Weinberg's Cosmology: Neglecting (1+z(eq)) in Denominator

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The discussion centers on the equation from Weinberg's "Cosmology," specifically why the term "(1+z(eq))" is considered negligible in the denominator alongside "R₁⁴." Participants suggest that this is due to the assumption that the redshift z is very close to 0, simplifying the equation. There is a request for the specific page number in Weinberg's book for context, as some users prefer not to search through the text manually. The conversation highlights the importance of understanding the implications of redshift in cosmological equations. Overall, the focus is on clarifying the mathematical reasoning behind Weinberg's approach.
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In equation below
〖H₁〗^2/〖H₀〗^2 =Ω₀(cri) (R₀⁴)/(R₁⁴(1+z(eq)))

Why is the term “(1+z(eq))” negligible in denominator according to the term “ R₁⁴ ” ?

Weinburg did it in his book named "Cosmology".
 
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I would assume that z is incredibly close to 0.
 
EhsanZ said:
Weinburg did it in his book named "Cosmology".

I would like to see the context, but I don't feel like looking for this by flipping through Weinberg page-by-page. Could you please give the page number?
 

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