Call it my guilty little secret. Every now and then, I enjoy nothing more than picking up a work of crackpot science, reading it with the irony lobe engaged, and figuring out precisely where the author went off the rails and trying to imagine how one might explain to them the blunders which led to the poppycock they expended so much effort getting into print. In the field of physics, for some reason Einstein’s theory of special relativity attracts a disproportionate number of such authors, all bent on showing that Einstein was wrong or, in the case of the present work’s subtitle, asking “Is Relativity Necessary?”. With a little reflexion, this shouldn’t be a surprise: alone among major theories of twentieth century physics, special relativity is mathematically accessible to anybody acquainted with high school algebra, and yet makes predictions for the behaviour of objects at high velocity which are so counterintuitive to the expectations based upon our own personal experience with velocities much smaller than that they appear, at first glance, to be paradoxes. Theories more dubious and less supported by experiment may be shielded from crackpots simply by the forbidding mathematics one must master in order to understand and talk about them persuasively.
This is an atypical exemplar of the genre. While most attacks on special relativity are written by delusional mad scientists, the author of the present work, Tom Bethell, is a respected journalist whose work has been praised by, among others, Tom Wolfe and George Gilder. The theory presented here is not his own, but one developed by Petr Beckmann, whose life’s work, particularly in advocating civil nuclear power, won him the respect of Edward Teller (who did not, however, endorse his alternative to relativity). As works of crackpot science go, this is one of the best I’ve read. It is well written, almost free of typographical and factual errors, clearly presents its arguments in terms a layman can grasp, almost entirely avoids mathematical equations, and is thoroughly documented with citations of original sources, many of which those who have learnt special relativity from modern textbooks may not be aware. Its arguments against special relativity are up to date, tackling objections including the Global Positioning System, the Brillet-Hall experiment, and the Hafele-Keating “travelling clock” experiments as well as the classic tests. And the author eschews the ad hominem attacks on Einstein which are so common in the literature of opponents to relativity.
Beckmann’s theory posits that the luminiferous æther (the medium in which light waves propagate), which was deemed “superfluous” in Einstein’s 1905 paper, in fact exists, and is simply the locally dominant gravitational field. In other words, the medium in which light waves wave is the gravity which makes things which aren’t light heavy. Got it? Light waves in any experiment performed on the Earth or in its vicinity will propagate in the æther of its gravitational field (with only minor contributions from those of other bodies such as the Moon and Sun), and hence attempts to detect the “æther drift” due to the Earth’s orbital motion around the Sun such as the Michelson-Morley experiment will yield a null result, since the æther is effectively “dragged” or “entrained” along with the Earth. But since the gravitational field is generated by the Earth’s mass, and hence doesn’t rotate with it (Huh—what about the Lense-Thirring effect, which is never mentioned here?), it should be possible to detect the much smaller æther drift effect as the measurement apparatus rotates around the Earth, and it is claimed that several experiments have made such a detection.
It’s traditional that popular works on special relativity couch their examples in terms of observers on trains, so let me say that it’s here that we feel the sickening non-inertial-frame lurch as the train departs the track and enters a new inertial frame headed for the bottom of the canyon. Immediately, we’re launched into a discussion of the Sagnac effect and its various manifestations ranging from the original experiment to practical applications in laser ring gyroscopes, to round-the-world measurements bouncing signals off multiple satellites. For some reason the Sagnac effect seems to be a powerful attractor into which special relativity crackpottery is sucked. Why it is so difficult to comprehend, even by otherwise intelligent people, entirely escapes me. May I explain it to you? This would be easier with a diagram, but just to show off and emphasise how simple it is, I’ll do it with words. Imagine you have a turntable, on which are mounted four mirrors which reflect light around the turntable in a square: the light just goes around and around. If the turntable is stationary and you send a pulse of light in one direction around the loop and then send another in the opposite direction, it will take precisely the same amount of time for them to complete one circuit of the mirrors. (In practice, one uses continuous beams of monochromatic light and combines them in an interferometer, but the effect is the same as measuring the propagation time—it’s just easier to do it that way.) Now, let’s assume you start the turntable rotating clockwise. Once again you send pulses of light around the loop in both directions; this time we’ll call the one which goes in the same direction as the turntable’s rotation the clockwise pulse and the other the counterclockwise pulse. Now when we measure how long it took for the clockwise pulse to make it one time around the loop we find that it took longer than for the counterclockwise pulse. OMG!!! Have we disproved Einstein’s postulate of the constancy of the speed of light (as is argued in this book at interminable length)? Well, of course not, as a moment’s reflexion will reveal. The clockwise pulse took longer to make it around the loop because it had farther to travel to arrive there: as it was bouncing from each mirror to the next, the rotation of the turntable was moving the next mirror further away, and so each leg it had to travel was longer. Conversely, as the counterclockwise pulse was in flight, its next mirror was approaching it, and hence by the time it made it around the loop it had travelled less far, and consequently arrived sooner. That’s all there is to it, and precision measurements of the Sagnac effect confirm that this analysis is completely consistent with special relativity. The only possible source of confusion is if you make the self-evident blunder of analysing the system in the rotating reference frame of the turntable. Such a reference frame is trivially non-inertial, so special relativity does not apply. You can determine this simply by tossing a ball from one side of the turntable to another, with no need for all the fancy mirrors, light pulses, or the rest.
Other claims of Beckmann’s theory are explored, all either dubious or trivially falsified. Bethell says there is no evidence for the length contraction predicted by special relativity. In fact, analysis of heavy ion collisions confirm that each nucleus approaching the scene of the accident “sees” the other as a “pancake” due to relativistic length contraction. It is claimed that while physical processes on a particle moving rapidly through a gravitational field slow down, that an observer co-moving with that particle would not see a comparable slow-down of clocks at rest with respect to that gravitational field. But the corrections applied to the atomic clocks in GPS satellites incorporate this effect, and would produce incorrect results if it did not occur.
I could go on and on. I’m sure there is a simple example from gravitational lensing or propagation of electromagnetic radiation from gamma ray bursts which would falsify the supposed classical explanation for the gravitational deflection of light due to a refractive effect based upon strength of the gravitational field, but why bother when so many things much easier to dispose of are hanging lower on the tree. Should you buy this book? No, unless, like me, you enjoy a rare example of crackpot science which is well done. This is one of those, and if you’re well acquainted with special relativity (if not, take a trip on the C-ship!) you may find it entertaining finding the flaws in and identifying experiments which falsify the arguments here.
Bethell, Tom. Questioning Einstein. Pueblo West, CO: Vales Lake Publishing, 2009. ISBN 978-0-971-48459-7.