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Title: Large tensor mode, field range bound and consistency in generalized G-inflation

Abstract

We systematically show that in potential driven generalized G-inflation models, quantum corrections coming from new physics at the strong coupling scale can be avoided, while producing observable tensor modes. The effective action can be approximated by the tree level action, and as a result, these models are internally consistent, despite the fact that we introduced new mass scales below the energy scale of inflation. Although observable tensor modes are produced with sub-strong coupling scale field excursions, this is not an evasion of the Lyth bound, since the models include higher-derivative non-canonical kinetic terms, and effective rescaling of the field would result in super-Planckian field excursions. We argue that the enhanced kinetic term of the inflaton screens the interactions with other fields, keeping the system weakly coupled during inflation.

Authors:
; ; ;  [1]
  1. Research Center for the Early Universe, Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan)
Publication Date:
OSTI Identifier:
22525534
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 08; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACTION INTEGRAL; APPROXIMATIONS; CORRECTIONS; COSMOLOGICAL INFLATION; INFLATIONARY UNIVERSE; INFLATONS; MASS; POTENTIALS; SCREENS; STRONG-COUPLING MODEL; TENSORS

Citation Formats

Kunimitsu, Taro, Suyama, Teruaki, Watanabe, Yuki, and Yokoyama, Jun'ichi, E-mail: kunimitsu@resceu.s.u-tokyo.ac.jp, E-mail: suyama@resceu.s.u-tokyo.ac.jp, E-mail: watanabe@resceu.s.u-tokyo.ac.jp, E-mail: yokoyama@resceu.s.u-tokyo.ac.jp. Large tensor mode, field range bound and consistency in generalized G-inflation. United States: N. p., 2015. Web. doi:10.1088/1475-7516/2015/08/044.
Kunimitsu, Taro, Suyama, Teruaki, Watanabe, Yuki, & Yokoyama, Jun'ichi, E-mail: kunimitsu@resceu.s.u-tokyo.ac.jp, E-mail: suyama@resceu.s.u-tokyo.ac.jp, E-mail: watanabe@resceu.s.u-tokyo.ac.jp, E-mail: yokoyama@resceu.s.u-tokyo.ac.jp. Large tensor mode, field range bound and consistency in generalized G-inflation. United States. doi:10.1088/1475-7516/2015/08/044.
Kunimitsu, Taro, Suyama, Teruaki, Watanabe, Yuki, and Yokoyama, Jun'ichi, E-mail: kunimitsu@resceu.s.u-tokyo.ac.jp, E-mail: suyama@resceu.s.u-tokyo.ac.jp, E-mail: watanabe@resceu.s.u-tokyo.ac.jp, E-mail: yokoyama@resceu.s.u-tokyo.ac.jp. 2015. "Large tensor mode, field range bound and consistency in generalized G-inflation". United States. doi:10.1088/1475-7516/2015/08/044.
@article{osti_22525534,
title = {Large tensor mode, field range bound and consistency in generalized G-inflation},
author = {Kunimitsu, Taro and Suyama, Teruaki and Watanabe, Yuki and Yokoyama, Jun'ichi, E-mail: kunimitsu@resceu.s.u-tokyo.ac.jp, E-mail: suyama@resceu.s.u-tokyo.ac.jp, E-mail: watanabe@resceu.s.u-tokyo.ac.jp, E-mail: yokoyama@resceu.s.u-tokyo.ac.jp},
abstractNote = {We systematically show that in potential driven generalized G-inflation models, quantum corrections coming from new physics at the strong coupling scale can be avoided, while producing observable tensor modes. The effective action can be approximated by the tree level action, and as a result, these models are internally consistent, despite the fact that we introduced new mass scales below the energy scale of inflation. Although observable tensor modes are produced with sub-strong coupling scale field excursions, this is not an evasion of the Lyth bound, since the models include higher-derivative non-canonical kinetic terms, and effective rescaling of the field would result in super-Planckian field excursions. We argue that the enhanced kinetic term of the inflaton screens the interactions with other fields, keeping the system weakly coupled during inflation.},
doi = {10.1088/1475-7516/2015/08/044},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 08,
volume = 2015,
place = {United States},
year = 2015,
month = 8
}
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