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I was (for my sins) reading back issues of the American Spectator in the Berkeley library, and I came across a marvelously funny column by its Washington correspondent, Tom Bethell: "Doubting Dada Physics," in the August 1993 issue (pp. 16-17). The column's subject is:
...[a] solitary genius [Petr Beckmann]... publish[ing] his own ideas and discoveries at a time of growing intellectual corruption in the academy... [who] undermined Einstein's theory of relativity, and... show[ed] how physics could be returned to the classical foundation from which it was dislodged at the beginning of the twentieth century.
Now three things make the column funny:
- Relativity was not the most important disruption of "classical" nineteenth-century physics. Quantum mechanics provoked a much bigger and much spookier revision of the classical and common sense world view. From Bethell's perspective--given his ultimate political goal--he is shooting at the wrong target.
- Special relativity is one of the best-confirmed theories in history. Every time you run an electric motor, every time a cosmic ray particle falls from the sky, every time physicists fire up a particle accelerator, every time you use the Global Positioning System to figure out where you are, you confirm special relativity. Theories that "disagree" with special relativity do so only around its very edges, by making different predictions about the results of experiments that cannot have been run yet, or that we will never be able to run.
- Our intuitions about time and space are derived from our own experience, living as we do on a planet and moving at velocities much, much lower than the speed of light. It makes little sense for Bethell to raise these intuitions to the status of "the most basic precepts of science... the alpha and omega of the material world--the irreducible character of time and space": as little sense as it would for someone living on the great plains to deny the existence of oceans.
It is not clear to me from Bethell's column whether Beckmann understands relativity or not; it is clear that Bethell does not understand what he is attacking--and that he is attacking it because of what he presumes are the moral and political implications of relativity physics. He is thus in the position of saying the opposite of Galileo--instead of "And yet it moves," he is closing his eyes to a huge amount of experimental evidence and saying, earnestly if incoherently, "and yet it stands still."
But there are unfunny parts to the column as well.
First, conservatives who dislike Einstein do so for one of two reasons:
- Because the admission that measurements of time and space depend on the motion of the observer is in their minds' somehow tied up with the erosion of traditional cultural "absolutes," and scientific truth should be sacrificed to cultural order whenever necessary. In Bethell's article is a whiff of the silencing of Galileo Galilei, the burning of Giordano Bruno, or Trofim Lysenko's sending Russian geneticists to the GULAG: you get the sense that Bethell would be opposed to the teaching of relativity even if he believed it was true.
- Because Einstein was a Jew: the meme of anti-Einstein thought in modern conservatism is a legacy of anti-semitism.
- Opposition to relativity for politico-cultural reasons and opposition to relativity as a legacy of anti-semitism are usually inextricably mixed. Neither is attractive. In Bethell's article, you can see: (i) the hint that Einstein's purpose in proposing his obviously absurd theory was to attack traditional cultural and aesthetic forms; (ii) the hint of a conspiracy of silence among physicists to prop up Einstein's reputation for sinister purposes; (iii) the claim that relativity's attraction to "intellectuals" arises because it is "abstruse... deliciously disrespectful... marvelously baffling to the bourgeoisie." All three of these have roots in anti-semitic visons of the secret conspiracy of over-clever but deceptive Jews--"rootless cosmopolitans" who lack the earthy common sense and grounding in the soil of the Volk--out to undermine the faith and social order of the simple Christian folk.
Second, Bethell spends most of his time as a political columnist--and his political judgment is as bad as his scientific.
I've attached the bulk of the column below. Statements that are simply wrong are in red.
...[a] solitary genius [Petr Beckmann]... publish[ing] his own ideas and discoveries at a time of growing intellectual corruption in the academy. Above all, he is likely to be remembered for having undermined Einstein's theory of relativity, and for showing how physics could be returned to the classical foundation from which it was dislodged at the beginning of the twentieth century.
Ever since he learned relativity theory, Beckmann felt there must be something wrong with it. when he retired from teaching, he returned to the subject, spending several years on a book called Einstein Plus Two. He now believes that relativity theory "has been confirmed only in a narrow sector of physics, leads to logical contradictions, and is unable to derive results that must be postulated, though they are derivable by classical methods." He also believes that the theory is definitely falsified by the aberration of light from binary stars....
The problem that Einstein tried to solve, the new problems that arose with his solution, and Beckmann's brilliant resolution of all these difficulties, are not so difficult as they may sound. In fact, mystification has greatly enhanced Einstein's reputation. I hasten to add that Beckman is a great admirer of Einstein, whose famous equation of energy and mass, E=MC-squared, is unaffected by all this; in fact, it was derived independently of relativity.
By the mid-nineteenth century, the evidence that light travels in waves had become overwhelming [in fact, light travels in particles--individual packets--photons*]; wave theory accounted for refraction, polarization, and many other phenomena of light. The great puzzle was to understand what medium it travels in. Sound needs air; light needs... what? It can travel through a vacuum, through interstellar space. But if it is a wave, there must be an oscillating medium, [but because it isn't a wave, the problem doesn't arise] however rarified. The medium was called the "ether" and the great challenge for nineteenth-century physicists was to detect it.
The most famous experiment was carried out by Michelson and Morley in 1887. Since the earth must be moving through this ether in its orbit around the sun, it should be possible to detect an "ether wind," just as it is possible to feel the wind by putting your hand out a moving car. Albert Michelson, the first American to win the Nobel Prize in physics, designed the apparatus to measure it. But despite repeated attempts, no ethereal breeze could be detected.... This "null result" threw the world of physics into disarray. A wave without a medium!
Enter Einstein, fresh from the Bern patent office. He posited that there was no medium, and that the speed of light is the same in all directions irrespective of the motion of any apparatus set up to detect it. His famous 1905 paper, setting forth the special theory of relativity, demonstrated that if these odd assumptions are made, everything can be shoe-horned in mathematically. But it was odd. If a sound wave moves toward you at 750 miles an hour, and you walk towards it at 5 mph, you will detect the sound approaching at 755 miles an hour [you will not: the speed will be slower than 755 mph because of relativistic effects, but only infinitesimally slower because your speed is infinitesimal (one six hundred millionth or so) relative to the speed of light]. Observation agrees with common sense. The same is true of all other waves one can think of. But not electromagnetic phenomena (including light), said Einstein [relativity applies to all relative motion, whether involving electromagnetism or not]. The velocity of light was accorded a privileged, absolute status. Move toward the light source, and you will detect the light approaching you at the same speed as someone who is standing still.
That was where the absurdity came in. To preserve the absolute nature of the speed of light, space and time had to be distorted. Two twins are the same size: If A moves, he see B smaller than himself. But B likewise sees A as smaller than himself. Which is absurd. Reality becomes observer-dependent, [reality is still there, and is unchanged: any observer can easily figure out what the time and space perceptions of any other observer are] in opposition to the most basic precepts of science. The alpha and omega of the material world--the irreducible character of time and space--were sacrificed in order to preserve an absolute velocity [how would anyone know that intuitions about the irreducible character of time and space acquired while always moving at velocities so low that relativistic effects are infinitesimal would still apply to high-velocity situations?]. But velocity is nothing but space (distance) divided by time! This was Dada Physics. (It's interesting that the Dada movement "having as its program the discovery of authentic reality through the abolition of traditional cultural and aesthetic forms," came right after the general relativity theory .)
Beckmann says that most students of physics shrug and accept relativity theory--theirs is not to quarrel with the sainted genius of the twentieth century. Some have private reservations. Among intellectuals in general, the theory has been much admired: so abstruse, so deliciously disrespectful of the eternal verities, so marvelously baffling to the bourgeoisie. It doesn't interfere with the daily routine, makes no practical difference to the Newtonian world. [it makes a big difference: to understand why a magnetic field exerts a force on a moving but not a stationary electron requires special relativity]. But it does upset its theoretical underpinnings. Wonderful! The Muddled Majority who fell so reassured by their common-sense understanding of the world just don't realize that things aren't what they seem to be at all.
Pondering the theory in the late 1950s at Prague's Institute of Radio Engineering, Beckman concluded that there had to be a medium for light, and in an offhand comment, a student named Pokorny, a (then) devout Communist, suggested the correct answer, as Beckmann is now convinced: the medium for electromagnetic waves is the local gravitational field--dense near the sun, attenuated in outer space [this does give rise to a problem: there are gravitational waves: what is their "oscillating medium"?]. On Earth, the local field is that of the Earth itself. The point is, the Earth's gravitational field moves along with the earth. So that was why Michelson-Morley could detect no ether wind. It was like sitting in a jet as it goes down the runway, holding a toy propeller in your lap and expecting the wind to turn the blades. Absurd--the air in the cabin is moving forward with the plane.
But wait! The earth also rotates on the axis, and there is good reason to think that the gravitational field does not go around with the Earth. Imagine this field as a hoop skirt on a woman with a circular waist. As she walks forward the skirt moves with her. But then, as she walks, she pirouettes, and now her body will slip around inside the skirt.
If this analogy is correct, the Michelson-Morley experiment might have been able to detect a fringe-shift after all--but a much smaller one.... It could easily be detected on the space shuttle, because the shuttle goes through the gravitational field much faster than the Earth....**
*There is a quantum amplitude associated with each photon's possible paths and interactions: there is a quantum amplitude associated with every particle's possible paths and interactions. The propagation and interference of the quantum amplitude give rise to interference, and other "wave-like" phenomena. But there is nothing special about the behavior of light as opposed to, say, electrons.
** Bethell goes on to say that the fact that light travels from New York to San Francisco faster (by about 40 nanoseconds) than from San Francisco back to New York is experimental disproof of relativity. He is, of course, wrong. This "puzzle" is, however, of some interest because it shows that our instruments are now so sensitive that even the rotation of the earth leads special relativity to make a difference that we can measure. In the frame of reference of the center of the earth light travels from New York to San Francisco faster than from San Francisco to New York because the earth is spinning: in the time it takes light to go from New York to San Francisco, the earth's rotation has carried San Francisco about twenty feet toward New York. In the frame of reference of the center of the earth light travels from New York to San Francisco faster than back the other way because the New York to San Francisco leg covers a shorter distance.
In a frame of reference moving with New York and San Francisco during the 1/30 of a second that it takes light to go from one to the other and back, the two journeys take equal times and cover equal distances. How is this possible? Because for any "now" in New York, the corresponding "now" in San Francisco is an event taking place 20 nanoseconds earlier in the moving frame of reference than is the "now" in the center of the earth frame. In 20 nanoseconds a modern 200-megahertz computer chip processes four instruction cycles.
So does light go from New York to San Francisco in a shorter time than it comes back, or doesn't it? From the perspective of the global positioning system--which uses a center-of-the-earth based frame of reference--the answer is "yes." From the perspective of the frame of reference of the guy-in-New York, the answer is "no."
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