The $1/N$ expansion for stochastic fields in de Sitter spacetime

Abstract

We propose a $1/N$ expansion of Starobinsky and Yokoyama's effective stochastic approach for light quantum fields on superhorizon scales in de Sitter spacetime. We explicitly compute the spectrum and the eigenfunctions of the Fokker-Planck operator for a O($N$)-symmetric theory with quartic selfinteraction at leading and next-to-leading orders in this expansion. We obtain simple analytical expressions valid in various nonperturbative regimes in terms of the interaction coupling constant.

arXiv comment8 pages, 5 figures

References in corpus (36)

• Equilibrium State of a Massless Self-Interacting Scalar Field in the De Sitter Background
• Stochastic Quantum Gravitational Inflation
• Super-Hubble de Sitter Fluctuations and the Dynamical RG
• Breakdown of Semiclassical Methods in de Sitter Space
• Lecture notes on interacting quantum fields in de Sitter space
• On the proper treatment of massless fields in Euclidean de Sitter space
• Infrared dynamics in de Sitter space from Schwinger-Dyson equations
• Classical approximation to quantum cosmological correlations
• An effective field theory during inflation: reduced density matrix and its quantum master equation
• Effective potential for quantum scalar fields on a de Sitter geometry
• On "dynamical mass" generation in Euclidean de Sitter space
• Feynman Diagrams for Stochastic Inflation and Quantum Field Theory in de Sitter Space
• Nonperturbative resummation of de Sitter infrared logarithms in the large-N limit
• The stochastic spectator
• Effective long wavelength scalar dynamics in de Sitter
• Scalar field correlator in de Sitter space at next-to-leading order in a 1/N expansion
• Observational constraints on quantum decoherence during inflation
• Quantum scalar fields in de Sitter space from the nonperturbative renormalization group
• Renormalization group flow and symmetry restoration in de Sitter space
• IR divergences and kinetic equation in de Sitter space. (Poincare patch; Principal series)
• Decoherence and thermalization of a pure quantum state in quantum field theory
• Infrared resummation for derivative interactions in de Sitter space
• Scalar correlation functions in de Sitter space from the stochastic spectral expansion
• Exact RG Flow in an Expanding Universe and Screening of the Cosmological Constant
• Condensates and quasiparticles in inflationary cosmology: mass generation and decay widths
• Non Gaussianities from Quantum Decoherence during Inflation
• Resummation of infrared logarithms in de Sitter space via Dyson-Schwinger equations: the ladder-rainbow approximation
• Long distance behavior of $O(N)$-model correlators in de Sitter space and the resummation of secular terms
• Functional renormalization group in stochastic inflation
• Physical momentum representation of scalar field correlators in de Sitter space
• Scalar correlation functions for a double-well potential in de Sitter space
• Stochastic evolution of scalar fields with continuous symmetries during inflation
• To the sphere and back again: de Sitter infrared correlators at NTLO in 1/N
• Unequal time correlators of stochastic scalar fields in de Sitter space
• Feynman Rules for Stochastic Inflationary Correlators
• Quantum properties of a non-Gaussian state in the large-N approximation

Cited by in corpus (4)

• A manifestly covariant theory of multifield stochastic inflation in phase space: solving the discretisation ambiguity in stochastic inflation
• Second-order stochastic theory for self-interacting scalar fields in de Sitter spacetime
• Free scalar correlators in de Sitter via the stochastic approach beyond slow roll
• Spectator dark matter in non-standard cosmologies