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Coda: on the Meaning of Nonlocality

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Coda: on the Meaning of Nonlocality Coda: On the Meaning of Nonlocality All things by immortal power, Near or far, Hiddenly, To each other linked are That thou canst not stir a flower Without troubling of a star. Francis Thompson Apparently, quantum theory postulates the existence of correlations very similar to the ones implied by the words of the poet. Nonlocal entanglement as well as other long-range quantum correlations seem to have no limits in that they hold independently of the distance between their component "parts." Thus, if one does not for practical purposes simply ignore EPR­ type correlations, there are no separable "objects": according to quantum mechanics, an atom on the tip of your finger is literally linked with the faintest stars, right now. But is this really so? Actually, of course, we do not know. In fact, such claims are only extrapolations from our present-day experience, including the corresponding theoretical framework. However, the approach of quan­ tum cybernetics presented here has already indicated one possible limita­ tion of nonlocal effects in that it takes a finite time for changes to be me­ diated along nonlocal distances. Moreover, it is certainly conceivable that in a model beyond today's quantum theory there exists a "noise term" to 136 Coda: On the Meaning of Nonlocality be added to nonlocal correlations. Consequently, with increasing distance between, say, two "parts" of an entangled system, the noise would add up, so that eventually the correlations would break down. Today, the range of nonlocal correlations is proven by experiment up to distances of several kilometers, so one can think of experiments over interplanetary distances, for example, to inquire whether entanglement persists or is faded out due to some "subquantum noise." However, other possible mechanisms are known in present-day theories to produce fairly isolated objects. Both in high-energy - as well as in solid-state - physics, one speaks of so-called "dressed particles" when the "naked particles" of the ordinary theory strongly interact with their en­ vironment. Such is the case with collisions of particles at high energies, or with particles strongly bound to the potentials of a solid-state body. Thereby, parts of the environmental effects are added to the newly created object so that it becomes a "dressed particle." In general, it seems that, despite entanglement and EPR correlations, evolution has found ways to break down a holistic symmetry by "self-organizing" objects into organiza­ tionally autonomous units. Consequently, one arrives at a characterization of evolution that is somehow opposite to the usual assertion that more and more complex forms of organization arise. However, considering that the word "complex" is derived from the Latin "complector," that is, to put together, we see that a single electron is more "put together" (i.e., more complex) than a dressed particle in a solid-state body: an electron is EPR correlated to the environment of its radiation field with infinitely many de­ grees of freedom, whereas a dressed particle's degrees of freedom are much more reduced by the particle's "confinement" in the solid state. Therefore, the more "complicated" (from the Latin "com-plicare," i.e., folding together) an object is (as opposed to "simple" or unrestricted with regard to EPR correlations), the fewer degrees of freedom of interaction with the environment there are, that is, the less "complex" such an ob­ ject is. Thus, it is more appropriate to describe evolutionary processes in terms of the emergence and development of autonomous units with ever fewer EPR correlations: viewed quantum-mechanically, then, evolution is a process of de-complexification into states of ever higher forms of autonomy [Grossing 1993a]. To obtain a deeper understanding of the implications of quantum cyber­ netics, it is essential to re-introduce modes of thinking based on continuum models for some "medium," i.e., to explicitly renounce an "atomistic" strat­ egy. In this regard, the approach of quantum cybernetics is just one in a series of slightly differing attempts to provide a causal description of quan­ tum processes, their common underlying assumption being the existence of some subquantum medium. One can only speculate what this medium consists of, but there may well be further "smallest units" constituting it. What we today call "elementary particles" may therefore some day appear as nonlinear modifications of an apparently continuous medium that only Coda: On the Meaning of Nonlocality 137 upon further resolution would decompose into the "atoms" of the aether. Thus, there may arise a new kind of atomism in the 21 st century, with the atoms then being the "discrete" elements of the "continuous" sub-quantum medium. Again, one would be entitled to say with Democritus of Abdera that " ... in truth there only exist atoms and the void." However, we might also realize that thereby we would only spin the wheel of controversies be­ tween adherents of the discrete versus adherents of the continuous by one more turn, thus fulfilling another cycle in the dynamic process of "scientific cognition" that spirals along the axis of time. One particularly intriguing implication of quantum theory is, as we have seen, that "objects" in the common sense of the word cannot exist, or rather: whenever we define our "object," it must be clear that we also co­ define a context in which the meaning of the "object" is operational, but which also excludes other meanings. In particular, "objects" can only be defined if certain EPR-type correlations are ignored. However, what about "subjects," then? Would not the same type of definitory restrictions have to hold for "subjects" as we1l3? In fact, as causal approaches to quantum theory are "objective" theories excluding the observer, said "objectivity" is subject to the same type of limitations: choosing a particular scientific approach is a "subjective" (or better "inter-subjective") decision which is, of course, also context-dependent.4 Thus, it is also interesting to explore other possible contexts, like, for example: what are the consequences that we as "subjects" consist of quan­ tum systems with their characteristic nonlocal features? Furthermore, it is no more justified to describe subjects at the most basic physical level as a mere collection of atoms. Rather, the emerging new picture of space­ time and matter as manifestations of a "medium" entail that also we are modulations of the aether. What are the consequences of such a viewpoint? Naturally, such questions touch upon a whole gamut of different topics and thus are definitely beyond the scope of quantum theory per se, but they are nevertheless legitimate ones in the pursuit of curiosity driven research. Moreover, in reaching beyond the borders of conventional dis­ ciplinary boundaries, they may develop into whole new fields of research which today we can only vaguely circumscribe as "transdisciplinary" ones. Even within the domain of physics, the relations between issues on the quantum and on other (classical) levels can be seen in a new light, once 31 have written two books in German on these issues, centering around a proposed polar relationship between "subjectuals" and "objectuals," rather than subject-object duality: in [Grossing 1993b], 1 concentrate on "objectlike" ("ob­ jectual") determinants of theory building in physics, whereas in [Grossing 1997], 1 discuss "subjectlike" ("subjectual") organizations of knowledge, with physics being one of them. 4However, this does not make the approaches arbitrary or dependent on one's taste only - as with an artistic style, for example. 138 Coda: On the Meaning of Nonlocality systemic approaches are considered. For example, H. C. von Baeyer has reported on the discovery by Randall Hulet of a previously unexpected mirroring of microphysics in macrophysics in the behavior of Bose-Einstein condensates. For gases in which the interatomic force is attractive, it had recently turned out that Bose-Einstein condensates can be achieved only in well defined small accumulations of matter: if the condensed cloud in­ cludes more than about 1,000 atoms, it becomes too large and collapses into a liquid. In other words, the attractive force and the gas pressure then cease to balance each other. Now, von Baeyer notes that all stars are ac­ cumulations of particles in equilibrium between competing attractive and repulsive forces, where the equilibrium persists only for fixed, well-known ranges in the number of constituents: "In this light it is exciting to see similar limitations arising in the realm of the very small. Hulet, for exam­ ple, compares the collapse of his little lithium clouds to 'what happens in a supernova,' when gravity finally overcomes the outward pressure of the stellar plasma and the star falls in on itself. The image provides a wonder­ fullink between quantum theory and astrophysics." Von Baeyer concludes with the interesting conjecture that ''the replication of behavior is more momentous than the mere replication of form" [von Baeyer]. It is well known that similarities of form in different areas of the natural world, though very suggestive at first sight, do not imply any deeper con­ nection at the physical level. 5 However, when it comes to comparing similar­ ities in the dynamical behavior of different systems, one still may carefully enquire whether or not there does exist a more abstract common ground. To give another example, I just remind the reader of the familiar didactic practice to illustrate the self-interference of a quantum at a double-slit by a corresponding interference pattern produced by water waves. To the extent that one can ignore the particlelike aspects of quantum systems, the dy­ namics of water waves around a double slit is even mathematically identical to the corresponding dynamics of light, for example. In this way, Huygens' principle provides the common ground for both phenomena - a fact, which in a rudimentary form was already known to Leonardo da Vinci.
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