra
• Probing primordial features with next-generation photometric and radio surveys
• Constraints on inflation with LSS surveys: features in the primordial power spectrum
• Towards testing CMB anomalies using the kinetic and polarized Sunyaev Zel'dovich effects
• Consistency relations for sharp features in the primordial spectra
• Searching for features of a string-inspired inflationary model with cosmological observations
• Euclid: The search for primordial features
• Polarization Predictions for Inflationary CMB Power Spectrum Features
• Bayesian analysis of inflationary features in Planck and SDSS data
• Nonlinear Excitations in Inflationary Power Spectra
• Perturbative Unitarity of Inflationary Models with Features
• Resonant particle production during inflation: a full analytical study
• Direct search for features in the primordial bispectrum
• Late time sky as a probe of steps and oscillations in primordial Universe
• Robust predictions for an oscillatory bispectrum in Planck 2015 data from transient reductions in the speed of sound of the inflaton
• Red, Straight, no bends: primordial power spectrum reconstruction from CMB and large-scale structure
• Primordial feature constraints from BOSS+eBOSS
• Primordial power spectrum features in phenomenological descriptions of inflation
• Probing primordial features with the primary CMB
• Consistency relations for sharp inflationary non-Gaussian features
• Generalized Slow Roll for Tensors
• Jump in fluid properties of inflationary universe to reconcile scalar and tensor spectra
• DBI Inflation and Warped Black Holes
• Improving Constraints on Inflation with CMB Delensing
• Detectable Data-driven Features in the Primordial Scalar Power Spectrum
• Enhanced spectrum of primordial perturbations, galaxy formation and small scale structure
• Refining the nonlinear modelling of primordial oscillatory features
• Knot reconstruction of the scalar primordial power spectrum with Planck, ACT, and SPT CMB data
• Potential reconstruction from general power spectrum in single-field inflation
• Probing Inflation with Precision Bispectra
• Bayesian inference methodology for Primordial Power Spectrum reconstructions from Large Scale Structure
• The running of featureful primordial power spectra
• J-PAS: forecast on the primordial power spectrum reconstruction
• Mimicking two field inflationary features with a single field
• Investigation of homogeneity and matter distribution on large scales using large quasar groups
• Consistency of Planck Data With Power-Law Primordial Scalar Power Spectrum