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Title: Preheating and entropy perturbations in axion monodromy inflation

Abstract

We study the preheating of gauge fields in a simple axion monodromy model and compute the induced entropy perturbations and their effect on the curvature fluctuations. We find that the correction to the spectrum of curvature perturbations has a blue spectrum with index n{sub s}=5/2. Hence, these induced modes are harmless for the observed structure of the universe. Since the spectrum is blue, there is the danger of overproduction of primordial black holes. However, we show that the observational constraints are easily satisfied.

Authors:
;  [1];  [1];  [2]
  1. Department of Physics, McGill University,Montréal, QC H3A 2T8 (Canada)
  2. (Switzerland)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22572073
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 05; Other Information: PUBLISHER-ID: JCAP05(2016)012; OAI: oai:repo.scoap3.org:15477; 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; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AXIONS; BLACK HOLES; DISTURBANCES; ENTROPY; GAUGE INVARIANCE; INFLATIONARY UNIVERSE; PERTURBATION THEORY; STRING THEORY; UNIVERSE

Citation Formats

McDonough, Evan, Moghaddam, Hossein Bazrafshan, Brandenberger, Robert H., and Institute for Theoretical Studies, ETH Zürich,CH-8092 Zürich. Preheating and entropy perturbations in axion monodromy inflation. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/05/012.
McDonough, Evan, Moghaddam, Hossein Bazrafshan, Brandenberger, Robert H., & Institute for Theoretical Studies, ETH Zürich,CH-8092 Zürich. Preheating and entropy perturbations in axion monodromy inflation. United States. doi:10.1088/1475-7516/2016/05/012.
McDonough, Evan, Moghaddam, Hossein Bazrafshan, Brandenberger, Robert H., and Institute for Theoretical Studies, ETH Zürich,CH-8092 Zürich. 2016. "Preheating and entropy perturbations in axion monodromy inflation". United States. doi:10.1088/1475-7516/2016/05/012.
@article{osti_22572073,
title = {Preheating and entropy perturbations in axion monodromy inflation},
author = {McDonough, Evan and Moghaddam, Hossein Bazrafshan and Brandenberger, Robert H. and Institute for Theoretical Studies, ETH Zürich,CH-8092 Zürich},
abstractNote = {We study the preheating of gauge fields in a simple axion monodromy model and compute the induced entropy perturbations and their effect on the curvature fluctuations. We find that the correction to the spectrum of curvature perturbations has a blue spectrum with index n{sub s}=5/2. Hence, these induced modes are harmless for the observed structure of the universe. Since the spectrum is blue, there is the danger of overproduction of primordial black holes. However, we show that the observational constraints are easily satisfied.},
doi = {10.1088/1475-7516/2016/05/012},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2016,
place = {United States},
year = 2016,
month = 5
}
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