%REPORTMASTER (revised 8/24/88) \documentstyle[12pt]{article} %\input math_macros.tex \def\baselinestretch{1.2} \def\thefootnote{\fnsymbol{footnote}} \begin{document} \begin{titlepage} \noindent March 8, 2001 \hfill LBNL-44712 \noindent[To appear in Foundations of Physics] \vskip .5in \noindent{\large \bf QUANTUM THEORY AND THE\\ ROLE OF MIND IN NATURE} \footnote{This work is supported in part by the Director, Office of Science, Office of High Energy and Nuclear Physics, Division of High Energy Physics, of the U.S. Department of Energy under Contract DE-AC03-76SF00098} \vskip .20in \noindent \hspace*{1.0in} {\bf Henry P. Stapp}\\ \hspace*{1.0in} Lawrence Berkeley National Laboratory\\ \hspace*{1.0in} University of California\\ \hspace*{1.0in} Berkeley, California 94720\\ \hspace*{1.0in} hpstapp@lbl.gov \vskip .7 in \noindent Orthodox Copenhagen quantum theory renounces the quest to understand the reality in which we are imbedded, and settles for practical rules describing connections between our observations. Many physicist have regarded this renunciation of our effort to describe nature herself as premature, and John von Neumann reformulated quantum theory as a theory of an evolving objective universe interacting with human consciousness. This interaction is associated both in Copenhagen quantum theory and in von Neumann quantum theory with a sudden change that brings the objective physical state of a system in line with a subjectively felt psychical reality. The objective physical state is thereby converted from a material substrate to an informational and dispositional substrate that carries both the information incorporated into it by the psychical realities, and certain dispositions for the occurrence of future psychical realities. The present work examines and proposes solutions to two problems that have appeared to block the development of this conception of nature. The first problem is how to reconcile this theory with the principles of relativistic quantum field theory; the second problem is to understand whether, strictly within quantum theory, a person's mind can affect the activities of his brain, and if so how. Solving the first problem involves resolving a certain nonlocality question. The proposed solution to the second problem is based on a postulated connection between effort, attention, and the quantum Zeno effect. This solution explains on the basis of quantum physics a large amount of heretofore unexplained data amassed by psychologists. \end{titlepage} \newpage \renewcommand{\thepage}{\arabic{page}} \setcounter{page}{1} %THIS IS PAGE 1 (INSERT TEXT OF REPORT HERE) \noindent {\bf 1. THE NONLOCALITY QUESTION}\\ \noindent ``Nonlocality gets more real''. This is the provocative title of a recent report in Physics Today [1]. Three experiments are cited. All three confirm to high accuracy the predictions of quantum theory in experiments that suggest the occurrence of an instantaneous action over a large distance. The most spectacular of the three experiments begins with the production of pairs of photons in a lab in downtown Geneva. For some of these pairs, one member is sent by optical fiber to the village of Bellevue, while the other is sent to the town of Bernex. The two towns lie more than 10 kilometers apart. Experiments on the arriving photons are performed in both villages at essentially the same time. What is found is this: The observed connections between the outcomes of these experiments defy explanation in terms of ordinary ideas about the nature of the physical world {\it on the scale of directly observable objects.} This conclusion is announced in opening sentence of the Physical-Review-Letters report [2] that describes the experiment: ``Quantum theory is nonlocal''. This observed effect is not just an academic matter. A possible application of interest to the Swiss is this: The effect can be used in principle to transfer banking records over large distances in a secure way [3]. But of far greater importance to physicists is its relevance to two fundamental questions: What is the nature of physical reality? What is the form of basic physical theory? The answers to these questions depend crucially on the nature of physical causation. Isaac Newton erected his theory of gravity on the idea of instant action at a distance. According to Newton's theory, if a person were to suddenly kick a stone, and send it flying off in some direction, every particle in the entire universe would {\it immediately} begin to feel the effect of that kick. Thus, in Newton's theory, every part of the universe is instantly linked, causally, to every other part. To even think about such an instantaneous action one needs the idea of the instant of time ``now'', and a sequence of such instants each extending over the entire universe. This idea that what a person does in one place could act instantly affect physical reality in a faraway place is a mind-boggling notion, and it was banished from classical physics by Einstein's theory of relativity. But the idea resurfaced at the quantum level in the debate between Einstein and Bohr. Einstein objected to the ``mysterious action at a distance'', which quantum theory seemed to entail, but Bohr defended ``the necessity of a final renunciation of the classical ideal of causality and a radical revision of our attitude towards the problem of physical reality''[4]. The essence of this radical revision was explained by Dirac at the 1927 Solvay conference [5]. He insisted on the restriction of the application of quantum theory to our knowledge of a system, rather than to the system itself. Thus physical theory became converted from a theory about `physically reality', as it had formerly been understood, into a theory about human knowledge. This view is encapsulated in Heisenberg's famous statement [6]: ``The conception of the objective reality of the elementary particles has thus evaporated not into the cloud of some obscure new reality concept, but into the transparent clarity of a mathematics that represents no longer the behaviour of the particle but rather our knowledge of this behaviour.'' This conception of quantum theory, espoused by Bohr, Dirac, and Heisenberg, is called the Copenhagen interpretation. It is essentially subjective and epistemological, because the basic reality of the theory is `our knowledge'. It is certainly true that science rests ultimately on what we know. That fact is the basis of the new point of view. However, the tremendous successes of the classical physical theory inaugurated by Galileo, Descartes, and Newton during the seventeenth century, had raised the hope and expectation that human beings could extract from careful observation, and the imaginative creation of testable hypotheses, a valid idea of the general nature, and rules of behaviour, of the reality in which our human knowledge is imbedded. Giving up on that hope is indeed a radical shift. On the other hand, classical physical theory left part of reality out, namely our conscious experiences. Hence it had no way to account either for the existence of our conscious experiences or for how knowledge can reside in those experiences. Thus bringing human experience into our understanding of reality would seem to be a step in the right direction. It might allow science to explain, eventually, how we know what we know. But Copenhagen quantum theory is only a half-way house: it brings in human experience, but at the stiff price of excluding the rest of reality. Yet how could the renowned scientists who created Copenhagen quantum theory ever believe, and sway most other physicists into believing, that a complete science could leave out the physical world? It is undeniable that we can never know for sure that a proposed theory of the world around us is really true. But that is not a sufficient reason to renounce, as a matter of principle, even the attempt to form a coherent idea of what the world {\it could} be like, and rules by which it {\it could} work. Clearly some extraordinarily powerful consideration was in play. That powerful consideration was a basic idea about the nature of physical causation that had been injected into physics by Einstein's theory of relativity. That idea was not working! The problem is this. Quantum theory often entails that an act of acquiring knowledge in one place instantly changes the theoretical representation of some faraway system. Physicists were---and are---reluctant to believe that performing a nearby act can instantly change a faraway physical reality. However, they recognize that ``our knowledge'' of a faraway system can instantly change when we learn something about a nearby system. In particular, if certain properties of two systems are known to be strongly correlated, then finding out something about one system can tell us something about the other. For example, if we know that two particles start from some known point at the same time, and then move away from that point at the same speeds, but in opposite directions, then finding one of these particles at a certain point allows us to `know' where the other particle lies at that same instant: it must lie at the same distance from the starting point as the observed particle, but in the opposite direction. In this simple case we do not think that the act of observing the position of one particle {\it causes} the other particle to {\it be} where it is. We realize that it is only our knowledge of the faraway system that has changed. This analogy allows us resolve, by fiat, any mystery about an instantaneous faraway effect of a nearby act: if something faraway can instantly be altered by a nearby act then it {\it must be} our knowledge. But then the analog in quantum theory of the physical reality of classical physical theory {\it must be} our knowledge. This way of dodging the action-at-a-distance problem was challenged by Einstein, Podolsky, and Rosen in a famous paper [7] entitled: ``Can quantum-mechanical description of physical reality be considered complete?'' The issue was whether a theory that is specified to be merely a set of rules about connections between human experiences can be considered to be a complete description of physical reality. Einstein and his colleagues gave a reasonable definition of ``physical reality'', and then argued, directly from some basic precepts of quantum theory itself, that the answer to this question is `No'. Bohr [8] disagreed. Given the enormity of what must exist in the universe as a whole, and the relative smallness human knowledge, it is astonishing that, in the minds of most physicists, Bohr prevailed over Einstein in this debate: the majority of quantum physicists acquiesced to Bohr's claim that quantum theory, regarded as a theory about human knowledge, is a complete description of physical reality. This majority opinion stems, I believe, more from the lack of a promising alternative candidate than from any decisive logical argument. Einstein, commenting on the orthodox Copenhagen position, said: ``What I dislike about this kind of argument is the basic positivistic attitude, which from my view is untenable, and seems to me to come to the same thing as Berkeley's principle [9], {\it esse est percipi},'' `to be is to be perceived'. Several other scientists also reject the majority opinion. For example, Murray Gell-Mann [10] asserts: ``Niels Bohr brainwashed a whole generation into believing that the problem was solved fifty years ago''. Gell-mann believes that in order to integrate quantum theory coherently into cosmology, and to understand the evolutionary process that has produced creatures that can have knowledge, one needs to have a coherent theory of the evolving quantum mechanical reality in which these creatures are imbedded. It is in the context of such efforts to construct a more complete theory that the significance of the experiments pertaining to quantum nonlocality lies. The point is this: If nature really is nonlocal, as these experiments seem to suggest, then the way is open to the development of a rationally coherent theory of nature that integrates the subjective knowings introduced by Copenhagen quantum theory into an objectively existing and evolving physical reality. The basic framework is provided by the version of quantum theory constructed by John von Neumann [11] All physical theories are, of course, provisional, and subject to future revision and elaboration. But at a given stage in the development of science the contending theories can be evaluated on many grounds, such as utility, parsimony, predictive power, explanatory power, conceptual simplicity, logical coherence, and aesthetic beauty. The development of von Neumann's theory that I shall describe here fares well on all of these counts. To understand von Neumann's improvement one must appreciate the problems with its predecessor. Copenhagen quantum theory gives special status to measuring devices. These devices are physical systems: they are made up of atomic constituents. But in spite of this, these devices are excluded from the world of atomic constituents that are described in the mathematical language of quantum theory. The measuring devices, are described, instead, in a different language, namely by ``the same means of communication as the one used in classical physics'' [12]. This approach renders the theory pragmatically useful but physically incoherent. It links the theory to ``our knowledge'' of the measuring devices in a useful way, but disrupts the dynamical unity of the physical world by treating in different ways different atomic particles that are interacting with each other. This tearing apart of the physical world creates huge conceptual problems, which are ducked in the Copenhagen approach by renouncing man's ability to understand reality. The Copenhagen version of quantum theory is thus a hybrid of the old familiar classical theory, which physicists were understandably reluctant to abandon completely, and a totally new theory based on radically different concepts. The old ideas, concepts, and language were used to describe our experiences, but the old idea that the visible objects were made up of tiny material objects resembling miniature planets, or minute rocks, was dropped. The observed physical world is described rather by a mathematical structure that can best be characterized as representing {\it information} and {\it propensities}: the {\it information} is about certain {\it events} that have occurred in the past, and the {\it propensities} are objective tendencies pertaining to future events. These ``events'' are the focal point of quantum theory: they are happenings that in the Copenhagen approach are ambiguously associated both with the ``measuring devices'' and with increments in the knowledge of the observers who are examining these devices. Each increment of knowledge is an event that updates the knowledge of the observers by bringing it in line with the observed outcome of an event occurring at a device. The agreement between the event at the device and the event in the mind of the observer is to be understood in the same way as it is understood in classical physics. But there's the rub: the connection between human knowledge and the physical world never has been understood in classical physics. The seventeenth century division between mind and matter upon which classical physically theory was erected was such a perfect cleavage that no reconciliation has ever been achieved, in spite of tremendous efforts. Nor is such a reconciliation possible within classical physics. According to that theory, the world of matter is built out of microscopic entities whose behaviours are fixed by interaction with their immediate neighbors. Nothing need exist except what can be deduced in principle, by using only the precepts of classical physical theory, from the existence of these microscopic building blocks. But the defining characteristic of consciousness, namely its experiential quality, is not deducible from these elements of classical physical theory, and that is all that classical physical theory entails. The fact that quantum theory is intrinsically a theory of mind-matter interaction was not lost upon the early founders and workers. Wolfgang Pauli [13], John von Neumann [14], and Eugene Wigner [15] were three of the most rigorous thinkers of that time. They all recognized that quantum theory was about the mind-brain connection, and they tried to develop that idea. However, most physicists were more interested in experiments on relatively simple atomic systems, and were understandably reluctant to get sucked into the huge question of the connection between mind and brain. They were willing to sacrifice certain formerly-held ideals, and take practical success to be the basic criterion of good science. This retreat both buttressed, and was buttressed by, two of the main philosophical movements of the twentieth century. One of these, materialism-behaviourism, effectively denied the existence of our conscious ``inner lives'', and the other, logical positivism and variants thereof (eg. Mack's sensationalism and pragmatism, Russell's phenomenalism, and Bridgeman's operationalism) brought the activities of scientists more centrally into our conception of the nature of the scientific endeavour, without, however, trying to face head-on the basic issue of how our thoughts can affect our actions. The time was not yet ripe, either philosophically or scientifically, for a serious attempt to study the physics of mind-matter connection. Today, however, as we enter the third millenium, there is a huge surge of interest among philosophers, psychologists, and neuroscientists in reconnecting the aspects of nature that were torn asunder by seventeenth century physicists. John von Neumann was one of the most brilliant mathematicians and logicians of his age. He followed where the mathematics and logic led. From the point of view of the mathematics of quantum theory it makes no sense to treat a measuring device as intrisically different from the collection of atomic constituents that make it up. A device is just another part of the physical universe, and it should be treated as such. Moreover, the conscious thoughts of a human observer ought to be causally connected {\it most directly and immediately} to what is happening in his brain, not to what is happening out at some measuring device. The mathematical rules of quantum theory specify clearly how the measuring devices are to be included in the quantum mechanically described physical world. Von Neumann first formulated carefully the mathematical rules of quantum theory, and then followed where that mathematics led. It led first to the incorporation of the measuring devices into the quantum mechanically described physical universe, and eventually to the inclusion of {\it everything} built out of atoms and their constituents. Our bodies and brains thus become, in von Neumann's approach, parts of the quantum mechanically described physical universe. Treating the entire physical universe in this unified way provides a conceptually simple and logically coherent theoretical foundation that heals the rupturing of the physical world introduced by the Copenhagen approach. It postulates, for each observer, that each experiential event is connected in a certain specified way to a corresponding brain event. The dynamical rules that connect mind and brain are very restrictive, and this leads to a mind-brain theory with significant explanatory power. Von Neumann showed in principle how all of the predictions of Copenhagen quantum theory are contained in his version. However, von Neumann quantum theory gives, in principle, much more than Copenhagen quantum theory can. By providing an objective description of the entire history of the universe, rather than merely rules connecting human observations, von Neumann's theory provides a quantum framework for cosmological and biological evolution. And by including both brain and knowledge, and also the dynamical laws that connect them, the theory provides a rationally coherent dynamical framework for understanding the relationship between brain and mind. There are, however, two major obstacles to the pursuit of von Neumann's approach to the problem of integrating mind into physical theory. The first is that he formulated it in a nonrelativistic approximation that does not explicitly satisfy the constraints imposed by Einstein's theory of relativity. I shall discuss this problem first.\\ \\ \noindent {\bf 2. RECONCILIATION WITH RELATIVITY}\\ \noindent To deal with the mind-brain interaction one needs to consider the physical processes in human brains. The relevant quantum field theory is quantum-elecrodynamics. The relevant energy range is that of atomic and molecular interactions. I shall assume that whatever high-energy theory eventually prevails in quantum physics, it will reduce to quantum electrodynamics in this low-energy regime. Von Neumann formulated his theory in a nonrelativistic approximation: he made no attempt to reconcile it with the empirically validated features of Einstein's theory of relativity. In particular von Neumann's nonrelativistic formulation of quantum theory is built on the Newtonian concept of the instants of time, `now', each of which extends over all space. The evolving state of the universe, $S(t)$, is defined to be the state of the entire universe at the instant of time t. However, Einstein's theory of relativity rejected, at least for the classical physical theory that it was originally designed to cover, the idea that the Newtonian concept of the instant ``now'' could have any objective meaning. This apparent problem is easily resolved in principle. Tomonaga [16] and Schwinger [17] have constructed a standard formulation of relativistic quantum field theory. It has effective instants ``now'', namely the Tomonaga-Schwinger surfaces $\sigma $. Pauli once strongly emphasized to me that these surfaces, while they give a certain aura of relativistic invariance, do not differ significantly from the constant-time surfaces ``now'' that appear in the Newtonian physics. To obtain a relativistic version of von Neumann's theory one need merely identify the sequence of constant-time surfaces ``now'' in his theory with some particular objectively defined sequence of Tomonaga-Schwinger surfaces $\sigma $. Giving special objective physical status to a particular sequence of spacelike surfaces $\sigma$, say the constant-time surfaces in some one particular Lorentz frame, does not disrupt the covariance properties of the {\it empirical predictions} of the theory: that was one of the main consequences of the Tomonoga-Schwinger formulation. Although each reduction of the state vector in T-S theory must be taken to occur instantaneously along one of the preferred set of surfaces $\sigma$ the predictions about observations remain independent of {\it which} sequence of surfaces $\sigma$ is chosen (e.g., which Lorentz frame is used to define the preferred sequence of surfaces). Thus this relativistic version of von Neumann's theory is fully compatible with the theory of relativity at the level of empirically accessible relationships. However, the theory does conflict with a {\it metaphysical idea} spawned by the theory of relativity, namely the idea that there is no dynamically preferred sequence of instantaneous ``nows''. Thus the theory reverts, at a certain deep unobservable ontological level, to the Newtonian idea of ``instantaneous'' ---along one of the preferred surfaces--- action at a distance, while maintaining all of the empirical demands of the theory of relativity. The astronomical data [18] indicates that there does exist, in the observed universe, a preferred sequence of `nows': they consist of the special set of surfaces in which the cosmic background radiation is isotropic. It is natural to assume that these empirically specified surfaces are the same as the objective preferred surfaces ``now'' of von Neumann quantum theory. \\ \\ \noindent {\bf 3. NONLOCALITY AND RELATIVITY}\\ \noindent von Neumann's objective theory immediately accounts for the faster-than-light transfer of information whose existence is suggested by the nonlocality experiments: the outcome that appears first, in the cited experiment, occurs in one or the other of the two Swiss villages. According to the theory, this earlier event has an immediate instantaneous effect on the evolving state of the universe, and this change has an immediate effect on the {\it propensities} for the various possible outcomes of the measurement performed slightly later in the other village. This feature---that there is some sort of objective instantaneous transfer of information---conflicts with the spirit of the theory of relativity. However, this quantum effect is of a subtle kind: it acts neither on material substance, nor on locally conserved energy-momentum, nor on anything else that exists in the classical conception of the physical world that the theory of relativity was originally designed to cover. It acts on a mathematical structure that represents, rather, {\it information and propensities}. The theory of relativity was originally formulated within classical physical theory. This is a deterministic theory: the entire history of the universe is completely determined by how things start out. Hence all of history can be conceived to be laid out in a four-dimensional spacetime. The idea of ``becoming'', or of the gradual unfolding of reality, has no natural place in this deterministic conception of the universe. Quantum theory is a different kind of theory: it is formulated as an indeterministic theory. Determinism is relaxed in two important ways. First, freedom is granted to each experimenter to choose freely which experiment he will perform, i.e., which aspect of nature he will probe; which question he will put to nature. Then Nature is allowed to pick an outcome of the experiment, i.e., to answer to the question. This answer is partially free: it is subject only to certain statistical requirements. These elements of `freedom of choice', on the part of both the human participant and Nature herself, lead to a picture of a reality that gradually unfolds in response to choices that are not necessarily fixed by the prior physical part of reality alone. The central roles in quantum theory of these discrete choices--- the choices of which questions will be put to nature, and which answer nature delivers---makes quantum theory a theory of discrete events, rather than a theory of the continuous evolution of locally conserved matter/energy. The basic building blocks of the new conception of nature are not objective tiny bits of matter, but choices of questions and answers. In view of these deep structural differences there is a question of principle regarding how the stipulation that there can be no faster-than-light transfer of information of any kind should be carried over from the invalid deterministic classical theory to its indeterministic quantum successor. The theoretical advantages of relaxing this condition are great: it provides an immediate resolution all of the causality puzzles that have blocked attempts to understand physical reality, and that have led directly to the Copenhagen renunciation of all such efforts. And it provides a mathematical description of an evolving objective physical world that interacts in specified ways with a psychical aspect of reality that manifests itself in human beings as our conscious thoughts and feelings. In view of these potential advantages one must ask whether it is really beneficial for scientists to renounce for all time the aim of trying to understand the world in which we live, in order to maintain a metaphysical prejudice that arose from a theory that is known to be fundamentally incorrect? I use the term ``metaphysical prejudice'' because there is no theoretical or empirical evidence that supports the non-existence of the subtle sort of instantaneous action that is involved here. Indeed, both theory and the nonlocality experiments, taken at face value, seem to demand it. The denial of the possibility of any such action is a metaphysical commitment that was useful in the context of classical physical theory. But that earlier theory contains no counterpart of the informational structure upon which the putative action in question acts. Renouncing the endeavour to understand nature is a price too heavy to pay to preserve a metaphysical prejudice.\\ \\ \noindent {\bf 4. TOMONOGA-SCHWINGER NONLOCALITY?}\\ \noindent In the Tomonoga-Schwinger formulation of quantum field theory all of the alternative possible advancing sequences of surfaces sigma are empirically equivalent: the predicted connections between observations does not depend on which one of the infinite set advancing sequence is used. Thus it seems reasonable to deny reality to all of them, and, by extension, to deny reality to the faster-than-light transfer of information that, according to the theory, needs to be conveyed by at least one of them, in order to account for the data. But that logical is not very compelling: it is true that the theory does not specify which one of the advancing sequence should be used; it does not specify exactly how the tranfer occurs. But no matter which sequence is chosen, {\it some} faster-than-light transfer will occur in a typical ERP correlation experiment, within the T-S description. This seemingly clear consequence of the T-S theory, namely that relativistic quantum field theory does involve, at some basic level, faster-than-light transfer of information, can be resisted by declaring that the mathematical constructs that appear in T-S theory are not to be construed realistically. Indeed, the fact that those constructs lead to this ``obviously false'' conclusion is precisely the basis for making that declaration. That way of evading the issue leads to the question of whether the need for such transfers of information can be proved directly from the predictions of the theory themselves, and other general properties that can be deduced directly from the theory, without giving any ontological status to states or wave functions. If the need for faster-than-light transfers can be proved in this more general way then it becomes reasonable to introduce the surfaces along which the needed transfers occur, and then to construe the Tomonoga-Schwinger-von Neumann description ontologically.\\ \\ \noindent {\bf 5. IS NONLOCALITY REAL?}\\ \noindent I began this article with the quote from Physics Today: ``Nonlocality gets more real.'' The article described experiments whose outcomes were interpreted by the experimenters who did the experiment as empirical evidence that nature was nonlocal. But do nonlocality experiments of this kind provide any real evidence that information is actually transferred over spacelike intervals? An affirmative answer to this question would provide support for rejecting the metaphysical prejudice about faster-than-light influences,, and accepting the T-S-VN formulation of quantum field theory described above. The evidence is very strong that the predictions of quantum theory are valid in these experiments involving pairs of measurements performed at essentially the same time in regions lying far apart. But the question is this: Does the fact that the predictions of quantum theory are correct in experiments of this kind actually show that information must be transferred over spacelike intervals? The usual arguments that connect these experiments to nonlocal action stem from the work of John Bell [19]. What Bell did was this. He noted that the argument of Einstein, Podolsky, and Rosen was based on a certain assumption, namely that ``Physical Reality'', whatever it was, should have at least one key property: What is physically real in one region should not depend upon which experiment an experimenter in a faraway region freely chooses to do at essentially the same instant of time. Einstein and his collaborators showed that if this property is valid then the physical reality in a certain region must include, or specify, the values that certain unperformed measurements {\it would have revealed} if they, rather than the actually performed measurements, had been performed. However, Copenhagen quantum theory cannot accommodate well defined outcomes of these not-actually-performed measurements. Thus the Einstein-Podilsky-Rosen argument, if correct, would prove that the quantum framework cannot be a complete description of physical reality. Bohr countered this argument by rejecting the claimed key property of physical reality: he denied the claim pertaining to no instantaneous action at a distance. That rebuttal is subtle, and many physicists (e.g. Einstein and John Bell) and philosophers (e.g. Karl Popper) doubted that Bohr had successfully answered the EPR argument. Bell found a more direct way to counter the argument of Einstein, Podolsky, and Rosen. He accepted both their claim that the results of these {it unperformed measurements} are indeed physically real, and that these physical realities could not be influenced by what far-away experimenters choose to measure at essentially the same instant of time. And he assumed, as did all the disputants, that the {\it predictions} of quantum theory were correct. From these assumptions Bell deduced a mathematical contradiction, thereby showing that {\it something} must be wrong with either the conclusions of Einstein, Podolsky, and Rosen, or with the no-faster-than-light-influence assumption. But Bell's argument did not fixed exactly where the trouble lies. Does the trouble lie with the assumption of no faster-than-light influence, or with the EPR conclusion that the outcomes of certain unperformed measurements are physically real? Orthodox quantum theorists have no trouble answering this question: the {\it assumption} that outcomes of unperformed measurements are physically real is wrong. That idea directly contradicts quantum philosophy! This answer allows one to retain Einstein's reasonable-sounding assumption that physical reality in one place cannot be influenced by what a faraway experimenter freely chooses to do at the same instant: Bell's argument neither entails, nor even really suggests, the existence of faster-than-light influences. Bell, and others who followed his ``hidden-variable'' approach [19], later used assumptions that appear weaker than this original one, and that cover certain inherently stochastic models that obey a hidden-variable factorization property that enforces a certain locality condition. However, these later assumptions turn out to entail [20, 21] the possibility of specifying, simultaneously, numbers that {\it could be} the values that all the relevant unperformed measurements would reveal if they were to be performed. I believe that one of the basic ideas of quantum philosophy, is that one should not assume, either explicity or implicitly, the existence of numbers that could specify, in a manner consistent with all the predictions of quantum theory, possible values for the outcomes of all of the performed and unperformed experiments. The stochastic hidden-variable theorems violate this strong construal of a precept of quantum philosophy. I shall present now an alternative nonlocalty result that is based on assumptions that appear to be in line with orthodox quantum thinking.\\ \\ \noindent {\bf 6. ELIMINATING HIDDEN VARIABLES}\\ \noindent The purpose of Bell's argument is different from that of Einstein, Podolsky, and Rosen, and the logical demands are different. The challenge faced by Einstein and his colleagues was to mount an argument built directly on the orthodox quantum principles themselves. For only by proceeding in this way could they get a logical hook on the quantum physicists that they wanted to convince. This demand posed a serious problem for Einstein and co-workers. Their argument, like Bell's, involved a consideration of the values that unperformed measurements would reveal if they were to be performed. Indeed, it was precisely the Copenhagen claim that such values do not exist that Einstein and company wanted to prove untenable. But they needed to establish the existence of such values without begging the question by making an assumption that was equivalent to what the were trying to show. The strategy of Einstein et. al. was to prove the existence of such values by using only quantum precepts themselves, plus the seemingly secure idea from the theory of relativity that what is physically real here and now cannot be influenced by what a faraway experimenter chooses to do now. This strategy succeeded: Bohr was forced into an awkward position of rejecting Einstein's premise that ``physical reality'' could not be influenced by what a faraway experimenter chooses to do: ``...there is essentally the question of {\it an influence on the very conditions which define the possible types of predictions regarding future behavior of the system.} Since these conditions constitute an inherent element of any phenomena to which the term `physically reality' can be properly attached we see that the argument of mentioned authors does not justify their conclusion that quantum-mechanical description is essentially incomplete.''[8] I shall pursue here a strategy similar to that of Einstein and his colleagues, and will be led to a conclusion similar to Bohr's, namely the failure of Einstein's assumption that physical reality cannot be influenced from afar. Values of unperformed measurements can be brought into the theoretical analysis by combining two ideas that are embraced by Copenhagen philosophy. The first of these is the freedom of experimenters to choose which measurements they will perform. In Bohr's words: ``The freedom of experimentation, presupposed in classical physics, is of course retained and corresponds to the free choice of experimental arrangements for which the mathematical structure of the quantum mechanical formalism offers the appropriate latitude.''[21] This assumption is important for Bohr's notion of complementarity: some information about all the possible choices is simultaneously present in the quantum state, and Bohr wanted to provide the possibility that any one of the mutually exclusive alternatives might be pertinent. Whichever choice the experimenter eventually makes, the associated set of predictions is assumed to hold. The second idea is the condition of no backward-in-time causation. According to quantum thinking, experimenters are to be considered free to choose which measurement they will perform. Moreover, if an outcome of a measurement appears to an observer at a time earlier than some time $T$, then this outcome can be considered to be fixed and settled at that time $T$, independently of which experiment will be {\it freely chosen} and performed by another experimenter at a time later than $T$: the later choice is allowed go either way without disturbing the outcome that has already appeared to observers at an earlier time. I shall make the {\it weak} assumption that this no-backward-in-time-influence condition holds for {\it at least one} coordinate system (x,y,z,t). These two conditions are, I believe, completely compatible with quantum thinking, and are a normal part of orthodox quantum thinking. They contradict no quantum precept or combination of quantum predictions. They, by themselves, lead to no contradiction. (This can be proved by an examination of the T-S formulation.) But they do introduce into the theoretical framework a very limited notion of a result of an unperformed measurement, namely the result of a measurement that is actually performed in one region at an earlier time $T$ coupled with the measurment NOT performed {\it later} by some faraway experimenter. My assumption is that this early outcome, which is actually observered by someone, can be treated as existing independently of which of the two alternative choices is made by the experimenter in the later region, even though only one of the two later options can be realized. This assumption of no influence backward in time yields the small element of counterfactuality that provides the needed logical toe-hold.\\ \\ \noindent {\bf 7. THE HARDY EXPERIMENTAL SET UP}\\ \noindent To get a nonlocality conclusion like the one obtained from Bell-type theorems, but from assumptions that are in line with the precepts of quantum theory, it is easiest to consider an experiment of the kind first discussed by Lucien Hardy [23]. The setup is basically similar to the ones considered in proofs of Bell's theorem. There are two spacetime regions, L and R, that are ``spacelike separated''. This condition means that the two regions are situated far apart in space relative to their extensions in time, so that no point in either region can be reached from any point in the other without moving either faster than the speed of light or backward in time. This means also that in some frame of reference, which I take to be the coordinate system (x,y,z,t) mentioned above, the region L lies at times greater than time $T$, and the region R lies earlier than time $T$. In each region an experimenter freely chooses between two possible experiments. Each experiment will, if chosen, be performed within that region, and its outcome will appear to observers within that region. Thus neither choice can affect anything located in the other region without there being some influence that acts faster than the speed of light or backward in time. The argument involves four predictions made by quantum theory under the Hardy conditions. These conditions and predictions are described in Box 1. -------------------------------------------------------------------- {\bf Box 1: Predictions of quantum theory for the Hardy experiment.} The two possible experiments in region L are labelled L1 and L2. The two possible experiments in region R are labelled R1 and R2. The two possible outcomes of L1 are labelled L1+ and L1-, etc. The Hardy setup involves a laser down-conversion source that emits a pair of correlated photons. The experimental conditions are such that quantum theory makes the following four predictions:\\ \\ 1. If (L1,R2) is performed and L1- appears in L then R2+ must appear in R.\\ 2. If (L2,R2) is performed and R2+ appears in R then L2+ must appear in L.\\ 3. If (L2,R1) is performed and L2+ appears in L then R1- must appear in R.\\ 4. If (L1,R1) is performed and L1- appears in L then R1+ appears sometimes in R.\\ The three words ``must'' mean that the specified outcome is predicted to occur with certainty (i.e., probability unity). --------------------------------------------------------------------------- \\ \\ \noindent {\bf 8. TWO SIMPLE CONCLUSIONS}\\ \noindent It is easy to deduce from our assumptions two simple conclusions. Recall that region R lies earlier than time $T$, and that region L lies later than time $T$. Suppose the actually selected pair of experiments is (R2, L1), and that the outcome L1- appears in region L. Then prediction 1 of quantum theory entails that R2+ must have already appeared in R prior to time $T$. The no-backward-in-time-influence condition then entails that this outcome R2+ was fixed and settled prior to time $T$, independently of which way the later free choice in L will eventually go: the outcome in region R at the earlier time would still be R2+ even if the later free choice had gone the other way, and L2 had been chosen {\it instead of} L1. Under this alternative condition (L2,R2,R2+) the experiment L1 would not be performed, and there would be no physical reality corresponding to its outcome. But the actual outcome in R would still be R2+, and we are assuming that the predictions of quantum theory will hold no matter which of the two experiments is eventually performed later in L. Prediction 2 of quantum theory asserts that it must be L2+. This yields the following conclusion: Assertion A(R2): If (R2,L1) is performed and outcome L1- appears in region L, then if the choice in L had gone the other way, and L2, instead of L1, had been performed in L then outcome L2+ would have appeared there. Because we have two predictions that hold with certainty, and the two strong assumptions of `free choice' and `no backward causation', it is not surprising that we have been able to derive this conclusion. In an essentially deterministic context we are often able to deduce from the outcome of one measurement what would have happened if we had made, instead, another measurement. Indeed, if knowing the later {\it actual} outcome allows one to know what some earlier condition must have been, and if this earlier condition entails a unique result of the later {\it alternative} measurement, then one can conclude from knowledge of the later {\it actual} outcome what would have happened if, instead, the later {\it alternative} measurement had been performed. This is about the simplest possible example of counterfactual reasoning. Consider next the same assertion, but with R2 replaced by R1: Assertion A(R1): If (R1,L1) is performed and outcome L1- appears in region L, then if the choice in L had gone the other way, and L2, instead of L1, had been performed in L then outcome L2+ would have appeared there. This assertion cannot be true. The fourth prediction of quantum theory asserts that under the specified conditions L1- and R1 the outcome R1+ sometimes appears in R. The no-backward-in-time-influence condition ensures that this earlier appearance of R1+ would not be altered if the later choice in region L had gone the other way and L2 had been chosen there: that is our basic causality assumption. But A(R1) asserts that under this condition that L2 is performed later the outcome L2+ must appear in L. But if L2+ were to occur under this condition (L2,R1) then the third prediction entails that then R1- must appear in R. That conclusion contradicts the previously established result that under these conditions R1+ sometimes appears in R. Thus, given the validity of the four predictions of quantum theory, and of our basic causality condition, the validity of assertion A(R1) cannot be maintained. The fact that A(R2) is true and A(R1) is false entails a certain nonlocal connection. The truth of the first of these statements means that certain assumptions that are {\it compatible} with quantum philosophy, and that probably are {\it parts} of quantum philosophy, as it is understood by most quantum physicists, entail a connection of the following form: ``If experiment E1 is performed in region L and gives outcome O1 in region L then if, instead, experiment E2 had been performed in region L the outcome in region L would have been O2.'' This result is similar to what Einstein, Podolsky, and Rosen tried to prove, but is weaker, because it does not claim that the two outcomes exist simultaneously. However, it is derived from weaker assumptions: it is not based on the criterion for ``Physical Reality'' that Einstein, Podolsky, and Rosen used, but Bohr rejected. This weaker conclusion, alone, does not directly contradict any precept of quantum philosophy. But the {\it conjunction} of the two statements, ``A(R2) is true and A(R1) is false'' leads to a problem. It asserts that a theoretical constraint upon what nature can choose in region L, under conditions freely chosen by the experimenter in region L, depends nontrivially on which experiment is freely chosen by the experimenter in regions R: a theoretical constraint on Nature's choices in L depends upon what a faraway experimenter freely decides to do in R. Any theoretical model that is compatible with the premises of the argument would have to maintain these theoretical constraints on nature's choices in region L, and hence enforce the nontrivial dependence of these constraints on the free choice made in region R. But this dependence cannot be upheld without the information about the free choice made in region R getting to region L: {\it some sort of faster-than-light tranfer of information is required.} This conclusion does not cover Everett-type theories, which reject at the outset the fundamental idea used here that definite outcomes actually occur. This nonlocality theorem buttresses the critical assumption of the objective interpretation von Neumann's formulation of quantum theory that is being developed here, namely the assumption that there is a preferred set of successive instants ``now'' associated with the evolving objective quantum state of the universe, and that the reduction process acts instantly along these surfaces. This assumption is completely compatible with the relativistic covariance of all the {\it predictions} of relativistic quantum field theory: that is demonstrated by the Tomonaga-Schwinger formulation of relativistic quantum field theory [16,17]. A close scutiny of an earlier version of the nonlocality argument described here can be found in exchange between this author and Abner Shimony and Howard Stein that will appear in the American Journal of Physics. [24,25] \\ \\ \noindent {\bf 9. THE PHYSICAL WORLD AS INFORMATION}\\ \noindent Von Neumann quantum theory is designed to yield all the predictions of Copenhagen quantum theory. It must therefore encompass the increments of knowledge that Copenhagen quantum theory makes predictions about. Von Neumann's theory is, in fact, essentially a theory of the interaction of these subjective realities with an evolving objective physical universe. Von Neumann makes clear the fact that he is trying to tie together the subjective perceptual and objective physical aspects of nature: ``it is inherently entirely correct that the measurement or related process of subjective perception is a new entity relative to the physical environment and is not reducible to the latter. Indeed, subjective perception leads to the intellectual inner life of the individual...''p.418; ``experience only makes statements of the following type: an observer has made a certain (subjective) observation; and never any like this: a physical quantity has a certain value.'' p.420: In the final stage of his analysis he divides the world into parts I, II, and III, where part ``I was everything up to the retina of the observer, II was his retina, nerve tracts and brain, and III his abstract `ego' ''. Clearly, his ``abstract ego'' involves his consciousness. Von Neumann's formulation of quantum theory develops the dynamics of the interaction between these three parts. The evolution of the physical universe involves three related processes. The first is the deterministic evolution of the state of the physical universe. It is controlled by the Schroedinger equation of relativistic quantum field theory. This process is a local dynamical process, with all the causal connections arising solely from interactions between neighboring localized microscopic elements. However, this local process holds only during the intervals between quantum events. Each of these quantum events involves two other processes. The first is a choice of a Yes-No question by the mind-brain system. The second of these two processes is a choice by Nature of an answer, either Yes or No, to that question. This second choice is partially free: it is a random choice, subject to the statistical rules of quantum theory. The first choice is the analog in von Neumann theory of an essential process in Copenhagen quantum theory, namely the free choice made by the experimenter as to which aspect of nature is going to be probe. This choice of which aspect of nature is going to be probed, i.e., of which specific question is going to be put to nature, is an essential element of quantum theory: the quantum statistical rules cannot be applied until, and unless, some specific question is first selected. In Copenhagen quantum theory this choice is made by an experimenter, and this experimenter lies outside the system governed by the quantum rules. This feature of Copenhagen quantum theory is not altered in the transition to von Neumann quantum theory: the choice of which question will be put to nature, is not controlled by any rules that are known or understood within contempory physics. This choice associated a mind-brain-body system is, {\it in this specific sense}, a free choice: it is not governed by the physical laws of contemporary physics (i.e., quantum theory). This freedom constitutes a logical ``gap'' in the dynamical rules of contemporary physical theory. Only Yes-No questions are permitted: all other possibilities can be reduced to these. Thus each answer, Yes or No, injects one ``bit'' of information into the quantum universe. These bits of information are stored in the evolving objective quantum state of the universe, which is a compendium of these bits of information. But it evolves in accordance with the laws of atomic physics. Thus the quantum state has an ontological character that is in part matter like, since it is expressed in terms of the variables of atomic physics, and it evolves between events under the control of the laws of atomic physics. However, each event injects the information associated with a subjective perception by some observing system into the objective state of the universe. This conceptualization of natural process arises not from some preconceived speculative intuition, but directly from an examination of the mathematical structure injected into science by our study of the structure of the relationships between our experiences. The quantum state of the universe is thus rooted in atomic properties, yet is an informational structure that interacts with, and carries into the future, the informational content of each mental event. This state has causal efficacy because it controls, via statistical laws, the propensities for the occurrence of subsequent events. Once the physical world is understood in this way, as an objectively stored compendium of locally efficacious bits of information, the instantaneous transfers of information along the preferred surfaces ``now'' can be understood to be changes, not in just human knowledge, as in the Copenhagen interpretation, but in an absolute state of objective information. \\ \\ \noindent {\bf 10. MIND-BRAIN INTERACTION}\\ \noindent Von Neumann quantum theory is essentially a theory of the interaction between the evolving objective state of the physical universe and a sequence of mental events, each of which is associated with a localized individual system. The theory specifies the general form of the interaction between subjective knowings associated with individual physical systems and the physical states of those systems. The mathematical structure automatically ensures that when the state of the individual physical system associated with a mental event is brought into alignment with the content of that mental event the entire universe is simultaneously brought into alignment with that mental content. No special arrangement is needed to produce this key result: it is an unavoidable consequence of the quantum entanglements that are built into the mathematical structure. An essential feature of quantum brain dynamics is the strong action of the environment upon the brain. This action creates a powerful tendency for the brain to transform almost instantly [26] into an ensemble of components, each of which is very similar to an {\it entire classically-described brain}. I assume that this transformation does indeed occur, and exploit it in two important ways. First, this close connection to classical physics makes the dynamics easy to describe: classical language and imagery can be used to describe in familar terms how the brain behaves. Second, this description in familar classical terms makes it easy to identify the important ways in which the actual behaviour differs from what classical physics would predict. A key micro-property of the human brain pertains to the migration of calcium ions from the micro-channels through which these ions enter the interior of nerve terminals to the sites where they trigger the release the contents of a vesicle of neuro-transmitter. The quantum mechanical rules entail [27] that each release of the contents of a vesicle of neurotransmitter generates a quantum splitting of the brain into different classically describable components, or branches. Evolutionary considerations entail that the brain must keep the brain-body functioning in a coordinated way and, more specifically, must plan and effectuate, in any normally encountered situation, a single coherent course of action that meets the needs of that individual. But due to the quantum splitting mentioned above, the quantum brain will tend to decompose into components that specify alternative possible courses of action. Thus the purely mechanical evolution of the state of the brain in accordance with the Schroedinger equation will normally causes the brain to evolve into a growing ensemble of alternative branches, each of which is essentially {\it an entire classically described brain that specifies a possible plan of action.} This ensemble that constitutes the quantum brain is mathematically similar to an ensemble that occurs in a classical treatment when one takes into account the uncertainties in our knowledge of the intitial conditions of the particles and fields that constitute the classical representation of a brain. This close connection between what quantum theory gives and what classical physics gives is the basic reason why von Neumann quantum theory is able to produce all of the correct predictions of classical physics. To unearth specific differences caused by quantum effects one can start from this similarity at the lowest-order approximation, which yields the classical results, but then dig deeper. \\ \\ \noindent {\bf 11. THE PASSIVE AND ACTIVE ROLES OF MIND}\\ \noindent The founders of quantum theory recognized that the mathematical structure of quantum theory is naturally suited for, and seems to require, bringing into the dynamical equations two separate aspects of the interaction between the physical universe and the minds of the experimenter/observers. The first of these two aspects is the role of the experimenter in choosing what to attend to; which aspect of nature he wants to probe; which question he wants to ask about the physical world. This is the active role of mind. The second aspect is the recognition, or coming to know, the answer that nature returns. This is the passive role of mind.\\ \\ \noindent {\bf 12. THE PHYSICAL COUNTERPART OF THE PASSIVE PSYCHICAL EVENT}\\ \noindent I have mentioned the Schroedinger evolution of the state $S(t)$ of the universe. The second part of the orthodox quantum dynamics consists of an event that {\it discards} from the ensemble of quasi-classical elements mentioned above those elements that are incompatible with the answer that nature returns. This reduction of the prior ensemble of elements, which constitute the quantum mechanical representation of the brain, to the subensemble compatible with the ``outcome of the query'' is analogous to what happens in classical statistical mechanics when new information about the physical system is obtained. However, in the quantum case one must {\it in principle} regard the {\it entire ensemble of classically described brains} as real, because interference between the different elements are in principle possible. Each quantum event consists, then of a pair of events, one physical, the other psychical. The physical event reduces the initial ensemble that constitutes the brain prior to the event to the subensemble consisting of those branches that are compatible with the informational content of the associated psychical event. This dynamical connection means that, during an interval of conscious thinking, the brain changes by an alternation between two processes. The first is the generation, by a local deterministic mechanical rule, of an expanding profusion of alternative possible branches, with each branch corresponding to {\it an entire classically describable brain embodying some specific possible course of action.} The quantum brain is the {\it entire ensemble} of these separate, but equally real, quasi-classical branches. The second process involves an event that has both physical and psychical aspects. The physical aspect, or event, chops off all branches that are incompatible with the associated psychical aspect, or event. For example, if the psychical event is the experiencing of some feature of the physical world, then the associated physical event would be the updating of the brain's representation of that aspect of the physical world. This updating of the (quantum) brain is achieved by {\it discarding} from the ensemble of quasi-classical brain states all those branches in which the brain's representation of the physical world is incompatible with the information content of the psychical event. This connection is similar to a functionalist account of consciouness. But here it is expressed in terms of a dynamical interaction that is demanded by the requirement that the objective formulation of the theory yield the same predictions about connections between our conscious experiences that the empirically validated Copenhagen quantum theory gives. The interaction is the exact expression of the basic dynamical rule of quantum theory, which is the stipulation that each increment in knowledge is associated with a {\it reduction of the quantum state} to one that is compatible with the new knowledge. The quantum brain is an ensemble of quasi-classical components. As just noted, this structure is similar to something that occurs in classical statistical mechanics, namely a ``classical statistical ensemble.'' But a classical statistical ensemble, though structurally similar to a quantum brain, is fundamentally a different kind of thing. It is a representation of a set of truly distinct possibilities, only one of which is real. A classical statistical ensemble is used when a person does not know which of the conceivable possibilities is real, but can assign a `probability' to each possibility. In contrast, {\it all} of the elements of the ensemble that constitute a quantum brain are equally real: no choice has yet been made among them, Consequently, and this is the key point, entire ensemble acts as a whole in the determination of the upcoming mind-brain event. Each thought is associated with the actualization of some macroscopic quasi-stable features of the brain. Thus the reduction event is a macroscopic happening. Moreover, this event involves, dynamically, the entire ensemble of quasi-classical brain states. In the corresponding classical model each element of the ensemble evolves independently, in accordance with a micro-local law of motion that involves just that one branch alone. Thus there are basic dynamical differences between the quantum and classical models, and the consequences of these dynamical differences need to be studied in order to exhibit the quantum effects. The only freedom in the theory---insofar as we leave Nature's choices alone---is the choice made by the individual about {\it which} question it will ask next, and {\it when} it will ask it. These are the only inputs of mind to the dynamics of the brain. This severe restriction on the role of mind is what gives the theory its predictive power. Without this restriction mind could be free to do anything, and the theory would have no consequences. Asking a question about something is closely connected to focussing one's attention on it. Attending to something is the act of directing one's mental power to some task. This task might be to update one's representation of some feature of the surrounding world, or to plan or execute some other sort of mental or physical action. The key question is then: Can this freedom merely to choose which question is asked, and when it is asked, lead to any {\it statistical} influence of mind on the behaviour of the brain, where a `statistical' influence is a influence on values obtained by averaging over the properly weighted possibilities. The answer is Yes!\\ \\ \noindent {\bf 13. THE QUANTUM ZENO EFFECT}\\ \noindent There is an important and well studied effect in quantum theory that depends on the timings of the reduction events arising from the queries put to nature. It is called the Quantum Zeno Effect. It is not diminished by interaction with the environment [28]. The effect is simple. If the {\it same} question is put to nature sufficiently rapidly and the initial answer is Yes, then any noise-induced diffusion, or force-induced motion, of the system away from the subensemble where the answer is `Yes' will be suppressed: the system will tend to be confined to the subensemble where the answer is `Yes'. The effect is sometimes called the ``watched pot'' effect: according to the old adage ``A watched pot never boils''; just looking at it keeps it from changing. Also, a state can be pulled along in some direction by posing a rapid sequence of questions that change sufficiently slowly over time [29]. In short, according to the dynamical laws of quantum mechanics, the freedom to choose which questions are put to nature, and when they are asked, allows mind to influence the behaviour of the brain. A person is aware of almost none of the processing that is going on in his brain: unconscious brain action does almost everthing. So it would be both unrealistic and theoretically unfeasible to give mind unbridled freedom: the questions posed by mind ought to be determined in large measure by brain. What freedom is given to man? According to this theory, the freedom given to {\it Nature} is simply to provide a Yes or No answer to a question posed by a subsystem. It seems reasonable to restrict in a similar way the choice given to a human mind.\\ \\ \noindent {\bf 14. A SIMPLE DYNAMICAL MODEL}\\ \noindent It is easy to construct a simple dynamical model in which the brain does most of the work, in a local mechanical way, and the mind, simply by means of choices between `Yes' or `No' options, and control over the {\it rate} at which questions are put to nature, merely gives top-level guidance. Let $\{P\}$ be the set of projection operator that act only on the brain-body of the individual and that correspond to possible mental events of the individual. Let $P(t)$ be the $P$ in $\{P\}$ that maximizes $Tr P S(t)$, where $S(t)$ is the state of the universe at time $t$. This $P(t)$ represents the ``best possible'' question that could be asked by the individual at time $t$. Let the question associated with $P(t)$ be posed if $P(t)$ reaches a local maximum. If nature returns the answer `Yes' then the mental event associated with $P(t)$ occurs. Mental control comes in only through the option to rapidly pose this same question repeatedly, thus activating the Quantum Zeno Effect, which will tend to keep the state of the brain focussed on the plan of action specified by $P$. The Quantum Zeno Effect will not freeze up the brain completely. It merely keeps the state of the brain in the subspace where attention is focussed on pursuing the plan of action specified by $P$. In this model the brain does practically everything, but mind, by means of the limited effect of consenting to the rapid re-posing of the question already constructed and briefly presented by brain, can influence brain activity by causing this activity to stay focussed on the presented course of action.\\ \\ \noindent {\bf 15. AGREEMENT WITH CLAIMS OF WILLIAM JAMES}\\ \noindent Does this theory explain anything? Essentially this model was already in place [29, 30] when a colleague, Dr. Jeffrey Schwartz, brought to my attention some passages from ``Psychology: The Briefer Course'', written by William James [31]. In the final section of the chapter on Attention James writes: ``I have spoken as if our attention were wholly determined by neural conditions. I believe that the array of {\it things} we can attend to is so determined. No object can {\it catch} our attention except by the neural machinery. But the {\it amount} of the attention which an object receives after it has caught our attention is another question. It often takes effort to keep mind upon it. We feel that we can make more or less of the effort as we choose. If this feeling be not deceptive, if our effort be a spiritual force, and an indeterminate one, then of course it contributes coequally with the cerebral conditions to the result. Though it introduce no new idea, it will deepen and prolong the stay in consciousness of innumerable ideas which else would fade more quickly away. The delay thus gained might not be more than a second in duration--- but that second may be critical; for in the rising and falling considerations in the mind, where two associated systems of them are nearly in equilibrium it is often a matter of but a second more or less of attention at the outset, whether one system shall gain force to occupy the field and develop itself and exclude the other, or be excluded itself by the other. When developed it may make us act, and that act may seal our doom. When we come to the chapter on the Will we shall see that the whole drama of the voluntary life hinges on the attention, slightly more or slightly less, which rival motor ideas may receive. ...'' In the chapter on Will, in the section entitled ``Volitional effort is effort of attention'' James writes: ``Thus we find that {\it we reach the heart of our inquiry into volition when we ask by what process is it that the thought of any given action comes to prevail stably in the mind.}'' and later ``{\it The essential achievement of the will, in short, when it is most `voluntary,' is to attend to a difficult object and hold it fast before the mind. ... Effort of attention is thus the essential phenomenon of will.''} Still later, James says: {\it ``Consent to the idea's undivided presence, this is effort's sole achievement.''} ...``Everywhere, then, the function of effort is the same: to keep affirming and adopting the thought which, if left to itself, would slip away.'' This description of the effect of mind on the course of mind-brain process is remarkably in line with what had been proposed independently from purely theoretical consideration of the quantum physics of this process. The connections claimed by James are explained of the basis of the same dynamical principles that had been introduced by physicists explain atomic phenomena. Thus the whole range of science, from atomic physics to mind-brain dynamics, is brought together in a single rationally coherent theory of an evolving cosmos that consists of a physical reality that represents information, interacting via the laws of atomic physics with the closely related, but differently constituted, psychical aspects of nature.\\ \\ \noindent {\bf 16. AGREEMENT WITH RECENT WORK ON ATTENTION}\\ \noindent Much experimental work on attention and effort has occurred since the time of William James. That work has been hampered by the nonexistence of any putative physical theory that purports to explain how our conscious experiences influence activities in our brains. The behaviourist approach, which dominated psychological during the first half of the twentieth century, and which essentially abolished, in this field, not only the use of introspective data but also the very concept of consciousness, was surely motivated in part by the fact that consciousness had no natural place within the framework of classical physical theory. According to the principles of classical physical theory, consciousness makes no difference in behavior: all behavior is determined by microscopic causation without ever acknowledging the existence of consciousness. Thus philosophers who accepted the ideas of classical physics were driven to conclude that conscious experiences were either {\it identical} to corresponding classically describable activities of the brain, or were ``emergent'' properties. The first idea, the identity theory of mind, seems impossible to reconcile with the fact that according to the classical principles the brain is an assembly of local elements behaving in accordance with the local laws of classical physics, and that all higher-order dynamical properties are just re-expressions of the local causal links between the local elements, and are thus essentially statements about changing shapes and relative locations of various conglomerates of the elementary micro elements. But the existence of ``feelings'' and other conscious experiences is not just a re-expression of the causal links described by the principles of classical physical theory, or a necessary rational consequence of connections between various shapes and relative locations. And any ``emergent'' property that emerges from a system whose behavior is completely specified by the classical principles is only {\it trivially emergent}, in the same sense as is the {\it wheelness} often cited by Roger Sperry: ``wheelness'' did not exist in the physical world before wheels, and it exerts top-down causation, via the causal links specified by the classical principles. But the emergence of ``wheelness'' is not analogous to the emergence of ``consciousness'': the existence of the defining characteristics of the ``wheelness'' of a wheel follows rationally from a classical physics model of a wheel, but the existence of the defining experiential characteristics of the ``consciousness'' of a brain does not follow rationally from a classical physics model of the brain. The failure of the behaviourist programs led to the rehabilitation of ``attention'' during the early fifties, and many hundreds of experiments have been performed during the past fifty years for the purpose of investigating empirically those aspects of human behaviour that we ordinarily link to our consciousness. Harold Pashler's 1998 book ``The Psychology of Attention'' [32] describes a great deal of this empirical work, and also the intertwined theoretical efforts to understand the nature of an information-processing system that could account for the intricate details of the objective data. Two key concepts are the notions of a processing ``Capacity'' and of ``Attention''. The latter is associated with an internally directed {\it selection} between different possible allocations of the available processing ``Capacity''. A third concept is ''Effort'', which is linked to incentives, and to reports by subjects of ``trying harder''. Pashler organizes his discussion by separating perceptual processing from postperceptual processing. The former covers processing that, first of all, identifies such basic physical properties of stimuli as location, color, loudness, and pitch, and, secondly, identifies stimuli in terms of categories of meaning. The postperceptual process covers the tasks of producing motor actions and cognitive action beyond mere categorical identification. Pashler emphasizes [p. 33] that ``the empirical findings of attention studies specifically argue for a distinction between perceptual limitations and more central limitations involved in thought and the planning of action.'' The existence of these two different processes, with different characteristics, is a principal theme of Pashler's book [p. 33, 263, 293, 317, 404]. In the quantum theory of mind-brain being described here there are two separate processes. First, there is the unconscious mechanical brain process governed by the Schroedinger equation. As discussed in ref. 22, this brain processing involves dynamical units that are represented by complex patterns of neural activity (or, more generally, of brain activity) that are ``facilitated'' by use, and such that each unit tends to be activated as a whole by the activation of several of its parts: this explains the development of brain process through ''association''. The brain evolves mechanically by the dynamical interplay of these dynamic units, and by feed-back loops that strengthen or weaken appropriate input channels. Each individual quasi-classical element of the ensemble of alternative possible brain states that constitutes the quantum brain creates, on the basis of clues, or cues, coming from various sources, a plan for a possible coherent course of action. Quantum uncertainties entail that a host of different possibilities will emerge, and hence that the quantum brain will evolve into a set of component classically describable brains representing different possible courses of action. [See ref. 22.] This mechanical phase of the processing already involves some selectivity, because the various input clues contribute either more or less to the evolving brain process according to the degree to which these inputs activate, via associations, the patterns that survive and turn into the plan of action. This conception of brain dynamics seems to accommodate all of the perceptual aspects of the data described by Pashler. But it is the high-level processing, which is more closely linked to our active mentally controlled conscious thinking, that is of prime interest here. The data pertaining to this second process is the focus of part II of Pashler's book. Mental intervention has, according to the quantum-physics-based theory described here, several distinctive characteristics. It consists of a sequence of discrete events each of which consents to an integrated course of action presented by brain. The rapidity of these events can be increased with effort. Effort-induced speed-up of the rate of occurrence of these events can, by means of the quantum Zeno effect, keep attention focussed on a task. Between 100 and 300 msec of consent seem to be needed to fix a plan of action. Effort can, by increasing the number of events per second, increase the mental input into brain activity. Each conscious event picks out from the multitude of quasi-classical possibilities that comprise the quantum brain the subensemble that is compatible with the conscious experience. The correspondence between the mental event and the associated physical event is this: the physical event reduces the prior physical ensemble of alternative possibilities to the subensemble compatible with the mental event. This connection will be recognized as the core interpretive postulate of Copenhagen quantum theory: the physical event reduces the prior state of the observed system to the part of it that is compatible with the experience of the observer. Examination of Pashler's book shows that this quantum-physics-based theory accommodates naturally all of the complex structural features of the empirical data that he describes. He emphasizes [p. 33] a specific finding: strong empirical evidence for what he calls a central processing bottleneck associated with the attentive selection of a motor action. This kind of bottleneck is what the quantum-physics-based theory predicts: the bottleneck is precisely the single linear sequence of mind-brain quantum events that von Neumann-Wigner quantum theory is built upon. Pashler [p. 279] describes four empirical signatures for this kind of bottleneck, and describes the experimental confirmation of each of them. Much of part II of Pashler's book is a massing of evidence that supports the existence of a central process of this general kind. This bottleneck is not automatic within classical physics. A classical model could easily produce simultaneously two responses in different modalities, say vocal and manual, to two different stimuli arriving via two different modalities, say auditory and tactile: the two processes could proceed via dynamically independent routes. Pashler [p. 308] notes that the bottleneck is undiminished in split-brain patients performing two tasks that, at the level of input and output, seem to be confined to different hemispheres. Pashler states [p. 293] ``The conclusion that there is a central bottleneck in the selection of action should not be confused with the ... debate (about perceptual-level process) described in chapter 1. The finding that people seem unable to select two responses at the same time does not dispute the fact that they also have limitations in perceptual processing...''. I have already mentioned the independent selectivity injected into brain dynamics by the purely mechanical part of the quantum mind-brain process. The queuing effect for the mind-controlled motor responses does not exclude interference between brain processes that are similar to each other, and hence that use common brain mechanisms. Pashler [p. 297] notes this distinction, and says ``the principles governing queuing seem indifferent to neural overlap of any sort studied so far.'' He also cites evidence that suggests that the hypthetical timer of brain activity associated with the cerebellum ``is basically independent of the central response-selection bottleneck.''[p. 298] The important point here is that there is in principle, in the quantum model, an essential dynamical difference between the unconscious processing carried out by the Schroedinger evolution, which generates via a local process an expanding collection of classically conceivable possible courses of action, and the process associated with the sequence of conscious events that constitutes a stream of consciousness. The former are not limited by the queuing effect, because all of the possibilities develop in parallel, whereas the latter do form elements of a single queue. The experiments cited by Pashler all seem to support this clear prediction of the quantum approach. An interesting experiment mentioned by Pashler involves the simultaneous tasks of doing an IQ test and giving a foot response to a rapidly presented sequences of tones of either 2000 or 250 Hz. The subject's mental age, as measured by the IQ test, was reduced from adult to 8 years. [p. 299] This result supports the prediction of quantum theory that the bottleneck pertains to both `intelligent' behaviour, which requires conscious processing, and selection of motor response. Another interesting experiment showed that, when performing at maximum speed, with fixed accuracy, subjects produced responses at the same rate whether performing one task or two simultaneously: the limited capacity to produce responses can be divided between two simultaneously performed tasks. [p. 301] Pashler also notes [p. 348] that ``Recent results strengthen the case for central interference even further, concluding that memory retrieval is subject to the same discrete processing bottleneck that prevents simultaneous response selection in two speeded choice tasks.'' In the section on ``Mental Effort'' Pashler reports that ``incentives to perform especially well lead subjects to improve both speed and accuracy'', and that the motivation had ``greater effects on the more cognitively complex activity''. This is what would be expected if incentives lead to effort that produces increased rapidity of the events, each of which injects into the physical process, via quantum selection and reduction, bits of control information that reflect mental evaluation. Studies of sleep-deprived subjects suggest that in these cases ``effort works to counteract low arousal''. If arousal is essentially the rate of occurrence of conscious events then this result is what the quantum model would predict. Pashler notes that ``Performing two tasks at the same time, for example, almost invariably... produces poorer performance in a task and increases ratings in effortfulness.'' And ``Increasing the rate at which events occur in experimenter-paced tasks often increases effort ratings without affecting performance''. ``Increasing incentives often raises workload ratings and performance at the same time.'' All of these empirical connections are in line with the general principle that effort increases the rate of conscious events, each of which inputs a mental evaluation and a selection or focussing of a course of action, and that this resource can be divided between tasks. Additional supporting evidence comes from the studies of the effect of the conscious process upon the storage of information in short-term memory. According to the physics-based theory, the conscious process merely actualizes a course of action, which then develops automatically, with perhaps some occasional monitoring. Thus if one sets in place the activity of retaining in memory a certain sequence of stimuli, then this activity can persist undiminished while the central processor is engaged in another task. This is what the data indicate. Pashler remarks that ''These conclusions contradict the remarkably widespread assumption that short-term memory capacity can be equated with, or used as a measure of, central resources.''[p.341] In the theory outlined here short-term memory is stored in patterns of brain activity, whereas consciousness is associated with the selection of a subensemble of quasi-classical states. This distinction seems to account for the large amount of detailed data that bears on this question of the connection of short-term-memory to consciousness. [p.337-341] Deliberate storage in, or retrieval from, long-term memory requires focussed attention, and hence conscious effort. These processes should, according to the theory, use part of the limited processing capacity, and hence be detrimentally affected by a competing task that makes sufficient concurrent demands on the central resources. On the other hand, ``perceptual'' processing that involves conceptual categorization and identification without conscious awareness should not interfer with tasks that do consume central processing capacity. These expectations are what the evidence appears to confirm: ``the entirety of...front-end processing are modality specific and operate independent of the sort of single-channel central processing that limits retrieval and the control of action. This includes not only perceptual analysis but also storasge in STM (short term memory) and whatever may feed back to change the allocation of perceptual attention itself.'' [p. 353] Pashler describes a result dating from the nineteenth century: mental exertion reduces the amount of physical force that a person can apply. He notes that ``This puzzling phenomena remains unexplained.'' [p. 387]. However, it is an automatic consequence of the physics-based theory: creating physical force by muscle contraction requires an effort that opposes the physical tendencies generated by the Schroedinger equation. This opposing tendency is produced by the quantum Zeno effect, and is roughly proportional to the number of bits per second of central processing capacity that is devoted to the task. So if part of this processing capacity is directed to another task, then the applied force will diminish. Pashler speculates on the possibility of a neurophysiological explanation of the facts he describes, but notes that the parallel versus serial distinction between the two mechanisms leads, in the classical neurophysiological approach, to the questions of what makes these two mechanisms so different, and what the connection between them is. [p.354-6, 386-7] After analyzing various possible mechanisms that could cause the central bottleneck, Pashler [p.307-8] says ``the question of why this should be the case is quite puzzling.'' Thus the fact that this bottleneck, and its basic properties, follow automatically from the same laws that explain the complex empirical evidence in the fields of classical and quantum physics means that the theory has significant explanatory power. Of course, some similar sort of structure could presumably be worked into a classical model. But a general theory of all of nature that automatically explains a lot of empirical data in a particular field on the basis of the general principles is normally judged superior to a special theory that is rigged after the fact to explain these data. It needs to be emphasized that there is at present absolutely no empirical evidence that favors the classical model over the quantum model described above. The classical model would have to be implemented as a statistical theory, due to the uncertainties in the initial conditions, and that statistical model is to first order the same as the simple quantum model described above. The quantum model has the advantage that at least it {\it could} be valid, whereas the classical model must necessarily fail when quantum effects become important. So nothing is lost by switching to quantum theory, but a lot is gained. Psychology and psychiatry gain the possibility of reconciling with neuroscience the essential psychological concept of the ability of our minds to guide our actions. And psycho-physics gains a dynamical model for the interaction of mind and brain. Finally, philosophy of mind is freed from the need to reconcile the existence of the directly known psychical realities, such as the pains that occur in our streams of consciousness, and those streams themselves, with a theoretical conception of nature that has no natural place for them, and no causal role for them to play.\\ \\ \noindent {\bf 17. THE EVOLUTION OF MIND}\\ \noindent The psychical realities that I have focussed on in this paper are human streams of consciousness. Those are the only exemplars actually known to human beings, and the only ones suseptible to direct empirical study. However, although we human scientist play a special role in the creation of our theories, we surely, according to the scientific perspective, play no such special role in natural process itself. The ideas of evolutionary theory mandate that the character of the psychical realities associated with those physical systems that possess such realities should develop in step with the pertinent physical properties of those systems, with the efficacy of the psychical realities providing the feed-back that drives the development of increasingly efficacious and beneficial forms. While I shall not enter at this time into the evolutionary problem, I note that it requires that systems that evolve by exploiting the causal efficacy of psychical realities associated with them must have some memory capacity, and that the most rudimentary sort of efficacious dynamical memory probably resides in sustained oscillatory motions. This suggests to me that the physical correlates of the psychical realities will reside in the low frequency components of the coulomb part of the electromagnetic field. These are dominated by the so-called ``coherent states'', which are known to be essentially classical in nature, and particulary robust. This is discussed in a little more detail in reference 29. This would allow psychical realities, in the sense considered here, to be present in the simplest life forms, and to predate life.\\ \noindent {\bf ACKNOWLEDGEMENT}\\ This paper has benefitted from constructive suggestions by Abner Shimony.\\ \\ \noindent {\bf REFERENCES}\\ \noindent 1. {\it Physics Today}, ``Nonlocality gets more real,'' December 1998, p. 9.\\ \noindent 2. W. Tittle, J. Brendel, H. Zbinden, and N. Gisin,\\ ``Violation of Bell inequalities by photons more than 10km apart,''\\ {\it Phys. Rev. Lett.} {\bf 81}, 3563 (1998).\\ \noindent 3. W. Tittle, J. Brendel, H. Zbinden, and N. Gisin, ``Long-distance Bell-type tests using energy-time entangled photons,'' {\it Phys. Rev.} {\bf A59}, 4150 (1999).\\ \noindent 4. N. Bohr, ``Can quantum-mechanical description of physical reality \\ be considered complete?'' {\it Phys. Rev.} {\bf 48}, 696 (1935).\\ \noindent 5. P.A.M. Dirac, at 1927 Solvay Conference {\it Electrons et photons:\\ Rapports et Discussions du cinquieme Conseil de Physique}\\ (Gauthier-Villars, Paris, 1928).\\ \noindent 6. W. Heisenberg, ``The representation of nature in contemporary physics,'' {\it Daedalus} {\bf 87}, 95-108 (1958).\\ \noindent 7. A. Einstein, B. Podolsky, and N. Rosen, ``Can quantum-mechanical\\ description of physical reality be considered complete?''\\ {\it Phys. Rev. {\bf 47}, 777 (1935).\\ \noindent 8. N. Bohr, ``Can quantum-mechanical description of physical reality\\ be considered complete?'' } {\it Phys. Rev.} {\bf 48}, 696 (1935).\\ \noindent 9. A. Einstein, in {\it Albert Einstein: Philosopher-Physicist}, P. A. Schilpp, ed.\\ (Tudor, New York, 1951) p.669.\\ \noindent 10. M. Gell-Mann, in {\it The Nature of the Physical Universe:\\ the 1976 Nobel Conference}, (Wiley, New York, 1979) p. 29. \\ \noindent 11. J. von Neumann, {\it Mathematical Foundations of Quantum Mechanics}\\ (Princeton University Press, Princeton, NJ, 1955)\\ Translation from the 1932 German original.\\ \noindent 12. N. Bohr, {\it Atomic Physics and Human Knowledge}\\ (Wiley, New York, 1958) p.88, \& p.72.\\ \noindent 13. W. Pauli, See quotations in Ch. 7 of ref. 25\\ \noindent 14. For a further development of von Neumann's ideas see:\\ F. London and E. Bauer, {\it La theorie de l'observation en mechanique\\ quantique} (Hermann \& Cie, Paris, 1939)\\ (Translated into English and included in the anthology of Wheeler and Zurek).\\ \noindent 15. Eugene Wigner, ``Remarks on the mind-body problem,'' {\it Symmetries and Reflections} (Indiana Univ. Press, Bloomington, 1967) Ch. 13.\\ \noindent 16. S. Tomonaga, ``On a relativistically invariant formulation of the quantum theory of wave fields,'' {\it Progress of Theoretical Physics} {\bf 1}, 27 (1946).\\ \noindent 17. J. Schwinger, ``The theory of quantized fields, I,'' {\it Phys. Rev.} {\bf 82}, 914 (1951).\\ \noindent 18. G.F. Smoot et. al., ``Structure in the COBE differential microwave radiometer first-year maps,'' {\it Astrophysical Journal} {\bf 396}, L1 (1992).\\ \noindent 19. J.S. Bell, ``On the Einstein Podolsky Rosen Paradox,'' {\it Physics} {\bf 1}, 195 (1964); and in {\it Speakable and Unspeakable in Quantum Mechanics}\\ (Cambridge Univ. Press, 1987) Ch. 4;\\ J. Clauser and A. Shimony, {\it Rep. Prog. Phys.} {\bf 41}, 1881 (1978);\\ A. Shimony, ``Contextual Hidden Variable Theories'' in\\ {\it Br. J. for the Phil. Sci.} {\bf 35}, 25 (1984), and in his\\ {\it Search for a Naturalistic World View II}, (Cambridge U. Press, 1993).\\ \noindent 20. H. Stapp, ``Non local character of quantum theory,'' {\it Epistemological Letters}, June 1978. (Assoc. F Gonseth, Case Postal 1081, Bienne Switzerland).\\ (Colloquium on Bell's Theorem: March 3-4, 1978).\\ \noindent 21. A Fine, ``Hidden-variables, joint probabilities, and the Bell Inequalities, {\it Phys. Rev. Lett.} {\bf 48}, 291 (1982).\\ \noindent 22. N. Bohr, {\it Atomic Physics and Human Knowledge}\\ (Wiley, New York, 1958) p.72.\\ \noindent 23. L. Hardy, ``Nonlocality for two particles without inequalities for\\ almost all entangled states,'' {\it Phys. Rev. Lett.} {\bf 71}, 1665 (1993):\\ A. White, D. F. V. James, P. Eberhard, and P.G. Kwiat, ``Nonmaximally\\ entangled states: production, characterization, and utilization,''\\ {\it Phys. Rev. Lett.}, {\bf 83}, 3103 (1999).\\ \noindent 24. A. Shimony and H. Stein, ``On Stapp's `Nonlocal Character of Quantum Theory' ,'' {\it Amer. J. Phys.} To appear.\\ \noindent 25. H. Stapp, ``Reply to ``On Stapp's `Nonlocal Character of Quantum\\ Theory' '', '' {\it Amer. J. Phys.} To appear.\\ \noindent 26. M. Tegmark, ``The importance of quantum decoherence\\ in brain process,'' {\it Phys. Rev. E} {\bf 61}, 4194-4206 (2000).\\ \noindent 27. H. Stapp, {\it Mind, Matter, and Quantum Mechanics}\\ (Springer-Verlag, New York, Berlin. 1993) p.152 \& Ch VI.\\ \noindent 28. H. Stapp, ``The Importance of Quantum Decoherence in Brain process,''\\ Lawrence Berkeley National Laboratory Report LBNL-46871.\\ (quant-ph/0010029)\\ \noindent 29. H. Stapp, ``Whiteheadian Process and Quantum Theory of Mind,''\\ Lawrence Berkeley National Laboratory Report LBNL-42143\\ (http://www-physics.lbl.gov/$\sim$stapp/stappfiles.html).\\ \noindent 30. H. Stapp, ``Attention, Intention, and Will in Quantum Physics,'',\\ {\it Journal of Consciousness Studies} {\bf 6}, 143 (1999). (quant-ph/9905054).\\ \noindent 31. Wm. James, {\it Psychology: The Briefer Course}, Gordon Allport, ed.\\ (University of Notre Dame Press, Notre Dame, IN) Ch. 4 \& Ch. 17.\\ \noindent 32. Harold Pashler, {\it The Psychology of Attention},\\ (MIT Press, Cambridge MA, 1998). \end{document}