Age Estimates of Globular Clusters in the Milky Way: Constraints on Cosmology

  title={Age Estimates of Globular Clusters in the Milky Way: Constraints on Cosmology},
  author={Lawrence Krauss and Brian Chaboyer},
  pages={65 - 69}
Recent observations of stellar globular clusters in the Milky Way Galaxy, combined with revised ranges of parameters in stellar evolution codes and new estimates of the earliest epoch of globular cluster formation, result in a 95% confidence level lower limit on the age of the Universe of 11.2 billion years. This age is inconsistent with the expansion age for a flat Universe for the currently allowed range of the Hubble constant, unless the cosmic equation of state is dominated by a component… 
Distances and ages of globular clusters
  • B. Chaboyer
  • Physics
    Proceedings of the International Astronomical Union
  • 2007
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