Can substitution solve the de sitter universe problem?

Thread starter p.p
Start date Jan 1, 2010
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Universe

Jan 1, 2010

p.p

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

P

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Jan 1, 2010

phsopher

Use a substitution

\frac{\Lambda R^2}{3} = \cosh^2\phi

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