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Title: Inflationary dynamics with a smooth slow-roll to constant-roll era transition

Abstract

In this paper we investigate the implications of having a varying second slow-roll index on the canonical scalar field inflationary dynamics. We shall be interested in cases that the second slow-roll can take small values and correspondingly large values, for limiting cases of the function that quantifies the variation of the second slow-roll index. As we demonstrate, this can naturally introduce a smooth transition between slow-roll and constant-roll eras. We discuss the theoretical implications of the mechanism we introduce and we use various illustrative examples in order to better understand the new features that the varying second slow-roll index introduces. In the examples we will present, the second slow-roll index has exponential dependence on the scalar field, and in one of these cases, the slow-roll era corresponds to a type of α-attractor inflation. Finally, we briefly discuss how the combination of slow-roll and constant-roll may lead to non-Gaussianities in the primordial perturbations.

Authors:
 [1];  [2]
  1. ICREA, Passeig Luis Companys, 23, 08010 Barcelona (Spain)
  2. Laboratory for Theoretical Cosmology, Tomsk State University of Control Systems and Radioelectronics (TUSUR), Lenin Avenue 40, 634050 Tomsk (Russian Federation)
Publication Date:
OSTI Identifier:
22679897
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ATTRACTORS; DISTURBANCES; FIELD THEORIES; INFLATIONARY UNIVERSE; PERTURBATION THEORY; SCALAR FIELDS

Citation Formats

Odintsov, S.D., and Oikonomou, V.K., E-mail: odintsov@ieec.uab.es, E-mail: v.k.oikonomou1979@gmail.com. Inflationary dynamics with a smooth slow-roll to constant-roll era transition. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/04/041.
Odintsov, S.D., & Oikonomou, V.K., E-mail: odintsov@ieec.uab.es, E-mail: v.k.oikonomou1979@gmail.com. Inflationary dynamics with a smooth slow-roll to constant-roll era transition. United States. doi:10.1088/1475-7516/2017/04/041.
Odintsov, S.D., and Oikonomou, V.K., E-mail: odintsov@ieec.uab.es, E-mail: v.k.oikonomou1979@gmail.com. Sat . "Inflationary dynamics with a smooth slow-roll to constant-roll era transition". United States. doi:10.1088/1475-7516/2017/04/041.
@article{osti_22679897,
title = {Inflationary dynamics with a smooth slow-roll to constant-roll era transition},
author = {Odintsov, S.D. and Oikonomou, V.K., E-mail: odintsov@ieec.uab.es, E-mail: v.k.oikonomou1979@gmail.com},
abstractNote = {In this paper we investigate the implications of having a varying second slow-roll index on the canonical scalar field inflationary dynamics. We shall be interested in cases that the second slow-roll can take small values and correspondingly large values, for limiting cases of the function that quantifies the variation of the second slow-roll index. As we demonstrate, this can naturally introduce a smooth transition between slow-roll and constant-roll eras. We discuss the theoretical implications of the mechanism we introduce and we use various illustrative examples in order to better understand the new features that the varying second slow-roll index introduces. In the examples we will present, the second slow-roll index has exponential dependence on the scalar field, and in one of these cases, the slow-roll era corresponds to a type of α-attractor inflation. Finally, we briefly discuss how the combination of slow-roll and constant-roll may lead to non-Gaussianities in the primordial perturbations.},
doi = {10.1088/1475-7516/2017/04/041},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2017,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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