Infrared Behavior of Quantum Fields in Inflationary Cosmology -- Issues and Approaches: an overview

Abstract

This is a pedagogical guide to works on this subject which began in the 80s but has seen vibrant activities in the last decade. It aims to help orient readers, especially students, who wish to enter into research but bewildered by the vast and diverse literature on this subject. We describe the three main veins of activities: the Euclidean zero-mode dominance, the Lorentzian interacting quantum field theory and the classical stochastic field theory approaches in some detail, explaining the underlying physics and the technicalities of each. We show how these approaches are interconnected, and highlight recent papers which contain germs of worthy directions for future developments.

arXiv comment56 pages, a chapter in the forthcoming book "Semiclassical and Stochastic Gravity -- Quantum Field Effects on Curved Spacetime" by Bei-Lok B. Hu and Enric Verdaguer, Cambridge University Press 2019. arXiv admin note: text overlap with arXiv:1807.05964, arXiv:1506.06183, arXiv:1412.4893, arXiv:1808.00338, arXiv:1603.07338, arXiv:1402.2076, arXiv:1310.0367, arXiv:1212.3058, arXiv:0807.5006, arXiv:1205.3097 by other authors

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Cited by in corpus (7)

• Bootstrapping Multi-Field Inflation: non-Gaussianities from light scalars revisited
• Stochastic Inflation at NNLO
• The Asymptotic Structure of Cosmological Integrals
• Massless minimal quantum scalar field with an asymmetric self interaction in de Sitter spacetime
• Cosmological Infrared Subtractions & Infrared-Safe Computables
• Quantum backreaction of $O(N)$-symmetric scalar fields and de Sitter spacetimes at the renormalization point: renormalization schemes and the screening of the cosmological constant
• Gravitational fermion creation during an anisotropic phase of cosmological expansion