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Thread: Taboo -Quantum mechanics and conciousness

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    Taboo -Quantum mechanics and conciousness

    I'm reading "Quantum Enigma" by Kuttner and Rosenblum, 2006, and they claim a lot of scientists will not confront the questions raised by the clear connection between matter and mind - demonstrated by Quantum theory.

    They kind of imply that Einstein realised what the Quantum spookiness meant from a philosophical point of view, and this is why he was so troubled with QM theory. Could Einstein's intuitional genius have known something could not be quite right about QM?

    How true is this? I was wondering if any scientists might be willing to tell us what they think.

    I was also wondering if perhaps physics will get stuck at QM level without ever fully understanding it - until someone adresses the bigger conclusion.

    (I put this in ATM because it's all hypothetical and thought this might get bumped anywhere else).

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    Quote Originally Posted by Jetlack View Post
    (I put this in ATM because it's all hypothetical and thought this might get bumped anywhere else).
    If you're not actually advocating their position, which it doesn't sound like you are, it should go in Q&A or General Science.

    At any rate, my understanding (and again, not a scientist) is that the reason scientists don't pay attention to it is that it's wrong.
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    First of no clear connection between matter and mind has been "demonstrated by" Quantum theory. Implying that qualitative characterizations of philosophical characteristics that are only presumed to exist based on those philosophical arguments as "demonstrated" is massively intellectually dishonest.

    Yes Einstein had issues with QM that had nothing to do with a matter mind connection. You said they "imply that Einstein realized what the Quantum spookiness meant from a philosophical point of view, and this is why he was so troubled with QM theory" but leave it to us to assume what they "meant" it to mean. Is the mind matter connection in fact what you meant?

    Einstein's issues was specifically related to the concept of definite states and statistics without definite underlying states for those statistics to describe. His issues were very realistic ones as opposed to the philosophical tripe that this book appears to be implying is "demonstrated".

    As for Einstein's intuition about QM only nature gets to answer those kind of questions and we have yet to learn how to ask the right questions to settle that debate, though we have gotten much closer.

    Will we get stuck at the QM level. That depends on what you mean by stuck. On purely philosophical grounds, possibly. Defining that as not "fully understanding it" may in fact be like saying we don't know which way is up and down in space because we don't fully understand space. Then again you may not fully understand the non-existence of question you are asking.

    Questions and Answers would have been a better place for these questions.

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    Quote Originally Posted by Gillianren View Post
    If you're not actually advocating their position, which it doesn't sound like you are, it should go in Q&A or General Science.

    At any rate, my understanding (and again, not a scientist) is that the reason scientists don't pay attention to it is that it's wrong.
    Oh you would say that! Just because i beat you in that other argument :-)

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    Quote Originally Posted by Jetlack View Post
    I'm reading "Quantum Enigma" by Kuttner and Rosenblum, 2006, and they claim a lot of scientists will not confront the questions raised by the clear connection between matter and mind - demonstrated by Quantum theory.
    As others have said, there's no such "clear connection". There's an interpretation of quantum theory, involving observers somehow "collapsing the waveform", which was once fashionable and now isn't.

    Grant Hutchison

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    My wan,

    "First of no clear connection between matter and mind has been "demonstrated by" Quantum theory. Implying that qualitative characterizations of philosophical characteristics that are only presumed to exist based on those philosophical arguments as "demonstrated" is massively intellectually dishonest."

    Okay I'll take a stand then, since it appears I need to in order for this to stay in ATM.

    Its clearly accepted in every book on QM I've read that the "observer" collapses the wave/particle duality in one way or another. Although many books or phycists wont make the obvious connection between an observer and conciousness does not mean its no been demonstrated. That could be because it does appear to be taboo to get into this conversation amongst many phycists. Apparently Feynmann, when asked these questions by students would make sure the door was closed and no-one was listening before discussing the implications of conciousness and matter in relation to QM.

    But the common denominator in the Quantum enigma is the observer/mind. I think that has been demonstrated and it is no more dishonest to make that mind/matter connection than it is to theorise about the horizon around a black-hole.

    "Yes Einstein had issues with QM that had nothing to do with a matter mind connection. You said they "imply that Einstein realized what the Quantum spookiness meant from a philosophical point of view, and this is why he was so troubled with QM theory" but leave it to us to assume what they "meant" it to mean. Is the mind matter connection in fact what you meant?"

    I think the spookiness part was about non-locality. But yes the book tells of a dinner one of the authors had with Einstein. Einstein apparently met from time to time with young physics grads etc, and was always interested in asking them about what they thought of QM. On this occasion Einstein asked the author what he thought about QM from a philosophical point of view. The author states that when he was a young grad they were too busy using QM for practical calculations, work etc.... So he found it strange that Einstein seemed very keen to discuss not the technical apsects so much, but the philosophical implications.

    "Einstein's issues was specifically related to the concept of definite states and statistics without definite underlying states for those statistics to describe. His issues were very realistic ones as opposed to the philosophical tripe that this book appears to be implying is "demonstrated"."

    Well thats your opinion :-) From what ive read about Einstein he was very much a philosopher and i think his known comments would support that.

    "As for Einstein's intuition about QM only nature gets to answer those kind of questions and we have yet to learn how to ask the right questions to settle that debate, though we have gotten much closer."

    How much closer are we? If we still dont understand why an observers existence effects the outcome of experiements with subatomic particles then i dont see us as being any closer to an answer than Einstein, Bohr, Heisnberg etc...


    "On purely philosophical grounds, possibly. Defining that as not "fully understanding it" may in fact be like saying we don't know which way is up and down in space because we don't fully understand space. Then again you may not fully understand the non-existence of question you are asking."

    Well thats exactly what the book is saying. The answer may be philosophical and if we do not explore it then we wont ask in the right place so wont find the answer. These two phycists are complaning that because its a taboo type subject we wont face up to the mind/matter enigma.

    Arthur C Clarkes comment about how tehcnology can appear like magic to those that dont understand it is a pretty good analogy for the weirdness of QM.

    I think its a reasonable assertion.

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    Quote Originally Posted by grant hutchison View Post
    As others have said, there's no such "clear connection". There's an interpretation of quantum theory, involving observers somehow "collapsing the waveform", which was once fashionable and now isn't.

    Grant Hutchison
    Then why does every description of quantum mechanics come with a long passage on the significance of the observer? Okay maybe one can argue that its just the obverser and not their mind that impacts on the experiment.

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    Quote Originally Posted by Jetlack View Post
    Its clearly accepted in every book on QM I've read that the "observer" collapses the wave/particle duality in one way or another.
    Then I can only suggest that you are reading the wrong books. The current interpretation involves decoherence: if a quantum state is involved in enough interactions with the outside universe, the waveform collapses, whether or not a "conscious observer" is involved.
    Here's Murray Gell-Mann, in his book The Quark and the Jaguar, explaining the importance of decoherence:
    This process answers a question Enrico Fermi often put to me in the early 1950s, when were colleagues at the University of Chicago: Since quantum mechanics is correct, why is the planet Mars not all spread out in its orbit? An old answer, that Mars is in a definite place at each time because human beings are looking at it, was familiar to both of us, but seemed just as silly to him as to me. The actual explanation came long after his death, with the work of such theorists as Dieter Zeh, Erich Joos and Wojtek Zurek on the mechanism of decoherence, such as the one involving the photons of the background radiation.
    Photons from the sun that scatter off Mars are also summed over, contributing to the decoherence of different positions of the planet, and it is just such photons that permit human beings to see Mars. So, while the human observation of Mars is a red herring, the physical process that makes the observation possible is not a red herring at all, and can be regarded as being partially responsible for the decoherence of different coarse-grained histories of the motion of the planet around the sun.
    Grant Hutchison

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    it's "measurement" that collapses the waveform, measurement roughly being anything that allows a quantum property to have an effect on the macro world, such as moving the needle of a Geiger counter. A Geiger counter is not conscious, yet it makes measurements that collapse waveforms.

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    Quote Originally Posted by Jetlack View Post
    Then why does every description of quantum mechanics come with a long passage on the significance of the observer? Okay maybe one can argue that its just the obverser and not their mind that impacts on the experiment.
    See above. A lot of pop-sci still hangs on to the "conscious observer" interpretation, presumably because it enhances the alleged spookiness of QM.
    But it's not required by the theory, and there are perfectly sensible explanations that don't involve the intervention of consciousness. Notice, please, the word "silly" offered by Gell-Mann: that's about as condemnatory an adjective as a physicist can produce.

    Grant Hutchison

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    Forgive me if this is out of place, but it seems relevant (in my head):

    I never liked that "if a tree falls in the forest and no one is there to hear it, does it make a sound?" thing.

    I mean, maybe no person is there to hear it, but leaves of the near-by trees would be jiggled, wouldn't they? The air itself would still be vibrated...

    (Set up a tape-deck and a timed let-go-the-pre-cut-tree device; you'll record the tree falling-sound... though the microphone is hardly self-aware.)

    Without knowing much about QM (yes, I know the above is different), I've never seen why it needed to be a concious (or intelligent?) oberserver that collapsed waves.

    Thanks for the photon-mars description, Grant.
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    Quote Originally Posted by tdvance View Post
    it's "measurement" that collapses the waveform, measurement roughly being anything that allows a quantum property to have an effect on the macro world, such as moving the needle of a Geiger counter. A Geiger counter is not conscious, yet it makes measurements that collapse waveforms.
    I kind of understand that, but how would an inanimate oject know its being measured by another inanimate object?

    I know its no weirder really than the wave collpase but neither does it make any more sense.

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    Quote Originally Posted by grant hutchison View Post
    See above. A lot of pop-sci still hangs on to the "conscious observer" interpretation, presumably because it enhances the alleged spookiness of QM.
    But it's not required by the theory, and there are perfectly sensible explanations that don't involve the intervention of consciousness. Notice, please, the word "silly" offered by Gell-Mann: that's about as condemnatory an adjective as a physicist can produce.

    Grant Hutchison
    Hi Grant,

    Thanks for the ealrier link on decoherence re Gell-Mann, and you are right I had not come across it. I read the wiki page on it - minus the calculations. Okay so there's another theory which solves the enigma from the point of view of effects of conciousness.

    However, it appears this theory is related to the "Many worlds" theory by Everett, which I've also read about before. To be honest i think thats a pretty far-out interpretation and the Wiki page says:

    "Thus decoherence, as a philosophical interpretation, amounts to something similar to the many-worlds approach"

    I'm not saying that means it has no credibility but clearly it implies its just another "interpretation".

    But it could be right - agreed - and that would solve the mind/matter controversy.

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    Quote Originally Posted by Jetlack View Post
    I kind of understand that, but how would an inanimate oject know its being measured by another inanimate object?
    In Gell-Mann's example, the position of Mars is being "measured" by all the photons that bounce of it. Mars interacts significantly and constantly with other bits of the Universe. It's this continuous interaction with other "stuff" that prevents the quantum waveform spreading out over time.

    We can only observe an object by making stuff interact with it: photons, detectors, whatever. But it's not the conscious observation that does the trick; it's the interaction with other stuff. That's why Gell-Mann refers to observation as a "red herring": it's no more than a place-holder for the important thing, which is simply interaction with the rest of the Universe.

    Grant Hutchison

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    Okay been reading a bit more, and Decoherence makes sense.

    One thing that always bothered me about the conciousness collapse theory - thoug i liked it - was that since there has only been conciousness within our solar system within the last few billion years (if we consider microbes to have a consiousness) then we should not be able to see any history of the universe or matter before that time. But we know the planets and stars are older than any biological conciousness of which we have a record etc...

    hence, decoherence solves that paradox because it means non living or non thinking matter collapses its own waves...if i read it correctly.

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    Quote Originally Posted by grant hutchison View Post
    In Gell-Mann's example, the position of Mars is being "measured" by all the photons that bounce of it. Mars interacts significantly and constantly with other bits of the Universe. It's this continuous interaction with other "stuff" that prevents the quantum waveform spreading out over time.

    We can only observe an object by making stuff interact with it: photons, detectors, whatever. But it's not the conscious observation that does the trick; it's the interaction with other stuff. That's why Gell-Mann refers to observation as a "red herring": it's no more than a place-holder for the important thing, which is simply interaction with the rest of the Universe.

    Grant Hutchison
    Okay cheers. I get it and duly submit!

    See I admit it when Im wrong :-)

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    Quote Originally Posted by Jetlack View Post
    "Thus decoherence, as a philosophical interpretation, amounts to something similar to the many-worlds approach"
    Only, I think, in the sense that the other quantum probabilities are rendered inaccessible, rather than non-existent. (BTW: "Many Worlds" seems to have undergone something of a revival of late, despite its counterintuitive premise.)

    Quote Originally Posted by Jetlack View Post
    "I'm not saying that means it has no credibility but clearly it implies its just another "interpretation".
    For sure. The point is just that there is no deep mystery linking mind and matter unless we put one in with our interpretation of QM.

    Grant Hutchison

    Edit: You must have posted your post above while I was typing. There's no reason to "submit" - but I do recommend The Quark and the Jaguar, if you can track down a copy.

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    Quote Originally Posted by grant hutchison View Post
    Only, I think, in the sense that the other quantum probabilities are rendered inaccessible, rather than non-existent. (BTW: "Many Worlds" seems to have undergone something of a revival of late, despite its counterintuitive premise.)

    For sure. The point is just that there is no deep mystery linking mind and matter unless we put one in with our interpretation of QM.

    Grant Hutchison

    Edit: You must have posted your post above while I was typing. There's no reason to "submit" - but I do recommend The Quark and the Jaguar, if you can track down a copy.

    Thanks i will definitely get hold of a copy. Hope its not too full of calculations.

    Some guy i know found out i was interested in physics and he said he had to send me this book from his friend, a phycist,who had come up with some totally new theory of everything called the "Two photon theory" or something like that.

    Anyway, the book arrrives and i open it - its cover to cover mathematical equations. Looks wonderful but cant read a word of it. Almost no writing :-)

    I guess I should have learned calculus or whatever those equations are.

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    Quote Originally Posted by Jetlack View Post
    Thanks i will definitely get hold of a copy. Hope its not too full of calculations.
    None that I can see.
    He draws the occasional graph and talks you through the implications in plain language. That's about as mathematical as it gets.

    Grant Hutchison

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    Quote Originally Posted by Jetlack View Post
    Okay been reading a bit more, and Decoherence makes sense.

    One thing that always bothered me about the conciousness collapse theory - thoug i liked it - was that since there has only been conciousness within our solar system within the last few billion years (if we consider microbes to have a consiousness) then we should not be able to see any history of the universe or matter before that time. But we know the planets and stars are older than any biological conciousness of which we have a record etc...
    So, just what is the specific objective definition of "consciousness"? How, for the purposes of an experiment are we to specifically define what is a "conscious observer" and what is not?

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    Quote Originally Posted by Van Rijn View Post
    So, just what is the specific objective definition of "consciousness"? How, for the purposes of an experiment are we to specifically define what is a "conscious observer" and what is not?
    Well I agree that's probably an unknown. Maybe non-living matter also has a type of conciousness at the planck scale or smaller. But after reading more on decoherence it could also be questioning the defintion of conciousness.

    Assuming for a moment that conciousness is only possible through biology;
    i feel decoherence is more consistent with the fact that this universe has existed longer than we have. If there really was a kind of symbiotic relationship between mind/matter then it fails to explain why we can see a history to all the matter in the universe which pre-dates biological/conciousness evolution.

    The only way around it I think and to still make the case for a mind/matter relationship is if the bang-bang was kicked off by an observer. Other sentient life in the universe having developed before us still would not explain why we see so far back in the universe's history to a time when no biological systems could have had the time to evolve.

    Decoherence does seem to solve the that paradox making the universe not require an observer/mind.

    Or thats how I read it, though I'm obviously not a scientist. I just like to try to get these things right in my head :-) Unlikely I'm sure.

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    Quote Originally Posted by grant hutchison View Post
    As others have said, there's no such "clear connection". There's an interpretation of quantum theory, involving observers somehow "collapsing the waveform", which was once fashionable and now isn't.

    Grant Hutchison
    Not to be flip, but is fashion how these things are determined? To the best of my (flawed) knowledge no one has yet found a way around the logic of Van Neummann's Chain.

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    Quote Originally Posted by Daffy View Post
    Not to be flip, but is fashion how these things are determined?
    I was being flip myself. But I can't help but feel that the "observer collapses the waveform" story persisted in popular science writing, well beyond its useful span, simply because it was fashionable to portray QM as having some deep connection to spirituality.

    Quote Originally Posted by Daffy View Post
    To the best of my (flawed) knowledge no one has yet found a way around the logic of Van Neummann's Chain.
    Well, von Neumann just asked where along the chain of "observational processes" the collapse of the waveform takes place.
    Decoherence answers that it doesn't take place: the waveform just gets so mixed into the overall quantum activity of the universe that only one outcome can be discerned by inhabitants of that universe.

    Grant Hutchison

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    Quote Originally Posted by grant hutchison View Post
    Well, von Neumann just asked where along the chain of "observational processes" the collapse of the waveform takes place.
    Decoherence answers that it doesn't take place: the waveform just gets so mixed into the overall quantum activity of the universe that only one outcome can be discerned by inhabitants of that universe.

    Grant Hutchison
    It may be my (likely) lack of understanding, but it seem that Decoherence simply stops asking the question. That was phrased as a statement, but is actually more of a question itself.

    In other words, the inhabitants of the universe are still just waveforms, no different from anything else. Saying they just can't discern other outcomes doesn't deny that they are there, or explain why they can't be discerned. Or am I misunderstanding? (again, likely)

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    Quote Originally Posted by Daffy View Post
    In other words, the inhabitants of the universe are still just waveforms, no different from anything else. Saying they just can't discern other outcomes doesn't deny that they are there, or explain why they can't be discerned. Or am I misunderstanding? (again, likely)
    I don't know if you're misunderstanding.
    Here's what I believe I understand:
    When a particle or object does not interact with the rest of the Universe, quantum mechanics can't say what it's doing, and can't assign a probability to certain "histories" for that particle. Did the photon go through the left slit or the right slit? No idea. It seems to have gone through both.
    Once the particle interacts with the universe, its quantum histories become entangled with the rest of the universe. To think about the particle on its own, we have to "sum over histories" for the rest of the universe: we ignore all the events that have now become entangled with the particle's history. In quantum maths (which I don't pretend to understand) that "summing over histories" has an interesting effect: the interference terms in the quantum description of the particle disappear (or become very small), and it becomes possible to make probabilistic statements about the route it has taken.
    So stuff that interacts with the rest of the universe smears out its quantum indeterminacy and ends up, mathematically, behaving just like a classical object.

    So the answer to von Neumann's question seems to be:
    1) The object quickly loses indeterminacy once it has interacted with the universe; this interaction may or may not involve conscious observation: it doesn't matter.
    2) The question is anyway ill-posed, since it seems to assume that we are somehow not part of the quantum universe. It perpetuates the idea that the quantum universe has to "turn into" the classical universe at some threshold level of detail. This is like suggesting that Newton mechanics must "turn into" special relativity at some particular velocity threshold.

    Grant Hutchison

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    Smile Six inner dimensions quantum

    Quantum theory has as a baseof six inner or smaller dimensions for the mathematics to take the scale of particle interaction from real world atoms down to particles at the fundamental or Planck scale.

    The current model of six dimensions assumes that at the lowest level the sixth dimension there is an inner boundary to the universe.

    That is one explanation.

    A more complex explanation is that at that point it connects back to the real world at the outer level of the universe. For simplicity the model is that of a ring say a wedding ring with a single diamond. From our position or any position on that ring you could consider yourself the precious diamond. Looking one way everything funnels down into a cone to a point where it can no longer be seen. From any point looking the other way the view is from within the cone to where the light appears to not have yet arrived.

    In other words look down and six dimension funnel in and look up and six dimensions funnel out and are still fully connected. Of course the more complex explanation is not the one favoured by current physics but it is valid none the less.

    Thought is problematic only in that it the basis of metaphysical explanations and highly emotive. A safe option is to say it is beyond the realm of current physics to quantify ... that does not necessarily make it the right option eventually. But for now, perhaps it is a safe one, cheers

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    Grant,

    How does "Decoherence" model fit into John Bell's inequality tests for non-locality and observer created reality? If I have read it correctly his tests prove that either non-locality (Einsteins spooky action at a distance) is true, or that an observer is required for reality to occur - or both.

    Decoherence does appear to make macrospic objects coming into contact with the quantum measurements make the observer obsolete.

    However after reading some more on the web it does appear there is different interpretaiton of "decoherence". Some phycists argue that its a good model for explaining the dividing line between macroscopic classical universe and the universe at the Quantum level - but it still doesnt rid the skeleton in the closet of the observer.

    Another thing about "many-worlds" theory - which seems to be interconnected to "decoherence" or at least is made more likely if decoherence is the accurate interpretation - is that does it not suggest we are all immortal? If universes or many histories are splitting off whenever a decision or a quantum fluctuation effects our lives then is that not breaking one of the rules of physics and nature - the conservation of energy? Is that not a paradox because so many different universes with only small changes appears to be a terrible waste of energy and matter.

    Its funny because i find the observer created reality interpretation far less fantastical than the many-worlds interpretation.

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    Quote Originally Posted by Jetlack View Post
    How does "Decoherence" model fit into John Bell's inequality tests for non-locality and observer created reality? If I have read it correctly his tests prove that either non-locality (Einsteins spooky action at a distance) is true, or that an observer is required for reality to occur - or both.
    I don't recall encountering that statement about Bell's inequality. It showed that any theory which is "local" (in the sense of avoiding any "spooky action at a distance") must contradict some part of quantum mechanics: so we can only keep QM, as it stands, if there is non-locality.
    Experiments using Bell's inequality show that particle behaviour is non-local, so QM passes that test. The interpretation we put on QM is unaffected by this outcome, as far as I can see.

    Quote Originally Posted by Jetlack View Post
    Another thing about "many-worlds" theory - which seems to be interconnected to "decoherence" or at least is made more likely if decoherence is the accurate interpretation - is that does it not suggest we are all immortal? If universes or many histories are splitting off whenever a decision or a quantum fluctuation effects our lives then is that not breaking one of the rules of physics and nature - the conservation of energy? Is that not a paradox because so many different universes with only small changes appears to be a terrible waste of energy and matter.

    Its funny because i find the observer created reality interpretation far less fantastical than the many-worlds interpretation.
    I don't know how it makes us immortal: if you're dead in an infinite number of universes, that makes you pretty dead.
    Your "terrible waste" stance on Many Worlds is a quite anthropocentric approach: why should the Universe care? (I do believe that at least one reason why Everett didn't get due recognition in his own time was pure anthropocentrism: it is much more comfortable to take the "observer" viewpoint, in which the Universe appears to care about us, rather than the "many worlds" approach, in which the Universe quite evidently doesn't give a toss about us as individuals.)
    Anyway, here's Gell-Mann on Many Worlds:
    We consider Everett's work to be useful and important, but we believe that there is much more to be done. In some cases too, his choice of vocabulary and that of subsequent commentators on his work have created confusion. For example, his interpretation is often described in terms of "many worlds" whereas we believe that "many alternative histories of the universe" is what is really meant. Furthermore, the many worlds are described as being "all equally real", whereas we believe it is less confusing to speak of "many histories, all treated alike by the theory except for their different probabilities." To use the language we recommend is to address the familiar notion that a given system can have different possible histories, each with its own probability; it is not necessary to become queasy trying to conceive of many "parallel universes", all equally real.
    Grant Hutchison

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    Hi Grant,

    "I don't recall encountering that statement about Bell's inequality. It showed that any theory which is "local" (in the sense of avoiding any "spooky action at a distance") must contradict some part of quantum mechanics: so we can only keep QM, as it stands, if there is non-locality.
    Experiments using Bell's inequality show that particle behaviour is non-local, so QM passes that test. The interpretation we put on QM is unaffected by this outcome, as far as I can see."


    Maybe i explained it badly.

    http://physicsworld.com/cws/article/news/27640

    "Some physicists are uncomfortable with the idea that all individual quantum events are innately random. This is why many have proposed more complete theories, which suggest that events are at least partially governed by extra "hidden variables". Now physicists from Austria claim to have performed an experiment that rules out a broad class of hidden-variables theories that focus on realism -- giving the uneasy consequence that reality does not exist when we are not observing it (Nature 446 871)."

    It appears to suggest that reality does not exist unless observed. I cannot get into Nature as I dont have a subscription so havent read the paper but the article in Physicsworld has a summary.

    Of course this doesnt prove anything but it is another reminder about how hard it is to rid the observer from QM.

    Also in that Quantum Enigma book it says the tests conducted so far concerning John Bells tests for inequality show that a> either non-locality is inherent in quantum systems, or b>there is no reality without an observer, c> both of those.

    I think the tests the Nature paper is talking about is for the observer reality part of the test.

    "I don't know how it makes us immortal: if you're dead in an infinite number of universes, that makes you pretty dead."

    Thats true :-) However one could also be wounded, partly dead, totally dead or even alive in some of them. But lets asume many-worlds is true. What decides to which universe i am split off to?

    "(I do believe that at least one reason why Everett didn't get due recognition in his own time was pure anthropocentrism: it is much more comfortable to take the "observer" viewpoint, in which the Universe appears to care about us, rather than the "many worlds" approach, in which the Universe quite evidently doesn't give a toss about us as individuals.)"

    Does the many-worlds theory necessarily make the observer viewpoint mute? is it not spossible for both to be correct?

    I am chasing that book down by Gell-mann.

  30. #30
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    Quote Originally Posted by Jetlack View Post
    This doesn't refer to Bell's inequality, but to something called Leggett's inequality, which I haven't heard of. From the report, it appears to rule out a certain class of "hidden variable" interpretations of QM. Again, that's just confirming that QM works the way the maths looks, with no secret variables steering things in a non-probabilistic way. The writer of the article appears to think that this specifically confirms the "observer" interpretation, but I can't see why that should be so.

    Quote Originally Posted by Jetlack View Post
    Also in that Quantum Enigma book it says the tests conducted so far concerning John Bells tests for inequality show that a> either non-locality is inherent in quantum systems, or b>there is no reality without an observer, c> both of those.
    It seems the problem is whether "no realism" actually means "no reality without an observer" or "quantum superpositions can persist if they do not interact with the gross universe". The former often seems to be used as shorthand for the latter.

    Quote Originally Posted by Jetlack View Post
    However one could also be wounded, partly dead, totally dead or even alive in some of them. But lets asume many-worlds is true. What decides to which universe i am split off to?
    Nothing. Random chance. The QM equations assign a probability to your finding yourself in a certain "coarse-grained" history. There's a "you" in all possible histories, but some of those histories have low probability.
    And the observer effect certainly doesn't get you away from this randomness. What decides how the waveform collapses (which outcome is actually observed)? Probability, again.
    That's why some people are keen on these various "hidden variables", which secretely steer the outcome in a specific direction. But, as you see, it's getting harder and harder to come up with hidden variable theories that are compatible with experiment.

    Quote Originally Posted by Jetlack View Post
    Does the many-worlds theory necessarily make the observer viewpoint mute? is it not spossible for both to be correct?
    But what function of "collapsing the waveform" would the observer perform, if she was in every universe observing all possible different outcomes?

    Grant Hutchison
    Last edited by grant hutchison; 2008-Jan-07 at 04:17 PM. Reason: clarity

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