how do you calculate the redshift at which the universe shifted from radiation dominated to mass dominated(adsbygoogle = window.adsbygoogle || []).push({});

i was told to assume a flat universe with H0 = 70

also the temperature, to which i was given the formula density rad = aT^4

for the first part, i tried using density is propotional to scale factor ^3 and ^4

but it's not working too hot :(

help please, i need it done by tonight :(

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# Calculating the redshift at which radiation energy density equaled mass density

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