Cosmological tracking solutions

  title={Cosmological tracking solutions},
  author={Paul J. Steinhardt and Limin Wang and Ivaylo Zlatev},
  journal={Physical Review D},
A substantial fraction of the energy density of the universe may consist of quintessence in the form of a slowly rolling scalar field. Since the energy density of the scalar field generally decreases more slowly than the matter energy density, it appears that the ratio of the two densities must be set to a special, infinitesimal value in the early universe in order to have the two densities nearly coincide today. Recently, we introduced the notion of tracker fields to avoid this initial… Expand

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