Evidence of Expansion: Redshifting of EM Radiation

Calimero
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Are there any evidence that universe is expanding other then redshifting of EM radiation?
 
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The existence of the CMB shows that the universe was once a lot hotter and denser, which is the conclusion you reach if the universe is expanding.
 
The redshift in the EM radiation from galaxies increases in proportion to their distance from us.

If interpreted as a Doppler shift, galaxies are rushing away from each other, matter inside galaxies remaining largely unaffected. This interpretation has lead to the Big Bang model, which has been so eagerly defended against evidence by postulating inflation, dark matter and dark energy.

It can also be interpreted as a successive shrinkage of space-time, if it is assumed that light is not shrunken. This leads to various models of the Universe that are dispreferred, mainly for non-scientific reasons.

Although some text-books say so, the redshift cannot be interpreted as due to an expansion of space as such. Such an expansion could not be observed, unless the light was not expanded on its way. But in this case, we would see a blueshift.
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
Hi, I’m pretty new to cosmology and I’m trying to get my head around the Big Bang and the potential infinite extent of the universe as a whole. There’s lots of misleading info out there but this forum and a few others have helped me and I just wanted to check I have the right idea. The Big Bang was the creation of space and time. At this instant t=0 space was infinite in size but the scale factor was zero. I’m picturing it (hopefully correctly) like an excel spreadsheet with infinite...
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