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Our current universe is expanding, and distant galaxies are redshifted, with a redshift that increases as the distance to the galaxy increases. After a certain distance, the galaxies move faster than the speed of light, the redshift becomes infinite, and we get a kind of event horizon past which we can't see anything.

Now, how would that look like in a contracting universe? Would further away galaxies move faster towards us? If so, does that mean light would be blueshifted, and the further you look the more shifted it is? Would there be a point past which galaxies seem to be moving towards us at the speed of light? What would that even look like?

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I am not sure about your question as contracting universe will be against 2nd low of thermodynamics, the entropy is decreasing. Otherwise I think. Your guesses are right just put - sign in Hubble's law. Hope this helps.

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  • $\begingroup$ A contracting universe wouldn't be against the 2nd law, it's just what would happen if the universe was dense enough to overcome dark energy and inertia. My point is... that there's definitely something off, for me at least, about an infinitely blueshifted thing. $\endgroup$ – Eric Vilas Jun 4 at 5:02

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