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Title: Stable solutions of inflation driven by vector fields

Abstract

Many models of inflation driven by vector fields alone have been known to be plagued by pathological behaviors, namely ghost and/or gradient instabilities. In this work, we seek a new class of vector-driven inflationary models that evade all of the mentioned instabilities. We build our analysis on the Generalized Proca Theory with an extension to three vector fields to realize isotropic expansion. We obtain the conditions required for quasi de-Sitter solutions to be an attractor analogous to the standard slow-roll one and those for their stability at the level of linearized perturbations. Identifying the remedy to the existing unstable models, we provide a simple example and explicitly show its stability. This significantly broadens our knowledge on vector inflationary scenarios, reviving potential phenomenological interests for this class of models.

Authors:
 [1];  [2];  [3];  [4]
  1. Institute for Advanced Study, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)
  2. Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto University, 606-8502, Kyoto (Japan)
  3. Department of Physics, McGill University, Montréal, QC, H3A 2T8 (Canada)
  4. National Astronomy Observatories, Chinese Academy of Science, Beijing 100012 (China)
Publication Date:
OSTI Identifier:
22679948
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DE SITTER SPACE; DISTURBANCES; EXPANSION; INFLATIONARY UNIVERSE; INSTABILITY; PERTURBATION THEORY; STABILITY; VECTOR FIELDS

Citation Formats

Emami, Razieh, Mukohyama, Shinji, Namba, Ryo, and Zhang, Ying-li, E-mail: iasraziehm@ust.hk, E-mail: shinji.mukohyama@yukawa.kyoto-u.ac.jp, E-mail: namba@physics.mcgill.ca, E-mail: yingli@bao.ac.cn. Stable solutions of inflation driven by vector fields. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/03/058.
Emami, Razieh, Mukohyama, Shinji, Namba, Ryo, & Zhang, Ying-li, E-mail: iasraziehm@ust.hk, E-mail: shinji.mukohyama@yukawa.kyoto-u.ac.jp, E-mail: namba@physics.mcgill.ca, E-mail: yingli@bao.ac.cn. Stable solutions of inflation driven by vector fields. United States. doi:10.1088/1475-7516/2017/03/058.
Emami, Razieh, Mukohyama, Shinji, Namba, Ryo, and Zhang, Ying-li, E-mail: iasraziehm@ust.hk, E-mail: shinji.mukohyama@yukawa.kyoto-u.ac.jp, E-mail: namba@physics.mcgill.ca, E-mail: yingli@bao.ac.cn. Wed . "Stable solutions of inflation driven by vector fields". United States. doi:10.1088/1475-7516/2017/03/058.
@article{osti_22679948,
title = {Stable solutions of inflation driven by vector fields},
author = {Emami, Razieh and Mukohyama, Shinji and Namba, Ryo and Zhang, Ying-li, E-mail: iasraziehm@ust.hk, E-mail: shinji.mukohyama@yukawa.kyoto-u.ac.jp, E-mail: namba@physics.mcgill.ca, E-mail: yingli@bao.ac.cn},
abstractNote = {Many models of inflation driven by vector fields alone have been known to be plagued by pathological behaviors, namely ghost and/or gradient instabilities. In this work, we seek a new class of vector-driven inflationary models that evade all of the mentioned instabilities. We build our analysis on the Generalized Proca Theory with an extension to three vector fields to realize isotropic expansion. We obtain the conditions required for quasi de-Sitter solutions to be an attractor analogous to the standard slow-roll one and those for their stability at the level of linearized perturbations. Identifying the remedy to the existing unstable models, we provide a simple example and explicitly show its stability. This significantly broadens our knowledge on vector inflationary scenarios, reviving potential phenomenological interests for this class of models.},
doi = {10.1088/1475-7516/2017/03/058},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2017,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}
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