# Tag Info

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As you used only verbiage in your question, I think the most heuristic (reliably understandable) answer's offered by Einstein-Cartan Theory, which was developed by them in 1929, after the fact that subatomic particles spin had been discovered. In the cosmological model using ECT, the formation of a black hole occurs in the gravitational collapse of a ...

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How can we prove that the very early universe can be considered to be flat. The short answer is we can't prove that. Given the theory of inflation is correct then one can show (see "Flatness problem" linked by @John Rennie) that after the increase of the scale factor by many orders during that period the value of $\Omega$ (the ratio of actual to ...

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This is referring to the flatness problem. Specifically it is referring to the value of the parameter $\Omega$, which is the ratio of the density to the critical density. For a positively curved (closed) universe $\Omega>1$, for a negatively curved (open) universe $\Omega<1$ and for a flat universe $\Omega=1$. The question is inviting you to show that ...

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We can't exactly say what caused the universe to expand, because we don't know its origin. The Big Bang was not an explosion, at least not as far as we know: it was simply a moment in the past when the universe had a very high density. All we can really say is that according to the laws of physics (specifically, general relativity), the presence of matter in ...

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Without there being space or time before the big bang, the laws of physics wouldn't work. This means that everything possible AND impossible could and would happen in that instance. Without the conservation of matter in effect, matter was probably created at the big bang.

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Firstly, the big bang wasn't an "explosion". It just means that "at the start of the universe", if you want it to phrase like that, the spatial distance between every object was zero. It doesn't mean that the universe was shrunk to a single point. See Did the Big Bang happen at a point? for more information. But of course you are still ...

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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 ...

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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 ...

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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 ...

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It could be that the initial virtual matter fields were constrained to our 3d space, while our space was embedded in a highly negatively curved 4d space (somewhat as described in pyrotechnical approaches) The virtual character could induce this negative curvature. It pulled (or pushed) the virtual stuff into real existence in a bang. Thereby imparting ...

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Lets look at the data the General Relativity (GR) model is describing. GR is a theory as far as mathematics goes. In order to be relevant to physics it has to model the data of the universe(in this case). The data of the universe consist of numbers and observations of radiation and matter, if these are not there , there is no universe, only mathematics and ...

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Your question addresses deep issues about the beginning of the universe as described by 'Concordance Cosmology' and you are right that there are contradictions. The answer is that Concordance Cosmology is wrong. General Relativity and Big Bang are correct, but the extra additions that have been added since about 1990, inflation and dark energy are wrong. It ...

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The expansion of the universe is the relative motion of the stuff in it. It's meaningless to talk about expansion of a vacuum. There are vacuum FLRW solutions: they are Minkowski space (for $Λ=0$), de Sitter space ($Λ>0$) and anti de Sitter space ($Λ<0$). All of them are maximally symmetric—every spacetime point looks the same as every other—and so ...

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 ...

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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.

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How can we be certain that there is not an initial point of origin, and that all galaxies are not moving away from one another for the same reason that pellets from a shotgun all move away from each other after leaving the barrel? We cannot be certain, but the fact that the galaxies are all moving away from each other is not the key observation in this ...

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We know that the expansion of the Universe is accelerating and we can measure this. This acceleration already rules out the incorrect shotgun model, wherein the expansion is carried out by inertia/momentum. The true process of accelerating expansion is best modeled by the Friedmann equations, a solution of General relativity. The unique success of these ...

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Yes, but this explanation implies that we were at the center of that explosion. Only there you observe the situation as we observe it in the universe. I am aware of two main arguments against this explanation: One, the history of Copernican revolution tells you that you are betting on the wrong horse. Two, this is in violation of the homogeneity and isotropy ...

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