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Multiple universe theory

  1. Oct 22, 2006 #1
    I just had the coolest thought about the multiple universe theory. Pretty much anything is possible in this theory right? each universe can have seperate laws of physics, different quantum outcomes, etc. Also, the only reason we exist in this particular universe is because we exist in this particular universe (not sure how clear that is but anyone who knows this theory probably knows what Im talking about). We can change universes without knowing it, and if in some universe we dont exist, we cant be in that universe. Therefore, we cant die! If we were to die in some universe, our consciousness could no longer be in that universe. However in some other universe, because of multiple very unlikely quantum differences, we are alive. It would seem to us like we were just always in that universe, and that in some other universe some other version of us died. yes, people die every day, but they cant know their dead. All they can know after their dead in this universe is that they are alive in some other universe with an identical past as ours.

    comments? I think this is an awesome idea and it seems like if multiple universe theory (wish I could remember the initials for it, Im kinda drunk) is correct, then this would be also.
  2. jcsd
  3. Oct 22, 2006 #2


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    IF you are referring to the "many worlds" theory of quantum theory: that every time a wave "collapses" every possible observable value does occur, spawning multiple universes, then, no, the laws of physics cannot differ. The result of any experiment on any one "universe" must be one of the allowed by quantum physics.

    (By the way, the word is "they're", not "their".)
  4. Oct 22, 2006 #3
    sorry, like I said I was drunk. whether or not the laws of physics can be different has nothing to do with my post. For any situation in which someone dies there is another, possible very unlikely, situation in which the person lives due to a bunch of random quantum effects. MWT thats what I was looking for thanks.

    also, I remember reading in some article that the laws of physics could be different in other worlds because of the splits occuring at the big bang. But like I said, its completely irrelevant because we are stuck in a universe that obeys our laws.
  5. Oct 22, 2006 #4
    o COMON why was this moved?
  6. Oct 23, 2006 #5
    whoever moved this thanks alot! you moved it to a forum noone reads...
  7. Oct 23, 2006 #6


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    I second that thank you.
  8. Oct 25, 2006 #7
    That's a possibility. As for your other speculations, they were more along the lines of asking how many angels can dance on the head of a pin. :uhh:
  9. Oct 25, 2006 #8


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    I think you're refering to the anthropic principal.
    Max Tegmark wrote an interesting paper on this in 1998.

    You might want to read some other links here:

  10. Oct 26, 2006 #9
    thanks a lot for the links, I had this idea while I was trying to go to sleep drunk. Thought it was pretty cool that according to MWT we can die.
  11. Oct 26, 2006 #10
    Do your really believe in death?
    I know that a ‘law of information’ is mathematically unsustainable, but then why trusts maths? It doesn’t seem to work anyway unless you keep shoving in constants.
    When all the wave functions in your brain collapse, and your perception loses that macro host and becomes entangled in the quantum mischief of immortality, maybe your perception survives as some discreet unit of quantum information that moves through unconsidered dimensions to entangle with ‘your perception of a different now‘.
  12. Oct 26, 2006 #11
    This is by far the most interesting question in the universe (at least that I know of), and in my opinion, the answer can be found in the question: "What makes me me, and you you?". If the sperm behind "me" 25 years ago had won the lottery and not my candidate, would I (as me or as anybody else) existed today then? And if the answer to that is "no", then we should conclude that what makes me me, is some sort of combination that appeared in the mix of that sperm and that egg. But what if the same combination by luck (at least for me) had appeared after another egg and sperm had mixed together. Would "I" existed then? And why not if we have concluded that I AM that combination?

    My view on this is that if a multiverse exists (either the multiverse as explained above here, or an eternal inflation multiverse, or a brane multiverse, or whatever), and this multiverse is infinite and produces universes forever, then some day, that exact combination that makes "me" will appear somewhere (as it already has), and if that is true, then each and every of us are no "miracles" in contrary to what we might think.

    If we look at the shotgun example above, we can clearly see that we have already survived billions of potential shots against our head. I mean, take the sperm+egg mix example, and multiply your lousy odds for every generation back to the time when human started to exist in this universe. The probability of you sometime in this universe to exist was as close to zero as you can get, but still, in some universe, those small chances did happen, and accidently, it was in this exact universe.
    Last edited: Oct 26, 2006
  13. Jan 9, 2007 #12
    That is not necessary the case, since the number of possibilities and outcomes of "universes" are so innumerable, that even when there is no limit to time, it is not a necessity that unique combination of events and possibilities that "make you you" are going to reappear.

    Likewise, mathematically speaking, if you have the innumerable possibilities of all natural numbers at your disposal (a set which has infinitely many numbers) and you can pick for any natural number a real number (just by chance or even selectively), no matter how hard you try and even when exhausing the total set of all natural numbers, there will always be an infinite amount of real numbers, you haven't selected.

    Probability analysis on such non-quantifyable processes are more confusing then in helping to understand the real world.

    Even a lottery which has a chance of winning a price of 1 in hundred thousand billion trillion zillion (etc.), does have a winner, so actually the chance someone gets the prices is exactly one.
  14. Jan 29, 2007 #13
    Cool, this idea has been bugging me all year but this is the first non-SF reference I have found to it. I think my first exposure was Permutation City (SF which used Virtual Reality) and then there was a short story called something like 'split infinities' (SF which used 'Many Worlds' interpretation)

    My big idea, which I think VikingF also has, is that it doesn't need quantum mechanics, just for the universe to be big enough; ie what if everything happens somewhere.

    I dont believe in any supernatural soul, so as a consequence
    • If I walk into a teleport machine and it makes a copy of me at a distance, and forgets to destroy the original, then questions of which is the 'real' me are meaningless.
    • When teleporting, nothing supernatural (soul or QM gobbledeegook wave) needs to pass between the initial and the final copy to make it 'really me'
    • The teleported result does not need to be exact. Assuming they are approximately the same, I aproximately continue to exist.
    • From the above, a copy of me created at a vast distance, by shear statistical probability is (approximately) as validly me as a teleported version or a 'stay-at-home' version.
    • If the version-at-a distance had it's own entire history which by some fluke just happens to produce the same brain with the same memories, it is still just as validly me. there is no 'it already has a soul' principle.

    The other thing I was wondering was if this could actually be an explanation for the fuzzyness of the world on the very small scale. If we are 'teleporting' all round the universe, a zillion times a second, to one of our infinite copies, then how close does that copy need to be? The answer might be what we are witnessing with quantum mechanics.
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