Sunday, June 18, 2017

Wu Li: Circular reasoning to the max

kw: book reviews, nonfiction, physics, cosmology, buddhism, copenhagen interpretation, quantum mechanics

From time to time I have heard about The Dancing Wu Li Masters: An Overview of the New Physics, by Gary Zukav, since it was published in 1979. I had never read it until now. As a student of all the sciences, particularly the "hard" sciences (those amenable to experimental verification), since before 1960, I have at least a reading familiarity with physics, which is a hard science, and cosmology, which is not. Now having read the book, I find it contains no surprises, at least, none of a scientific nature. Of course, a lot has happened in physics and cosmology in the past nearly forty years.

The author, an admitted outsider to the field of physics, conceived of the book while on a retreat at Esalen along with a real mixed bag of folks including numerous scientists and science hangers-on (some would consider me more of a hanger-on, though I am a working scientist, even in "retirement" from a career in the sciences). Al Huang, who was teaching T'ai Chi at Esalen when Zukav was there, introduced him to the concepts of Wu Li. That is concepts, plural.

I have a great many Chinese friends. The Chinese languages, primarily Mandarin, the principal written Chinese language, abounds in homophones, words that sound the same, at least to a Westerner. Most basic Chinese words consist of one syllable, and very few require more than two syllables. Spoken Chinese sounds to us like a long string of only a few syllables repeated various ways, with a "sing-song" quality that means nothing. What Westerners miss is that the "sing-song" variations in tone are meaningful and are part of the proper pronunciation of Chinese words. Thus, the syllable "MA", depending on the tone, and its context in a sentence, has at least these meanings:

  • Mother.
  • When doubled, an affectionate term for Mother, just as in English, at least when pronounced with two flat tones.
  • Horse, using a different tone.
  • The verb "ride", when the context demands a verb rather than a noun, and using still another tone.
  • The pronounced question mark that ends (nearly) all Chinese questions, spoken with a rising tone.

The familiar greeting "Ni Hao Ma" is a lot like the New Jersey, "How are ya?" The Chinese sentence, "Ma-ma ma ma ma", with the proper string of tones, means, "Is mother riding the horse?" (Chinese has no articles, so "the" is implied).

Depending on tone and context, "WU", pronounced "woo", has about 80 meanings, and "LI", pronounced "lee", has a great many, primarily focused on pattern. Different written Chinese characters (ideographs) are used for the various meanings of wu and li. In combination, the word wu li is the primary Chinese term for "physics". But when other combinations of ideographs with the same pronunciation (except for tones) are used, there are other meanings. In the context of this book, Al Huang gathered five. The literal meaning of the ideographs used for wu li meaning "physics" is "patterns of organic energy". The other four are "my way", "nonsense", "I clutch my ideas", and "enlightenment".

The book is structured around these five concepts, with each section containing two or three chapters. As I might have expected from a book inspired at Esalen, each chapter is numbered 1.

The "new physics" on which the book is centered is quantum mechanics and its relationship to Einstein's theories of relativity (special and general). The core message is the ambiguity of quantum phenomena—when any single "particle" is studied—coupled with the exactitude of the predictions the mathematical theories of quantum mechanics make regarding the statistics of interactions when many particles are subjected to the same set of conditions. The "scripture" of quantum mechanics is the Copenhagen Interpretation, that of Niels Bohr and his followers (I almost wrote "disciples").

Thus, for example, when light is shined through a pinhole, which spreads the beam by diffraction, and this beam is passed through a pair of narrow slits, an interference pattern emerges. This works best when monochromatic light is used, such as from a laser, but "near-mono" filtered light works well enough for visual purposes. The intensity in each part of the interference pattern can be exactly calculated by the Schrödinger wave equation, although the calculations are formidable; various simplifications of the wave equation yield very precise results with less arithmetical grinding.

I mentioned diffraction. This matter is first mentioned on pages 64-65 of the book. In the upper half of an illustration, a series of waves in a harbor are shown exiting a rather broad opening, and those that get through are shown going straight onward, with a sharp edge to their pattern. In the lower half, the opening of the harbor is smaller, and the waves exiting are shown as semicircular wave fronts spreading beyond the opening. There are two major errors here. Firstly, the upper pattern should show a little spreading at the edges of the "beam" of waves exiting the harbor (you can verify this using a wave tank, as I was shown decades ago in a Freshman physics class). In other words, diffraction occurs when waves pass through any opening of any width, not just very narrow ones. Secondly, for the lower wave pattern, the wavelength of the exiting waves is drawn as much shorter than the waves in the harbor.

In actuality, diffraction produces a nonzero probability of the waves at every angle. They seem to "go straight" through a larger opening only because the off-axis waves lose energy with angle very rapidly in such a case. When a wave front passes through an opening of a size similar to the wavelength, or smaller, there are significant amounts that are found at nearly every angle, making a much more divergent beam. Zukav seems to have been ignorant of this.

Interestingly, if a double-slit setup using extra-sensitive photographic film is set up, you can get a surprising result. The best photo film can record the capture of each photon, as long as the light is blue enough, meaning the photons are energetic enough. One silver halide grain is exposed by the capture of a single photon. If the light is dimmed enough that only a few photons per second pass through the apparatus, and you let it run for less than a minute before extracting the film and developing it, the developed film will have one or two hundred tiny exposed grains that are seemingly scattered at random over the film. If instead, you leave the film in place for an entire day, there will of course be many more exposed grains, tens of thousands of them. They will show a very clear interference pattern, identical in form to the one you could see when the light was shining brightly and tens of trillions of photons per second were passing through the apparatus.

Interference is a wave phenomenon. Photons are particles; each carries a specific amount of energy and has a specific momentum (these are all the same for monochromatic light). It took me and all my fellow students a long time to become comfortable with the fact that light has both wave and particle characteristics. Eventually we thought of a photon as a "wavicle", a small wave bundle, that could somehow "sense" that both slits were open and "interfere with itself", when passing through a two-slit apparatus. It seems that light behaves as a wave when wave "behavior" is demanded of it (the two slits), and as a particle when particle "behavior" is required (exposing a silver grain in the film).

Where does Gary Zukav take this, and several other experimental results of quantum mechanics, special relativity, and general relativity? Straight to the door of a Buddhist sanctuary. The language he uses is usually as ambiguous as the language physicists typically use to describe concepts like the "collapse" of a wave function when an "observation" is made. He compares some conclusions and statements of physicists to similar statements of Buddhist doctrine, though I could seldom recognize the resemblance. The core of the Copenhagen Interpretation, at least as it is explained in this book, is that the Observer is central. But, to date, nobody has adequately defined "Observer". That doesn't stop Zukav from equating the one-is-all-all-is-one that he believes the new physics is trending toward to Buddhist teachings of the pre-Christian era. I have a question or two about observers, or Observers.

Must an Observer have a self-aware mind? Can the photographic film described above be an observer, or has no observation been made until the film has been developed and a human (or other self-aware entity) has looked at it to see the pattern? If I understand the Gary Zukav presentation of the Copenhagen Interpretation, there is no "collapse" of the wave function into an actual "event" without an observer. It is as though, outside your peripheral vision, nothing exists until you pay attention to it. Taken to an extreme, it means there was no Universe until humans evolved to be the Observers to bring it into existence. This is the reason for the title of this post. If this is actually what Niels Bohr believed, I have to say to him and his disciples, as Governer Festus long ago said to the Apostle Paul, "Much learning has driven you insane!" Paul was not insane, but I think Zukav might be. More on this anon…

At the time The Dancing Wu Li Masters was being written, some "newer" new physics concepts were arising, such as the Quark/Gluon resolution of the Particle Zoo, and the theory of the Multiverse. To take up the former: It appears that the quark is truly fundamental. All the hadrons seem to be made up of various combinations of quarks and anti-quarks. However, it takes such enormous energies to generate interactions that give evidence of the existence of quarks—and they apparently cannot be brought into independent existence—that we may need to await a particle accelerate wrapped around the equator of the Earth to achieve energies sufficient to determine whether quarks do or do not have any substructure. Apparently, electrons have no substructure, so maybe they and quarks are as fundamental as it gets. But our experiments have reached "only" into the range of 10 to 100 TeV. What might be achieved with an energy a thousand times as great, or a million? Fears have been expressed already that the current experiments at CERN could trigger destruction of the Universe. Maybe the Multiverse is real, and we inhabit a surviving Universe that didn't get destroyed.

The notion of the Multiverse is simple. Rather than the wave function for a particle "collapsing" into some actual event, an entirely random outcome within the statistical framework described by the wave function, perhaps every possible outcome actually occurs, and a new Universe is spawned to contain each of those outcomes. This is simple enough if the "outcome" is that a particular photon passes through either the left slit or the right slit of a two-slit apparatus. Two universes result. I one of them, the photon passes to the left, and in the other, it passes to the right. But there is detail in the interference pattern, and when I have done the experiment with a laser pointer and a home-made pair of slits cut in aluminum foil, I could see more than twenty interference fringes. Now what? Did each photon create twenty or more universes to accompany each outcome? When the light is bright enough to see, trillions of photons per second are "in use"; the beam of my laser pointer emits 200 trillion photons or deep red light per second. Did I inadvertently create a few quadrillion new universes, just by shining my laser pointer through a pair of slits? Were new universes being created at the same rate even when I wasn't looking?

So what are the chances that the search for the Higgs boson at CERN caused the creation of truly enormous numbers of universes, nearly all of which were immediately destroyed, and we inhabit one of those that survived. I think you can see where such thinking can lead.

And some folks say that I am crazy to believe in God, a God who knows a level of physics (if it is called that) that can resolve this stuff, without the insanity of Multiverse speculations. I think it is fair to say that "modern physics" has reached a point of adding more and more epicycles to a group of theories that seem to produce very precise results, but that they are really analogous to pre-Copernican cosmology. Actually, Copernicus used epicycles also, because he thought orbits were based on circles. It took Kepler and others to work that part out.

Another item or two that have arisen in physics since 1979:

  • On page 119 we read, "No one, not one person has ever seen an atom." If you are talking about direct visual sight without the use of a microscope, you could say the same thing about bacteria or viruses. But we have microscopes of several kinds that can show us what they look like in rather amazing detail. Since about 1981, highly refined transmission electron microscopes have been able to show atoms directly, and since the invention in 1982 of the scanning tunneling microscope and the atomic force microscope, we now have three methods for seeing where the atoms lie in a surface. Whatever point the author wished to make based on the above statement is now moot.
  • Beginning on page 292 we find an illustration using polarized light. Simply put, when light is passed through a polarizer (such as the special plastic in some sunglasses), the light that emerges is now all vibrating in the same plane (for convenience, we use the electric vector as the "direction" of polarization, though the magnetic vector could be used equally well, and is at 90° to the electric vector. Zukav does not mention this). When you place a second polarizer with its polarizing axis at 90° to the first, it blocks all the light. If you rotate it to various angles, some of the light gets through, in accordance with an elliptical formula. Now, if you set the two polarizers so their polarization axes are at precisely 90° so that no light is getting through, then put a third polarizer between them, with its axis oriented at 45° to the other two, quite a lot of light gets through! This goes on for several pages and is presented as quite a mystery. Strangely, elsewhere in the book we find the tools to solve this mystery (I didn't look up page numbers):
    • In a discussion of Feynman Diagrams and the S-Matrix (Scattering Matrix) we read that physicists consider every interaction to entail the destruction of all the impinging particles and the creation of new ones that exit the interaction locus at the appropriate angles with appropriate velocities. Thus, when a photon reflects off a mirror or any shiny surface, it is actually absorbed and a new photon is released at the appropriate angle. So they say. Refraction works similarly. Thus, the polarizer absorbs the incoming photons and releases a somewhat smaller number of photons, all with the appropriate polarization.
    • As I recall, a polarizer made of stretched plastic film passes 38% of the original light. A Nicol prism can actually split light into two beams with nearly no loss, so that 50% exits with horizontal polarization at one angle, and 50% with vertical polarization at a different angle. This would make no sense according to the "picket fence" analogy, because very, very little of the original light could get through any polarizer: only that which is already polarized the "right" way. Thus, a Nicol prism, in particular, "tests" each photon, and either twists its polarization to match the nearest direction (and shifting its exit angle according to the one or the other), or annihilates the photon and emits one of appropriate polarization and exit angle.
    • Polarizing plastic is less efficient, passing only light of one polarization, but obviously changing whatever the polarization was of most photons to match its orientation. Thus, what is happening with the 45° polarizer is this: it absorbs some photons entirely, and twists the polarization of the rest of them by 45°. Then when they reach the last polarizer, they are now subject to a further absorption or twisting, so that the "twisted ones" get through, with perhaps 5% of the original beam intensity. That is a lot more than the fraction of a percent that "sneaks through" the original set of crossed polarizers because plastic film polarizers are not perfect.
    • So polarizing devices do not just passively allow certain photons to pass and block all others, but they change the polarization of the photons that they allow to pass.
  • I cannot pass by the chance to mention circular polarization. A thin piece of calcite or quartz (or, indeed, any colorless crystalline material that does not have cubic molecular symmetry) rotates the polarization of the incoming light. What is more, if it is just the right thickness, it will produce circularly polarized light. This is sometimes thought of as two streams of photons that are related to one another. Think of a vertically polarized photon coupled with a horizontally polarized photon, and their "waves" are out of phase by a quarter of a wavelength. Then, in effect, their polarization will rotate as the go.

As interpreted by Gary Zukav, physics was becoming one with Buddhism. I wonder what he would make of today's situation, with the great popularity among physicists of cosmological string theories (at the moment, they can't decide which of the potential 10500 possible string theories to favor!), the supposed detection of increasing cosmological expansion that may lead to a "big rip" in which all things will be literally shredded to their composite quarks, and the theory of cosmological inflation (developed in the early 1980's) that supposes that the initial expansion of the big bang took off at several trillion trillion trillion times the speed of light for just a tiny fraction of a second, during which the Universe grew to a size somewhere between that of a grapefruit and a galaxy (nobody can pin that down too precisely).

In my view, coupling physics theorizing with Buddhism is tantamount to solipsism. Let us accept as a first premise that what exists, does indeed exist, and go from there. Then the extreme versions of "New Physics" simply vanish, like an unobserved photon.

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