Introduction to the number of $e$-folds in slow-roll inflation

Abstract

In this review, a pedagogical introduction to the concepts of slow-roll inflationary Universe and number of $e$-folds is provided. In particular, the differences between the basic notion of number of $e$-folds ($N_e$), total number of $e$-folds ($N_T$) and number of $e$-folds before the end of inflation ($N$), are outlined. The proper application of the number of $e$-folds before the end of inflation is discussed both as a time-like variable for the scalar field evolution and as a key parameter for computing inflationary predictions.

23 pages, Review for the Special Issue Universe: Feature Papers 2024 - 'Cosmology'

References in corpus (17)

• BICEP / Keck XIII: Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season
• Monodromy in the CMB: Gravity Waves and String Inflation
• Primordial Non-Gaussianities from Inflation Models
• Reheating in Inflationary Cosmology: Theory and Applications
• Nonperturbative Dynamics Of Reheating After Inflation: A Review
• Inflationary Cosmology
• The Unity of Cosmological Attractors
• The Powers of Monodromy
• Running Kinetic Inflation
• The Lyth Bound of Inflation with a Tilt
• On the dynamics of a quadratic scalar field potential
• Higgs Chaotic Inflation in Standard Model and NMSSM
• Inflating and Reheating the Universe with an Independent Affine Connection
• General Analysis of Inflation in the Jordan frame Supergravity
• Inflating an Inhomogeneous Universe
• Can CMB data constrain the inflationary field range?
• Lyth Bound, eternal inflation and future cosmological missions

Cited by in corpus (1)

• Quantum-Ordering Ambiguities in Weak Chern-Simons 4D Gravity and Metastability of the Condensate-Induced Inflation