Dark energy and the Hubble age

Lawrence Krauss

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

I point out that an effective upper limit of approximately 20(0.2/ωm)1/2 Gyr (for a Hubble constant of 72 km s-1 Mpc-1), or alternatively, 1.49(0. 2/ωm)1/2 for the H0-independent quantity H0t0, exists on the age of the universe, essentially independent of the unknown equation of state of the dominant dark energy component in the universe. If astrophysical constraints on the age of the universe can convincingly reduce the upper limit to well below this value, a useful lower limit on the equation of state parameter w for this component can be obtained. Direct dating by stars does not provide a useful constraint, but model-dependent cosmological limits from supernovae and the CMB observations can do so.

Original languageEnglish (US)
Pages (from-to)481-483
Number of pages3
JournalAstrophysical Journal
Volume604
Issue number2 I
DOIs
StatePublished - Apr 1 2004
Externally publishedYes

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dark energy
equation of state
universe
energy
equations of state
Hubble constant
dating
supernovae
astrophysics
stars
parameter

Keywords

  • Cosmological parameters
  • Cosmology: theory
  • Equation of state
  • Galaxy: fundamental parameters
  • Gravitation

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Dark energy and the Hubble age. / Krauss, Lawrence.

In: Astrophysical Journal, Vol. 604, No. 2 I, 01.04.2004, p. 481-483.

Research output: Contribution to journalArticle

Krauss, L 2004, 'Dark energy and the Hubble age', Astrophysical Journal, vol. 604, no. 2 I, pp. 481-483. https://doi.org/10.1086/382121
Krauss, Lawrence. / Dark energy and the Hubble age. In: Astrophysical Journal. 2004 ; Vol. 604, No. 2 I. pp. 481-483.
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