Proximity of early galaxies to each other

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The discussion centers on the density of early galaxies in the expanding universe, specifically regarding observations from the Hubble deep field. It is posited that galaxies appearing at distances of 12 to 13 billion light-years should be more densely packed than contemporary galaxies. However, the visibility of only exceptionally bright objects in deep sky studies complicates this assumption. Data from 2df quasar studies indicate that quasar density remains relatively stable, with peak density occurring 2-3 billion years after the Big Bang. This evidence challenges the steady state theory and is supported by findings from cosmic microwave background radiation and primordial elemental abundance.
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Given that the universe is expanding and galaxies in general are accelerating away from each other, I would assume that galaxies appearing in the Hubble deep field at a distance of 12 or 13B light years from us should be much closer to each other than is typical for galaxies today. Is this a correct assumption, that this "older" universe we view is much more crowded?
 
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The problem with deep sky studies is only freakishly bright objects are detectable at great distances. Using 2df quasar data, density [of quasars] is fairly stable over time. The greatest density actually occur around 2-3 billion years after the BB. This is not shocking. It takes time for things like quasars to form. This little hump puts a big hurt on steady state theory, as does CMB, primordial elemental abundance, and other solid observational evidence.
 
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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##.
Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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