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10

The photon to baryon ratio prior to decoupling is $1.6\times 10^9$ (e.g. here). i.e. There are roughly a billion photons for every proton/electron pair. Therefore the CMB is not produced by recombination of protons and electrons, that process merely facilitated the CMB by making the universe transparent at that time. However, neither can you say that the CMB ...


6

However I read somewhere that it was actually the decoupling event itself which was what originated the CMBR. Much like flame tests, or by Bohr's 2nd postulate, when electrons relax into ground state or just lower energy states, emr is released. Hence, would the relaxation of these electrons be the source of the CMBR? The CMB has a near perfect blackbody ...


12

Once recombination occurred, the black-body radiation, which was in thermal equilibrium with matter (hydrogen plasma), became decoupled from it and was free to propagate. The temperature at which this occurred was about 3000 degrees kelvin. This means that the CMB is composed of the radiation which existed right before the decoupling i.e., what was flying ...


2

It's ok. Compare the situation with having a house on planet Earth. To describe goings-on in the house, the rest frame of the house is a natural choice, a sort of "preferred frame". But this does not break the principle of relativity; it is not a "preferred frame" in that sense. The frame in which, at the large scale, stuff in the ...


0

The mean free path of a CMB Wave function (assuming Copenhagen interpretation) would be no more than a few metres on average over the 13.5 billion years of travel, if we assumed an ion or dust mote every metre or so. The wave function would collapse and a new slightly lower energy photon would be created because the ion or dust would gain some tiny amount ...


4

Microwave radiation spans frequencies from 300 MHz to 300 GHz. Visible light, on the other hand, spans frequencies roughly from 430 THz to 740 THz. As you can see, microwave is too far away from the visible range (several orders of magnitude) to be visible by the human eye.


2

Light traveled from there to here, therefore the scattering events seen by us are at a null interval from us. Up to small corrections those events lie on a spatial surface in the past. To get the idea, throw away one spatial coordinate for a moment, and then you have a circle lying at a moment of cosmic time in our past light cone. Coming back to all three ...


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