Alpher Bethe Gamow: Factor characterizing the decrease of density with time

AI Thread Summary
The discussion centers on the factor f(t), which characterizes the decrease of density over time in cosmology. Participants explore whether f(t) represents the density of the universe at a specific time and seek resources for further information. The Friedmann equation is suggested as a useful tool for deriving insights into density and time relationships. There is acknowledgment of the limitations of the Alpher-Bethe-Gamow model, particularly regarding non-Hydrogen and Helium elements. Overall, the conversation emphasizes the importance of understanding density dynamics in the context of cosmological models.
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Alpher Bethe Gamow: "Factor characterizing the decrease of density with time"

Directly from the article:

http://cache.artofproblemsolving.com/texer/images/c957650eca2c34559b5fd5931bd74440410d6ee3.png

where f(t) is a factor characterizing the decrease of the density with time.

What specifically is this f(t)? Is it just the density of the universe at time t? Where would this be available?

It seems to me that the Friedmann equation is a good place to derive this information, having both a term for density and time. However, I'm very new to cosmology.
 
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By the way, I know that αβγ is not a valid model for non-H/He elements, but I'm just carrying out the calculations myself.
 

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