Interpreting hubble data

  • #1
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this graph: http://www.pnas.org/content/pnas/112/11/3173/F1.large.jpg?width=800&height=600&carousel=1
from: http://www.pnas.org/content/112/11/3173
can be found on many sites.
the origin is D=0 and t=0.
cosmology claims the universe is accelerating over time. the graph shows acceleration over distance, which is deceleration over time.
D = -Ct
andromeda's data shows it is 2.5 million light years away, so it is 2.5 million years old.
my engineering degree tells me that there is no dark energy nor a big bang.
 

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  • #2
Orodruin
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First of all, that plot is very old and currently only of historical value when it comes to understanding cosmology.

Second, it is only plotting quite nearby galaxies. You are never going to be able to distinguish an accelerating universe from a decelerating one with the data in that plot.

the origin is D=0 and t=0.
No it is not. You are misunderstanding the plot. The origin is D=0 and v = 0.

andromeda's data shows it is 2.5 million light years away, so it is 2.5 million years old.
This is just wrong and not a logical conclusion. The conclusion would be that the light you see from Andromeda now was emitted 2.5 million years ago. That does not mean that Andromeda did not exist before then. There is also a caveat to that and it is that in an expanding universe, the light travel-time vs distance does not work like that as space is expanding.

Furthermore, the local galaxy group (which both the Milky Way and Andromeda belong to) is gravitationally bound and therefore does not expand.

my engineering degree tells me that there is no dark energy nor a big bang.
Your engineering degree has then obviously not prepared you to understand how general relativity works.
 
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PeterDonis
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The OP is based on a misinterpretation, which has been corrected. Thread closed.
 

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