Gravitational waves from axion monodromy
Abstract
Large field inflation is arguably the simplest and most natural variant of slowroll inflation. Axion monodromy may be the most promising framework for realising this scenario. As one of its defining features, the longrange polynomial potential possesses shortrange, instantonic modulations. These can give rise to a series of local minima in the postinflationary region of the potential. We show that for certain parameter choices the inflaton populates more than one of these vacua inside a single Hubble patch. This corresponds to a dynamical phase decomposition, analogously to what happens in the course of thermal firstorder phase transitions. In the subsequent process of bubble wall collisions, the lowestlying axionic minimum eventually takes over all space. Our main result is that this violent process sources gravitational waves, very much like in the case of a firstorder phase transition. We compute the energy density and peak frequency of the signal, which can lie anywhere in the mHzGHz range, possibly within reach of nextgeneration interferometers. We also note that this “dynamical phase decomposition' phenomenon and its gravitational wave signal are more general and may apply to other inflationary or reheating scenarios with axions and modulated potentials.
 Authors:

 Institute for Theoretical Physics, University of Heidelberg,Philosophenweg 19, 69120 Heidelberg (Germany)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22572175
 Resource Type:
 Journal Article
 Journal Name:
 Journal of Cosmology and Astroparticle Physics
 Additional Journal Information:
 Journal Volume: 2016; Journal Issue: 11; Other Information: PUBLISHERID: JCAP11(2016)003; OAI: oai:repo.scoap3.org:17880; ccby 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); Journal ID: ISSN 14757516
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AXIONS; COSMOLOGICAL INFLATION; ENERGY DENSITY; GRAVITATIONAL WAVES; INFLATIONARY UNIVERSE; INFLATONS; INSTANTONS; MHZ RANGE; PHASE TRANSFORMATIONS; POTENTIALS; STRING THEORY
Citation Formats
Hebecker, Arthur, Jaeckel, Joerg, Rompineve, Fabrizio, and Witkowski, Lukas T. Gravitational waves from axion monodromy. United States: N. p., 2016.
Web. doi:10.1088/14757516/2016/11/003.
Hebecker, Arthur, Jaeckel, Joerg, Rompineve, Fabrizio, & Witkowski, Lukas T. Gravitational waves from axion monodromy. United States. doi:10.1088/14757516/2016/11/003.
Hebecker, Arthur, Jaeckel, Joerg, Rompineve, Fabrizio, and Witkowski, Lukas T. Wed .
"Gravitational waves from axion monodromy". United States. doi:10.1088/14757516/2016/11/003.
@article{osti_22572175,
title = {Gravitational waves from axion monodromy},
author = {Hebecker, Arthur and Jaeckel, Joerg and Rompineve, Fabrizio and Witkowski, Lukas T.},
abstractNote = {Large field inflation is arguably the simplest and most natural variant of slowroll inflation. Axion monodromy may be the most promising framework for realising this scenario. As one of its defining features, the longrange polynomial potential possesses shortrange, instantonic modulations. These can give rise to a series of local minima in the postinflationary region of the potential. We show that for certain parameter choices the inflaton populates more than one of these vacua inside a single Hubble patch. This corresponds to a dynamical phase decomposition, analogously to what happens in the course of thermal firstorder phase transitions. In the subsequent process of bubble wall collisions, the lowestlying axionic minimum eventually takes over all space. Our main result is that this violent process sources gravitational waves, very much like in the case of a firstorder phase transition. We compute the energy density and peak frequency of the signal, which can lie anywhere in the mHzGHz range, possibly within reach of nextgeneration interferometers. We also note that this “dynamical phase decomposition' phenomenon and its gravitational wave signal are more general and may apply to other inflationary or reheating scenarios with axions and modulated potentials.},
doi = {10.1088/14757516/2016/11/003},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {14757516},
number = 11,
volume = 2016,
place = {United States},
year = {2016},
month = {11}
}