From ggglobus@UCI.EDU Tue Mar 9 07:35:45 1999 Date: Mon, 8 Mar 1999 22:44:13 -0800 From: gordon g globus Subject: [q-mind] Reply to Sarfatti on von Neumann/Wigner quantum mechanics--Henry Stapp From: Henry Stapp Subject: Reply to Sarfatti on von Neumann/Wigner quantum mechanics. I shall use Jack Sarfatti's posting of Mar 7 to explicate the principles of the vN/W approach to consciousness by contrasting it to Bohm's theory, and Sarfatti's. These principles are very simple, but Jack's comments show that they are not universally understood. >From ggglobus@UCI.EDU Sun Mar 7 11:49:27 1999 Subject: [q-mind] Response to Stapp--Jack Sarfatti Subject: Re: [q-mind] Refutation of Stapp's Orthodox QM Theory of Consciousness. > [Jack - prev] > On second reading I find that Henry's position above is logically > inconsistent within the explanatory framework, or paradigm, of my > heuristic formulation of post-quantum physics. > [Stapp] A theory is not "refuted" by being different from an unproven one. [Jack] ... you cannot explain consciousness inside your orthodox quantum theory. You use "consciousness" as a primitive postulate to explain the measurement problem in quantum theory. [Stapp] Orthodox vN/W theory assumes that our conscious experiences are part of a reality that has mathematical properties; that some of the these properties are expressible in terms of the concepts of quantum theory; and that, in particular, the orthodox rules of vN/W QM give very accurate predictions about correlations between aspects of our conscious experiences. By means of von Neumann's analysis of the mathematical structure of quantum theory all of the predictive success of Copenhagen QM carries over to, and becomes supportive of, vN/W QM. The latter is extremely parsimonious as regards basic elements, and eschews speculations based on the idealization that was the conceptual basis of classical physical theory, namely the extrapolation to the microscopic limit of the concept of localized physical object. That concept is very useful in our practical dealings with nature at the macroscopic level, but is not needed in quantum theory, which encompasses all of the valid predictions of classical physical theory, and much more. [Jack] In contrast, post-quantum theory, a larger theory with orthodox theory as a limiting "zero back-reaction" sub-theory, explains consciousness as the direct back-reaction of the motion of matter on its guiding quantum information "pilot-field" in the sense of Einstein-deBroglie-Bohm realism. [Stapp] Can one really "explain" consciousness by saying that it is an action of a postulated classical world (a set of N moving classical point particles) upon the wave function (a changing complex-valued function defined over a 3N-dimensional space). How does one pass by any rational process of reasoning from the existence of this action to the existence of a conscious experience, say an experience of a patch of redness. How can the existence of a "redness experience" be deduced from the existence of an action between two mathematically defined functions: what logically prevents the latter from existing without the former? Bohm, in order to bring consciousness into HIS theory was led to conjecture that there was an infinite tower of higher and higher type wave functions, each acting on the next lower level one, and that consciousness somehow emerged from the mystery of infinity. You, Jack, seek to make the jump to consciousness by invoking back action. But I think anyone can plainly see that it is not going to be possible to actually *deduce* the existence of consciousness from the postulated existence of an action between two mathematically defined functions. Lacking any actual deduction of the existence of consciousness from your premises, about action between a classically conceived world and a function defined over 3N-dimensional space, you must postulate the needed connection, rather than deduce it. You must bring it in because you know it exists, not because it is the neccessary logical consequence of a postulated back action. Orthodox QM also brings in human experiences because we know they exist. The empirical evidence shows also that they are in fact correlated to one another in just the way predicted by the orthodox theory, at least to an accuracy so great that no deviation from these predictions has ever been discovered, if one discounts claims of paranormal phenomema. > [Jack - prev] > The Copenhagen > Interpretation is simply the approximation that "the wave function > has no sources" (Bohm and Hiley, p.30 & 14.6). > [Stapp] Not so! The essential point of the Copenhagen Interpretation is that --- to avoid getting hung up on what is happening at the instruments --- the instruments should be left out of the quantum theoretically described system: the instruments should be described rather in terms of how we human beings normally know and use them. [Jack] If you look on p.30 of Bohm and Hiley, you will see that the true cause of quantum randomness is the absence of the source term. [Stapp] What B&H say there is: "As we shall see ... quantum theory can be understood completely in terms of the assumption that the quantum field has no sources or other forms of dependence on the particles." What they say here, explicitly and correctly, is that in order to get the predictions of quantum theory out one should NOT have a source term: no back action. B&H do not explain the true cause of quantum randomness: instead, they make a very strange statistical postulate about how the single unique real universe is, in some way, statistically distributed according to a quantum probability rule associated with the wave function. This postulate is where the quantum randomness comes from in the Bohm theory. The lack of source merely keeps this postulated statistical distribution intact: it does not cause or explain it. [Jack] The entire basis for the statistical formulation that you use with your projection operators springs from this lack of stabilizing feedback-control loops between the pilot wave and the Bohm point in configuration space. [Stapp] The orthodox statistical formulation neither refers to, nor in any way depend upon, Bohm's theory, which came later. Thus it does not "spring" from Bohm's idea, nor from the lack of your modification of Bohm's idea. What is true, rather, is that if you add your back-action to Bohm's model then you will upset Bohm's project of showing how the orthodox predictions could be mimicked by his realistic and deterministic model, used in conjunction with his odd statistical postulated: Bohm's theory would be upset by your "improvement", but orthodox theory does not even contain the basis for your back-action. [Jack] It's because of this, that Bohr's epistemological Copenhagen Interpretation, and its spin offs like von-Neumann and Heisenberg et-al do make good sense in a limited domain of validity. [Stapp] Thank you! Yes, orthodox ideas do indeed make good sense, which is why quantum physicists use them. If you accept the Bierman presponse results, and wish to accomodate them in quantum theory, then the simplest and most parsimonious tack is to do nothing at all to the orthodox theory except to relax the orthodox demand that the Hamiltonian be Hermitian. Normally in science one tries at first to see whether a small change in existing theory will do, rather than jumping to Draconian measures that involve wholesale importation of radical ideas. .... > [Jack - prev] > "Probability" is used in the "ensemble" sense as a frequency. Given N > identical simple systems completely independent of each other, e.g. no > entanglements among members of the ensemble are permitted. > ..... > But the point here is that this whole explanatory > framework, at the foundation of Stapp's attempt at an orthodox theory of > consciousness, is totally inappropriate to explaining the consciousness > in a unique living human brain with a unique complex personality, set of > memories etc. Henry is over-extrapolating a limiting case of a more > general theory. > > [Stapp, prev] > The orthodox stance as regards the objective probabilities that occur in > quantum theory is that they refer to the individual quantum system: > in Heisenberg's language they are objective tendencies, or potentia: in > Popper's language they are propensities. Predictions involving these > statistical weights > are TESTED by looking, for example, at similarly prepared systems. [Jack] Exactly my point! So, pray tell, what possible "operational meaning", in P.W. Bridgeman's sense (my course with Max Black at Cornell in 1957) can their be to the ensemble of "similarly prepared living Stapp brains"? [Stapp] I said "for example": the propensity interpretation of probability requires no existence of similarly prepared systems. It is a property of a single unique system, and it produces statistical predictions in that real world if there should occur in that one world, a set of similar, but nonidentical, experimental configurations. [Jack] That is "excess metaphysical baggage" IMHO. [Stapp] There is one unique physical world in which similar experimental situations occur, and hence no excess baggage. I have strongly emphasized that I regard the idea of randomness as a mathematical tool that is useful in practice because of our lack of knowledge of the variables that that are controlling the apparently random "Dirac" Choices on the part of Nature, and I have *explained why*, in the one deterministic universe in which we live, this lack of knowledge should produce, in practice, a random distribution with exactly the statistical weights prescribed by the quantum rules. There is in Bohmian mechanics no comparable explanation of the validity of the quantum statistical rules. Rather there is that completely mysterious statistical postulate that one should imagine the entire universe to be a member of an infinite ensemble of universes that all have the same wave function, but in which the classical worlds in these different universe are distributed in accordance with the probability distribution specified by that wave function. Talk about excess baggage! But I *derive* the correct rule for the one unique world, without bringing in any strange assumption! [Quantum Ontology and the Mind-Brain Connection, Ch 10] [Jack] You cannot consistently fall back on David Deutsch's "multiverse" of shadow Stapp clones in parallel worlds because you have R-collapse which the multiverse does not have. Check mate, again! :-) [Stapp] David Deutsch espouses a theory with many parallel worlds, whereas I have one deterministic world with no shadow Stapp clones, and with real ontological collapses. This deterministic process is, to be sure, non-local. Moreover, it involves our thoughts in a way that is not reducible to the local deterministic Schroedinger evolution combined with the deterministic --- though probably for all practical human purposes, random --- Dirac process. > [Stapp] > Orthodox theory does put conscious experience in as basic. [Jack] Correction, your sufficient, but by no means necessary, version of orthodox quantum theory does. The Bohm-Hiley-Vigier version does not do so. [Stapp} The term "orthodox" was the term used by Wigner to denote his rendition of the von Neumann approach, which, like the Copenhagen interpretation, refers to our knowledge, I have been using the word "orthodox" to mean basically the knowledge-based approach of Copenhagen/vonNeumann/Wigner. The Bohm and Everett interpretations are, in this way of using the term, classified as unorthodox. I believe this is in accord with common usage among quantum physicists. Copenhagen and von Neumann defined what was orthodox: the alternative approaches by others who got the same predictions from different starting assumptions are termed unorthodox. I hope we can maintain some clarity by keeping this terminology: Bohm's theory is not called orthodox quantum mechanics even by its supporters, generally: it endeavours to make the same predictions as orthodox quantum theory, and succeeds in certain simple nonrelativistic cases. [Jack] (quoting Hiley) "I will argue that while it is not possible to conclude that the proposal of the direct intervention of consciousness to explain the 'collapse' of the wave function is without substance, there is very little direct evidence that such a process does actually occur." [Stapp] I would say no evidence at all, at least if paranormal phenomena is excluded! Indeed, that is exactly the basic problem here: the experiments are not decisive. This lack of decisive empirical data is why there is dissension among physicists: they have been able to contrive many empirically indistinguishable theories. All theories that yield the orthodox predictions are on a par, empirically, and they can be evaluated only on other grounds, such as parsimony. (Hiley) "I will also show that such an intervention is not necessary." [Stapp] I doubt that Hiley regarded this as a new result that he had discovered: he was merely alerting his audience to the known facts. On the other hand, there is a need to tie the elements of any proposed physical theory to our conscious experiences. Hiley is not denying this. The issue, then, is how are we to introduce into physical theory this tie-in to our conscious experiences: Are the Cartesian assumptions that form the basis of classical physical theory satisfactory? They have led to great disarray in the philosophy of mind. (Hiley) I am extremely worried by the fact that we want to use something we know very little about (i.e. consciousness) to explain away a problem which I fear arises in our, as yet, rather poor attempts to understand the full implications of the quantum formalism." Basil Hiley p. 39 "Brain, Mind and Physics" IOS ISBN 90 5199 254 8 [Stapp] The key question is not whether quantum theory can be understood without consciousness: it is rather whether consciousness can be understood without quantum theory. Bohm seems to think not. And I was told that Hiley expressed agreement about this at Tucson III. If Jack claims that consciousness can be understood without quantum theory then his theory would collapse in ruins. [Jack] I see no conceptual superiority [over my stipulation] of your implicit, covered up stipulation of active conscious experience as attached to R-collapse [Stapp] Your conception of my theory seems very different from to my theory itself. In my theory the state S of the universe is an objective property of the real objectively existing universe, and a person's conscious experiences are real objectively existing aspects of nature that are tied to an objectively real physical system, his body/brain. The collapse of the state S associated with a human conscious experience is an objective change in both the state S of the universe and the state S_b of the person's body/brain: the latter is obtained from the former by taking a trace over the degrees of freedom that are not those of this body/brain. The fact that the conscious experiences associated with one person's body/brain cannot directly access, or know, the conscious experiences associated with another person's body/braim is called the subjectiveness, or subjective property, of these experiences. But the reduction of S associated with a person's experience is an objective change in S. The vN/W interpretation is an ontologicalization of the Copenhagen interpretation. In vN/W the entire physical universe is represented quantum mechanically. The whole quantum formalism is simply taken over intact, the only difference being that in the vN/W interpretation the projection operator P associated with a person's experience E acts on the degrees of freedom of that person's body/brain: P picks out the states that contain the "neural correlates of the conscious experience E". In the Copenhagen interpretation this projection operator acts rather on the degrees of freedom of a system that has been probed by an instrument that is being examined by that person. The equivalence, in good measurement situations, of the predictions via these two formulations is what von Neumann's analysis showed. So although the two interpretations are pragmatically equivalent in these good measurement situations, and are hence empirically indistinguishable within that context, the two interpretations are logically and metaphysically very different. The Copenhagen separates the physical world into parts that are treated differently, whereas the vN/W treats the entire physical world quantum mechanically. Moreover, the Copenhagen interpretation is based on a long-distance direct connection between the observer's experience and some external-to-his-body system that has been probed by an instrument that he is observing, whereas the vN/W interpretation connects a person's experience directly to the neural correlate of that experience. This is the connection that is directly appropriate to the huge body of experimental work currently being done to probes directly the mind-brain connection. The mathematical forms that lie behind these words are illustrated in my recent posting of Theory of Presponse and Stapp's Knowledge (Mar 2). Notice that these forms are exactly those of Copenhagen quantum theory. In accordance with the Copenhagen principles, nothing ent%ers the computations except the quantum mechanical representations of physical systems (i.e., in terms of operators) and the quantum mechanical representations of the possible experiences that the computations are about. The only difference is that in vN/W theory the operator P corresponding to a person's experience acts on the variables associated with that person's brain/body, and picks out the neural correlates of that experience. That change seems like a reasonable thing to try, if one is studying the mind-brain connection.