Reality Check
Penultimate Amazing
I made a mistake.Anyway, please tell me; - If you can explain the cosmological redshift ONLY based on the expanding Universe / Space , - WHY did you then mix Doppler Effect into it , when you above was trying to explain the cause of Cosmological redshift ?
There is
- Redshift caused by the Doppler effect.
- Redshift caused by the expansion of the universe. This is equivalent to a "doppler effect" for each individual galaxy but there is a relationship called Hubble's law for all galaxies.
There isSo what you are saying now is that it ALL (the redshift) happens while the photon travels, - and I then suppose (nothing) due to DopplerEffekt, which was you first STAEMENT 1. ( or will you later jump back to horse 1 again ?)
- Redshift caused by the Doppler effect.
- Redshift caused by the expansion of the universe. This is equivalent to a "doppler effect" for each individual galaxy but there is a relationship called Hubble's law for all galaxies.
The point is that it is. There isBut the point in this part of the discussion is that DE has NOTHING to do the CR, - it is 2 independent phenomena’s.
- Redshift caused by the Doppler effect.
- Redshift caused by the expansion of the universe.
This is indeed a problem but not with cosmological redshift. It is a problem with GR that energy is not conserved in it except in special circumstances:The problem with CR is that when the (extension of a) photon can stretch (due to the stretching universe).
Hence the photon must lose energy.
We do not observe any kind of emitting / converting energy, - whereby we should know something could be wrong.
So the energy lost in redshift is either converted into graviational energy or just lost (since GR need not conserve energy).
But the problems with attributing all of the observed redshift to velocities of the galaxies are many, e.g.
- It makes the Earth a unique place in the universe, i.e. the place from which 100 billion (or ~10 million measured) galaxies are fleeing from. I wonder what we did to scare them so much
?
The Earth is in fact a small planet orbiting an average star in the outskirts of a modest galaxy.
It is a fundamental principle in science that tno point in the universe is special. - It means that in the past all of the galaxies were at one place (here!).
Then why did all this mass not form a black hole? - It means that in the past all of the galaxies were at one place (here!).
What force created the explosion that made all of the galaxies fly away? - How did this explosion magically leave the Milky Way at the center of the univserse?
- How did this explosion happen in exactly the way to produce the same effect as an expanding universe?
Hubble demonstrated that all galaxies and distant astronomical objects were moving away from us, as predicted by a universal expansion.[10] Using the redshift of their electromagnetic spectra to determine the distance and speed of remote objects in space, he showed that all objects are moving away from us, and that their speed is proportional to their distance, a feature of metric expansion. Further studies have since shown the expansion to be extremely isotropic and homogeneous, that is, it does not seem to have a special point as a "center", but appears universal and independent of any fixed central point.
And an intersting paper that measured the tempertaure of the cosmic microwave background at z = 2.3371 and showed that it was hotter as predicted by an expanding universe:
The cosmic microwave background radiation temperature at a redshift of 2.34
The existence of the cosmic microwave background radiation is a fundamental prediction of hot Big Bang cosmology, and its temperature should increase with increasing redshift. At the present time (redshift z = 0), the temperature has been determined with high precision to be TCMBR(0) = 2.726 +/- 0.010K. In principle, the background temperature can be determined using measurements of the relative populations of atomic fine-structure levels, which are excited by the background radiation. But all previous measurements have achieved only upper limits, thus still formally permitting the radiation temperature to be constant with increasing redshift. Here we report the detection of absorption lines from the first and second fine-structure levels of neutral carbon atoms in an isolated cloud of gas at z = 2.3371. We also detected absorption due to several rotational transitions of molecular hydrogen, and fine-structure lines of singly ionized carbon. These constraints enable us to determine that the background radiation was indeed warmer in the past: we find that TCMBR(z = 2.3371) is between 6.0 and 14K. This is in accord with the temperature of 9.1K predicted by hot Big Bang cosmology.
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