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Homework Help: De sitter universe problem

  1. Jan 1, 2010 #1


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    rho=0, lambda>0 and k=1 with the initial condition R(0) = sqrt(3/lambda), the solution is
    R(t) = sqrt(3/lambda)cosh*(sqrt(lambda/3)*ct)

    This the the de sitter universe, however i am having problems finding a way around how to solve it from the Friedmann equation:

    dR/sqrt((lambda*R^2/3)-1) = ct

  2. jcsd
  3. Jan 1, 2010 #2
    Use a substitution

    [tex]\frac{\Lambda R^2}{3} = \cosh^2\phi[/tex]
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