English

Ultra slow-roll inflation demystified

High Energy Physics - Phenomenology 2017-12-06 v3 Cosmology and Nongalactic Astrophysics High Energy Physics - Theory

Abstract

Ultra-slow-roll (USR) inflation is a new mode of inflation which corresponds to the occasions when the inflaton field must traverse an extremely flat part of the scalar potential, when the usual slow-roll (SR) fails. We investigate USR and obtain an estimate for how long it lasts, given the initial kinetic density of the inflaton. We also find that, if the initial kinetic density is small enough, USR can be avoided and the usual SR treatment is valid. This has important implications for inflection-point inflation.

Keywords

Cite

@article{arxiv.1707.05644,
  title  = {Ultra slow-roll inflation demystified},
  author = {Konstantinos Dimopoulos},
  journal= {arXiv preprint arXiv:1707.05644},
  year   = {2017}
}

Comments

10 pages, published version

R2 v1 2026-06-22T20:50:23.465Z