The gravitational horizon for a Universe with phantom energy

  title={The gravitational horizon for a Universe with phantom energy},
  author={Fulvio Melia},
  journal={Journal of Cosmology and Astroparticle Physics},
  • F. Melia
  • Published 27 June 2012
  • Physics
  • Journal of Cosmology and Astroparticle Physics
The Universe has a gravitational horizon, coincident with the Hubble sphere, that plays an important role in how we interpret the cosmological data. Recently, however, its significance as a true horizon has been called into question, even for cosmologies with an equation-of-state w≡p/ρ ≥ −1, where p and ρ are the total pressure and energy density, respectively. The claim behind this argument is that its radius Rh does not constitute a limit to our observability when the Universe contains… 

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