New answers tagged expansion
6
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Accepted
Why is the CMB's redshift so high?
Well during those periods we can assume universe is matter dominated. Thus, we can write $a(t) \propto t^{2/3}$. By also using $1+z = a^{-1}$, we can write.
$$\frac{1+z_{\rm CMB}}{1 + z_{\rm HD1}} = \...
- 556
1
vote
Why are galaxies thought to get bigger with distance in an expanding universe model?
It's actually due to the Angular Diameter distance. I still don't understand the exact mechanism, but I can shed some light on it. The angular diameter distance can be written as
$$d_A = \frac{\chi}{1+...
- 556
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