How to calculate the age of the universe with redshift

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To calculate the age of the universe at a specific redshift, the scale factor must first be determined using the formula R(t) = 1/(1+z). For a flat universe, the lookback time (t_L) can be calculated with the equation t_L = t_H * (2/3) * (1 - (1+z)^(-3/2)), where t_H is the Hubble time, approximately 13.8 billion years. At a redshift of 0.6, the lookback time is approximately 0.337 times the Hubble time. This method provides a straightforward approach to solving the problem, and relevant formulas should be available in cosmology course materials. Understanding these calculations is essential for determining the universe's age at different redshifts.
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Hi i am confused as to how to calculate the age of the universe with redshift
say for example

The age of the universe now is 13.4 billion years old (and a critical universe).
How do i find the age of the universe if it was a redshift at say 0.6??

Do i have to find the scale factor first?
I am not very sure, please help!
 
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someone help me with it please
 
The scale factor is related to the red shift.

R(t) = 1/(1+z) ; where R(t) is the scale factor at time t. R(t_0) = 1, t-0 is today.

What we want is the "lookback time" (t_L)

For a flat Universe, this is:

t_L = t_H * (2/3) * (1 - (1+z)^(-3/2))

t_H is the Hubble time ( 1 /H_0 ); approx 13.8 Gyr.
H_0 is the Hubble constant.

t_L = 0.337 t_H

I don't know what values you have in your book and so on, but this one way to solve it, there is probably more. The way to deduce the forumulas is pretty straightforward, it should be stated in our course book in cosmolgy.
 

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