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B In parallel universes, everything that can happen happens, but why?

  1. Jul 13, 2018 #1
    Hello,
    on quantum theory of parallel universes.
    It seems quite ridiculous to me, in quantum mechanics everything, that's not forbiden by rules happes.
    Are there some theories why it may be ??? Or is it to early to even speculate about that.
    Elon musk said, that there is chance bilion to one, that we are in computer simulation.
    Perhaps our creators, just testing something out, and bilion years here, is like couple days for them, or weeks, or 3 minutes perhaps :D
    Why would they care about us ? We also smash bugs and don't even thing about it, it is quite depressing to me.
     
  2. jcsd
  3. Jul 13, 2018 #2

    Drakkith

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    Why? It's just simple probability. If you roll a trillion dice over and over and over, you'll eventually roll every single possible combination.
    Also, the multiverse theory is more accurately an interpretation, not a separate theory itself. It's just one of several possible ways of interpreting quantum theory.

    Elon Musk has no idea what the probability is that we are in a simulation. No on does.

    Meh. It doesn't keep me up at night. :biggrin:
     
  4. Jul 13, 2018 #3

    Mentz114

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    Take heart, It is ridiculous and furthermore it is not standard quantum mechanics. Don't lose any sleep over this.

    Standard quantum mechanics includes the operator theory which states that observables are represented by operators and the probability of an outcome is determined by the eigenvalues of the operator.
    This is thrown out in MW and replaced with "every possible outcome happens once". How can they still be the same theory ?
     
  5. Jul 13, 2018 #4
    Ye but a lot of physisist share this opinion, that it is very like so, i read on bbc.
    We already making pc games and consciousness, is just chemical and electrical reactions in brain, it is biological computer created from iorganic mass.
    And because we will be able to do same thing, ray kurzwell is saying, that we will be able switch our bodies rapidly in virtual world,
    undistinguishable
    from reality, where is pain and pleasure and feelings.

    Exactly why is there happening every possible combination at the same time, it is just absurd.
    What could be reason for that ?
    So in some parallel universe i die in fire for example, so fun...
     
  6. Jul 13, 2018 #5

    Drakkith

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    And a lot of physicists do not. And both groups use the exact same underlying math and make the exact same predictions for any observable experiment. There is utterly no evidence that parallel universes exist, so the idea should be treated with a healthy amount of skepticism in my opinion.
     
  7. Jul 13, 2018 #6

    Nugatory

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    Staff: Mentor

    If you want to learn physics, read textbooks, not news sources - not even reputable ones like the BBC. What you've been hearing isn't a serious explanation of the multiple worlds interpretation (MWI) of quantum mechanics, it's closer to an urban legend.
     
  8. Jul 14, 2018 #7

    bhobba

    Staff: Mentor

    You are just saying some of things promulgated by popularization's. The theory is in fact very precise on such things with one thing that linguistically perhaps is imprecise, The rest is very precise.

    I will state the two axioms from which everything follows - although at the beginning level you are not likely to understand it (it requires linear algebra which most do not do until university - although I believe is should be at HS - but that is another issue and another thread).

    1. Associated with every observation on a system is a linear operator, O, whose eigenvalues give the possible outcomes of the observation.
    2. The average of the possible outcomes is given by the formula Trace (OS) where S is a positive operator of unit trace, by definition called the state of the system.

    Interestingly 2 can to some extent be derived from 1 using something called Gleason's theorem:
    https://en.wikipedia.org/wiki/Gleason's_theorem

    That it, that's all. A good textbook like Ballentine - QM - A Modern Development derives all of QM from just those two axioms. But unfortunately is advanced - you need to build up to it with a beginning and intermediate course in QM first, as well as courses in calculus and linear algebra.

    Now you see the single imprecise thing - observation.
    1. What is an observation.
    2. When exactly does it occcur. That's part of the concept of collapse which some interpretations have - but others do not. However I will also tell you some believe collapse is inherent - some do not (I am in that camp).

    There are probably others as well.

    Much work has been done in sorting it out. I will not give the possible answers here - they are involved with interpretations on which there are many:
    https://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics

    The idea we are living in some kind of simulation is a rarely held one.

    Thanks
    Bill
     
    Last edited: Jul 14, 2018
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