How to avoid a swift kick in the chameleons

Recently, it was argued that the conformal coupling of the chameleon to matter fields created an issue for early universe cosmology. As standard model degrees of freedom become non-relativistic in the early universe, the chameleon is attracted towards a “surfing'' solution, so that it arri...

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Main Authors: Padilla, Antonio, Platts, Emma, Stefanyszyn, David, Walters, Anthony, Weltman, Amanda, Wilson, Toby
Format: Article
Published: IOP Publishing 2016
Subjects:
Online Access:https://eprints.nottingham.ac.uk/41011/
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author Padilla, Antonio
Platts, Emma
Stefanyszyn, David
Walters, Anthony
Weltman, Amanda
Wilson, Toby
author_facet Padilla, Antonio
Platts, Emma
Stefanyszyn, David
Walters, Anthony
Weltman, Amanda
Wilson, Toby
author_sort Padilla, Antonio
building Nottingham Research Data Repository
collection Online Access
description Recently, it was argued that the conformal coupling of the chameleon to matter fields created an issue for early universe cosmology. As standard model degrees of freedom become non-relativistic in the early universe, the chameleon is attracted towards a “surfing'' solution, so that it arrives at the potential minimum with too large a velocity. This leads to rapid variations in the chameleon's mass and excitation of high energy modes, casting doubts on the classical treatment at Big Bang Nucleosynthesis. Here we present the DBI chameleon, a consistent high energy modification of the chameleon theory that dynamically renders it weakly coupled to matter during the early universe thereby eliminating the adverse effects of the `kicks'. This is done without any fine tuning of the coupling between the chameleon and matter fields, and retains its screening ability in the solar system. We demonstrate this explicitly with a combination of analytic and numerical results.
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spelling nottingham-410112020-05-04T17:39:49Z https://eprints.nottingham.ac.uk/41011/ How to avoid a swift kick in the chameleons Padilla, Antonio Platts, Emma Stefanyszyn, David Walters, Anthony Weltman, Amanda Wilson, Toby Recently, it was argued that the conformal coupling of the chameleon to matter fields created an issue for early universe cosmology. As standard model degrees of freedom become non-relativistic in the early universe, the chameleon is attracted towards a “surfing'' solution, so that it arrives at the potential minimum with too large a velocity. This leads to rapid variations in the chameleon's mass and excitation of high energy modes, casting doubts on the classical treatment at Big Bang Nucleosynthesis. Here we present the DBI chameleon, a consistent high energy modification of the chameleon theory that dynamically renders it weakly coupled to matter during the early universe thereby eliminating the adverse effects of the `kicks'. This is done without any fine tuning of the coupling between the chameleon and matter fields, and retains its screening ability in the solar system. We demonstrate this explicitly with a combination of analytic and numerical results. IOP Publishing 2016-03-30 Article PeerReviewed Padilla, Antonio, Platts, Emma, Stefanyszyn, David, Walters, Anthony, Weltman, Amanda and Wilson, Toby (2016) How to avoid a swift kick in the chameleons. Journal of Cosmology and Astroparticle Physics, 2016 . 58/1-58/19. ISSN 1475-7516 Modified gravity Big bang nucleosynthesis Particle physics Cosmology connection http://iopscience.iop.org/article/10.1088/1475-7516/2016/03/058/meta doi:10.1088/1475-7516/2016/03/058 doi:10.1088/1475-7516/2016/03/058
spellingShingle Modified gravity
Big bang nucleosynthesis
Particle physics
Cosmology connection
Padilla, Antonio
Platts, Emma
Stefanyszyn, David
Walters, Anthony
Weltman, Amanda
Wilson, Toby
How to avoid a swift kick in the chameleons
title How to avoid a swift kick in the chameleons
title_full How to avoid a swift kick in the chameleons
title_fullStr How to avoid a swift kick in the chameleons
title_full_unstemmed How to avoid a swift kick in the chameleons
title_short How to avoid a swift kick in the chameleons
title_sort how to avoid a swift kick in the chameleons
topic Modified gravity
Big bang nucleosynthesis
Particle physics
Cosmology connection
url https://eprints.nottingham.ac.uk/41011/
https://eprints.nottingham.ac.uk/41011/
https://eprints.nottingham.ac.uk/41011/