Read The Dancing Wu Li Masters Online
Authors: Gary Zukav
The Dancing Wu Li Masters (42 page)
In 1982, Alain Aspect, a physicist at the Institute of Optics, University of Paris, in Orsay, France, conducted an experiment which was similar to the Clauser-Freedman experiment, but with one important difference: the settings on the measuring devices in Aspect’s experiment could be changed at the last minute (or, more precisely, at the last microsecond).
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Changing the settings on the measuring devices at the last minute insures that information about the setting of the measuring device in either area does not have sufficient time, traveling at the speed of light or less, to reach the other region before the particle arrives.
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In other words, Aspect, in effect, performed Bohm’s thought experiment.
Like the Clauser-Freedman experiment (and several Clauser-Freedman-type experiments which had been performed in the meanwhile),
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Aspect’s experiment verified the statistical predictions of quantum mechanics. Because Aspect’s experiment, however, satisfied the conditions upon which the logical analysis leading to the phenom
enon of superluminal transfer of information is based (that area A and area B are space-like separated) physicists were able to deduce this phenomenon solely on the basis of Aspect’s experimental results. This lent considerable credence to the conclusion which Stapp had reached five years previously. Wrote Stapp:
Quantum phenomena provide
prima facie
evidence that information gets around in ways that do not conform to classical ideas. Thus, the idea that information is transferred superluminally is,
a priori
, not unreasonable.
Everything we know about Nature is in accord with the idea that the fundamental process of Nature lies outside space-time…but generates events that can be located in space-time. The theorem of this paper supports this view of Nature by showing that superluminal transfer of information is necessary, barring certain alternatives…that seem less reasonable. Indeed, the reasonable philosophical position of Bohr seems to lead to the rejection of the other possibilities, and hence, by inference, to the conclusion that superluminal transfer of information is necessary.
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Thus, eighty-two years after Planck presented his quantum hypothesis, physicists have been forced to consider the possibility, among others, that the superluminal transfer of information between space-like separated events may be an integral aspect of our physical reality.
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,
†
Bell’s theorem showed that either the statistical predictions of quantum theory or the principle of local causes is false. It did not say which one is false, but only that both of them cannot be true. When Clauser and Freedman confirmed that the statistical predictions of quantum theory are correct, the startling conclusion was inescapable: The principle of local causes must be false! However, if the principle of local causes fails and, hence, the world is not the way it appears to be, then what is the true nature of our world?
There are several mutually exclusive possibilities. The first possibility, which we have just discussed, is that, appearances to the contrary, there really may be no such thing as “separate parts” in our world (in the dialect of physics, “locality fails”). In that case, the idea that events are autonomous happenings is an illusion. This would be the case for any “separate parts” that have interacted with each other at any time in the past. When “separate parts” interact with each other, they (their wave functions) become correlated (through the exchange of conventional signals) (forces). Unless this correlation is disrupted by other external forces, the wave functions representing these “separate parts” remain correlated forever.
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For such correlated “separate parts,” what an experimenter does in this area has an intrinsic effect upon the results of an experiment in a distant, space-like separated area. This possibility entails a faster-than-light communication of a type different than conventional physics can explain.
In this picture, what happens here is intimately and immediately connected to what happens elsewhere in the universe, which, in turn, is intimately and immediately connected to what happens elsewhere in the universe, and so on, simply because the “separate parts” of the universe are not separate parts.
“Parts,” wrote David Bohm:
are seen to be in immediate connection, in which their dynamical relationships depend, in an irreducible way, on the state of the whole system (and, indeed, on that of broader systems in
which they are contained, extending ultimately and in principle to the entire universe). Thus, one is led to a new notion of
unbroken wholeness
which denies the classical idea of analyzability of the world into separately and independently existent parts…
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According to quantum mechanics, individual events are determined by pure chance. We can calculate, for example, that a certain percentage of spontaneous positive kaon decays will produce an antimuon and a neutrino (63%), a certain percentage will produce a positive pion and a neutral pion (21%), a certain percentage will produce two positive pions and a negative pion (5.5%), a certain percentage will produce a positron, a neutrino, and a neutral pion (4.8%), a certain percentage will produce an antimuon, a neutrino, and a neutral pion (3.4%), and so on. However, quantum theory cannot predict
which
decay will produce which result. Individual events, according to quantum mechanics, are completely random.
Said another way, the wave function which describes spontaneous kaon decays contains all of these possible results. When the decay actually happens, one of these potentialities is converted into an actuality. Even though the probability of each potentiality can be calculated, which potentiality actually happens at the moment of decay is a matter of chance.
Bell’s theorem implies that which decay reaction occurs at a certain time is
not
a matter of chance. Like everything else, it is dependent upon something which is happening elsewhere.
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In the words of Stapp:
…the conversion of potentialities into actualities cannot proceed on the basis of locally available information. If one accepts the usual ideas about how information propagates through space and time, then Bell’s theorem shows that the macroscopic responses cannot be independent of far-away causes. This problem is neither resolved nor alleviated by saying that the response is determined by “pure chance.” Bell’s theorem proves precisely that the determination of the macroscopic response must be “nonchance,” at least to the extent of allowing some sort of dependence of this response upon the far-away cause.
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Superluminal quantum connectedness seems to be, on the surface at least, a possible explanation for some types of psychic phenomena. Telepathy, for example, often appears to happen instantaneously, if not faster. Psychic phenomena have been held in disdain by physicists since the days of Newton. In fact, most physicists do not even believe that they exist.
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In this sense, Bell’s theorem could be the Trojan horse in the physicists’ camp; first, because it proves that quantum theory requires connections that appear to resemble telepathic communication, and second, because it provides the mathematical framework through which serious physicists (all physicists are serious) could find themselves discussing types of phenomena which, ironically, they do not believe exist.
The failure of the principle of local causes does not necessarily
mean that superluminal connections actually exist. There are other ways to explain the failure of the principle of local causes. For example, the principle of local causes—that what happens in one area does not depend upon variables subject to the control of an experimenter in a distant space-like separated area—is based upon two tacit assumptions which are so obvious that they are easy to overlook.
First, the principle of local causes assumes that we have a choice about how we perform our experiments. Imagine that we are doing Clauser and Freedman’s photon experiment. We have before us a switch which determines how the polarizers will be positioned. If we throw the switch up, the polarizers are aligned with each other. If we throw the switch down, the polarizers are oriented at right angles with each other. Suppose that we decide to throw the switch up and align the polarizers. Normally, we assume that
we could have
thrown the switch down and oriented the polarizers at right angles if we had wanted to. In other words, we assume that we are free to decide whether the switch before us will be up or down when the experiment begins.
The principle of local causes assumes (“…variables subject to the control of an experimenter…”) that we possess and can exercise a free will in the determination of how to perform our experiment. Second, and this is even easier to overlook, the principle of local causes assumes that if we had performed our experiment in a different way than we actually did perform it, we would have obtained some definite results. These two assumptions—that we can choose how to perform our experiment and that each of our choices, including those that we did not select, produces or would have produced definite results—is what Stapp calls “contrafactual definiteness.”
The fact, in this case, is that we decided to perform our experiment with the switch in the “up” position. We assume that, contrary to this fact (contrafactually), we
could have
performed it with the switch in the “down” position. By performing the experiment with the switch in the “up” position, we obtained some definite results (a certain number of clicks in each area). Therefore, we assume that if we had chosen to perform the experiment with the switch in the “down”
position, we likewise would have obtained some definite results. (It is not necessary that we be able to calculate what these other results are.) Odd as it may seem, some physical theories, as we shall see, do not assume that “what would have happened if…” produces definite results.
Since Bell’s theorem shows that, assuming the validity of quantum theory, the principle of local causes is incorrect, and, if we do not want to accept the existence of superluminal connections (“the failure of locality”) as the reason for the failure of the principle of local causes, then we are forced to confront the possibility that our assumptions about contrafactual definiteness are incorrect (“contrafactual definiteness fails”). Since contrafactual definiteness has two parts, there are two ways in which contrafactual definiteness could fail.
The first possibility is that free will is an illusion (“contrafactualness fails”). Perhaps there is no such thing as “what would have happened if….” Perhaps there can be only what is. In this case, we are led to a
superdeterminism
. This is a determinism far beyond ordinary determinism. Ordinary determinism states that once the initial situation of a system is established, the future of the system also is established since it must develop according to inexplorable laws of cause and effect. This type of determinism was the basis of the Great Machine view of the universe. According to this view, however, if the initial situation of a system, like the universe, is changed, then the future of the system also is changed.
According to superdeterminism,
not even the initial situation of the universe could be changed
. Not only is it impossible for things to be other than they are, it is even impossible that the initial situation of the universe could have been other than what it was. No matter what we are doing at any given moment, it is the only thing that
ever
was possible for us to be doing at that moment.
Contrafactual definiteness also fails if the “definiteness” assumption in it fails. In this case, we do have a choice in the way that we perform our experiments, but “what would have happened if…” does not produce any definite results. This alternative is just as strange as it sounds. It is also just what comes out of the Many Worlds Inter
pretation of Quantum Mechanics. According to the Many Worlds theory, whenever a choice is made in the universe between one possible event and another, the universe splits into different branches.
In our hypothetical experiment we decided to throw the switch into the “up” position. When the experiment was performed with the switch in the “up” position, it gave us a definite result (a certain number of clicks in each area). However, according to the Many Worlds theory, at the moment that we threw the switch up, the universe split into two branches. In one branch, the experiment was performed with the switch in the “up” position. In the other branch, the experiment was performed with the switch in the “down” position.
Who performed the experiment in the second branch? There is a different edition of
us
in each of the different branches of the universe! Each edition of us is convinced that
our
branch of the universe is the entirety of reality.
The experiment in the second branch, the experiment which was performed with the switch in the “down” position, also produced a definite result (a certain number of clicks in each area). However, that result is in another branch of the universe, not in ours. Therefore, as far as we in this branch of the universe are concerned, “what would have happened if…” actually
did
happen, and actually did produce definite results, but in a branch of the universe which is forever beyond our experiential reality.
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On the next page is a diagram of the logical implications of Bell’s
theorem. It is drawn from informal discussions of the Fundamental Physics Group at the Lawrence Berkeley Laboratory, under the direction and sponsorship of Dr. Elizabeth Rauscher. These discussions, in turn, were based primarily upon the work of Henry Stapp.
