Dark matter relic density in scalar-tensor gravity revisited

Journal Publication ResearchOnline@JCU
Meehan, Michael T.;Whittingham, Ian B.
Michael Meehan
Abstract

We revisit the calculation of dark matter relic abundances in scalar-tensor gravity using a generic form A(ϕ∗) = exp(βϕ∗2/2) for the coupling between the scalar field ϕ∗ and the metric, for which detailed Big Bang Nucleosynthesis constraints are available. We find that BBN constraints restrict the modified expansion rate in these models to be almost degenerate with the standard expansion history at the time of dark matter decoupling. In this case the maximum level of enhancement of the dark matter relic density was found to be a factor of ~ 3, several orders of magnitude below that found in previous investigations.

Journal

Journal of Cosmology and Astroparticle Physics

Publication Name

Journal of Cosmology and Astroparticle Physics

Volume

2015

ISBN/ISSN

1475-7516

Edition

N/A

Issue

12

Pages Count

29

Location

N/A

Publisher

Institute of Physics Publishing Ltd.

Publisher Url

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Publisher Location

N/A

Publish Date

N/A

Url

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Date

N/A

EISSN

N/A

DOI

10.1088/1475-7516/2015/12/011