Inflationary dynamics with a smooth slowroll to constantroll era transition
Abstract
In this paper we investigate the implications of having a varying second slowroll index on the canonical scalar field inflationary dynamics. We shall be interested in cases that the second slowroll can take small values and correspondingly large values, for limiting cases of the function that quantifies the variation of the second slowroll index. As we demonstrate, this can naturally introduce a smooth transition between slowroll and constantroll 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 slowroll index introduces. In the examples we will present, the second slowroll index has exponential dependence on the scalar field, and in one of these cases, the slowroll era corresponds to a type of αattractor inflation. Finally, we briefly discuss how the combination of slowroll and constantroll may lead to nonGaussianities in the primordial perturbations.
 Authors:
 ICREA, Passeig Luis Companys, 23, 08010 Barcelona (Spain)
 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., Email: odintsov@ieec.uab.es, Email: v.k.oikonomou1979@gmail.com. Inflationary dynamics with a smooth slowroll to constantroll era transition. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/04/041.
Odintsov, S.D., & Oikonomou, V.K., Email: odintsov@ieec.uab.es, Email: v.k.oikonomou1979@gmail.com. Inflationary dynamics with a smooth slowroll to constantroll era transition. United States. doi:10.1088/14757516/2017/04/041.
Odintsov, S.D., and Oikonomou, V.K., Email: odintsov@ieec.uab.es, Email: v.k.oikonomou1979@gmail.com. Sat .
"Inflationary dynamics with a smooth slowroll to constantroll era transition". United States.
doi:10.1088/14757516/2017/04/041.
@article{osti_22679897,
title = {Inflationary dynamics with a smooth slowroll to constantroll era transition},
author = {Odintsov, S.D. and Oikonomou, V.K., Email: odintsov@ieec.uab.es, Email: v.k.oikonomou1979@gmail.com},
abstractNote = {In this paper we investigate the implications of having a varying second slowroll index on the canonical scalar field inflationary dynamics. We shall be interested in cases that the second slowroll can take small values and correspondingly large values, for limiting cases of the function that quantifies the variation of the second slowroll index. As we demonstrate, this can naturally introduce a smooth transition between slowroll and constantroll 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 slowroll index introduces. In the examples we will present, the second slowroll index has exponential dependence on the scalar field, and in one of these cases, the slowroll era corresponds to a type of αattractor inflation. Finally, we briefly discuss how the combination of slowroll and constantroll may lead to nonGaussianities in the primordial perturbations.},
doi = {10.1088/14757516/2017/04/041},
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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