Ghosts in the self-accelerating universe

  title={Ghosts in the self-accelerating universe},
  author={Kazuya Koyama},
  journal={Classical and Quantum Gravity},
  • K. Koyama
  • Published 15 September 2007
  • Physics
  • Classical and Quantum Gravity
The self-accelerating universe realizes the accelerated expansion of the universe at late times by large-distance modification of general relativity (GR) without a cosmological constant. The Dvali–Gabadadze–Porrati (DGP) braneworld model provides an explicit example of the self-accelerating universe. Recently, the DGP model became very popular for studying the observational consequences of the modified gravity models as an alternative to dark energy models in GR. However, it has been shown that… 

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