Quantum uncertainty vs determinism

Discussion in 'Physics & Math' started by Laika, May 18, 2006.

  1. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I do not strongly disagree, but prefer to believe that "I" am non-material, rather than "I" am my brain, a material thing governed by the laws of physics which allow no possibillity of any real choice, unless you want to defined "choice" as doing exactly what the laws of physics require.

    If that is what you mean by "choice" then a rock "chooses" to fall when released from your hand.

    I close with a question, not to challenge you, but wanting to confirm (if true) that you are making an idenity between "you," the choser, and your brain. If not, please tell what you think "you" are. I think "I" am a subroutine in a real time simulation, as discussed in my long essay. (Again I use quotes around "me" "you" "I" etc to clearly refer to the subject of psychology as opposed to the subject of biology (or physics).)
     
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  3. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I followed your drift, but not fully all the details, so I will tell what I think about Bohm's views as I understand them. I have read his book "The Undivided Universe" reasonably carefully, but do not recommend it to you, except to skim, as the QM math in it gets rough going even for me at spots.

    The idea in it (and most of his other writting that I have read) is very appealing to me, but unfortuantely I have convenced myself that he is wrong if I understand his "guiding waves for classical particles" POV correctly, because he is violating the Pauli exclusion principle, and that is too clearly true as it explains, among many other things, why the periodic table of the elements is as it is.

    I will only outline my thoughts on my proof that he is wrong. Anyone who could follow them in detail, can surely create a rigorous proof from the outline that follows:

    Imagine two electrons, A & B, launched into a two-path-possible interference system, but the two paths are of unequal length. In Bohm's POV these electrons are classical and thus travel only via one path but the "guiding wave," GW, travels both paths and is present and active as the two paths are rejoined to make the interference pattern. Already, there is some problem in that the GW rate of progress, not faster than light speed, thru the longer path could not be present to guide the electron, traveling at nearly the speed of light, thru the shorter path, but I agree to not notice this (or accept Bohn's arguments* that sort of have the entire past and future "mixed" into the present.)

    I launch B a little after A so that if B goes by the shorter path and A by the longer one, both emerge together. Now other parts of Bohm's theory, consistent with the standard fact that each electron (or photon) only interfers with itself, require A & B to be guided only by their own GW, I.e. GWa guides A and GWb guides B, but A and B are electrons with spin 1/2 so they are Fermions or follow the Pauli exclusion principle or must be identical in all their physical proprerties. (One can regard one of the muons as a "light electron" in that it is identical to the electron except for having less mass, but all the heavy or normal electrons are well established to be identical.)

    Yet the only way that GWa can guide only A instead of B is if there is a difference between A & B. (I like to summarize this by saying that for Bohm to be correct: "Every electron in the universe must have a unique name.")** This is why I can not accept Bohm's POV, even though it appeals to me strongly. - I do not like QM as it can not tell me what a "measurement" is. Also QM is making all sorts of very counter intutive predicitons, which unfortunately have all turned out to be completely correct. :bugeye: In my case it took years, before I became so confortable with photons going via two different paths and yet being "good particles" in photoelectric effect or when selecting only one atom to excite etc. that these intutively impossible actions are now "no problem" events for me.
    ------------------------------
    *He is found of illustrating this idea with a bowl of colored water and clear oil floating on top, which if carefull mechanically stired by a revesible machine to mix and then very exactly "reversed stired" will nearly return to the original conditions. Illustrating, at least for him, something about the complex "entangled oil/water system" at end of first half of the stiring cycle contains both the past and the future within it. I think that is part of the sense of the title "Undivided Universe" book. Universe is united in time and space; (Both are sort of required to be consistent with GR's ability to mix time and space as one changes frames.)

    **If that were true, then there would only be only essentially one chemical element, hydrogen, (with many isotopes of different weight and slightly different chemistry) as 100s of orbiting electons could all be in the ground state, instead of only two - the spin up and spin down pair that occupy that level in He case.

    BTW you will like to look at:
    www.simulation-argument.com/
    where Nick Bostrom suggest that the universe is just a simulation. (I have not read that for some time, but seem to recall Nick and others suggest our entire universe is just a computer game some more intelligent kid is playing.)
     
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  5. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    From your last paragraph:
    I do not intend or want to disturb you tranquility, now or by my prior "Bohm is wrong" post. Now I only want to suggest that you may find the writtings of Bishop Berkley interesting. He has not been read much since physics and materialism have had so much success, but he has a logically sound (but I think false) position.

    Computer simulations were of course unknown in his time (300years ago?). In his view we are all, universe included, just thoughts of God, but in some sense we are also "lessor spirits" who can really chose to sin.

    I especially like his reasoning about miracles and the normal regularity of the universe following the physical laws. -- If the universe were not highly regular, but random, then God could not make miracles as they are exceptions to the regularity of physics.

    In my long essay on Free Will (and the part of the mechanisms of vision directly related to FW and more fully discussed in its Ref. 1) I am really walking in the footprints the good Bishop made long ago, except I replace God with a parietial simulation that is making "me" and the only universe that "I" directly experience as contrasted to the "external universe" that I, as a trained physicist, INFER exists, but can not be sure it really does.
     
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  7. c'est moi all is energy and entropy Registered Senior Member

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    I think you should reconsider that opinion. Bohmian mechanics is the only reasonable interpretation for me. I can't tell it from the maths, but it works when applied to problems outside physics. If you've read "Unfolding meaning, A weekend of dialogue with david bohm", then you simply must like this great scientist.

    If one name should be mentioned about the refutation of Bohm's theory, then it should be Bell. Not because he refuted it, but because he SUPPOSEDLY refuted it! He was in fact a proponent of it. What Bell did, was show that any hidden-variables formulation of QM must be nonlocal. Exactly what Bohmian mechanics is. He did not show that determinism was impossible, which is a false claim everybody adheres to these days.

    (http://plato.stanford.edu/entries/qm-bohm/#hv ; Bell, J. S., 1987, Speakable and Unspeakable in Quantum Mechanics, Cambridge: Cambridge University Press., 160)

    Bohm in fact just re-discovered (and modified) the interpretation from de Broglie:

    Isn't it funny that Pauli comes into the play?

    As you said,

    Aren't you forgotting non-locality?

    observe Bell yet again:


    Recall the double-slit and how Feynman talks about it in his Lectures on physics:

    Compare this to Bell (Bell 1987, p. 191):

    In Bohmian mechanics, the wave description is not complete. There is no problem for the concept of measurement. On the other hand, for copenhager's rests the problem how the schrödinger equation can be deterministic (when not measured), and suddenly become random (collapse to an eigenstate)? It's void of logic. Bohm introduces the conditional wave function and the effective wave function, and correctly uses a systems approach in contrast to the standard view where somehow mathematical waves, an ill-defined observer and an obscure collapse pretend to be a good explanation/interpretation. You simply can't use reductionism when you're dealing with nonlocal quantum systems.

    Apparently, in Bohmian mechanics, the distinct pilot wave is a fundamental property.

    All these "counterintuitive" predictions are accomodated by Bohmian mechanics as well. I see no argument in that to accept the illogical orthodox interpretation, which frankly seems to be the reflection of a society gone loose.
    I think that if I understand Bohm's more philosophical writings about this, is that the particles are really the expression of a more fundamental implicate order from which it originates (quantum potential). Like his example with the bowl and the viscous fluid in it. You could put a drop of dye in it and stir it n times. Now you add another drop but a little further. Repeat this same procedure adding a drop each time along an imaginary line, and stirring it n times. Each time you will see the drop dissolve when you stir it. Now we stir the device in the opposite direction very fast, and we observe what appears to be a solid object - a particle - moving through space. What Bohm is saying, is that motion and time are unfolded properties. The behaviour of the 'particle' here is a constant enfolding and unfolding which depends on the times you turn the device, call it T. The relation to time t is only contingent because it is T that is directly relevant to de description of the implicate structure. As these drops cannot be unfolded at the same time, bohm calls them asynordinate . Yet, at any moment, the whole implicate order is present - hidden for the eye. Bohm concludes that time has no primary role here, and that the law of the structure would involve aspects of the degrees of implications. Yet, it would not be deterministic through time. As he says, all there is needed for law is ratio in the orders that are primarily relevant.
    That is why his interpretation is both, deterministic and not.
    The electron is an image of our perception. Our perception is real, so particles are real. We can only work with our images, being real in their own respect. It's a matter of seperating two worlds that are intrinsictly interwoven. Maybe there are beings that dwell in the other world, and can't measure the particles and are poundering about the same obstacles in reverse.
     
  8. c'est moi all is energy and entropy Registered Senior Member

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    I love discussion on this. I don't think it could be disturbing, only if you can't get out of your view anymore.
    the link on simulation seems really good and might provide me with some good material for my thesis
    I've encountered Bishop in some books. However, I don't think we need to exclude god (or God, or gods, Gods). That seems to be a disease created by the self-assured ego that doesn't allow to be controlled/interferred with so personally. It probably also has to do with the disgust rational people have from institutions such as the church. However, as a logical entity, it can fulfil a role (for me at least). Being such an old concept, I can't believe it would not be something inherent in nature. It's the thing you can't name, can't compute, can't understand, it's the why, and the "AND" between any and everything. Too bad that the concept has been suffocated by evil people. It seems spoiled now.
     
  9. MacM Registered Senior Member

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    "I" being the material body beyond the brain are mere extensions of the brain.

    Other than some cosmetic component your hands and feet have no personality. They are but living tissue. You are your brain. Everythingelse is nothing more than appendages of the brain to give it the ability to carry out its tasks.
     
  10. c'est moi all is energy and entropy Registered Senior Member

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    Macm,

    I think you should read the papers of Billy T first (which is the bare minimum, and anyone who likes to discuss this matters cannot permit himself to overlook Karl Pribram, one the most important researchers of this century). You can't disuss something you haven't read. If you did read it, then accept my apologies (but it appears to be a negative).
     
  11. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I agree his POV is much more reasonable than the Copenhagen school's QM and In most simple experiment predictions /calculations produces exactly the same results. Unfortunately not in one I thought of.

    Bohm's math is OK as far as I can tell. (I would expect that as he is much better physicist than me.) His casting of physic into "classical particles" with "guiding waves" seems generally OK to me also. I wanted to believe it all, but have some experience with interferometers and unfortunately thought of the "proof" I outlined and that made that impossible for me to abandon the Copenhagen view, much as I dislike it's "measurement" being outside of the theory.

    I do not think electrons can both be all identical and yet interfere only with themselves in Bohm's theory. The guiding wave of another must not guide another electron that is nearby its electron. I.e. Each must recognize its own so "its own" can not be identical with any other electron in the universe as someday one now on Mars etc may be passing thru the interferometer at with the one a particular guiding wave is supposed to exclusively guide and falsely (to experimental results) guided also.

    The fact that electrons are all identical is essential to the world, as we know it. EXTREME consequences follow if this is not true. - Completely different chemistry and elements to name just one.

    I agree that Bell is important as you state. In one recent post here, I mentioned that he had taken the best "near miss" shot at "hidden variable" but did not kill them as a reasonable possibility. If you have never been thru the math of his inequality, you should try - it really is not that hard.
    No, just I do not often like to think about the pair wise (of three) combos that are possible. So I mentioned, especially since I was talking about Bohm, the idea that future past and space may all be mixed in to the present "here and now" as Bohm suggests. (Recall my mentioning in footnote his oil& colored water experiment - I think it is the cover photo on one of his books.)

    Yes Bohm's mechanistic view is much more appealing than Feyman's "no one know how it happens" that is why I would love to believe Bohm. As an experimental physicist, one relative weak in math of the modern accepted views and even totally ignorant of GR etc I crave mechanistic models. Unfortunately, nature seems not feel it is necessary to work so that humans can have them.

    Yes, it was dye, not oil. Memory failed me. Even as I was writing that, I was thinking there is something wrong with the story I am telling, as gravity does not reverse and oil floats! However, I wanted to refer to future be available to present as Bohm suggests, so I continued to write.

    I will let your last paragraph go without comment. What is real is too tough for me. some where you mention God, sort of indicate that you beleive in him/her etc. and that is fine with me in sense I will not agrue against God's existence. That is too strong a position for me to take. I am basically agnostic, but do not even liket to think much about that as Pascal had a good point as to why I should be a beleiver.

    Hard to argue with almost anything Pascal ever said said when he was bieng logical. Reading his exchange of letter with some poor bishop who the church had selected to defend the idea that "nature abhors a vaccum" was why the mercury rises in an evacuated tube is fun, but as I like underdogs, I was soon hoping Pascal would go too far or at least easy up on the bishop.
     
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  12. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Thanks for clear answer. So well done, that I will ask another question (you have come late to this discusion, at least in this thread, so I do not know where you stand on some points):

    Do you think any real choices are ever made by "you"?

    (I.e. by your body/brain system, which being material is governed by the laws of physics at an atomic level, etc so that the motion of every atom (or molecule such as a neuro-transmitter) is just doing what physics laws require and the total of all these motions makes your nerves discharges etc to make all your acts just the inevitable (QM excluded* for the moment) result of the deterministic laws of physic.)
    ----------------------------------------------
    *IMHO, the inclusion of QM is probably not correct for brains and body or even nerve scale objects, but even if it were (The tiny microtublars of cells being the point/scale where QM might enter.) then there would still not be any “real choices” made by "you" just random QM statistical in your different decisions, or the illusion of free will.)

    Do you care to try to come up to speed with comments on this?
     
  13. MacM Registered Senior Member

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    10,104
    Actually "No". My comments were in response to his request for my opinion or my description. Unlike many here I have my own opinion and do not merely recite what I have read regarding the opinion of others.

    Please Register or Log in to view the hidden image!

     
  14. MacM Registered Senior Member

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    Absolutely. The brain computations are independant of prearranged or "deterministic" schedules. It evaluates inputs and makes decisions. The physics of it may be considered deterministic but not the results.

    That is the chemical/electrical process are physical and obey deterministic physical laws but the computation is totally independant of any prescribed pattern and ones actions are the result of the computed process results.

    To believe otherwise requires you to believe that nobody is responsible for any action. That is wholly unacceptable.
     
  15. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I completely agree this (part I made bold) is possible, and I hope true. In fact it is the central point of my long essay on free will, but rather than just assert it, I give several arguments why it is likely to be true.

    IMHO, that is not much of an argument. Unfortunately, nature appears to do a lot of things I find "wholly unacceptable." Did you read my post discussing Bohm's POV telling why I am strongly attracted to it, but think it false, and continue to believe in the "wholly unacceptable" Copenhagen POV of QM?

    PS - MacM I admit to being a crackpot in the field of cognitive science. You I think admit the same in physics. Why not read my essay and be a (crackpot)^2 or "square crackpot"? There are lots of "round crackpots" posting here - I.e. all around here,

    Please Register or Log in to view the hidden image!

    but you could be one of the few square ones, if you join me in idea that "we" are not bodies but parts of a computation. Your more than half way to this conclusion already if your bold text above is truly reflective of your POV.
     
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  16. Nim Registered Member

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    By your description, hasn't Bohm once again given primacy to the observer and the act of observation (i.e., measurement) as the means of "unfolding" the implicate structure, thereby placing himself right back where the Copenhagen interpretation was stuck, with a subjective, self-referencing interpretation of reality? If so, he has not really advanced the ball very much in terms of understanding the relationship between the perceiver and the "real world" over the approach of Bohr or Feynmann.
     
  17. DaleSpam TANSTAAFL Registered Senior Member

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    Gladly.


    In the 1970's there was a lot of philosophy work on the definition of "person". I don't remember any of the proposed definitions currently, but that would be a good starting point.


    => means "implies"
    !=> means "does not imply"

    -Dale
     
  18. DaleSpam TANSTAAFL Registered Senior Member

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    Interestingly, you could also make a similar argument that you are your gonads. Everything else in your body, including your brain, is used for maintaining homeostasis (i.e. constant temperature, blood sugar, oxygen, etc.). Only the reproductive system does not participate in homeostasis, so everything else can be thought of as nothing more than appendages of the gonads to give them the ability to carry out their tasks.

    That certainly doesn't make your suggestion wrong, but it is usually a fun tangent.

    -Dale
     
  19. MacM Registered Senior Member

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    I don't know about you but mine just hang there and do nothing until my brain makes my pecker hard.
     
  20. DaleSpam TANSTAAFL Registered Senior Member

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    In this case the argument is not a question of control, but of physiological support. The brain works in all sorts of ways to keep the gonads alive, but the gonads do not work in any way to keep the brain alive. So the gonads have the primary role and the brain is supportive from a purely physiological standpoint.

    -Dale
     
  21. c'est moi all is energy and entropy Registered Senior Member

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    Hehe, Bohmian mechanics is sometimes also referred to as "Quantum theory without observers". The schrödinger equation is taken as only part of the description -> the positions of the particles are the "hidden variable" (not much hiding going on!). In the double-slit experiment, particles will follow a deterministic path guided by the waves. There's no observer causing it to collapse when actual measurement takes place. The waves when going through both slits, make up partial waves. When they interact with other things (gas molecules, light, ...) they won't be able to superpose no longer. Hence, the path of the electron will be determined by either one of the partial waves, making it look as if there is no "wave aspect" involved no longer. Yet, all that happened is a change in configuration space (determined by the position of the wave and all other molecules involved), and depending on the initial position of the particle, it will go left or right.

    I'm researching the problem billy T has mentioned about the pilot wave-particle relation. All I can say for the moment is that it seems to be the first critic of this kind. I'll need to read some more. But it appears to me that his philosophical writings about wholeness difer from his bohmian mechanics in important ways, which seems absurd for such an intelligent person.

    http://www.mathematik.uni-muenchen.de/~bohmmech/Poster/post/img7.gif
     
  22. c'est moi all is energy and entropy Registered Senior Member

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    I'm sorry, but I forgot to answer the actual question.

    The unfoldment and enfoldment is an ongoing process which has nothing to do with observers whatsoever. The observer is simply a participant in this. For me, it appears to be a description for the same old philosophy of cycles, i.e. creation - destruction - creation - ... What Bohm did (at least, the way I see it), is refine this notion of the cycles in nature. We take part in this process, and I'm convinced that the "particle part" is only related to our conscious thoughts. We do take part in the enfolded whole - our subconsciousness does. We can't "reason" about that part of us, much as we can't reason why we suddenly feel sad or happy when nothing seemed to have caused this. But we listen too much to our thoughts - we OVERthink - and that is a real disease in our societies. (Bohm's book about this is called "Thought as a system").

    Thus, the act of measurement is an act of unfoldment because the "observer" is part of a particular system. But that's not at all the same as the collapsing problem. Here, the waves don't mysteriously vanish (or decohere). They are prevented from superposing, creating different paths (paths don't even exist in copenhagen int.) to follow for the particles.
    I don't know how to rhyme this with his example of the jar and the dye, and how a particle may be a proces of enfolding and unfolding ... because that would be giving the waves a superior position, which they don't have in bohmian mechanics. Yet, all his writings are full of statements that the whole is more important than the parts. Maybe, the "guiding" done by the waves makes them really the master of these particles. And "appearing" and "disappearing" such as the drop of dye creating the illusion of a particle, is possible because it follows many paths across the galaxy of which we are not aware.
     
  23. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Not following you here - what is the conflict? First let me be sure who "his" refers to, me or Bohm. I only know of Bohm's writing about his version of QM, but recal you mentioning he is active in philosophy, so probably "his" is refering to Bohm, not me. Is that correct?

    If referring to me, which I doubt, what "philosophical writings about wholeness" would you be referring to? I did make a crude attempt to summarize Bohm's physics but clearly said I could not accept it much as I would like to. So almost sure "his" refers to Bohm, also I think he is at least better educated, if not also more intelligent than I am.

    PS - My agrument against Bohm's QM (Namely that it implies every electon is unique to be guided only by its own pilot wave.) is an original idea of mine. I doubt if you will find any reference to it as prior to the forum post it is only a margin note I wrote in his book.
     
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