Monday, September 21, 2009

Why 'Quantum Immortality' is false

In the previous posts, I explained that effective 'probabilities' in an MWI are proportional to the amount (measure) of consciousness that sees the various outcomes. Because this measure need not be a conserved quantity, this can lead to nonclassical selection effects, with 'probabilities' for a given outcome still changing as a function of time even after the outcomes have been observed and recorded. That can lead to an illusion of nonlocality, which can only be properly understood by thinking in terms of the measures directly, as opposed to thinking only in terms of 'probabilities'.

The most extreme example in which it is crucial to think in terms of the measures, rather than 'probabilities' only, is the so-called 'Quantum Suicide' (QS) experiment. Failure to realize this leads to a literally dangerous misunderstanding. The issue is explained at length in my eprint "Many-Worlds Interpretations Can Not Imply 'Quantum Immortality'".

The idea of QS is as follows: Suppose Bob plays Russian Roulette, but instead of using a classical revolver chamber to determine if he lives or dies, he uses a quantum process. In the MWI, there will be branches in which he lives, and branches in which he dies. The QS fallacy is that, as far as he is concerned, he will simply find himself to survive with no ill effects, and that the experiment is therefore harmless to him.

A common variation is for him to arrange a bet, such that he gets rich in the surviving branches only, which would thus seem to benefit him. Of course in the branches where he does not survive, his friends will be upset, and this is often cited as the main reason for not doing the experiment.

That it is a fallacy can be seen in several ways. Most basically, the removal of copies of Bob in some branches does nothing to benefit the copies in the surviving branches; they would have existed anyway. Their measure is no larger than it would have been without the QS - no extra consciousness magically flows into the surviving branches, while the measure in the dead branches is removed. If our utility function states that more human life is a good thing, then clearly the overall measure reduction is bad, just as killing your twin would be bad in a classical case.

It is true that the effective probability (conditional on Bob making an observation after the QS event) of the surviving branches becomes 1. That is what creates the QS confusion; in fact, it leads to the fallacy of "Quantum Immortality" - the belief that since there are some branches in which you will always survive, then for practical purposes you are immortal.

But such a conditional effective probability being 1 is not at all the same as saying that the probability that Bob will survive is 1. Effective probability is simply a ratio of measures, and while it often plays the role we would expect a probability to play, this is not a case in which such an assumption is justified.

We can get at what does correspond for practical purposes to the concept of 'the probability that Bob will survive' in a few equivalent ways. In a case of causal differentiation, it is simple: the fraction of copies that survive is the probability we want, since the initial copy of Bob is effectively a randomly chosen one.

A more general argument is as follows: Suppose Bob makes an observation at 12:00, has a 50% chance QS at 12:30, and his surviving copies make an observation at 1:00. Given that Bob is observing at either 12:00 or 1:00, what is the effective probability that it is 12:00? (Perhaps he forgets the time, and wants to guess it in advance of looking at a clock, so that the Reflection Argument can be used here.) The answer is the measure ratio of observations at 12:00 to the total at both times, which is therefore 2/3.

That is just what we would expect if Bob had a 50% chance to survive the QS: Since there are twice as many copies at 12:00 compared to 1:00, he is twice as likely to make the observation at 12:00.

Most of your observations will be made in the span of your normal lifetime. Thus QI is a fallacy; for practical purposes, people are just as mortal in the MWI as in classical models.

In fact, there is a general argument to be made against immortality, which applies to immortality of any sort: If we were immortal (or very long-lived), then the effective probability of making an observation before we are older than a normal human lifetime would be zero (or very small). Since we find ourselves within a normal human lifetime, we can rule out immortality in favor of the competing hypothesis which assigns a high probability to such 'normal' observations, namely mortality.

Next up: Early attempts to derive the Born Rule in the MWI

45 comments:

  1. Very interesting post, but I am left with one question: do observers experience death?
    If not noone really "dies" in MWI?
    Sure the amount of living copies would be lower if you got into a guaranteed death scenario such as jumping out of a plane without a parachute, but there would be that atleast 1 survivor in MWI.

    Did the other's really die just like in a single universe?
    Wouldn't this require that you could somehow experience death?

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  2. Hello, qpdb. Thanks for your comments. I wonder, how did you come across the blog?

    As for your questions:

    > do observers experience death?

    If you mean do they experience being dead, the answer is of course NO. But if they are dead, then they no longer experience being alive, either.

    > If not noone really "dies" in MWI?

    Wrong. As I explained above. See the eprint for a more detailed explanation. I honestly don't know why people keep making that mistake even after I've explained it.

    > Sure the amount of living copies would be lower if you got into a guaranteed death scenario such as jumping out of a plane without a parachute, but there would be that atleast 1 survivor in MWI.

    Absolutely. There is always a tail of decreasing measure. In QM that is true in space as well as in time. There is a bit of your wavefunction that will tunnel to the moon today. Does that mean you will definitely go to the moon today? If not - and of course it is not - there is no more reason to think that you will eventually go to the far future than there is to think you will go to the moon today. Most of your measure is localized on Earth - and is localized in time.

    > Did the other's really die just like in a single universe?

    Yes, for all practical purposes. Definitions of 'persons' are arbitrary but once we have a useful one and we stick to it, yes.

    > Wouldn't this require that you could somehow experience death?

    Absolutely not.

    Hope that clears up any confusion, but you should probably read the eprint.

    Jack

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  3. Thanks for your answers.
    I came across this blogg when I googled something like "quantum immortality + false"

    I took a look at the eprint, but this is still creating some dissonance in my mind.

    If MWI had been true then 00:00 am today I am sitting in this chair and there is a nonzero probability that my chair will spontaneously becoe a bomb and kill me at 00:01 am, now you say "well yes, but that is only a incredibly tiny part of your measure", sure ut it would still be the 00:00 am me experiencing it, so I don't see why the probability even matters here.

    Like you say, you cannot experience death, and I am both the person exploding and not exploding, but I can only *be* the person surviving since dying is a non-experience...

    In the single universe if you die, you infact DIE.
    There is no splitting that causes one consciousness to never end.

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  4. I have been thinking more about this topic in the last days and I still reach the same conclusion... If MWI had been true, I fail to see how *you* would ever *die*.

    At the "death moment", right before the split, the person is you, then the splitting takes place and instantly after the split, there is a alive person in one branch and a dead body in the other branch.
    But there was never a conscious being that died since you are obviously not conscious while dead.

    In a single universe death is actual, the consciousness ceases to be.
    In MWI there is no "death" taking place, after the split there is just a lifeless body that never had life...

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  5. qpdb wrote:

    > right before the split, the person is you

    A big part of your problem is probably right there. You are using the singular tense. It would be more accurate to think there are always "many people" in the category that we will lump into "qpdb" for example.

    How do you think of an ordinary MWI "splitting" in which two different outcomes are both seen? Do you think of it as new people being created? If so, a great majority of people would be around at the oldest times; how do you explain the fact that the statistical expectations of such an effect are not observed by us?

    I am hoping these questions can lead you to understand what measure of consciousness means and why it's important.

    > then the splitting takes place and instantly after the split, there is a alive person in one branch and a dead body in the other branch.

    When that happens, measure of consciousness decreases. In your own words, can you define what that means?

    Don't just say that "the number of copies decreases" because that's not a definition of measure; I like to assume that measure *is* proportional to number of copies, but for example dualist hypotheses about mind could well violate that assumption.

    > But there was never a conscious being that died since you are obviously not conscious while dead.

    Huh? Some kind of word game there? That much is equally true in a single-world model.

    > In MWI there is no "death" taking place,

    Sure there is. Just because there are survivors doesn't mean there aren't die-ers too.

    > after the split there is just a lifeless body that never had life...

    No clue why you say that since it is obviously false.

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  6. Mallah said:

    >A big part of your problem is probably right >there. You are using the singular tense. It >would be more accurate to think there are >always "many people" in the category that we >will lump into "qpdb" for example.

    Well I know Deutsch holds this view that there are a infinite number of pre-existing seperate, yet not seperate but fungible worlds.
    Is this your view too?
    I was under the impression that the majority of MWI proponents argued that before the split, there is 1 world, then after there are more?


    >How do you think of an ordinary MWI "splitting" >in which two different outcomes are both seen? >Do you think of it as new people being created? >If so, a great majority of people would be >around at the oldest times; how do you explain >the fact that the statistical expectations of >such an effect are not observed by us?

    Well I do not believe in Many Worlds, so I would say it's an argument against MWI if anything...


    >When that happens, measure of consciousness >decreases. In your own words, can you define >what that means?

    Well assuming MWI I imagine that it means that given a certain situation one can increase or decrease the number of decsendants.
    But for this argument the number is 100% irrelevant.

    >Don't just say that "the number of copies >decreases" because that's not a definition of >measure; I like to assume that measure *is* >proportional to number of copies, but for >example dualist hypotheses about mind could >well violate that assumption.

    I am not sure what else you would want me to say?
    i agree that dualism is wrong, I hold the materialistic and functionalist view of mind.



    >> In MWI there is no "death" taking place,

    >Sure there is. Just because there are survivors >doesn't mean there aren't die-ers too.

    Well the dier was never conscious...
    If *you* personally right now put a gun to your head and shot yourself, the only way you would not die would be if magically the bullet turned into some non-lethal substance or something similarily improbable.
    So obviously in the vast, vast majority of branches you "die" and this is the very crux of the matter...
    For simplicity's sake let's say there are only two outcomes, one branch in which you die and one in which you live.
    Pre-shooting there is one conscious Mallah, after the shooting there is also only 1 conscious Mallah and one dead obviously unconscious Mallah, but this dead and unconscious Mallah was never conscious in his branch to begin with, the only living person is in the surviving branch?
    It's not like this dead Mallah was isolated on one branch up until his death as would be the case in a single universe where *YOU' actually *DIE* personally...

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  7. Oops, I wrote > infront of every sentence I quoted in the commentary field without thinking about how size of the site.

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  8. qpdb wrote:

    > I was under the impression that the majority of MWI proponents argued that before the split, there is 1 world, then after there are more?

    The 'number of worlds' is not a particularly meaningful concept. What matters are the observers. There are always either a large number or a continuum of observers (depending on details of the interpretation which are not relevant here).

    [re: ordinary splitting & "observer creation"]

    > Well I do not believe in Many Worlds, so I would say it's an argument against MWI if anything...

    It isn't. You didn't really try to answer my question, so I don't think we can get much further as you are not putting any serious thought into it.

    The answer has everything to do with the fact that in an ordinary splitting, the total measure remains the same. Also, there is no real definition of "new people" vs "the same person" and personal identity is irrelevant to anything; measure is what matters. All of this is explained in my eprint.

    At the least, I hope you realize that if you don't understand how the MWI would work even in ordinary cases, you are certainly in no position to evaluate whether QI would work in it.

    > It's not like this dead Mallah was isolated on one branch up until his death as would be the case in a single universe where *YOU' actually *DIE* personally...

    Wrong, it is exactly like that, at least FAPP.

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  9. Jack wrote:

    >It isn't. You didn't really try to answer my question, so I don't think we can get much further as you are not putting any serious thought into it.

    I do put serioust thought into it, but my honest opinion is that MWI in it's current "splitting form" is wrong, but even if I play Devil's Advocate I am not sure if I understand your question.

    You are suggesting that if Quantum Immortality was true then you should expect to be 1 billion years old or something, but why?
    you would be spread out more in your "younger years" and thus it would higher probability for you being young than old?


    >The answer has everything to do with the fact that in an ordinary splitting, the total measure remains the same. Also, there is no real definition of "new people" vs "the same person" and personal identity is irrelevant to anything; measure is what matters. All of this is explained in my eprint.

    I disagree and this is why, let's remove all the additional mysterious talk about worlds and simply talk of a amoeba.
    If it always divides into 2 when faced with a life and death situation , it goes on living and the other part of it just ended up dead after dividing.
    But then that specific divded part never had life!
    Before dividing it was a living amoeba, after dividing it is still living on and the other "part of it" just ended up as dead material, but this dead material was never living...


    >Wrong, it is exactly like that, at least FAPP.

    FAPP is too vague, it doesn't matter if your family and friends grieve at a funeral and percieve your dead body as you dying if infact your subjective experience goes on living, as that is the only real life there is.
    Right now (assuming MWI) you could kill yourself easily in such a manner that only a miraculously improbable event could stop it from happening, which obviously would have to occur had MWI been true, now you explain me how would your subjective experience end if there is always atleast 1 branch in which you continue you percieve?

    How do the exact Mallah I am talking to now die when he also is going to live, unless you postulate some sort of soul that only follows one branch and dies?

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  10. qpdb wrote:
    > You are suggesting that if Quantum Immortality was true then you should expect to be 1 billion years old or something, but why?

    Immortality would mean that most of your life would be in the much older than normal period. Not seeing that (and we don't) would be very atypical.

    > you would be spread out more in your "younger years" and thus it would higher probability for you being young than old?

    I don't know what you mean by "spread out more".

    > let's remove all the additional mysterious talk about worlds and simply talk of a amoeba.

    OK, let's talk about an amoeba. In ordinary amoeba division, you start out with 1 of them and end up with 2 of them. That is a measure-doubling process (assuming that an amoeba has measure), which is extremely different from the quantum mechanical case of "world-splitting" in which the total measure remains the same.

    Of course, after 1000 amoeba doublings, there would be 2^1000 amoebas. Surely you see that a typical "amoeba observation" would in this case - UNLIKE in the quantum case - be in a late generation. It would be very unusual for an amoeba to find itself in an early generation, though a few (of course) would. And we know that the quantum case can not be like this.

    > If it always divides into 2 when faced with a life and death situation , it goes on living and the other part of it just ended up dead after dividing.

    Now, if we start out with 1 amoeba and end up with 1, that is a process in which measure _does not change_ - quite different from the QS case in which measure decreases.

    The amoeba analogue to the QS case would be starting out with 2N amoebas and killing N of them, leaving just N to remain alive. That is a measure-destroying process like QS.

    > FAPP is too vague, it doesn't matter if your family and friends grieve ...

    That has nothing to do with what I was talking about and I'm surprised you would even suspect that I might have meant such a thing.

    To be clear: When I say it's like that FAPP, I mean from the point of view of those undergoing the "QS".

    > now you explain me how would your subjective experience end if there is always atleast 1 branch in which you continue you percieve?

    There are many "you's". Then half of them are gone. Those half no longer perceive.

    > How do the exact Mallah I am talking to now die when he also is going to live, unless you postulate some sort of soul that only follows one branch and dies?

    If he dies, then the guy that lives is some other guy who happens to share characteristics with him.

    I think it is best (less confusing) though to consider a "person" as just an observer-moment. So the guy you are now is, by this definition, a different guy than you were a second ago. This definition evades the need to define what makes a person the same over time, for which there is no natural or non-arbitrary definition (so certainly no such definition could affect predictions or decision-making despite what you might think at first).

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  11. I still fail to recognize how one of these observer moments would also become a "dead moment" before splitting, if that is impossible, then I don't think you can't say that a conscious person died...

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  12. An observer-moment is an observer at a moment in time. It doesn't "become" anything as any change would bring in a new moment.

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  13. Obviously..

    But that is my point if you got a person in a certain observer moment and afterwards you got a observer in another observermoment and a dead person in a nonobserving moment, then he never died.

    It is very hard to explain this for some reason....
    And I am not sure what analogy I can use to get my point across.

    The fact that most MWI sympathizers seem to hold the position that I do (while playing devils advocate) seems to suggest that you are missing something.


    In a single universe the very observer that ends up being dead, doen't live on in any branch.

    If you believe in MWI, you don't get away from the fact that the oberver will always survive.
    The fact that a dead body ends up in a branch doesn't matter ,it was never alive.

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  14. qpdb wrote:
    > But that is my point

    Existing only for a moment is not being immortal, so if you did have some kind of a point, that clearly wasn't it.

    > if you got a person in a certain observer moment and afterwards you got a observer in another observer moment and a dead person in a nonobserving moment, then he never died.

    In the QS case you have (in effect) 2N people at the first moment and N people at the second moment. That is equivalent to saying that half of the original people died. It's the same thing FAPP.

    You seem to understand how _measure distributions_ work as a function of spatial location, so why can't you understand that they work the same as a function of time?

    And obviously, even in a single universe, there is a dead body after a guy dies. You could say that the body was never alive - as it's at a different moment than the live guy was. Pretty meaningless to say that though.

    > It is very hard to explain this for some reason....

    Given that you are in error, it's not surprising that you find your position hard to explain.

    > The fact that most MWI sympathizers seem to hold the position that I do (while playing devils advocate) seems to suggest that you are missing something.

    Ah, an appeal to the authority of the masses. Funny, I didn't take you for the kind of guy who takes his cues from the masses. So does the fact that most MWI sympathizers think that the Born Rule has been successfully derived "suggest that" the MWI has no problem with that?

    Besides, I am not convinced that most do agree with the QS idea. The one who do are more vocal. Even if it's true that most do, that is probably due to the fact that there have been media articles (mainly from Tegmark) promoting the idea. I can see that I should do more to publicize my own work.

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  15. I am not sure if we will ever come to an agreement, but I AM TRYING.

    You are correct, I am not the sort of person that "appeal to majority", I brought it up to show that obviously my thinking not some fringe stance, there must be something we (the majority) then are missing.

    Pretend that this (below) represents the splitting:

    -<

    First you have a straight line representing one observer, then it splits: dead and alive.
    Pre-split there is 1 observer, post-split, there is 1 observer.
    Which observer died?

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  16. One more try, then.

    Your diagram is misleading. It is the amoeba example all over again.

    There are always many observers, NOT one, both before and after the split.

    As I recently argued in the amoeba post, it simply can not be true that an ordinary (non-deadly) split doubles the number of observers; instead the number doesn't change in the ordinary case. In the QS case, then, the number of remaining observers is halved. You would better draw the following diagram:

    =<

    Until you take this into account, you will not get anywhere.

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  17. Ok let me get this straight, you are implying that the worlds are pre-existing entities all along?

    If MWI had been true there would be an infinite number of identical worlds with identical pasts in parallel to this one?
    So the "split" is nothing more than differentiating of the worlds, changes happening isolated within each branch?

    so there is no real splitting of 1 person into 2 in example given above?

    This is in strong contrast to the MWI that Tegmark and Wallace argues for...

    Wouldn't it require an additional variable, why would X happen in world 1 and Y happen in world 2 if they are identical and there is no splitting induced by decoherence?

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  18. A "world" is not a well-defined concept in the MWI (nor does it need to be). Counting "worlds" is like counting waves - actually it _is_ counting waves - you might see three distinct wave crests approaching a beach, but if you look more closely there are no doubt many smaller waves among them and there is no exact place that one ends and another begins.

    This can be confusing at first, especially since people often talk about worlds when describing the MWI. Which is a perfectly reasonable thing to do. Imagine if you are trying to describe a situation in which a water wave encounters a rock and part of it gets reflected back while part of it goes around the rock and continues on. Would you say that the wave split in two? Probably you would. Would saying that commit you to the view that there _was actually_ "one wave" before the rock was encountered and "two waves" afterwards? Of course not - waves aren't something you can give an exact count of.

    What does need to be counted precisely are not worlds but observers. (As you know if you've been reading the blog, I generally assume that observers are implementations of computations, and I call my approach the Many Computations Interpretation.)

    The details do not matter for the issue at hand - what does matter is the way the amount of consciousness (which for now we can assume is proportional to the number of observer-moments) which sees each kind of observation, behaves in the various situations over time, or in other words, what matters is the measure distribution.

    So are any of the _observers_ before an event the same as the ones afterwards? On the observer-moment definition, that is by definition not the case. There are other definitions and details of the interpretation can come into play. For example, in Continuum Bohmian Mechanics (a many-worlds form of the PWI), you could say (within limits) that the observer implemented by a given set of the hidden variables was the same over time. In the standard MWI physics but with a computationalist view, it's not clear to what extent you could trace computations extended over time.

    But even in purely classical mechanics there is no exact definition of an observer being the same over time. You could replace a person's neurons one at a time, while using the old neurons to produce a new brain in a similar configuration to the old brain. At the end you have two similar brains. Which is the original guy?

    None of this matters even a little! The only thing that matters is the measure distribution. That is always well-defined given the situation and does not depend on arbitrary definitions.

    What we can say for certain is that in an ordinary split total measure (or total number of observers if you prefer to think of it that way) remains the same, while in a QS split it decreases.

    Oh, BTW, did I mention that the measure distribution is what matters? I might have said that, somewhere, once or twice ...

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  19. The vaguness of "worlds" does not help.
    Infact Miroljubs paper show why MWI is falsified even if one tries to hide behind vague statements about "no definite point that seperates a dead you from a live you".
    You should really check the paper...

    Back to immortality, I agree that none of all of that REALLY matters in this debate.
    But I'd like to give you a simpler analogy.

    Say I had a machine, once you steped into it, it instantly took apart your entire body and recreated it perfectly, but it created 2 "you's", who is the original? Neither or both is the only sensible answer.
    Obviously since the machine uses one version of you to create two yous it means the size of the two yous are half of what they were before stepping into the machine.

    However once you step into this machine, it creates a perfect you living and well and use the other particles to create a replica, but a dead one which by definition *NEVER* had life...

    That is what it all boils down it, it doesnt matter if you live in 1 branch or 10^24124124214124121 branches.
    The only thing that ever mattered in this debate is whether the dead person ever had life, if not, you are infact immortal if MWI is true.

    Just like my replica machine example, for everyone else the dead body copy o you would seem like you actually died, but the truth is that "you" was never a living being...

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  20. qpdb wrote:
    > Infact Miroljubs paper show ...

    Not so, but I'll discuss it in the "MWI proposals" thread, not here.

    > Say I had a machine, once you steped into it, it instantly took apart your entire body and recreated it perfectly, but it created 2 "you's", who is the original? Neither or both is the only sensible answer.

    For once we can agree on something.

    > Obviously since the machine uses one version of you to create two yous it means the size of the two yous are half of what they were before stepping into the machine.

    Size? What do you mean by that?

    I'm guessing that what you were trying to say is that the measure of each of the 'after' guys is half of that of the 'before' guy. That is FALSE.

    If an 'after' guy is physically similar to a 'before' guy, then his measure would be the same. Since there are two of them, the machine DOUBLES the total measure. What you have described is, once again, no different from the amoeba example which I have explained to you more than once already.

    The QM case is very different because measure is not changed in an ordinary (non-deadly) "branching". Of course that means that in this case an 'after' guy must be _physically different_ from a 'before' guy, and the way in which he is different is that the squared amplitude of his wavefunction is less - that's the Born Rule. This is not the place to discuss the derivation of the Born Rule, but suffice it to say that in my MCI, fewer computations (observers) would be implemented by smaller branches.

    BTW, if the total squared amplitude of the wavefunction could change over time, then presumably the total measure would change over time - the fact that is does not is an observed law of physics, not something we could have assumed on philosophical grounds.

    > The only thing that ever mattered in this debate is whether the dead person ever had life,

    No, that is totally irrelevant. Suppose that in your machine the 2nd copy was alive for one minute, then killed, leaving one copy alive. One is the same number of guys you started with, so FAPP, the machine does nothing - the guy FAPP survives it despite the fact that the dead body was once very much alive.

    Back to the one thing that does matter: In the QS case, the number (measure) of surviving observers is half of the number (measure) of original observers, so FAPP it's like a single-universe case with a 50% chance of death.

    Until you take the decrease in measure into account, you will not get anywhere.

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  21. Ok this is NOT what I was trying to get across AT ALL.
    When I said "obviously the two are smaller" I was just referring to the fact that in this classical example you would have to create miniatyr copies of a person to get 2 persons out of the amount of atoms in one person, otherwise you would have to get the energy from somewhere else, it was not a statement regarding measure at all...

    You are still missing the crux, let's go back to the machine (yes it is very similar to the amobea example, but it is more intuitive and paints the picture more clearly:

    You go into the machine, at this point there is ONE Mallah, now the machine takes this energy and creates 2 of you, one alive and one dead, how was the dead ever alive? if he was never alive, he can by definition never have DIED...

    I don't understand why this is so hard for you to grasp...
    If you shoot yourself in the head right now, why do YOU die if a copy survives and all the dead outcomes never had life in their branch?

    The measure itself does not matter really, sure it matters in the sense that "we should try to optimize the amount of copies of ourselves if we care about life and so on yadayada, but noone cares about that in this debate. because it is not relevant AT ALL!

    You could just as easily say the same about the machine dead guy, "but he was created from a living being!" sure, but *HE* was never alive...

    Explain exactly how you DIE if MWI is right, how do YOU die? How do you cease to experience reality when you are guaranteed to show up in one branch ?

    Everyone else seems to hold the position I hold, so it must be something you are missing or all of us are missing, but you have still failed to show how the universe somehow splits into 1 alive guy and 1 alive guy who dies before any splitting occurs, because if that is not the case. Then noone died.

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  22. qpdb wrote:
    > When I said "obviously the two are smaller" I was just referring to the fact that in this classical example you would have to create miniatyr copies of a person to get 2 persons out of the amount of atoms in one person,

    Then it's far from a perfect recreation! Usually in such a thought experiment the machine would have a ready supply of appropriate ingredients to assemble.

    >You go into the machine, at this point there is ONE Mallah, now the machine takes this energy and creates 2 of you, one alive and one dead, how was the dead ever alive?

    If THAT is what the machine does, then the dead one was never alive. Which, as I said, is totally irrelevant since if he was alive for a moment then killed then the dead guy WOULD have been alive (but so what?), AND because the QM case is _nothing like_ that machine, as I've explained many times by now.

    > If you shoot yourself in the head right now, why do YOU die if a copy survives

    Because the "copy" isn't me, he's a guy similar to me, who would have existed whether or not I was shot - and if I weren't shot, another similar guy, 'future me', would have existed ALSO. Just because you have a twin brother doesn't mean you can't die unless he does.

    > The measure itself does not matter really, sure it matters in the sense that "we should try to optimize the amount of copies of ourselves if we care about life and so on yadayada, but noone cares about that in this debate. because it is not relevant AT ALL!

    You are 100% wrong. The measure - or number of people - is the only thing that matters. As I've explained. Read the eprint again.

    > Everyone else seems to hold the position I hold,

    Not at all. You are just asking the wrong people. Besides, appealing to the 'wisdom of the masses' is not how science works.

    > you have still failed to show how the universe somehow splits into 1 alive guy and 1 alive guy who dies before any splitting occurs,

    I didn't "fail to show" that because I never wanted to show any such thing. What I DID show was that in the QS case there are initially 2N guys and after the QS there are only N guys remaining, and thus FAPP half of the original guys died.

    qpdb, your replies have been repetitive. I think I have expressed my position clearly enough. If you want to continue this conversation, please do not do so until you have something other to say than another repeat of the amoeba example, because my reply to that will always be the same: the "amoeba split" creates _additional_ guys while the "QM split" _does not_.

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  23. For that matter, since death doesn't occur instantly, it would generally be the case in a QS-type experiment that the split occurs before the death (e.g. for a gun with a 50% chance to fire determined by measuring a quantum event, the event would have caused a 'split' prior to the shooting). But, again, that's not important. The only important thing is what happens to the total number of people (measure) so that's what I've been talking about.

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  24. Yes, I am repetitive, but I am trying to rephrase the argument so that you might get it.

    I don't understand how you can bring up twins as a counter example, twins are seperate entities.

    There seems to have be a discussion of quantum immortality over at lesswrong just a month ago: http://lesswrong.com/lw/87o/a_pessimistic_view_of_quantum_immortality/

    Maybe you should make an entry there explaining why QI is wrong and then maybe you will reach an agreement with a person there instead and maybe through your discussion I will see where I am wrong in this debate (if I am) or the other way around...

    Seeing as I am 99,9% sure that MWI is wrong due to probability, preferred basis and especially M. Dugic's new brilliant paper I do not have to care too much about these issues, but what concerns me is that there seems to be quite a lot of people who have no idea about quantum mechanics who seem to have accepted MWI on no grounds other than the fact that Eliezer yudowsky has advocated it.

    that some of these individuals might attempt a quantum suicide seem inevitable...

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  25. qpdb, I understand the amoeba-type branching fully; it's just that there's nothing about it which supports your position.

    > I don't understand how you can bring up twins as a counter example, twins are seperate entities.

    Twin brothers are separate entities - just exactly the same as the different "copies" of a person are separate entities. Sure, the "copies" have the same experiences as each other, but that's irrelevant. I think from now on I should stop using the term "copies" and instead use "brothers" so maybe people will start to understand what measure of consciousness means.

    How do we know that the copies (or implementations of computations in my MCI) are separate entities? If we assume that the MWI is true - which we will do for the sake of argument as we are trying to see what consequences it would have - it is easy to prove: the Born Rule. If they were not separate, then the number of observers (measure) would be equal for any observable outcome, and the Born Rule could not hold. But we know that the effective probabilities are _not_ in general the same for each outcome. Therefore, if the MWI is true, the "copies" must be separate entities, and there must be more of them in the branches with higher effective probability.

    Hence my talk of 2N guys before the QS and N guys after it. Get it?

    Now, it's true that not every MWI advocate favors the idea of observer-counting to get the probabilities. To that objection I refer to my refutations of other methods.

    > There seems to have be a discussion of quantum immortality over at lesswrong ...
    > Maybe you should make an entry there explaining why QI is wrong ...

    Maybe I should. But as you have noticed, there seems to be a bit of a herd mentality at LW.

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  26. Ok so are you suggesting that the "brothers" are seperate even before the split takes place?
    If so, then yes I see how one end up dying and one end up living.

    But I don't think this is what you are suggesting, as this would remove splitting from MWI, leaving it as some new form of MWI...

    This seems to suggest that all of the universes exist seperately and that outcome A happens in branch A and outcome B happens in branch B, but this would require some sort of new variable causing A to happen in branch A and so on when they are identical up to the moment where they are supposed to split (but no longer if the view is tha tthey are seperate even before the split).
    So let's clear that up first...

    Yes, very few over at LW seem qualified to talk about these matters and most of the people on there talking about MWI only does so because they have accepted Yudowsky as their messiah so whatever he believes, they believe.

    Hell Yudowsky has even admitted to not knowing enough about physics or math to do QM, yet he claims MWI is correct... hilarious, but also sad...

    I personally find it a bit scary seeing tens of people discussing quantum suicide (especially because I know MWI is wrong) like it is something they consider doing in something like quantum suicide lottery.

    Hopefully MWI will die out soon now that more and more arguments against it gets known, otherwise I suspect a huge amount of "creative suicides" in the future.

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  27. qpdb wrote:
    > Ok so are you suggesting that the "brothers" are seperate even before the split takes place?

    What I am saying is that the amount of consciousness (measure) is the sum over them, so yes, they are not the same people as each other. This can be generalized to continuous cases and cases where measure is not a sum per se over observers (as is often done in dualistic models); as long as the essential nature of measure as amount of consciousness is respected, those details make no difference FAPP.

    > this would remove splitting from MWI, leaving it as some new form of MWI...

    Not at all. Splitting in the MWI relates to 'worlds'. I am talking about observers.

    The only assumption I am making is that measure / quantitative amount of consciousness (which is best thought of as the number of observers) is proportional to squared amplitude.

    > This seems to suggest that all of the universes exist seperately and that outcome A happens in branch A and outcome B happens in branch B, but this would require some sort of new variable

    Observers are not the same as "worlds" or "universes". For one thing, if there are no observers around, we can still talk about "worlds". OTOH a "world" might support many observers, as ours clearly does.

    While these details are not needed for refuting QS, in my own MCI, different implementations (of computations/observers, which are counted to get the measure) are based on mappings from different regions in the vast high-dimensional configuration space on which the wavefunction lives. For full details see my MCI eprint:
    http://arxiv.org/abs/0709.0544

    > Hell Yudowsky has even admitted to not knowing enough about physics or math to do QM, yet he claims MWI is correct...

    Well, to be honest, it's so obvious that some sort of MWI must be correct that you don't need a heavy math background to see it. So I can't fault him there.

    > Hopefully MWI will die out soon

    On the contrary, the MWI's popularity is growing.

    > now that more and more arguments against it gets known

    There are no arguments against it that hold any water, with the sole exception of the Born Rule problem, which as you know my work is aimed at dealing with.

    Don't think that just because I haven't got around to demolishing Dugic's argument yet that it's a real issue. I'll address it soon enough.

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  28. I do agree that the rise of belief in QS is scary - it's grown like a cancer in the MWI community - and that's why I spend more time on this thread than on the other one.

    ReplyDelete
  29. >What I am saying is that the amount of consciousness (measure) is the sum over them, so yes, they are not the same people as each other. This can be generalized to continuous cases and cases where measure is not a sum per se over observers (as is often done in dualistic models); as long as the essential nature of measure as amount of consciousness is respected, those details make no difference FAPP.

    This is again whre things get too vague.
    if there is only 1 person before splitting even if his measure is "fatter" than each of the splitted individuals, this does nto matter one bit.

    Either there are seperate universes from the beginning (many bohmian worlds) or you have to accept splitting and the fact that the person who ends up dead never had life.
    A dead person can not experience dying...
    Your obsession with measure is kind of like saying that a person on a McDonalds diet who is severily obese "dies more" than a anorexic person.
    the fact is the amount of observers pre-split and post-split.
    That is _ALL_ that matters when you debate whether or not immortality is a consequence of MWI.


    >Not at all. Splitting in the MWI relates to 'worlds'. I am talking about observers.

    Observers would also have to split, unless you support some sort of many minds interpretation


    >While these details are not needed for refuting QS, in my own MCI, different implementations (of computations/observers, which are counted to get the measure) are based on mappings from different regions in the vast high-dimensional configuration space on which the wavefunction lives. For full details see my MCI eprint:
    http://arxiv.org/abs/0709.0544

    I will take a look

    >Well, to be honest, it's so obvious that some sort of MWI must be correct that you don't need a heavy math background to see it. So I can't fault him there.

    I am afraid you are wrong here, MWI is far from obvious (which can be confirmed if you take a poll in the physics community even Deutsch estimates that less than 5% are proponents of MWI. And it is rejected for good reasons too.


    >On the contrary, the MWI's popularity is growing.

    Not really, amongst sci-fi enthusiasts and people over at LW, sure, but in the physics community people have actually started to abandon MWI.
    Even Weinberg has now rejected MWI which he once supported.

    >There are no arguments against it that hold any water, with the sole exception of the Born Rule problem, which as you know my work is aimed at dealing with.

    Just because you do not grasp them/haven't heard of them does not mean they do not hold water.
    Zurek etc. is trying to solve the preferred basis problem, but it is not solved.
    but even he thinks it will lead to a new nonMWI.

    >Don't think that just because I haven't got around to demolishing Dugic's argument yet that it's a real issue. I'll address it soon enough.

    Ok, he is currently debating the paper with most of the big proponents of MWI, I have yet heard anyone "demolish" it in any way.
    Most have actuall commented on how great it is but that they currently disagree with the conclusion, but thats because the have not checked the math sufficiently.
    Dugic's paper tries to stear clear of philosophical speculation and focus on the math and physics only.

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  30. I also want to point out that assuming that there will be a single universe interpretation that is *the answer* is more likely than assuming MWI.
    To believe in MWI you have to assume that somehow the Born Rule will make sense in MWI, which we know that by following MWI it doesn't.

    This is *not* the case in single universe.

    Every experiment ever conducted in the history of the universe indicates a single universe (yes even double slit where we observe SINGLE particles).

    The "let's hide a multiverse in the gaps" reminds me of creationists and their "god in the gaps" hypothesis.

    You obviously have some deep personal connection with MWI, so I doubt you will ever change your mind, the same goes for people like Tegmark and Deutsch.

    However most physicists do not believe in MWI and the few who do are far from as "confident" in it as you are.

    So while you try to fight against quantum immortality, your faith in MWI is actually detrimental to that cause...

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  31. qpdb wrote:
    > Either there are seperate universes from the beginning (many bohmian worlds) or

    So I take it that you do accept that in the many-worlds version of the PWI the QS idea would be false. That is significant progress.

    > Your obsession with measure is kind of like saying that a person on a McDonalds diet who is severily obese "dies more" than a anorexic person.

    Just how is his obesity similar to measure in any way? Does it affect the effective probability for his observations? Of course it doesn't. Your comparison is ridiculous and shows that you don't understand the concept of measure.

    Measure is the number of observers, or more generally, a generalization of that which has all of the properties of such an amount of consciousness. If something _doesn't_ have ALL of the relevant properties just like the number of observers does, than that thing _isn't_ measure, by definition.

    Perhaps what you really believe is that measure _must_ be proportional to the number of observers; that there is _no other thing_ that _could_ have all of the relevant properties.

    Well, perhaps you'd be right in that - and my own MCI proposals assume that it IS proportional the number of implemented computational observers.

    But that's not the issue here, and not everyone believes in observer-counting. In particular, as I said, most dualists would not. By using abstract measure in place of explicitly saying "number of observers", my anti-QS argument goes through regardless of such details; it is fully general.

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  32. > MWI is far from obvious (which can be confirmed if you take a poll in the physics community

    Most people who don't accept it don't give it a fair hearing because they follow the herd. Remember, it wasn't long ago that the physics community thought that "shut up and calculate" was the only acceptable view of QM. It's also hard to give the MWI a fair hearing because starting to believe it would change someone's world view more than most people are comfortable with. I think that people without such emotional constraints often find that the MWI is very plausible.

    > [Dugic] is currently debating the paper with most of the big proponents of MWI, I have yet heard anyone "demolish" it in any way.

    I would like to read such a debate - it sounds quite amusing. Where is such a thing going on? I wonder who the "big" MWI proponents are ...

    If the paper is getting as much attention as you say, then maybe I ought to write a more formal refutation of it, just to get my name out there a little more.

    > To believe in MWI you have to assume that somehow the Born Rule will make sense in MWI

    Right - the Born Rule is the one issue with the MWI. I don't deny it; it's a real issue and so I mention it a lot; I never try to sweep a real issue under the rug - that would not be the way to advance science. I refer you to my MCI paper for my approach to it. But as I said, the generalized MWI idea is still in a much better position than any other idea.

    > You obviously have some deep personal connection with MWI, so I doubt you will ever change your mind

    Now you are crossing a line with a personal attack like that. I will not tolerate too much of that on my blog.

    If I had reason to believe that some other interpretation was more likely than the MWI, than I would favor that other interpretation. But it's just not the case.

    There are certainly variations on the MWI idea, and I'm open to accepting modifications to it - indeed I expect some - but the only other alternatives are either wavefunction collapse (which is messy, and has many problems of its own) or hidden variables (which is ruled out by the fact that the 'other' branches should still give rise to observers).

    You can try to take comfort in the fact that we don't know how quantum gravity will work, but it's already clear that whatever QG adds to the mix may well _favor_ one of these basic ideas (collapse, MWI, or hidden variables) but can not introduce any radically different alternative to these three. And existing ideas about QG - such as string theory - have shed no light on interpretation of QM. There's no evidence that it ever will.

    > So while you try to fight against quantum immortality, your faith in MWI is actually detrimental to that cause...

    You can't hold back science. Belief in the MWI will win because of the MWI's advantages, not because of any politics or biases, which only can delay science, not stop it. The MWI is here to stay, it will certainly be more popular in the future whether we like it or not, and the only long term way to fight the QS fallacy is by showing that the MWI does not imply it - which I have done.

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  33. No need to write an entire paper if you can falsify his conclusions as simple as you say, just tell him where he is wrong and if you are right he will accept this...
    I can tell him to contact you if you want?

    I will not disclose who he is talking to on a public fora like this, but I think you know who the "biggest" proponents of MWI are.

    He is pure science and does not care about interpretation, he neither favors nor disfavor any of the realist alternatives...
    It's not like he set out to prove MWI wrong, it just so happened it was, as it's other problems have indicated for long.............

    Now, I did in no way, shape or form intend to "attack your persona", but it is quite obvious from the way you write that you are attached to MWI beyond what reality "allows" based on science alone.

    You seem to think that the only options are collapse, MWI or debroglie bohm...
    Well, that is mistaken.

    You also got retrocausal interpretations and a host of other hidden variable interpretations that does not include the wavefunction as ontological at all, so even if your argument that PWI includes MWI (which I disagree with, papers defending this I have shown you) had been correct these give no reason to believe in MWI.

    As for your statements regarding quantum gravity and how it doesn't change a thing, that is quite a weird statement.
    there are several scientists in that field suggesting otherwise.
    Again you are blinded by your FAITH in MWI.

    I definitely do not need some "rewrite of QM" to reject MWI though, I do so on the basis that most other realists do...
    I think it is inevitable that some other hidden variable will give us the answer.
    You are obviously entitled to your own opinion, but please do not preach it as fact...

    I also find it quite weird that you accept that the born rule issue seem to indicate new physics, then you go on to say that this new physics HAS TO give rise to MWI.
    Why the hell would it when everything we have ever observed indicate a single universe?

    Also what about the neutrinos, did you expect them? how do you know how they will affect our models?

    And no I am not trying to hold back science, on the contrary...
    You actually think that the vast majority of physicists who are willing to speculte in all sorts of weird stuff like retrocausality etc. reject MWI because it's weird? Thats preposterous...




    Regarding quantum immortality, just answer this:
    Before the split there is only one Mallah, yes or no?

    If yes: how do ANYONE die when there is only 1 living mallah and one dead body after the split?

    If no: what seperates them?

    Second question: what do you make of tegmark's remarks on quantum immortality that is quoted in the wikipedia article on quantum immortality over at wikipedia?

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  34. qpdb wrote:
    > I can tell [Dugic] to contact you if you want?

    Sure, go ahead. I'll reply to him.

    > You also got retrocausal interpretations and a host of other hidden variable interpretations that does not include the wavefunction as ontological at all

    Not really, but I won't get into it here.

    BTW, for a simple example of MWI vs. retrocausality see the post
    http://onqm.blogspot.com/2009/08/studying-quantum-mechanics-delayed.html

    > everything we have ever observed indicate a single universe?

    No more so than the MWI predicts, and we observe QM effects that suggest the MWI.

    > Also what about the neutrinos, did you expect them? how do you know how they will affect our models?

    I think it's more likely to be an experimental error than FTL, but if it is FTL, there are certainly models that could fit that. Some string-theory inspired models have a 'brane' as our normal space, embedded in a higher-dimensional space, and particles that leave the 'brane' for a short while can go FTL in the 'bulk'; that could explain the lack of Cerenkov radiation.

    > Regarding quantum immortality, just answer this:
    > Before the split there is only one Mallah, yes or no?

    No.

    > If no: what seperates them?

    In my MCI, they are based in different locations in the configuration space on which the wavefunction evolves.

    > Second question: what do you make of tegmark's remarks on quantum immortality that is quoted in the wikipedia article on quantum immortality over at wikipedia?

    I addressed his views in my eprint. It's good to see him arguing against the 'immortality' idea, but it would be better if he understood why QS also fails. If QS didn't fail (which is impossible, but for the sake of argument), then his anti-immortality argument would make sense, yes.

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  35. I'll let Dugic know, he will most likely contact you within the end of the day.

    The criticism you raise seems to be aimed at the retrocausal models by John Cramer and Ruth Kastner, I am talking more along the lines of Huw Price.
    Matt Leifer is also a proponent of this view...

    QM effects does not indicate MWI, thats all interpretational.
    You seem to be a very smart man, but you are very much biased towards this view...

    Regarding the neutrinos, I too was almost 100% sure they were a product of error, but if you have kept up to date you know that the chance of that being the case has become very very small.
    And yes I am aware of different models, but there could be quite a lot of other models that make better sense of it...

    Ok, you say that there is not 1 Mallah before the split, so I take it that your view resembles something like "All universes came into existence at the big bang and they don't split in the traditional Everett-DeWitt way, but rather they differentiate and then we call that "splitting".
    Am I right?

    So before the suicide (if it has 2 outcomes only) there are 2 you's in two seperate worlds that are 100% identical up until the point of experiment taking place, in which they differentiate so in one world you live and in the other you die. Correct?

    My main problem with this view is that it is not very clear to me what causes world 1 to become world A and world 2 to become world B when they are genuinly seperate and identical?
    Since there is no splitting as in Wallace et al. here I just don't see what causes you to die in one branch and live in the other?

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  36. qpdb wrote:
    > I am talking more along the lines of Huw Price.

    He has a neat toy model but that's it. It doesn't seem likely that time evolution would behave like that.

    Other than the Born Rule, the MWI very easily explains all of the apparent 'mysterious' aspects of QM, including Bell's theorem.

    > Regarding the neutrinos, I too was almost 100% sure they were a product of error, but if you have kept up to date you know that the chance of that being the case has become very very small.

    Not necessarily. From what I read, their time resolution is very close to the size of the reported timing anomaly. If their timing is off by one 'tick' - which is a plausible software bug - that could explain the result. In any case, we will find out for sure eventually. I certainly wouldn't mind if it is new physics.

    > Ok, you say that there is not 1 Mallah before the split, so I take it that your view resembles something like "All universes came into existence at the big bang and they don't split in the traditional Everett-DeWitt way, but rather they differentiate and then we call that "splitting". Am I right?

    No, that's not it.

    First, I must again point out the difference between "universes" and "observers". I do not need to speak of "universes" and I have no special definition for them. I am talking about conscious observers - e.g. human minds.

    Next, I must say that you can't necessarily track individual observers over time like that. They are each in different parts of configuration space, but as the wavefunction evolves, "redistricting" them often becomes necessary; soon some parts of configuration space can no longer support as many as before, while other parts can support more than before. That is one reason that it's better to just count observer-moments at any given time; the number of such momentary observers should then obey the Born Rule.

    As for the physics of it, one of my proposals is that there exists just the ordinary wavefunction as in the standard MWI, but that there is a statistically uniform "noise" in the initial conditions for that wavefunction. The effect of this "noise" is to provide a lower limit on the size of a region in configuration space that you need to "lump together" in order to reliably implement a conscious computation with a high enough signal-to-noise ratio. The higher the "signal" amplitude, the more regions can be found with a high enough SNR - so there are more implementations in high-amplitude branches, leading to the Born Rule. See the MCI eprint for more details and other possibilities.

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  37. Are you a dualist? If not, then making a distinction between universes and observers is just flawed from the beginning.

    If there are supposed to be two persons pre-QS there has to be two worlds too!
    And something has to "seperate" them, saying that they are the same person but that it's a bigger measure makes as much sense as my McDonads example.

    The *ONLY* thing that matters is how many DISTINCT observers there are...



    Btw. we've contacted you through mail and look forward to a nice discussion on the paper here.

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  38. Also regarding the neutrinos, have you read the most recent news regarding it (last week) ?
    They have tested for nearly everything...

    I have gone from 99% skeptic to 50-50, it might be like you say a software glitch, but it may also be real.
    If it is real, it'll take some time to figure out what it actually implies...

    If I were to play devils advocate and take your position and say "QM seems to indicate some sort of MWI" then it would be more logical to think "perhaps the born rule is a hint that QM isn't the final word, maybe quantum gravity or new physics will change our view entirely since obviously MWI can not be true due to born rule".

    I applaud your MCI effort and I will take a look at it and pass it around to some of the people I have spoken to regarding probability.
    However you should be more open minded...

    Before discussing the validity of MWI anymore i think you should "demolish" it, like you said.
    Miroljub is excited to see what sort of arguments you will bring forth that he has not rebutted yet.

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  39. qpdb wrote:
    > Are you a dualist? If not, then making a distinction between universes and observers is just flawed from the beginning.

    That assertion is simply false. I assume that observers are implementations of particular kinds of computations. A "universe" may implement many observers. Before life evolved, there were universes, but no observers.

    Multiple implementations are distinct from each other; indeed they must be "independent" from each other in a mathematical sense, which I propose a criterion for in the paper.

    > The *ONLY* thing that matters is how many DISTINCT observers there are...

    Then I was right that you think measure can only be proportional to the number of observers. See my comments on that in my November 28, 2011 11:52 PM reply above.

    > Miroljub is excited to see what sort of arguments you will bring forth that he has not rebutted yet.

    I received the email. It should be an interesting discussion. I will probably send my reply to the email tomorrow.

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  40. Ok good, so you are not a dualist.
    I've encountered quite a few MWI supporters who recognize the flaws of MWI and think they can solve it by resorting to dualism, so had to be sure :)

    Yes you are right, measure can only be poportional to the number of obsevers.
    Which is why I _know_ MWI will never solve the Born Rule issue "naturally".

    So pre-split you'd only be one person (obviously) and afte the suicide, you'd also be alive.
    Sure you'd know that a dead body ended up in the other branch, but noone DIED.

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  41. I am not a dualist - as you'd know if you've read my MCI paper - but I can respect their views as some of them make interesting arguments, especially David Chalmers and his 'hard problem'. My 'partial brain' eprint can be considered to contain an argument against the need for dualism: http://cogprints.org/6321/

    qpdb wrote:
    > Yes you are right, measure can only be poportional to the number of obsevers.
    > Which is why I _know_ MWI will never solve the Born Rule issue "naturally".

    I don't know what you mean by "naturally", but your second statement does not follow from your first one there.

    > So pre-split you'd only be one person (obviously) and afte the suicide, you'd also be alive.

    That is obviously false, and I have many times explained here why it is false. If measure _is_ proportional to the number of observers, and if an MWI is true so the Born Rule holds in it, then in that MWI we know that the number of observers before the suicide _is_ larger than the number afterward, as I proved in various posts above.

    If the observers CAN be tracked over time, then half of them certainly died. If they CAN NOT be, then ALL of them died, but were replaced by half as many new observers. From a utilitarian viewpoint - that is, FAPP - it doesn't matter which of those cases applies. In either case, the QS idea fails.

    qpdb, my patience with your repetition of the same claims that I have already debunked here several times has worn thin. Anyone else reading these comments will have already had ample opportunities to read both sides of this dispute. If you insist on maintaining your claims, then you may email me with any _new_ arguments you think support them. However, this thread will now be closed to further replies by you if they are in the same vein; I will delete such replies. You may still comment on other topics to other posts of my blog.

    ReplyDelete
  42. I was about to say the same thing, it seems you and me are stuck on this topic, which is probably why we have started derailing over to "does MWI even have a chance of being true?" naturally.

    We are eagerly awaiting your response to the paper. So let's rather focus our energy there.
    You may delete any of the posts you feel are non-productive in this comment section.

    The last thing I will say is this in a last attempt.
    If you are to say X has really died that implies that you have to be able to "track" the observers.

    If not it doesn't really matter that there are now 50% less X's in the "multiverse", sure it is sad, but noone really endedd their life is that is the case.

    If however you can track, then you have to explain where these observers are before they differentiate, since you hold that there are indeed more than just 1 X before the suicide.

    I think this is where everyone gets stuck in this debate and where you claim everyone misunderstands.

    So I suggest you open a new thread about it on PF.com, Stackexchange and LW.com

    If you do so on these 3 "major" discussion boards where some believe in QS, then maybe you can shatter this myth once and for all.

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  43. I'll respond on the paper either today or this weekend for sure.

    qpdb wrote:
    > If you are to say X has really died that implies that you have to be able to "track" the observers.

    That doesn't make any sense. If you can't track an observer, that means he no longer exists later, for sure.

    In my eprint I discussed how measure works in the QS situation, resulting a 50% "effective probability" of death. To wrap up this discussion, I refer any readers to that: http://arxiv.org/abs/0902.0187

    > I suggest you open a new thread about it on PF.com, Stackexchange and LW.com

    The internet is not a good medium for convincing people with entrenched views to change them, on any issue, no matter how clear cut. Perhaps it's too personal; no one likes to lose a debate. Attempting it would be a poor use of time.

    Instead, to get my views out there to a wider audience, which could recruit some supporters, at some point I'll try to polish and publish my anti-QI paper. I've had one offer to publish it but would prefer a better-known journal.

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  44. I think you may be underestimating stackexchange and PF.com

    Stackexchange has some really outstanding PhDs and PF got quite a few too.

    I think it is easier to get someone to agree that they are wrong over the internet than it would be face to face.

    I know quite a few people who has had their stuff published in reputable journals and I can tell you that just because something is publishe does not mean it will get ANY attention.
    I spoke to a guy who had 2 papers published in FoP he had not heard any comment on either of the papers in 2 years...

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  45. This idea that you are immortal (in fact the only immortal in your experience of the universe) is completely idiotic, you were in a state of non existence prior to your birth which is the equivalence of being dead. To claim that it is impossible to return to that state of non existence by means of some quantum loophole is paradoxical and smells of Kurzweillian BS.

    ReplyDelete

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