(i) Obtain the scale factor a(t) and redshift z when the energy density of matter and radiation were equal.(adsbygoogle = window.adsbygoogle || []).push({});

(ii) Next use the a(t) relation for a matter-only universe to estimate the time of matter-radiation equality.

(iii) Repeat (ii) but using the a(t) relation for a radiation-only universe. Which approximation, (ii) or (iii), is closer to the correct answer?

Can someone help me?

Thanks!!

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# Scalefactor calculations for special cases using the Friedmann Equation

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