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Cosmology: Proper distances

  • Thread starter Niles
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  • #1
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Homework Statement


Hi all.

When looking at a graph that shows the proper distance at the time of emission as a function of the redshift z in a model-universe with only matter, the proper distance at time of emission has a maximum at about z ~ 1.7. What does this maximum mean?

I can see that light with a high redshift must come from a source, which was initially close to us, and similarly light with a small redshift also comes from close to us. But again, what about the in-between, i.e. the maximum?
 

Answers and Replies

  • #2
Dick
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Since it's distance at the time of emission, yes, small z comes from sources nearby in distance and time and large z comes from sources that are currently far away, but were close at the time of emission because the universe was so much smaller. I think that's what you are saying. So, sure, then there must be a maximum. I don't think that maximum has any particular significance.
 
  • #3
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Ok, thanks. I didn't suspect it having any meaning, but it's always nice to get a second-opinion.
 

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