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If there's a mechanism for space-time expanding faster than the speed of light, is there an example of It contracting in the same manner? If whatever mechanism is causing it to expand, can the underlying mechanism reverse itself?

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The equation of motion for cosmology from general relativity have a time reversal symmetry, even with a positive cosmological constant to explain dark energy. So any solution of the equations that features an expansion from a big bang can be reversed to give another solution in which the universe contracts towards a big crunch. In this solution the cosmological constant would slow down the rate of contraction instead of accelerating the expansion.

There are also solutions of general relativity in which the universe starts with an expansion and ends with a contraction after a moment when the expansion stops and goes into reverse. This is true even with a positive cosmological constant and even when space is flattened by the effects of cosmic inflation. The ultimate fate of the universes evolution depends on the size of the cosmological constant verses the rate of expansion after inflation. If the constant is too small or negative or the rate of expansion starts out too slow, then the universe would stop at some point and contract. However, observations indicate that this is not the case. The universe has already passed the point where the cosmological constant dominates and the expansion will continue to expand at an accelerating rate forever.

Of course this assumes that dark energy is correctly explained by a cosmological constant rather than a quantity that changes with time. All relevant observations so far are nicely consistent with this view.

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Both the early inflationary expansion of the universe and the "recent" accelerated expansion of the universe are thought to be driven by a positive vacuum energy content in space. The early inflationary expansion had a much larger positive vacuum energy density than the current accelerated expansion caused by the Dark Energy content of the universe.

So if some field were to produce a net negative vacuum energy density the expansion would become a contraction instead and for points that are far enough apart, the contraction could exceed the speed of light...

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