Could Black Holes Lead to New Universes?

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The discussion explores the concept of whether the expansion of the universe leading to black holes could result in the formation of new universes through multiple big crunches. It highlights that while black holes consume mass, they also contribute to increasing the universe's entropy via Hawking radiation, ultimately leading to a state of equilibrium rather than a big crunch. The distinction between black holes and the big crunch is emphasized, noting that the latter involves the universe's gravity halting expansion and collapsing into a singularity. The idea of creating multiple universes is linked to current speculative physics, referencing Sean Carroll's work on time and entropy. Overall, the discussion presents an intriguing but complex relationship between black holes, entropy, and the potential for new universes.
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Random musing:

Could it be that sufficient expansion of the universe that leaves behind only black holes that have gobbled up all the mass, lead to several big crunches, and eventually several new universes?
 
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Based on my understanding, this wouldn't happen for a couple of reasons:

First, while all the matter being gobbled up into black holes is a possibility for the fate of the universe there is still further development that increases the entropy of the universe even further (following the entropy based arrow of time). This is Hawking radiation, where black holes slowly decay, leaving behind a featureless and constant collection of particles - the highest entropy point (equilibrium).

Also, the collection of matter in a black hole is not the same as the Big Crunch. The Big Crunch, if it occurred, would result from the gravity of the matter in the universe slowing the universe's expansion to a halt and re-collapsing it into a singularity. This is not the same thing as a black hole, although both involve singularities. For a simple explanation of the difference between the Big Bang (or Big Crunch) singularity and that of a black hole visit: http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/011030a.html
Or for a more technical explanation visit: http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/universe.html

It's a cool idea though and something sort of similar is being tentatively explored by physicists right now. I read about the idea of multiple baby universes being created in Sean Carrol's From Eternity to Here. It is a great book exploring the arrow of time and entropy, as well as some speculative stuff based off of that. A link in Physics Forums discussing the idea is: https://www.physicsforums.com/showthread.php?t=469255
 
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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