Gauss–Bonnet cosmologies: crossing the phantom divide and the transition from matter dominance to dark energy

  title={Gauss–Bonnet cosmologies: crossing the phantom divide and the transition from matter dominance to dark energy},
  author={Ben M. Leith and Ishwaree P. Neupane},
  journal={Journal of Cosmology and Astroparticle Physics},
  pages={019 - 019}
  • B. LeithI. Neupane
  • Published 1 February 2007
  • Physics
  • Journal of Cosmology and Astroparticle Physics
Dark energy cosmologies with an equation of state parameter w less than −1 are often found to violate the null energy condition and show unstable behaviour. A solution to this problem may require the existence of a consistent effective theory that violates the null energy condition only momentarily and does not develop any instabilities or other pathological features for a late time cosmology. A model which incorporates a dynamical scalar field φ coupled to the quadratic Riemann invariant of… 

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