Non-gaussianities and the Stimulated creation of quanta in the inflationary universe

Abstract

Cosmological inflation generates a spectrum of density perturbations that can seed the cosmic structures we observe today. These perturbations are usually computed as the result of the gravitationally-induced spontaneous creation of perturbations from an initial vacuum state. In this paper, we compute the perturbations arising from gravitationally-induced stimulated creation when perturbations are already present in the initial state. The effect of these initial perturbations is not diluted by inflation and survives to its end, and beyond. We consider a generic statistical density operator $\rho$ describing an initial mixed state that includes probabilities for nonzero numbers of scalar perturbations to be present at early times during inflation. We analyze the primordial bispectrum for general configurations of the three different momentum vectors in its arguments. We find that the initial presence of quanta can significantly enhance non-gaussianities in the so-called squeezed limit. Our results show that an observation of non-gaussianities in the squeezed limit can occur for single-field inflation when the state in the very early inflationary universe is not the vacuum, but instead contains early-time perturbations. Valuable information about the initial state can then be obtained from observations of those non-gaussianities.

25 pages

References in corpus (9)

• Enhanced Non-Gaussianity from Excited Initial States
• Enhanced polarization of CMB from thermal gravitational waves
• CMB quadrupole suppression: I. Initial conditions of inflationary perturbations
• A new method for calculating the primordial bispectrum in the squeezed limit
• The Creation of Particles in an Expanding Universe
• Non-Gaussianity as a Probe of the Physics of the Primordial Universe and the Astrophysics of the Low Redshift Universe
• Amplitude of Perturbations from Inflation
• Study of the Spectrum of Inflaton Perturbations
• Observing the temperature of the Big Bang through large scale structure

Cited by in corpus (128)

• Loop Quantum Cosmology: A Status Report
• Large-Scale Galaxy Bias
• A Short Review of Loop Quantum Gravity
• On Soft Limits of Inflationary Correlation Functions
• The pre-inflationary dynamics of loop quantum cosmology: Confronting quantum gravity with observations
• A Quantum Gravity Extension of the Inflationary Scenario
• An Extension of the Quantum Theory of Cosmological Perturbations to the Planck Era
• Trans-Planckian Issues for Inflationary Cosmology
• A Single Field Inflation Model with Large Local Non-Gaussianity
• Exploring Cosmic Origins with CORE: Inflation
• Quantum Discord of Cosmic Inflation: Can we Show that CMB Anisotropies are of Quantum-Mechanical Origin?
• The (not so) squeezed limit of the primordial 3-point function
• Symmetries and Loops in Inflation
• Observable traces of non-metricity: new constraints on metric-affine gravity
• Signatures of anisotropic sources in the squeezed-limit bispectrum of the cosmic microwave background
• Calculating the local-type fNL for slow-roll inflation with a non-vacuum initial state
• Scale-dependent bias of galaxies and mu-type distortion of the cosmic microwave background spectrum from single-field inflation with a modified initial state
• Loop quantum cosmology: From pre-inflationary dynamics to observations
• Reconciliation of High Energy Scale Models of Inflation with Planck
• Inflation with General Initial Conditions for Scalar Perturbations
• In-in and $\delta N$ calculations of the bispectrum from non-attractor single-field inflation
• On Squeezed Limits in Single-Field Inflation - Part I
• Rescuing Single Field Inflation from the Swampland
• CMB Power Asymmetry from Non-Gaussian Modulation
• Alleviating the Tension in the Cosmic Microwave Background using Planck-Scale Physics
• Consistently violating the non-Gaussian consistency relation
• δN Formalism in Anisotropic Inflation and Large Anisotropic Bispectrum and Trispectrum
• Loop quantum cosmology, non-Gaussianity, and CMB power asymmetry
• Trans-Planckian censorship, inflation and excited initial states for perturbations
• Primordial backgrounds of relic gravitons
• Sloan Digital Sky Survey III Photometric Quasar Clustering: Probing the Initial Conditions of the Universe using the Largest Volume
• Large and strong scale dependent bispectrum in single field inflation from a sharp feature in the mass
• Non-Gaussianity from Excited Initial Inflationary States
• Non-Gaussianity Consistency Relations, Initial States and Back-reaction
• On the scalar consistency relation away from slow roll
• Large non-Gaussian Halo Bias from Single Field Inflation
• Anisotropic Inflation with the non-Vacuum Initial State
• Non-Gaussianity in Loop Quantum Cosmology
• The Open Effective Field Theory of Inflation
• Experimental Observation of Acceleration-Induced Thermality
• Perturbative Reheating After Multiple-Field Inflation: The Impact on Primordial Observables
• Strong scale dependent bispectrum in the Starobinsky model of inflation
• Cosmological Consequences of Initial State Entanglement
• Constraining the initial conditions of the Universe using large scale structure
• Non-Gaussianities in the Cosmological Perturbation Spectrum due to Primordial Anisotropy
• Non-Gaussianities in the Cosmological Perturbation Spectrum due to Primordial Anisotropy II
• Extended Effective Field Theory of Inflation
• Quantum-gravity effects for excited states of inflationary perturbations
• Stimulated creation of quanta during inflation and the observable universe
• Loop Quantum Cosmology: A brief review
• Pre-slow roll initial conditions: large scale power suppression and infrared aspects during inflation
• Multiple Soft Limits of Cosmological Correlation Functions
• Could PBHs and secondary GWs have originated from squeezed initial states?
• Non-adiabatic Evolution of Primordial Perturbations and non-Gaussinity in Hybrid Approach of Loop Quantum Cosmology
• An optimal estimator for resonance bispectra in the CMB
• Primordial non-Gaussianity and power asymmetry with quantum gravitational effects in loop quantum cosmology
• Loop Quantum Gravity Phenomenology: Linking Loops to Observational Physics
• Large Scale Anisotropic Bias from Primordial non-Gaussianity
• Soft limits in holographic cosmology
• On the Initial State and Consistency Relations
• Probing correlations of early magnetic fields using mu-distortion
• A Consistency Relation for Single-Field Inflation with Power Spectrum Oscillations
• Primordial tensor non-Gaussianities from general single-field inflation with non-Bunch-Davies initial states
• Scale-dependent power spectrum from initial excited-de Sitter modes
• Tensor to scalar ratio and large scale power suppression from pre-slow roll initial conditions
• Probing the initial state of inflation: analytical structure of cosmological correlators
• Modifications to Cosmological Power Spectra from Scalar-Tensor Entanglement and their Observational Consequences
• Hemispherical Anomaly from Asymmetric Initial States
• Bispectrum from open inflation
• New Shapes of Primordial Non-Gaussianity from Quasi-Single Field Inflation with Multiple Isocurvatons
• Predictions for the CMB from an anisotropic quantum bounce
• Observational consequences of Bianchi I spacetimes in loop quantum cosmology
• Revisiting non-Gaussianity in non-attractor inflation models in the light of the cosmological soft theorem
• The scale-dependent signature of primordial non-Gaussianity in the large-scale structure of cosmic reionization
• Reconstructing the Primary CMB Dipole
• Loop Quantum Cosmology
• Primordial non-Gaussianities in single field inflationary models with non-trivial initial states
• Enhanced local-type inflationary trispectrum from a non-vacuum initial state
• Hamiltonian theory of classical and quantum gauge invariant perturbations in Bianchi I spacetimes
• Removing the ISW-lensing bias from the local-form primordial non-Gaussianity estimation
• Anisotropic non-Gaussianity from Rotational Symmetry Breaking Excited Initial States
• Optimal CMB estimators for bispectra from excited states
• The Odd-Parity Galaxy Bispectrum
• Squeezed primordial bispectrum from general vacuum state
• Non-Bunch-Davies Anisotropy
• Symmetry Reduced Loop Quantum Gravity: A Bird's Eye View
• Cosmological cutting rules for Bogoliubov initial states
• Accelerated electron thermometer: observation of 1D Planck radiation
• What initial condition of inflation would suppress the large-scale CMB spectrum?
• Weyl invariance and the conductivity of the protoinflationary plasma
• Power Spectrum and Non-Gaussianities in Anisotropic Inflation
• Scale-dependent hemispherical asymmetry from general initial state during inflation
• Vacua and correlators in hyperbolic de Sitter space
• Thermal power spectrum in the CFT driven cosmology
• The symmetries of inflationary magnetogenesis and the plasma initial conditions
• Why does the effective field theory of inflation work?
• No-hair conjectures, primordial shear and protoinflationary initial conditions
• Fluid phonons, protoinflationary dynamics and large-scale gravitational fluctuations
• A Flat Space Analogue for the Quantum Origin of Structure
• Effect of intermediate Minkowskian evolution on CMB bispectrum
• Non-Gaussianities in the Extended EFT of Inflation
• Non-Gaussianity from Entanglement During Inflation
• Higher Order Corrections to Asymptotic-de Sitter Inflation
• Generic 3-point Statistics with Tensor Modes in Light of Swampland and TCC
• Quantum Entanglement in Multi-field Inflation
• Violation of consistency relations and the protoinflationary transition
• Looking for non-Gaussianity in all the right places: A new basis for non-separable bispectra
• Exploring local fNL estimators based on the binned bispectrum
• Dynamical Response of an Unruh-DeWitt Detector in a Quantum Field over the History of the Universe
• Quantum Particle Production Effects on Cosmic Expansion
• Inflationary non-Gaussianities in alpha vacua and consistency with conformal symmetries
• Fluid phonons and inflaton quanta at the protoinflationary transition
• Loop corrections to primordial non-Gaussianity
• Influence of Unobservable Modes on Correlation Functions during Inflation
• Inflation in Non-de Sitter Background with Coherent States
• Loop Quantum Gravity and the The Planck Regime of Cosmology
• CMB statistical anisotropies of classical and quantum origins
• Mode coupling on a geometrodynamical quantization of an inflationary universe
• Cosmological consequences of statistical inhomogeneity
• Secondary graviton spectra, second-order correlations and Bose-Einstein enhancement
• A Proposal for Constraining Initial Vacuum by CMB
• Exploring Inflationary Initial State With Large Scale Structure Observations
• Spontaneous particle creation by oscillating compact stars
• Stochastic gravitational wave background anisotropies from inflation with non-Bunch-Davies states
• Cosmic tango between the very small and the very large: Addressing CMB anomalies through Loop Quantum Cosmology
• Thermodynamics of irreversible particle creation phenomena and its cosmological consequence
• Effects of Radiation on Primordial Non-Gaussianity
• Primordial magnetic non-Gaussianity with generic vacua and detection prospects in CMB spectral distortions