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I Dark Energy and the Cyclic Universe?

  1. Oct 15, 2017 #1
    Now two points here. (1) Most Cyclic Universe theories I've heard require the universe to reverse course and fall back into a Big Crunch to recycle again. Now that Dark Energy has been discovered, the chances of a Big Crunch have gone away. (2) Some theories suggest that the universe started with a massive quantum fluctuation, the kind of which we have never seen since.

    So my question would be why have we not seen another Big Bang level quantum fluctuation again? My assumption is that the presence of having the current universe here right now is itself the reason why such massive fluctuations have not reoccurred. Perhaps the structured universe itself suppresses the biggest fluctuations?

    So, what I'm thinking is that once Dark Energy clears out the present universe, leaves behind mainly empty voids, then that will clear the way for more massive fluctuations to occur. This may start a brand new universe in all of the emptiness. So the Cyclic universe models would still work, it just won't be with a Big Crunch associated with it too. What do you think?
  2. jcsd
  3. Oct 15, 2017 #2


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    There are many possibilities, the most general one is that the idea that the big bang was the result of a quantum fluctuation is an incorrect explanation. There may be an unknown force or an unknown behavior of the existing forces at the scale of the big bang that caused it.

    I can't see any reason to believe this. Further expansion should lessen the possibility that such a fluctuation would occur, not encourage it as far as I understand.
  4. Oct 15, 2017 #3
    Yeah, I completely agree, it's not the only possible theory for why the BB began, but we're only talking hypothetically here. One possible scenario.

    Well, the reason why we would expect this is because it's been shown that within the volume of an atomic nucleus, the energy of the Strong Force's gluons suppresses quantum fluctuations much larger than virtual quarks from existing. What if a similar suppression field exists throughout the universe as a whole, keeping the quantum vacuum fluctuations in check? Thus we may see virtual electron-positron pairs popup, maybe some Higgs bosons, and quark-antiquark pairs, but nothing much beyond that. So we won't see virtual Saturns popping into existence and annihilating. Well, obviously I don't mean an actual Saturn with rings and stuff, just a particle with the mass of Saturn.
  5. Oct 15, 2017 #4


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    I'm not sure what you mean by this.

    There is no such thing as a "suppression field". I'm not sure what you talking about in the part of your post I quoted above, but whatever "suppression" is occurring is going to happen because of the existing conditions within the nucleus and the existing fundamental interactions. In addition, it would be difficult to extend this principle to the universe as a whole, since there are already huge volumes of space that are devoid of matter beyond a handful of particles per cubic meter. Also, whatever virtual particles are created, they are, in the end, virtual particles only. They don't suddenly turn into real particles. That would violate conservation of energy and probably a few other conservation laws as well. We can't even observe the particle-antiparticle pair creations and annihilation, since they are virtual.

    Please keep in mind that we're skirting the edges of PF rules here. Speculation like this is not something we generally allow, since it inevitably leads nowhere. If you can find some reputable published articles discussing what you're proposing then feel free to link them.
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