I The Acceleration and the density of galaxies

mbond
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In the Lambda-CDM model, the density of galaxies goes decreasing and should even vanish in the far future.

I would be grateful if someone could point me to a paper where this is calculated.
 
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It is a simple inference from the number of galaxies in a comoving volume staying constant while the size of the comoving volume increases. This just has to do with expansion itself, accelerated expansion is not required.
 
Also, as the universe expands, the density of galaxies decreases, but it never "vanishes".
 
I mean the number of visible galaxies goes vanishing because of the Acceleration. This is told in the book "A universe from nothing" by L.. Krauss, chapter "Our miserable future". Is there a paper or a reference where this is calculated?
 
mbond said:
I mean the number of visible galaxies goes vanishing because of the Acceleration. This is told in the book "A universe from nothing" by L.. Krauss, chapter "Our miserable future". Is there a paper or a reference where this is calculated?
This looks like a common misconception. Objects once seen never disappear. Apart from getting ever dimmer until eventually too hard to observe, that is. But the light is still there, reaching the observer.
Krauss has been guilty of wording this less-than-ideally in at least one other book - see e.g. this paper: https://arxiv.org/abs/astro-ph/0310808, example 13 in appendix B.
 
mbond said:
I mean the number of visible galaxies goes vanishing because of the Acceleration. This is told in the book "A universe from nothing" by L.. Krauss, chapter "Our miserable future". Is there a paper or a reference where this is calculated?
In addition to Bandersnatch's comment, nearby galaxies aren't moving apart. It isn't immediately obvious that they would ever necessarily spread out far enough to be part of the fading Bandersnatch mentions.
 
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