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Constraints from High Redshift Supernovae upon Scalar Field Cosmologies

Joshua A. Frieman·Ioav Waga
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Abstract

Recent observations of high-redshift Type Ia supernovae have placed stringent constraints on the cosmological constant $Λ$. We explore the implications of these SNe observations for cosmological models in which a classically evolving scalar field currently dominates the energy density of the Universe. Such models have been shown to share the advantages of $Λ$ models: compatibility with the spatial flatness predicted inflation; a Universe older than the standard Einstein-de Sitter model; and, combined with cold dark matter, predictions for large-scale structure formation in good agreement with data from galaxy surveys. Compared to the cosmological constant, these scalar field models are consistent with the SNe observations for a lower matter density, $Ω_{m0} \sim 0.2$, and a higher age, $H_0 t_0 \gtrsim 1$. Combined with the fact that scalar field models imprint a distinctive signature on the cosmic microwave background anisotropy, they remain currently viable and should be testable in the near future.

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Joshua A. Frieman, Ioav Waga. 1997-09-08. Constraints from High Redshift Supernovae upon Scalar Field Cosmologies. https://doi.org/10.1103/physrevd.57.4642

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