Comments by "Mosern1977" (@Mosern1977) on "Чем на самом деле является Великий Аттрактор?" video.

Just wanted to clarify one thing - we have not detected expansion of space. We have detected that far away galaxies have light red-shifted. It is assumed that this red-shift is caused by an expansion of space, but the expansion has never been measured directly.
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@markburch6253 - We have only measured galactic redshift of light. It is an assumption and hypothesis that this is caused by the expansion of space itself. We have not measured this expansion. It is a hypothesis. (Earth is at least 1/3 as old as the universe - if this expansion was real and affected everything - the earth, the sun, the distances between them should have been 1/3 as big in the early solar system. This has clearly not been the case).
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@markburch6253 - yes, that's the story. And therefore the expansion has not been actually measured. It is a hypothesis. But maybe you can answer me this, in the early days of the universe - say 400.000 years old, or 1 million, the density was way higher than now. How could this expansion work back then, as there were no places without matter.
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@markburch6253 - exactly so you have matter and gravity - and expansion of empty voids of space (because, as you pointed out, expansion only works in very large voids). Have you done some calculations on average density at say 500.000 years after BB? Pretty sure you cannot have any expansion of space with the average density at that time.
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@markburch6253 - well, I'm purposely taking a time after recombination and CMB, as that is when we're at some sort of situation that I can mentally relate to. So, say 500.000 years after BB. At that point in time we have atoms and gravity working, and the universe is still very small, and we are out of the "magic areas" of the universe's birth hopefully. So care to give an guestimate of the size of the universe at 500.000 years of age - that's a good 120.000 years more than estimaged age of CMB? And how many galaxies worth of matter you have in it, because at this time there is actual matter (hydrogen) all over the place. Bonus points for calculating the expansion speed of the universe at that time given a Hubble constant of 70km/s pr Mpc.
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@markburch6253 - So a couple of dozen million light years across then? Must have expanded way faster than speed of light, but anyhow... And given that you can put say 10 galaxies in a million light years. So that space could perhaps cater to maximum 1 billion galaxies stacked really tight. And there are a lot more galaxies out there, maybe 100 or 1000 times as many (better telescopes gives higher numbers). Say I lived in a "galaxy" then, with stuff stacked all over the place - how come the universe expanded and not recollapsed. There was no "empty voids" back then. Just matter all over the place. Some other mechanism in place causing this faster than light expansion, because Dark Energy doesn't do the trick? Hubble "constant" is also not constant apparently - what values did it have back then?
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@markburch6253 - the whole point of the BB theory is to have all stuff and energy in the universe beginning at one point in time. There is a point of creation. After a CMB happens, the universe is now apparently about 15 Mpc big (still with average density probably higher than lead (haven't done the math, but we're in instant black hole land for a couple of more billion years at least). Expansion rate is clearly waaay above light speed (ludicrous speed perhaps - Hubble "constant" being like 1000000 km/s pr. Mpc or something?) and nothing is following any known laws of physics for the next couple of billion years. Suddenly these hydrogen atoms (that have been expanding away from each other at ludicrous speeds for eons) finding it good to start thinking of gravity for a bit, and start collapsing overcoming the fact that they have been moving away from each other all the time at way over light speed. Then this slows down the expansion (really? What sort of expansion speed now? Warp 9?) and then after a while it started expanding more eventually by pure Dark Magic eh Dark Energy, and now we end up with a Hubble "constant" of 70km/s/Mpc - but it cannot be measured in a lab of course (even if it would be trivial to do) - because "eh - the expansion is so 'weak'". I mean - the creation mythos in the Bible is more coherent than this dribble. I don't understand how anyone can say all this with a straight face.
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