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An Effective Cosmological Constant From an Entropic Formulation of Gravity

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 نشر من قبل Miguel Sabido
 تاريخ النشر 2018
  مجال البحث فيزياء
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We use the ideas of entropic gravity to derive the FRW cosmological model and show that for late time evolution we have an effective cosmological constant. By using the first law of thermodynamics and the modified entropy area relationship derived from the supersymmetric Wheeler-DeWitt equation of the Schwarzschild black hole, we obtain modifications to the Friedmann equations that in the late time regime gives an effective positive cosmological constant. Therefore, this simple model can account for the dark energy component of the universe by providing an entropic origin to the cosmological constant $Lambda$.

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