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Friedmann equation

  1. Aug 20, 2006 #1
    Hi does anyone know a website or paper where the friedmann equation is derived from the robertson walker metric?
    it should have the calculation of atleast a few of the christoffel symbols etc


  2. jcsd
  3. Aug 20, 2006 #2
    The Friedmann equation can't be derived from the RW metric. It is a constraint on that metric, which is derived from the GR field equations. In other words, you can't derive it wityout the stress-energy tensor.
  4. Aug 20, 2006 #3
    You may be interested in reading Relativity Demystified by David McMahon. On page 161 the following problem is worked out: Consider the Robertson-Walker metric and suppose we take the Einstein equation with nonzero constant, find the Friedman equations.
  5. Aug 21, 2006 #4
    Hello Thank you for the reply
    So the friedmann equation is a constraint on the metric derived from the stress energy tensor
    what specific stress energy tensor is used? just the diagonal
    {-rho, p, p ,p }?
    also are theere any websites that have the derivation of this constraint equation from einsteins field equations>?
    i will also try to check out the book you recommended
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