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Parallel universes collide?

  1. Aug 24, 2009 #1


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    If we were to take the multiverse paradigm, and there are multitude of universes which do not intersect and thus don't collide, to truely be parallel there shouldn't even be a wormhole between the universes.

    Suppose that wormholes were a possibility, and they were stable, then also the possiblity of collision between parallel universes would be a possibility (like the alleged collision that should happen between the milky way and andromeda if I'm not mistaken), which makes me ponder, shouldn't we need a background also for this multiverse, what there is between these universes, are the universes dense such that the question is there something in between is meaningless?

    Are there any textbooks which detail my specific connundrums, perhaps Weinberg's and Piran's: "Quantum Cosmology and baby universes"?
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  3. Aug 24, 2009 #2


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    Another thing that popped into my head right now, is if there were other universes and there were wormholes between possible universes, then in this process objects foreign in one universe (i.e weren't detectable in it) would transfer from the foreign universe and vice versa, wouldn't this exchange violate conservation of energy, we might gain more energy in our universe in this exchange if the processes isn't symmetric, e.g we create a wormhole in the other universe in a place wich has less mass from the place in our universe which we started the wormhole.
    Ofcourse also particles can get lost when the link between the universes is destroyed, and then what'd be with them?
  4. Aug 26, 2009 #3
    Parallel 'universe's colliding would be a topological change, which complicates a model; likewise for Linde's eternal chaotic universe, with budding of baby universes. Also the antithesis of quanta and manifold of our "universe', would be simply there absence; unless something ad hoc were added, like a 21th century ether.
  5. Aug 26, 2009 #4
    But why does there need to be anything in the background for these universes to exist in? If there is a multiverse, couldn't all of them exist simultaneously? Note that in particle accelerators, when two particles are created, one disappears almost instantly. Where does it go? According to currently accepted universal laws of conservation, they can't simply have just ceased to exist, they need to exist somewhere. Also note, in these same accelerators, matter seems to pop into existence out of nowhere.

    Now, take these two different events and combine them. It would appear that perhaps we are witnessing the same event from two different angles. When a particle disappears out of our universe, it appears, seamingly out of nothing, in the other universe.

    The laws of conservation in the multiverse would be practically uniform across all of the various universes. In this case, no matter is truly lost, merely transported to a different area, and, being interlinked much the same way all systems on Earth are linked, there is no true loss in any one area, since all areas are in fact, the same area. It would follow that it is our own flawed perceptions of the mechanics of the universe which leads to a perception of separate yet equal universes.
  6. Aug 27, 2009 #5


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    A parallel universe colliding with our universe would necessarily become part of our universe. This is a non starter. We live in an amazingly homogenous universe, which tends to refute the prospects of any 'collision' with parallel universes.
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