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B Could a parallel universe exist?

  1. Jul 12, 2016 #1
    I'm just being introduced to quantum mechanics and physics, and I was wondering if the possibility of a parallel universe could exist. And if so, how do we know? I read some articles about the research done with Australian researchers who theorize that parallel universes do exist and interact as well.
  2. jcsd
  3. Jul 12, 2016 #2


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    To the best of my knowledge, they could exist, but we have no way (at present) to definitively answer the question.
  4. Jul 12, 2016 #3
    We don't know that there is more than one universe, just that some theories of quantum physics allow for the possibility.
    If other Universes do exist then they cannot interact with the Universe we are in since if they did they are intrinsically a part of the same system, and not something equivalent but 'Parallel'.
  5. Jul 12, 2016 #4


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    You nailed it ! ... :check:
  6. Jul 13, 2016 #5
    Quantum mechanics has several interpretations and the "many-worlds" interpretation (parallel universes) it is just one of them. I recommend you to read the works by Hugh Everett if you have some knowledge in quantum mechanics, who was the first who formulated it.

    I think that another interpretation that us gaining some pupularity is quantum decoherence. They are not the only ones and, at the moment, I don't think we know which is the correct.

    Just investigate and get your own conclusions!
  7. Jul 13, 2016 #6
    Dear wannaberadiologist,

    As you know, in 1926 was formulated by Erwin Schroedinger a partial differencial equation that describes how the quantic state of a physical system changes with time. For it, in 1933, he received the Nobel Prize (together with Paul Dirac).

    It contains the factor Ψ, referred somewhat improperly as "wave function". The significance of it was not understood, until Max Born interpreted it as defining the probability of finding a particle in a determinate position of space. He received the Nobel Prize for it in 1932. The possibility can be represented by a Gauss curve, with maximum in the center and coming asymptotically to zero in the extremities. The mathematical formalism adopted leaves clear that in the instant the location of the particle is made, all probabilities disappear. Strangely, since the formulation to this day, numerous discussions about the significance of this disappearance occur, maintaining that there is something misterious in it (Copenhagen interpretation). Nevertheless, when we have a dice in hand before we throw it the possibility of each face falling upside is one to six. In the moment it falls upon the table and immobilize, to us it's clear one can no more speak of probabilities, as one of the faces was defined. Its obvious, there is nothing mysterious in it, as even Einstein and Niels Bohr concurred. A supposed “observator's influence” is therefore nonsense, analogous to Kant's discussion of the Moon's existence when no one is looking to it.

    It's what occurs when one imagines that Physics necessarily must be described by mathematical formulas, even when they are not needed, as is the case. In this love for mystery, even today is frequent the understanding that the wave function signifies that the particle is in all places at the same time, and quantum theory would make possible the creation of a computer capable of realizing simultaneously infinite mathematical operations, a thing that would be useful, for instance, in breaking cryptographed texts. We must have present that Mathematics is a tool, albeit useful, but only an instrument. In his celebrated novel "Stranger in a Strange Land" Robert Heinleim created the neologism "to grock" meaning a profound, almost subconscient knowledge of some theme. Perhaps what is needed is "grocking" the physical fenomenon before using mathematics to better understand the details of it.

    I suppose another common mistake that has the same origin consists in "multiple universes interpretation", that erroneously affirms the objective reality of the universal wave function. As I see it, that makes no sense at all. Observe that Schroedinger's equation is completely deterministic, aleatority is an emergent property.
  8. Jul 13, 2016 #7


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    Decoherence is not an interpretation. It is a result predicted by quantum mechanics itself, so it happens completely independent of your choice of interpretation.
  9. Jul 13, 2016 #8
    Right. I didn't express it properly.
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