Redshift - does energy fade or get absorbed?

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    Energy Redshift
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Discussion Overview

The discussion revolves around the nature of redshift and its implications for understanding the expansion of the universe. Participants explore whether redshift is solely due to the universe's expansion or if it could be influenced by other factors, such as light absorption or scattering by particles over vast distances.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • One participant questions if redshift might be attributed to light energy fading or being absorbed by particles in space, rather than the universe's expansion.
  • Another participant asserts that redshift is not the only evidence for the universe's expansion, referencing Einstein's work on relativity and the historical context of its acceptance.
  • A participant mentions the "tired light" theory, suggesting it has been falsified based on calculations that do not align with observed data.
  • Concerns are raised about the effects of minuscule particles on light, with a participant noting that while these effects can be observed, they are difficult to quantify in terms of redshift.
  • One participant explains that redshift is related to energy conservation in an expanding universe, suggesting that it plays a crucial role in maintaining thermodynamic laws.

Areas of Agreement / Disagreement

Participants express differing views on the causes of redshift, with some supporting the traditional interpretation linked to cosmic expansion and others proposing alternative explanations. The discussion remains unresolved, with multiple competing views present.

Contextual Notes

Participants highlight the complexity of factors influencing light as it travels through space, including potential absorption and scattering by particles, which complicates the understanding of redshift.

Corkie2003
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Is it possible that redshift, though correct in it's theory, is not what we are viewing in terms of expansion of the universe?

Is it possible that what we think is redshift is actually the strength of the light/energy fading, being absorbed or blocked over hundreds of millions of light years?

I ask this because it seems to me that in the vast chasms of space between the observer and the observed, there have to be a large number of free-roaming particles of dust that would diminish the light, if only by a minescule amount at a time. Thus the light becomes dimmer, or darker.

Is there any possibility that the universe is not actually expanding like we think it is based on the Redshift theory?

Help me please because I'm a bit thick.
 
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The redshift is not the only reason that we know the universe is expanding. When Albert Einstein worked out Relativity and predicted how gravity works his calcultions indicated that the universe must be expanding, he didn't believe it was and so adjusted his calculations to compensate. It was Hubbard who convinced him that the universe really was expanding that his calculations were correct.
 
Corkie2003 said:
Is it possible that what we think is redshift is actually the strength of the light/energy fading, being absorbed or blocked over hundreds of millions of light years?

Tzemach is right. In addition you can actually calculate the results of this "tired light" theory, and those calulations don't agree with the observed numbers. So that theory has been falsified. So goes science, then we try another theory.
 
selfAdjoint said:
Tzemach is right. In addition you can actually calculate the results of this "tired light" theory, and those calulations don't agree with the observed numbers. So that theory has been falsified. So goes science, then we try another theory.


Nuff said, thanks for your help folks.

I go away slightly less in the dark than when I arrived.

:rolleyes:

What about the effect of miniscule particles though, surely they cannot be calculated, and we observe their effect on white light on the horizon.
 
Last edited:
Corkie2003 said:
What about the effect of miniscule particles though, surely they cannot be calculated, and we observe their effect on white light on the horizon.

If you mean the color of sunset, it appears redder only because much of the blue light has been blocked (scattered out giving that colour to the day sky elsewhere). The astronomical redshifts are where individual photons have all changed uniformly in colour. It might be hard to tell the difference for white light, but some of the atoms in these sources always produce lots of light at several very specific frequencies (so we can compare those lines in different stars spectra).
 
Redshift is all about how the universe conserves energy. When space expands, it preserves the net energy between point A and B by smearing it out across space. Without redshift, you have a universe that ignores the laws of thermodynamics.
 

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