Hello, I am reading this paper about quantum gravity, trying and failing to follow along in the derivation of this, eq (204) p. 72, expression for the scale factor:(adsbygoogle = window.adsbygoogle || []).push({});

[itex]

a(t) = a_1 \left( 1 + \frac 3 2 ( 1 + \omega ) H_1 (t - t_1) \right)^{\frac 2 {3(1+\omega)}}

[/itex]

(I'm not sure what the subscript 1 means, it's not clear from the text)

This we apparently can get from the equation

[itex]

3 H^2 - c^2 \Lambda = \frac{8 \pi G} {c^2} \rho

[/itex]

and

[itex]

\rho (t) = \rho_1 (\frac {a(t)} {a_1} )^{-3(1+\omega)}.

[/itex]

Could anyone help me with this?

/Rettaw

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# Deriving a scale factor expression for FLRW model

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