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Title: Plateau inflation from random non-minimal coupling

Abstract

A generic non-minimal coupling can push any higher-order terms of the scalar potential sufficiently far out in field space to yield observationally viable plateau inflation. We provide analytic and numerical evidence that this generically happens for a non-minimal coupling strength ξ of the order N{sub e}{sup 2}. In this regime, the non-minimally coupled field is sub-Planckian during inflation and is thus protected from most higher-order terms. For larger values of ξ, the inflationary predictions converge towards the sweet spot of PLANCK. The latter includes ξ≃10{sup 4} obtained from CMB normalization arguments, thus providing a natural explanation for the inflationary observables measured.

Authors:
 [1];  [2];  [3];  [2]
  1. Deutsches Elektronen-Synchrotron DESY, Theory Group,22603 Hamburg (Germany)
  2. Van Swinderen Institute for Particle Physics and Gravity, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands)
  3. (Belgium)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22572101
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 06; Other Information: PUBLISHER-ID: JCAP06(2016)036; OAI: oai:repo.scoap3.org:16087; cc-by Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COSMOLOGICAL INFLATION; COUPLING; INFLATIONARY UNIVERSE; POTENTIALS; RELICT RADIATION; SCALAR FIELDS

Citation Formats

Broy, Benedict J., Coone, Dries, Theoretische Natuurkunde,Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels, and Roest, Diederik. Plateau inflation from random non-minimal coupling. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/06/036.
Broy, Benedict J., Coone, Dries, Theoretische Natuurkunde,Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels, & Roest, Diederik. Plateau inflation from random non-minimal coupling. United States. doi:10.1088/1475-7516/2016/06/036.
Broy, Benedict J., Coone, Dries, Theoretische Natuurkunde,Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels, and Roest, Diederik. Mon . "Plateau inflation from random non-minimal coupling". United States. doi:10.1088/1475-7516/2016/06/036.
@article{osti_22572101,
title = {Plateau inflation from random non-minimal coupling},
author = {Broy, Benedict J. and Coone, Dries and Theoretische Natuurkunde,Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels and Roest, Diederik},
abstractNote = {A generic non-minimal coupling can push any higher-order terms of the scalar potential sufficiently far out in field space to yield observationally viable plateau inflation. We provide analytic and numerical evidence that this generically happens for a non-minimal coupling strength ξ of the order N{sub e}{sup 2}. In this regime, the non-minimally coupled field is sub-Planckian during inflation and is thus protected from most higher-order terms. For larger values of ξ, the inflationary predictions converge towards the sweet spot of PLANCK. The latter includes ξ≃10{sup 4} obtained from CMB normalization arguments, thus providing a natural explanation for the inflationary observables measured.},
doi = {10.1088/1475-7516/2016/06/036},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2016,
place = {United States},
year = {Mon Jun 20 00:00:00 EDT 2016},
month = {Mon Jun 20 00:00:00 EDT 2016}
}
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