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arXiv · 1712.09653

Dark energy, scalar singlet dark matter and the Higgs portal

Abstract

One of the simplest extensions of the Standard Model (SM) comprises the inclusion of a massive real scalar field, neutral under the SM gauge groups, to be a dark matter candidate. The addition of a dimension-six term into the potential of the scalar dark matter enables the appearance of a false vacuum that describes the cosmic acceleration. We show that the running of the singlet self-interaction and the Higgs portal coupling differs from the standard scalar singlet dark matter model. If we maintain a positive quartic coupling, it is also possible to describe the accelerated expansion of the Universe through a false vacuum with the addition of a dimension-eight interaction term. In this case, where the potential remains bounded from below at low energies, the false vacuum decay is highly suppressed.

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Ricardo G. Landim. 2018-05-16. Dark energy, scalar singlet dark matter and the Higgs portal. https://doi.org/10.1142/s0217732318500876

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