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Many Worlds and Personal Immortality

  1. Jan 11, 2005 #1
    "Many Worlds" and Personal Immortality

    Let's say that the "many worlds" interpretation of quantum theory is correct. Let's also say that there is no afterlife, and that at death consciousness would simply end.

    So no one will ever experience anything after death. From the timeline of any person's consciousness, the period after death is simply an impossibility.

    Therefore my consciousness will--and can--always choose a path through the "many worlds" universe where I do not die. So I am immortal. Even though much evidence indicates that people die, these people who die are not conscious beings _within my consciousness timeline_. From my perspective there is no sound reason to believe they are conscious. Indeed, the fact that they die is evidence that they are _not_ conscious.

    If consciousness other than mine does exist, it must obey the same rule, and never die. Therefore it will probably take a different path through the many worlds. If other conscious beings are present in my world right now, most likely they will eventually take a divergent world, undetectably, leaving behind an no-longer-inhabited simalcrum which acts just like they did.
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  3. Jan 12, 2005 #2


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    This is very interesting! It reminds me of quantum leap, except that consciousness goes to a different universe rather than a different time. Who knows if this isn't what happens every time we wake up in the morning...

    From this perspective though, what would you say about your consciousness time line between when you fall asleep, and when you wake (let's ignore dreaming for the moment)? Would you say that that period of time did not exist?
  4. Jan 12, 2005 #3
    Well, perhaps you are conscious even in non-dreaming sleep, but just never file the experience to memory.
  5. Jan 12, 2005 #4


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    The problem I have with the many worlds interpretation is that it seems to be a form of solipsism. We're each the only real person in our particular universe, at least with astronomically high likelihood. We each weave through our own timelines and probably never meet another real person. That is, unless all of the copies of us in every world are also conscious, which would go against your conclusion here.

    And one other thing. Say your body is riddled with cancer, and you're dying a slow painful death. By your argument, you'd never die, but there's also no reason why the pain would ever go away. Would you want that, to live forever in agony? I'd hate to think the people I loved that died of diseases like cancer are going through that as I speak in an alternate universe.
    Last edited: Jan 12, 2005
  6. Jan 12, 2005 #5
    so what if there is only one consciousness in all the many worlds and we tap into it , project it on to our universe, then return to it when we die...

    ...and if this consciousness is a realm of pure thought where we can manipulate reality like in our dreams then why would we want to return to a 4d existence in any universe

    that would make our lives here just subjective interpretations by an individual entity trying to accomodate the primordial consciousness like a game of "this is what it is like to experience consciousness in a 4d existence on planet earth as a human" 13.7 bilion years after the game began"
  7. Jan 12, 2005 #6


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    I'm with you so far.

    Not sure exactly what you mean here. Sure, given the conditions you've stipulated, it's impossible to experience anything after death. From the point of view of any particular person, existence blinks out at the point of death.

    This doesn't imply that it's impossible for any particular universe to continue existing after a person's death on any particular timeline, though, if that's what you're trying to say. You can only say that if you explicitly assume that objective reality depends on one particular consciousness in some way for its existence. That is surely a counterintuitive proposal, especially if we resonably assume that the universe in question houses more than one conscious being.

    This doesn't follow from the previous statement. You're assuming something like a singular consciousness that hops around from particular universe to universe at each bifurcation point where a given universe splits into its 'many world' offspring. But that would mean that, of all your many world twins, you are the only one who happens to be conscious. The others all look, behave, think, etc. exactly like you, but for some reason, you happen to be conscious and the others are not.

    If we hold the more reasonable assumption that each of your many world twins has his own independent consciousness, then your proposition fails. Suppose you have a many worlds twin who has just suddenly died a second ago. Ex hypothesi, he was conscious but now he is not. You are conscious right now, but your consciousness is distinct from his, just as your body is distinct from his. There is no reason to think that your consciousness right now is a continuation of his, anymore than there is any reason to think that your body right now is a continuation of his.

    Even if I grant you your above claim, this does not follow. To establish this claim, you would have to assume that

    a) your consciousness can hop backwards in time across universes as well as forwards, or
    b) there is at least one incarnation of yourself in one of the many worlds who never suffers a physical death.

    Of these, only a) is remotely plausible. But if we accept a), now we have to reconsider exactly what you mean by 'consciousness.' Suppose that just before the death of your longest living other worldly twin (call him X), his consciousness hops into a universe where one of your twins is a 5 year old (call him Y). Clearly this is a massively discontinuous jump. There is no sense in which any of X's identity or sense of self or experiential content survives. At most, what survives is some sense of experiential awareness, in the most general and abstract sense. The vast majority of what X considers to be himself dies at his physical death.
    Last edited: Jan 12, 2005
  8. Jan 12, 2005 #7
    Why does that mean that? Could it be that all twins share the same consciousness?

    (Twins is perhaps a poor choice of vocabulary. I see how bifurcation leads to the word "twin" but since there are up to 2^n worlds, where n is the age of the universe in seconds divided by ~10^-43, or perhaps more if the base is not 2. Therefore, it should be called 2^n-tuplets or some such. Ok, let's forget that and stick to twins, knowing that there might be a lot of twins.)

    To throw some plausibility into the positivity of the answer to the last question, albeit slight, I suggest/propose that when we dream at night, we are seeing through the eyes of a twin in a different universe.

    I can see though how occam's razor slices that theory to pieces by the simpler theory that there is one universe and dreams are just a natural by product of our physical cranial activities although not, as yet, understood fully. It is perhaps more complex to suggest that:
    1. when we are awake we can only focus on our universe (this benefits our survival as we would be distracted from our prey and predators chasing us if we could peer into other universes while awake)
    2. when we are asleep, we distraction is not an issue so we are free to roam different universes. the connection is that all twins share the same consciousness. This would imply that perhaps in your twin's sleep, he is dreaming what you are doing right now.

    This theory also raises the question of consciousness. Why is it not trapped in one universe like the rest of things (like matter and energy)?

    So, again, occam's razor to me suggests that dreams are just products of our subconscious and there is no multiversal travel or parallel experience here.

    In this theory though, in response to the last quoted sentence, all twins are conscious and all twins share the same consciousness like spokes on a wheel. (But then, what is the hub?)

    Even reasonable people disagree on what is reasonable. I would say that it's simpler and therefore more reasonable that each of my twins shares my consciousness but that you and I have different consciousnesses. Kind of like equivalence classes in math: the is one class of all twins with my consciousness and another class of all twins with your consciousness, and so on.

    Therefore, in this theory, each class of consciousness persists beyond the death of individual members of that class unless all members of the class, all twins of someone, dies, in which case who knows what happens?

    Or assume that
    a') your consciousness already is across universes, manifesting in all twins simultaneously

    b) is also remotely plausible. There might be 2^n universes out there. I will grant that immortality is unlikely, but does it have probability 0? How do you know that? Even if it's astronomically unlikely, given that 2^n is astronomically big, I think that makes it PLAUSIBLE. I'm not claiming it's certain though. That is, unless the probability of immortality, that a twin is immortal, is 0 which is not clearly a plausible assumption.
  9. Jan 12, 2005 #8
    I'm not necessarily saying there is only 1 version of your consciousness. Presumably there would be an infinite number of paths which do not involve your death, and in all of those you could be conscious.

    On further thought, working on the above, I think that all people in any given consciousness' world could be conscious. The other consciousnesses would only have to diverge an instant before their death in your world--so when the other consciousnesses go on living along another path, they leave a dead body behind, not an automaton.

    This is NOT so! From the point of view of any particular person, there _is_ no death. The "blinking out" is a non-experience, since it would have to involve the perception of non-perception, which is an impossibility. So the "blinking out" will never happen to anybody.

    Think of this: as your experience progresses, even when you do not die, there are an infinite number of paths through spacetime which exit your head and thus constitute non-experience (as, hypothetically, the air around you is not conscious). You never follow any of those paths, simply because they are non-experience. Why then would you suppose to follow a path which leads to non-experience through the alternate means of death? It's inconsistent.

    This is exactly what I'm saying. There are an infinite number of such incarnations. All probabilities in quantum theory are nonzero, so in the "many worlds" interpretation, every possible path is taken, including those in which I never die.
  10. Jan 14, 2005 #9
    The base will be vastly more than 2. Each particle has a nonzero probability of being anywhere in the universe--so how many positions is that? The base will be approximately the number of positions per particle to the power of the number of particles--a gigantic number. The number of possibilities increases by that factor every ~10^-43 seconds, as you said. It's effectively infinite.
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