Gravity waves from nonminimal quadratic inflation
Abstract
We discuss nonminimal quadratic inflation in supersymmetric (SUSY) and nonSUSY models which entails a linear coupling of the inflaton to gravity. Imposing a lower bound on the parameter c{sub R}, involved in the coupling between the inflaton and the Ricci scalar curvature, inflation can be attained even for subplanckian values of the inflaton while the corresponding effective theory respects the perturbative unitarity up to the Planck scale. Working in the nonSUSY context we also consider radiative corrections to the inflationary potential due to a possible coupling of the inflaton to bosons or fermions. We find ranges of the parameters, depending mildly on the renormalization scale, with adjustable values of the spectral index n{sub s}, tensortoscalar ratio r≅(2−4)⋅ 10{sup −3}, and an inflaton mass close to 3⋅ 10{sup 13} GeV. In the SUSY framework we employ two gauge singlet chiral superfields, a logarithmic Kähler potential including all the allowed terms up to fourth order in powers of the various fields, and determine uniquely the superpotential by applying a continuous R and a global U(1) symmetry. When the Kähler manifold exhibits a noscaletype symmetry, the model predicts n{sub s} ≅ 0.963 and r≅ 0.004. Beyond noscale SUGRA, n{sub s} and r depend crucially on the coefficient involvedmore »
 Authors:
 Departament de Física Teòrica and IFIC, Universitat de ValènciaCSIC, E46100 Burjassot (Spain)
 Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)
 Publication Date:
 OSTI Identifier:
 22524859
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BOSONS; CHIRALITY; COSMOLOGICAL INFLATION; COUPLING; FERMIONS; GEV RANGE; GRAVITATION; GRAVITY WAVES; INFLATONS; MASS; POTENTIALS; RADIATIVE CORRECTIONS; RENORMALIZATION; SCALARS; SUPERSYMMETRY; TENSORS; U1 GROUPS; UNITARITY
Citation Formats
Pallis, Constantinos, and Shafi, Qaisar, Email: cpallis@ific.uv.es, Email: shafi@bartol.udel.edu. Gravity waves from nonminimal quadratic inflation. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/03/023.
Pallis, Constantinos, & Shafi, Qaisar, Email: cpallis@ific.uv.es, Email: shafi@bartol.udel.edu. Gravity waves from nonminimal quadratic inflation. United States. doi:10.1088/14757516/2015/03/023.
Pallis, Constantinos, and Shafi, Qaisar, Email: cpallis@ific.uv.es, Email: shafi@bartol.udel.edu. 2015.
"Gravity waves from nonminimal quadratic inflation". United States.
doi:10.1088/14757516/2015/03/023.
@article{osti_22524859,
title = {Gravity waves from nonminimal quadratic inflation},
author = {Pallis, Constantinos and Shafi, Qaisar, Email: cpallis@ific.uv.es, Email: shafi@bartol.udel.edu},
abstractNote = {We discuss nonminimal quadratic inflation in supersymmetric (SUSY) and nonSUSY models which entails a linear coupling of the inflaton to gravity. Imposing a lower bound on the parameter c{sub R}, involved in the coupling between the inflaton and the Ricci scalar curvature, inflation can be attained even for subplanckian values of the inflaton while the corresponding effective theory respects the perturbative unitarity up to the Planck scale. Working in the nonSUSY context we also consider radiative corrections to the inflationary potential due to a possible coupling of the inflaton to bosons or fermions. We find ranges of the parameters, depending mildly on the renormalization scale, with adjustable values of the spectral index n{sub s}, tensortoscalar ratio r≅(2−4)⋅ 10{sup −3}, and an inflaton mass close to 3⋅ 10{sup 13} GeV. In the SUSY framework we employ two gauge singlet chiral superfields, a logarithmic Kähler potential including all the allowed terms up to fourth order in powers of the various fields, and determine uniquely the superpotential by applying a continuous R and a global U(1) symmetry. When the Kähler manifold exhibits a noscaletype symmetry, the model predicts n{sub s} ≅ 0.963 and r≅ 0.004. Beyond noscale SUGRA, n{sub s} and r depend crucially on the coefficient involved in the fourth order term, which mixes the inflaton with the accompanying noninflaton field in the Kähler potential, and the prefactor encountered in it. Increasing slightly the latter above (−3), an efficient enhancement of the resulting r can be achieved putting it in the observable range. The inflaton mass in the last case is confined in the range (5−9)⋅ 10{sup 13} GeV.},
doi = {10.1088/14757516/2015/03/023},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2015,
place = {United States},
year = 2015,
month = 3
}

We discuss nonminimal quadratic inflation in supersymmetric (SUSY) and nonSUSY models which entails a linear coupling of the inflaton to gravity. Imposing a lower bound on the parameter c{sub R}, involved in the coupling between the inflaton and the Ricci scalar curvature, inflation can be attained even for subplanckian values of the inflaton while the corresponding effective theory respects the perturbative unitarity up to the Planck scale. Working in the nonSUSY context we also consider radiative corrections to the inflationary potential due to a possible coupling of the inflaton to bosons or fermions. We find ranges of the parameters, dependingmore »

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