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

@article{Krauss2003AgeEO,
title={Age Estimates of Globular Clusters in the Milky Way: Constraints on Cosmology},
author={Lawrence Krauss and Brian Chaboyer},
journal={Science},
year={2003},
volume={299},
pages={65 - 69}
}
• Published 3 January 2003
• Physics
• Science
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…
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