Is Gravitational Red-Blue Shift Dismissed in Cosmic Observations?

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Discussion Overview

The discussion revolves around the gravitational redshift and its potential role in explaining the observed redshift of distant galaxies, contrasting it with the redshift attributed to the expansion of the universe. Participants explore the implications of gravitational fields on light from galaxies and question the prevailing interpretations of redshift phenomena.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants question why gravitational redshift is not considered a significant factor in the observed redshift of galaxies, suggesting that distant galaxies might experience more substantial gravitational effects.
  • Others argue that the dynamics of distant galaxies do not exhibit tremendous gravitational fields compared to local galaxies, implying that velocity is a more relevant factor for redshift.
  • One participant proposes that local galaxies might be blue-shifted due to their proximity to a central gravitational influence, while distant galaxies are red-shifted as their light travels away from this influence.
  • Another participant suggests that light from distant galaxies experiences a small redshift due to gravitational effects when escaping their galaxies, but the dominant factor is the cosmological redshift from the expansion of space over vast distances.
  • There is a contention regarding the interpretation of gravitational fields, with some asserting that there is only one gravitational field influenced by mass, while others seem to imply multiple fields based on galaxy dynamics.

Areas of Agreement / Disagreement

Participants express differing views on the significance of gravitational redshift versus cosmological redshift, indicating that multiple competing perspectives remain unresolved in the discussion.

Contextual Notes

Some participants reference the small magnitude of gravitational redshift compared to cosmological redshift, but the discussion does not resolve the implications of these observations or the definitions of gravitational fields in this context.

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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: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.
 
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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  • #10
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.
 
  • #11
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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  • #12
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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