Everpresent Lambda

  title={Everpresent Lambda},
  author={Maqbool Ahmed and Scott Dodelson and Patrick B. Greene and Rafael Sorkin},
A variety of observations indicate that the universe is dominated by dark energy with negative pressure, one possibility for which is a cosmological constant. If the dark energy is a cosmological constant, a fundamental question is: Why has it become relevant at so late an epoch, making today the only time in the history of the universe at which the cosmological constant is of order the ambient density. We explore an answer to this question drawing on ideas from unimodular gravity, which… 

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Implications of a cosmological constant varying as R-2.

  • ChenWu
  • Physics
    Physical review. D, Particles and fields
  • 1990
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