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arXiv · 1104.1349

Vacuum fluctuations in a supersymmetric model in FRW spacetime

Neven Bilic
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Abstract

We study a noninteracting supersymmetric model in an expanding FRW spacetime. A soft supersymmetry breaking induces a nonzero contribution to the vacuum energy density. A short distance cutoff of the order of Planck length provides a scale for the vacuum energy density comparable with the observed cosmological constant. Assuming the presence of a dark energy substance in addition to the vacuum fluctuations of the field an effective equation of state is derived in a selfconsistent approach. The effective equation of state is sensitive to the choice of the cut-off but no fine tuning is needed.

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Neven Bilic. 2011-04-07. Vacuum fluctuations in a supersymmetric model in FRW spacetime. https://doi.org/10.1103/physrevd.83.105003

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