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2 - Experiments in Physics and Some Models
The cat's condition is described in great detail by some authors. They insist that the cat's life does not exist unconditionally. Davies [2.2] writes of the cat:
Heisenberg suggested a third possibility in which it is neither true nor false that the cat is alive. He writes [2.5]:
"Let us consider an atom moving in a closed box which is divided by a wall into two equal parts. The wall may have a very small hole so that the atom can go through. Then the atom can, according to classical logic, be either in the left half of the box or in the right half. There is no third possibility: "tertium non datur". In quantum theory, however, we have to admit - if we use the word "atom" and "box" at all - that there is other possibilities which are in a strange way mixtures of the two former possibilities. This is necessary for explaining the results of our experiments."
"According to Wigner's theory before there was intelligent life, the universe did not really exist."
"Ask Wigner's friend what he felt during the period before the box was opened. There is no doubt that he would answer "nothing", in spite of the fact that his body was supposed to have been in a live-dead state."
"Now, of course, this whimsical example can't be taken too seriously; [...] the "mixed state" describes our state of knowledge of the cat, not the state of the cat itself."
"The usual way is to say nothing about the actual experimental situation. In the tranquilizing philosophy of the schools - to use Einstein's lovely phrase - we are simply told, Don't ask!"
2-3 Causality in
There is a fundamental problem in the Berkeley-Copenhagen interpretation of Schrödinger's cat experiment because unconsciously, we need to find a real cause for the death of the cat. That cause must be related to the moment when the g rays are emitted. It cannot be due to the opening of the box and the observation by the observer. The real cause of a physical event can be studied by means of another gedanken experiment. Take the example of an atom in an excited state with a half life of 1 ms. Just after the excitation, a digital timer starts to count the number of nanoseconds spent before a photon is detected. The experiment is repeated many times. It is seen that, on average, it takes 1000 nanoseconds before a photon is detected. The mathematics of quantum mechanics can calculate such a result very accurately from the wave-function of the atom. We conclude that the half-life of the atom as being 1 micro second is a consequence of the particular wave-function involved.
Let us go back to our apparatus. After the first atom is excited, let us suppose that we have waited 930 nanoseconds before the photon is emitted. Why has that particular atom taken 930 nanoseconds instead of 800 or 1026 nanoseconds or any other value? Quantum mechanics cannot predict the exact time of each event. What phenomenon has determined that it happened at the particular value of 930 nanoseconds in that particular case? QM gives no explanation. That number is actually measured but QM claims that there is no cause for that particular observation.
In order to avoid the shame of no answer and avoid any possible further questions from curious minds, the excuse usually given is that
2-4 Dualistic Model.
One of the best illustrations of all the difficulties in the Berkeley-Copenhagen interpretation is found when we try to find a rational explanation for the behavior of light.
To explain the behavior of light, it has been assumed that something, emitted by the light source, is later detected by the detector. That thing is usually considered to be an electromagnetic wave packet or a particle called a photon. Since the exact nature of the thing that is transmitted has led to one of the most important paradoxes in science, we intentionally use the vague word thing, trying, unsuccessfully as everybody, to avoid preconceived ideas about the exact nature of the energy transmitted. However, we see that even the word thingis still not sufficiently vague because it implies an object or a wave packet.
It is usually considered that the emitted thing is either:
(a) a pure electromagnetic wave packet.
(b) a point particle.
(c) a blend of waves and particles in a fixed proportion.
(d) simultaneously a wave and a particle.
(e) one single thing changing unexpectedly from the aspect of a wave to the aspect of a particle.
Let us consider these five models and show that, whatever the model considered, they are all incompatible with realism. None of these five descriptions is compatible with physical reality. We will consider a rational alternative later in chapters 6 and 7.
(a) The hypothesis of pure E-M radiation is contradicted by observation. One example suffices to prove it. When a wave propagates according to Maxwell's theory, we know that it spreads in all directions. This is incompatible with the fact that, experimentally, all the energy (one photon) emitted by one single excited atom can be detected far away, (sometimes millions of light-years away) on a very small surface (on one single atom). If a spherical E-M wave were emitted around an emitting atom, it would be impossible to explain how one can detect all that energy concentrated on one single point at a great distance, as observed experimentally.
(b) The hypothesis that those things are nothing but point particles is easily rejected. On the one hand, we know that these things are easily diffracted by gratings or through multiple apertures. On the other hand, the fundamental properties of any particle are such that real point particles cannot, in principle, be diffracted by a grating or by passing through a multiple aperture. It is simple logic. Since diffraction patterns are actually observed experimentally, this cannot logically result from a particle. Consequently, the description of light as particles is unacceptable. It is contradicted by experiments.
(c) The hypothesis that these things are a blend of waves and particles is also unacceptable for at least two reasons:
i) If those things were a blend of waves and particles, we would then detect the wave component with a wave detector and the particle component with a particle detector. This means that the wave detector could detect only a part of the total energy, while the particle detector would detect the other part. This is not acceptable, because experimentally, the particle detector as well as the wave detector are able to detect the total energy.
ii) A second reason is the following. If part of the energy existed in the form of a particle, that part could not be diffracted by the grating located between the source and the detector, (since diffraction is a property belonging to waves). So, part of the signal would not be diffracted. This is contrary to observations.
(d) The hypothesis that those things are simultaneously a wave and a particle, as is frequently assumed, is equally contradictory. This can be realized from the fundamental meaning of waves and particles. On the one hand, we have seen that the fundamental characteristic of a wave is to expand and occupy a larger and larger volume in space. On the other hand, the fundamental characteristic of a particle is that the volume stays small during its motion. Consequently, if the thing is simultaneously a wave and a particle, this means that, after a while, the thing must occupy simultaneously a large volume (as a wave) and a small volume (as a particle). Such a description is clearly contradictory, since an object cannot be large and small at the same time.
(e) It is incompatible with realism that the solution is a description in which a particle and a wave unexpectedly change into one another. This impossibility can be deduced from the argument presented in
(d), since this would require that a large volume be compatible simultaneously with a small volume. In electromagnetic theory, there is no way a wave could contract in size. However, a contraction would then be necessary to form a particle at a later time, because at the moment of transformation of the wave into a particle, they must have the same size, at least momentarily. Since inverse expansion is not a characteristic of any wave, the incompatibility in size of a particle and wave makes that mechanism impossible.
One must conclude that none of the five hypotheses described above is compatible with causality and rationality. There is a sixth model that has not yet been considered. It will be considered in chap. 6 and 7. A correct description of the physical implications of Einstein's theory of relativity will be shown to give a solution that is naturally compatible with rationality and realism.
2.1 Cramer, John G., "The Transactional Interpretation of Quantum Mechanics", in Reviews of Modern Physics, Vol. 58, No. 3, 1986, p. 673.
2.2 Davies, Paul, Other Worlds: A Portrait of Nature in Rebellion Space, Superspace and the Quantum Universe, New York, Simon and Schuster, 1980, p. 131.
2.3 Van Zandt, L. L., "Separation of the Microscopic and Macroscopic Domains", in American Journal of Physics, Vol. 45, No. 1, 1977, p. 55.
2.4 Yurke, B., Stoler, D., "The Dynamic Generation of Schr"dinger Cats and Their Detection", in Physica B, Vol. 151, 1988, p. 300
2.5 Heisenberg, Werner, Physics and Philosophy, the Revolution in Modern Science, New York, Harper and Row, 1966, p. 181-182
2.6 Wigner, Eugene P., "Remarks on the Mind-Body Question", in The Scientist Speculates, New York, Basic Book, 1962, p. 284-302
2.7 Davies, Paul, Other Worlds: A Portrait of Nature in Rebellion Space, Superspace and the Quantum Universe, New York, Simon and Schuster, 1980, p. 133.
2.8 Powers, Jonathan, Philosophy and the New Physics, New York, Methuen, 1982, p. 148.
2.9 Fine, Arthur, "On the Completeness of Quantum Theory", in Logic and Probability in Quantum Mechanics, Boston, D. Reidel, 1976, p. 251.
Chapter1 Contents Chapter 3
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