Nonperturbative Dynamics Of Reheating After Inflation: A Review

TL;DR

This review discusses the complex nonperturbative processes during reheating after inflation, highlighting recent theoretical and numerical advances, and exploring potential observational signatures of this crucial early universe phase.

Contribution

It provides a comprehensive overview of current understanding, models, and tools related to the nonlinear dynamics of reheating after inflation, emphasizing recent developments.

Findings

Reheating involves rich nonlinear dynamics with potential observational signatures.

Analytical and numerical tools are crucial for studying preheating and reheating.

Reheating successfully leads to a thermal universe before BBN.

Abstract

Our understanding of the state of the universe between the end of inflation and big bang nucleosynthesis (BBN) is incomplete. The dynamics at the end of inflation are rich and a potential source of observational signatures. Reheating, the energy transfer between the inflaton and Standard Model fields (possibly through intermediaries) and their subsequent thermalization, can provide clues to how inflation fits in with known high-energy physics. We provide an overview of our current understanding of the nonperturbative, nonlinear dynamics at the end of inflation, some salient features of realistic particle physics models of reheating, and how the universe reaches a thermal state before BBN. In addition, we review the analytical and numerical tools available in the literature to study preheating and reheating and discuss potential observational signatures from this fascinating era.