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Observation of Cosmic Acceleration and Determining the Fate of the Universe

Glenn Starkman·Mark Trodden·Tanmay Vachaspati
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Abstract

Current observations of Type Ia supernovae provide evidence for cosmic acceleration out to a redshift of $z \lsim 1$, leading to the possibility that the universe is entering an inflationary epoch. However, inflation can take place only if vacuum-energy (or other sufficiently slowly redshifting source of energy density) dominates the energy density of a region of physical radius 1/H. We argue that for the best-fit values of $Ω_Λ$ and $Ω_m$ inferred from the supernovae data, one must confirm cosmic acceleration out to at least $z \simeq 1.8$ to infer that the universe is inflating.

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Glenn Starkman, Mark Trodden, Tanmay Vachaspati. 1999-12-07. Observation of Cosmic Acceleration and Determining the Fate of the Universe. https://doi.org/10.1103/physrevlett.83.1510

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