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Possible to exist again in the future?

  1. Nov 7, 2007 #1
    I just remembered an idea that was presented in one of my math text books when I was an undergrad. The basic idea was that if you consider every single atom in the universe, the number of atoms is certainly beyond what the human mind could comprehend, however, the number of those atoms is still finite. Given a finite amount of things there are only a finite amount of ways that they could be arranged. Now, given an infinite amount of time, would the same atoms that compose your body at this very instant be able to arrange themselves in the same way that they are now in the very, very, very distant future since there are only a finite amount of permutations possible? That is, would you be able to exist the same way that you do now, in the future?

  2. jcsd
  3. Nov 7, 2007 #2


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    No, because the position of the electrons is also important. Our brains use electrons to process information and such, so there positioning and use must be the same also. So it might be you, but not the conscious you. Therefore you look like yourself, but you're not yourself at all.

    There are no finite number of places an electron can be. (As far as I know.)

    Also what you're saying is that one of you can also exist on the otherside of the universe? What happens when two versions of you exist simultaneously in the conscious sense?

    Really interesting.

    Send to philosophy!
  4. Nov 8, 2007 #3
    this is related to quantum immortality- the idea that in a quantum multiverse there is always a non-zero chance of survival even in a certain death situation since every possible outcome of physical events is realized- so an observer will continue to exist in histories that they survive and ones they do not are by definition unreal since the observer doesn't exist in them- the observer sees the sum-over-histories and since there are always histories that they survive and they cannot see the histories where they die they since they are not conscious in these: they always observe surviving

    the reason for quantum immortality ultimately rests on the understanding that if all possible histories happen- by definition in some of these your current state will be exactly duplicated which is equivalent to moving or teleporting to that history- this is because in a transfinite universe/multiverse any discrete physical system with finite information and relations will be repeated infinitely- with every possible history every possible event expressed somewhere/when- since humans are discrete collections of atoms and their minds are the physical equivalent of bit registers of around 10^15 bits- then any human will find that regardless of their local mortality- they will be eventually reconstructed and live on from any possible death event- you also must deal with the fact that at any given moment there are an infinite number of identical copies of you and your locally observable environment in the universe/multiverse [ Max Tegmark calculates that the nearest copy of you is 10^{10^29} meters away]- since what we perceive as space and time are abstract expressions of information relationships- one should not consider these copies as separate in space and time- they are the entangled Born Probabilities of your body and mind's matter and the space and time between them is invariant of the fundamental quantum information relationship- like a complex sorting algorithm which continuously refers back to some specific sub-routine and uses the results in different parts of the computation- your structure is an ensemble of possible histories that are reconstructed throughout the cosmos yet remains entangled with itself since the relationships and information of your causal structure express "you"- not the matter/energy or location in space and time-

    this is a hard mathematical certainty of any finite set of causal relations embedded in an infinite state space - so you are correct

    the electron clouds of atoms can only form 94 stable structures in nature- and your body only uses a few of these- the electromagnetic properties of your molecular structure form quite general and predictable building-block relationships that are repeated infinitely in an infinite universe- as are all discrete relationships of matter/energy
    Last edited: Nov 8, 2007
  5. Nov 8, 2007 #4


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    Well, one problem preventing it is entropy. Once the universe has cooled and its heat has been distributed, entropy will have reached maximum and the universe will never recombine into more complex structures - even given infinite time.

    Unless of course, there is some intervening event - such as a Big Crunch - that resets the entropy to low.

    However, a universe that is infinite in dimension will have the properties you mention. There was a Sci-Am article a couple years ago that demonstrated that, in a universe of unlimited size, there is a duplicate of you a mere 10^500metres or so away.
  6. Nov 8, 2007 #5
    It's a fluke of nature that finally in 4.5 billion years of Earth's evolution humans have evolved. If the existence of the universe is infinite, it would be possible for same conditions to arise elsewhere in space and time. Before they do, all variations and possibilities of earth, and histories would occur infinitely before a perfect copy of ourselves arises.

    That could happen if the universe is infinite, and will never reach maximum entropy, or possibly new big bangs will arise like said before.
    Last edited: Nov 8, 2007
  7. Nov 15, 2007 #6
    One flaw to the distant future "you" is that it wouldn't actually be "you". It may look exacly like you, but it will have different experieces, and thus grow to be a different individual than the "you" of today. The only way to recreate "you" is for your personal timeline to exactly repeat itsself. Otherwise it's like having a twin brother, but not another you. Also, you have to assume finite variables and a nearly infinite timeline to get the physical recreation in the first place.

    There's a similar argument presented with a teleportation device, which would scramble your atoms, store them electronically,send them to the data stream, and reassemble them at the other end, in essence recreating "you".

    Now, assuming every atom of your physical self could be duplicated (or reassembled if you prefer, but really it's just a reconstruction) Would the "you" at the other end still be you, or an entirely new individual that exactly duplicates you? Personally I feel that a clone, no matter how exact the duplication, is still a clone. Even if the clone is retains everything of your memories synapses and dendrytes, it's a photocopy, and the original dies in the teleporter. The "new you" is born each time you teleport. Personally, I'd rather not die each time I teleport.

    you are a snowflake;)
    Last edited: Nov 15, 2007
  8. Nov 15, 2007 #7
    Its conceivable, so are flying pigs.
  9. Nov 15, 2007 #8


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    No. The point is, given the preconditions, it's inescapable.
  10. Nov 15, 2007 #9
    If atoms were the smallest unit of quantity,
    and if they never disappear,
    and if they are finite in number.
    And if time was infinite.

    We know number one is false and we have no idea about time.

    So Right, if pigs had wings they could fly.

    Inescapable, if pigs actually fly.
    Last edited: Nov 15, 2007
  11. Nov 15, 2007 #10


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    I don't know where you get all those ifs. You seem to be putting words in your adversarie's mouths and then refutng that.

    It only needs one if to be inevitable. Here are two:

    If the universe is physically infinite (and we can't be sure it's not), then it is inevitable that there is another us somewhere.

    If the universe refreshes itself in time (say, repeating Big Bangs) ad infinitum (and we can't be sure it doesn't), then it is inevitable that there will be another us somewhen.
  12. Nov 16, 2007 #11
  13. Nov 16, 2007 #12


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    Well no, but eventually the universe will reach equilibrium and - unless the curvature of space is large enough to bring it back together again - that will be it for the universe. That much I'll grant Dawg.
  14. Nov 16, 2007 #13
    Infinite as mathematical concept is valid and useful. Physically infinite is so meaningless as to be nonsense.

    Unless there are an infinite number of possible universes.
  15. Nov 16, 2007 #14
    I'll let you know in a hundred years.
  16. Nov 16, 2007 #15


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    Alloe me to modify: It doesn't have to be infinite, merely very large. And, no that's not just bifurcating bunnies: as mentioned, in a SciAm article a while back, they calculated how wide the universe would have to be in order for it to inevitable that our area was repeated. The number off the top of my head was something like 10^500 metres.

    That is a third way we can exist in duplicate, yes.
  17. Nov 16, 2007 #16
    Or not.
  18. Nov 18, 2007 #17


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    This thread is all the richer for your profound contributions. :tongue:
    Last edited: Nov 18, 2007
  19. Nov 19, 2007 #18
    And for your childish sarcasm.
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