Re: Galaxies don't fly apart because their entire frame is rotating

Am Donnerstag000011, 11.04.2024 um 13:08 schrieb Python:

Le 11/04/2024 à 10:51, Thomas Heger a écrit :

Am 10.04.2024 um 15:30 schrieb J. J. Lodder:
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Also, perhaps our current state of the art technology wrt observing the
universe from our little earth is damn near pre embryonic wrt the grand
scheme of things... ;^)
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Usual observations from our perspective of the universe would require to
remove the effects of the delay, which is caused by the finite speed of
light.
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But this is not done.

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Of course it is done!!!
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You have definitely never read any paper about astronomy, or the history
of astronomy. As a matter of fact one of the main issue in astronomy is
to determine the distance of objects as precisely as possible.
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Thomas, why are you constantly making up stuff of that kind? Is it malice
or stupidity?
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Both?

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Hanlon's razor applies, I think.
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And for amusement: noting different delays of quasar fluctuations,
in passing through an Einstein lens, is a practical way
of establishing their cosmological distance,

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Sure, the delay is known.
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But how would you remove it?
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The difference in time is actually HUGE, hence you would need to wait a VERY long time, if you want to know the present position of stars seen a few billion light years away.

 *facepalm*
 Q. How to know what week day and month day will tomorrow be ?
A. Wait 24 hours, then look at your phone

You should hit a little harder, because it's not just weaks nor even years you need to wait.
To measure the position of a star in one billion light years distance you need to wait a billion years, before you can actually see the light emitted from that star.
Because that is impossible, we simply don't know to were those stars went in the meantime.
We know that stars move around in the universe, but cannot tell, to were they went in the unobserved time of the last billion years.
It is therefore entirely pointless to figure out gravity between forground and background stars.
It may evetually be possible, to make plausible predictions about their future fate. But to do so, we would need to know, what cosmologists actually try to figure out: the influence of gravity by other objects.

 

In the meantime cosmologists explain the positions of stars, which do not belong to the same time.

 In the meantime cosmologists are not idiots, they know about physics (while you do not).

Well, they are certainly smart enough to stay in they job.
TH