I Is Gravitational Red-Blue Shift Dismissed in Cosmic Observations?

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Gravitational redshift is a minor effect observed in the spectrum of the Sun, but it is not considered a significant factor in the redshift of distant galaxies. The prevailing explanation for the redshift of galaxies is the expansion of space, which accounts for over 99% of the observed redshift. While local galaxies like Andromeda experience blueshift due to gravitational attraction, distant galaxies are redshifted as their light travels vast distances through expanding space. The discussion emphasizes that the gravitational fields of galaxies are not strong enough to account for the observed redshift. Ultimately, the redshift of distant galaxies aligns well with current cosmological models.
trevorjobo83
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Why is gravitational red blue shift ruled out as a cause of what we see in stars and galaxy's and such?
 
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Can you be more specific about what you are asking? You can detect the gravitational redshift in the spectrum of the Sun, but it is a relatively small effect.
 
PeroK said:
:welcome:

Can you be more specific about what you are asking? You can detect the gravitational redshift in the spectrum of the Sun, but it is a relatively small effect.
Why do we think galaxy's exhibit red shift from velocity and not there tremendous gravity fields? The more distant galaxy's would have even more invisible gravity fields to travel through so gravity would red shift more the further the galaxy?
 
trevorjobo83 said:
Why do we think galaxy's exhibit red shift from velocity and not there tremendous gravity fields?
Because they don't have tremendous gravity fields. The galaxy dynamics of distant galaxies are the same as local galaxies.
 
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I'm thinking the blue shift of local galaxy's is because those galaxy's exist in the same gravity field of our universe, provided by a nucleus, and that distant galaxy's are all red because the light of those galaxy's travels away from the nucleus over there?
 
PeroK said:
Because they don't have tremendous gravity fields. The galaxy dynamics of distant galaxies are the same as local galaxies.
A galaxy with a zillion stars has less gravity then the sun which red shifts light?
 
trevorjobo83 said:
I'm thinking the blue shift of local galaxy's is because those galaxy's exist in the same gravity field of our universe, provided by a nucleus, and that distant galaxy's are all red because the light of those galaxy's travels away from the nucleus over there?
The rules of the forum preclude discussing your own personal theories.
 
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PeroK said:
The rules of the forum preclude discussing your own personal theories.
really? Einy came up with it. I just expanded.
 
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I'm thinking the red shift of the distant galaxy's being redder would blue shift as it enters our universal gravity field, or our galaxy's, or the sun's or earth's for that matter, but is so red shifted between here and there that the light remains red when it reaches us?
 
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trevorjobo83 said:
I'm thinking the red shift of the distant galaxy's being redder would blue shift as it enters our universal gravity field, or our galaxy's, or the sun's or earth's for that matter, but is so red shifted between here and there that the light remains red when it reaches us?
The gravitational redshift between even the surface of the Sun and infinity is tiny; cosmological redshifts are much, much larger.
 
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trevorjobo83 said:
I'm thinking the red shift of the distant galaxy's being redder would blue shift as it enters our universal gravity field, or our galaxy's, or the sun's or earth's for that matter, but is so red shifted between here and there that the light remains red when it reaches us?
Sort of? If I understand you correctly. The light is redshifted a very small amount just getting out from the star and a bit more getting out of its galaxy, as it is moving upwards in a gravity well and losing energy. Then it is redshifted a very large amount during its multi-billion year travel through intergalactic space. As it approaches our galaxy it is blueshifted a small amount, then a bit more as it moves downward into the Sun's and Earth's gravity well. By far the most dominant source of redshift is the expansion of space over the huge distances and time that the light travels between galaxies. For almost all galaxies the redshift from the expansion of space is more than 99% of the redshift.
 
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trevorjobo83 said:
I'm thinking the blue shift of local galaxy's is because those galaxy's exist in the same gravity field of our universe, provided by a nucleus, and that distant galaxy's are all red because the light of those galaxy's travels away from the nucleus over there?
No. Nearby galaxies, like the Andromeda galaxy, are close enough to be bound to us via gravity, which prevents the expansion of space from taking place between us. So light traveling between the Milky Way and Andromeda isn't redshifted hardly at all. In fact, it is blueshifted a small amount, as the two galaxies are moving towards each other.

Note that there is only one gravitational field. Objects just influence this field via their mass.
 
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trevorjobo83 said:
really? Einy came up with it. I just expanded.
And after your “just expanded” part is published in the professional scientific literature then it would be suitable for discussion here. Until then, this thread is closed.

For what it is worth, the redshift of distant galaxies is well explained by the current model.
 
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