It is easy to assume that scientific crankery is a relatively new phenomenon, perhaps fueled by the completely non-intuitive, sometimes intimidating nature of many modern scientific theories. In physics, for instance, most cranks spend their time attacking Einstein’s theories of relativity and the theory of quantum mechanics, both of which go against “common sense.”
While browsing the older journals, however, I came across an example of crankery from 1891, well before the advent of “modern” physics! The crankery practically jumped off the page at me as I was skimming the table of contents in the Philosophical Magazine. An image of the page in question is below; see if you can spot what caught my eye (click to enlarge):
Does anything strike you?
(Here I skip a few lines so you don’t accidentally read the answer first)
The single word that jumped out at me while skimming the titles was the word, “absurdity”, in J. Parker’s “Theory of magnetism and the absurdity of diamagnetic polarity.” Clearly “absurd” is a very negatively charged and polemical word; Merriam-Webster defines it as, “ ridiculously unreasonable, unsound, or incongruous.” Though scientists will freely use such words in spoken arguments with colleagues (I’ve heard, and used, far worse in discussions with collaborators), it is generally unprofessional to use such insults in printed papers, and a sign of someone who is motivated by emotion, not reason.
The scientific topic at issue is diamagnetism, which I’ve discussed at length in a previous post. When a changing magnetic field B is applied to a material, a circulating electric field is induced via Faraday’s law which increases the orbital speed of the electron:
In turn, this means that the material becomes magnetized, and it produces a magnetic field which opposes the applied field. Such a material is known as diamagnetic.
There is a complementary effect called paramagnetism, in which a magnetic field is produced which increases the applied field. All materials are to some extent diamagnetic, though in most materials the effect is so weak that a very strong magnet must be applied to produce a noticeable effect. Paramagnetic materials are much less common, but the effect is much stronger and easier to detect.
By their nature, paramagnetic materials are drawn towards stronger magnetic fields, while diamagnetic materials are drawn away from stronger fields:
This difference will be important to our discussion; the repulsion of diamagnets is what makes diamagnetic levitation possible.
Diamagnetism was discovered in 1778 by S.J. Bergman, but the most groundbreaking research was done by Michael Faraday (who else?) in 1845, who discovered the universal existence of diamagnetism in matter. By the late 1880s, diamagnetism was quite well established as a real physical phenomenon, albeit one whose origin was poorly understood.
Enter J. Parker, fellow of St. John’s College, Cambridge1. His first foray into diamagnetism was published in the Philosophical Magazine in 1889 with the title, “On diamagnetism and the concentration of energy.” This paper argues from thermodynamic principles that something is very strange about the idea of diamagnetism.
Parker suggests the following scenario, which sounds reasonable on a first glance:
- Imagine you have a permanent magnet P, and a diamagnetic material D. Suppose you slowly bring the diamagnet from a point A distant from P to a point B close to P. As you bring the diamagnet close, the material will become ‘anti-magnetized’, and you will have to do some amount of work W to bring the magnet to B. You can reverse the process and let the magnet be pushed away slowly from B to A, which should then release the same amount of work from the magnetic system.
- Now suppose you bring the diamagnet D towards the permanent magnet really fast, so fast that the material doesn’t have time to respond to the field of the permanent magnet P. Since the diamagnetic material hasn’t responded yet, it will take a smaller amount of work W'< W to move the magnet to point B. While at B, the diamagnet has time to become fully ‘anti-magnetized’, and when it is released to return to A, it releases an amount of work W.
By the second scenario, it seems that energy has been created; we expend an amount of energy W’ to get back an amount of energy W>W’. Parker suggests that this conundrum can be resolved only one of three ways: (a) conservation of energy is violated, and we get something from nothing, (b) the diamagnet D becomes ‘anti-magnetic’ instantaneously when brought to the magnet P, with an unstated assumption that somehow the constituent matter of D is rearranging itself instantaneously, or (c) the energy is drawn from the diamagnet in the form of heat, thus making the diamagnet cooler without any other variations of temperature in the system, thus violating Carnot’s principle.
If (a) or (c) is true, one could make a perpetual motion machine from a diamagnet. Imagine a pendulum made of diamagnetic material being allowed to swing towards a permanent magnet, as illustrated below:
If the pendulum speed is fast enough when approaching the magnet, it will lose energy W’ to approach the diamagnet, but will gain back energy W on the rebound! Even if it cools off in the process, it will readily gain heat from the surrounding air and will be able to repeat the process indefinitely, becoming, in essence, an infinite source of energy. The reasoning is wrong, however; we’ll point out why in a moment. (See if you can figure it out before then — it’s not obvious!)
In 1890, Parker published another paper in the Philosophical Magazine titled, “Diamagnetism tested by Carnot’s principle.” In this short paper, he essentially postulates that the arguments of his previous paper are insurmountable, and the only conclusion is that diamagnetism does not exist! He provides an alternative explanation of the observed repulsion which, on its face, also appears reasonable: Supposing the air surrounding the diamagnet can be magnetized, and is paramagnetic, then there would be a higher air pressure in the vicinity of the permanent magnet, which would tend to push the diamagnet away:
This argument is also incorrect, though we’ll return to this in a moment as well. It is worth pointing out that these two early papers by Parker are non-confrontational, and possess arguments which, even though now known to be incorrect, seem somewhat reasonable. What happened to turn Parker from moderate scholar to angry crank blasting the “absurd” concept of diamagnetism?
In Parker’s own words, from part I of his 1891 paper,
My second paper on diamagnetism was criticised, as I have since found, by Dr. Lodge with a great display of rhetoric in the next number of the Philosophical Magazine; but I was then so occupied that I did not see or hear of the criticism until the following November. When I then came to read it, I did not find anything which required me to modify any of my ideas on the subject in the slightest degree, and I concluded that Dr. Lodge had misunderstood my paper.
Ah! It seems that harsh criticism turned Parker from confused man to dogmatic monster! In August 1890, Oliver J. Lodge published a short letter harshly criticizing Parker’s musings. The paragraph above suggests that Parker’s ego was heavily bruised by Lodge’s criticisms, and in response he further hardened his own views on the subject. The result is reminiscent of the examples of crankery in Bob Park’s classic book Voodoo Science, in which honest mistakes and misunderstandings are morphed by arrogance and self-interest into outright deception.
Lodge’s letter was rather brutal and didn’t help matters:
In the May 1889 number of the Philosophical Magazine Mr. J. Parker states a series of propositions which are equivalent to the invention of an ingenious perpetual-motion machine…
Returning to the subject in the last number of the Philosophical Magazine (July 1890), he emerges from this position to make the still wilder suggestion that diamagnetism does not really exist; that Faraday was deceived throughout his long and acute investigation by the obviously disturbing and constantly guarded-against paramagnetism of the air!
In fairness, Lodge’s letter is rather unconvincing itself. He suggests that the permanent magnet might be being demagnetized by the action of the diamagnet, thus invalidating Parker’s argument. This is reasonable, but sounds rather defensive. Lodge’s appeal to authority, namely Faraday, is also rather weak, though it suggests a good guideline: if two years of musings convince you that a brilliant experimentalist like Faraday was completely wrong over a decade of research, perhaps you should rethink your own musings!
This appeal to authority was not missed by Parker, who complained at the end of part 1 of his “absurdity” paper:
To conclude our discussion on diamagnetism, I observe that, so far as I am aware, no one has ever attempted to advance any serious theoretical or other arguments in favour of the common notion of diamagnetism… Even in England there are persons who have never accepted it, and Dr. Lodge himself seems to be aware that it will not stand examination; for in his criticism on my two previous papers on the subject, he appears to rely chiefly on the strength of his rhetoric, and on an appeal to the name of Faraday.
Parker looks to have the upper hand here. The theory of diamagnetism was not particularly well established; as I’ve noted many times before, the structure of the atom would not be known for another 20 years, and a rigorous theory of diamagnetism would be difficult to construct without that knowledge. As we will see, however, Parker is not only wrong, but completely wrong.
It would seem that there are no heroes in this story! But another physicist would come to save the day: George FitzGerald, who is best known for proposing the relativistic idea of length contraction, which we discussed in a recent post. FitzGerald provided an absolutely devastating “Editorial note on Mr. Parker’s paper on the absurdity of diamagnetism,” which is worth reproducing in full:
If I had seen Mr. Parker’s paper in last month’s Philosophical Magazine before publication, I would have referred it back to him for some important alterations. I could hardly, however, have foreseen, when publishing a paper by a Fellow of St. John’s College, Cambridge, that it was likely to contain such statements as, 1st, that there is anything new in the theory that diamagnetic action is really due to the paramagnetism of the air; and, 2nd, that no theory of diamagnetic action has been propounded. This “new theory” is at least as old as Becquerel (1850), and has been investigated by almost everybody who has worked at diamagnetism, and they are practically unanimous in the conclusion that diamagnetic actions cannot be explained by the paramagnetism of the air.
These undisputed experiments prove that such a theory as Becquerel’s would require a vacuum to be paramagnetic. This is a new nomenclature, and does not make the old one absurd; it involves practically what Mr. Parker says is non-existent, namely one of the theories of diamagnetism. But all this is too well known to be worth wasting words on.
As to the second curious statement of Mr. Parker’s, namely that no theory of diamagnetism exists, that is equally extraordinary. Chapter xxii. of Maxwell’s pretty generally known Treatise is headed “Ferromagnetism and Diamagnetism explained by Molecular Currents,” and gives an interesting description of Weber’s theory of Diamagnetism in §838. If Mr. Parker had exercised his ingenuity in explaining how Weber’s theory, which, being a possible theory can be reconciled with Thomson’s difficulty, it would have been more instructive than a dissertation on the absurdity of what undisputed experiments show to be real. If the opoprtunity had arisen, it would have been only kind to Mr. Parker to have referred the paper back to him for reconsideration before publishing it.
Ouch! In short, Parker was completely ignorant of the experimental and theoretical work on diamagnetism over the previous forty years. A number of theoretical approaches had been proposed, more or less in line with the classical description I gave at the beginning of this post. In experimental physics, the idea that magnetized air is responsible for diamagnetism had been considered and conclusively discounted a long time earlier.
Curiously, Parker seems to have been aware of such experiments but discounted them:
The preceding calculations may well throw doubt on the common theory of diamagnetism, but the theory has still one apology left. It is found that diamagnetic bodies retain their characteristic property in a comparative “vacuum” of 2 or 3 millimetres of mercury (say the 1/300th of an atmo). To explain this, we have only to observe that if, in our ideal experiment, the attraction of the pole P on the body M were strictly zero, the body M would be driven away from the excited pole P by the pressure of the air however good the “vacuum” might be, short of absolute perfection. Hence if the attraction of P on M be not strictly zero but exceedingly small, it will be necessary to reduce the density of the air very nearly to zero before this attraction can make itself manifest.
Physicists had shown that placing the diamagnet in a partial vacuum had no effect on the relevant forces. To most, this would imply that air had no effect on diamagnetism. Parker ignores this and claims that there would be no change unless the vacuum were perfect! He also seems to give no ready explanation of why different materials would have different air pressure forces acting on them.
So what is the resolution of “Parker’s paradox”? My impression is that his flaw is in the argument that the diamagnet can be moved so quickly that there is no immediate diamagnetic response. By Faraday’s law of induction, a circulating electric field is created by a changing magnetic field. The change of the magnetic field in our case is provided by the motion of the diamagnet towards the permanent magnet. The faster we move our diamagnet, the stronger the electric field which is induced, and the faster the electrons are accelerated in the material. The magnetic field acts, in effect, like a hill that the diamagnet must climb. The notion that we can move fast enough to ignore the magnetic field response is comparable to say that we can ignore gravity if we drive over a hill fast enough! 2
This may still be an oversimplified explanation; the magnetic properties of materials are quite complicated. I would say that Parker’s major mistake was making assumptions about the microscopic behavior of the diamagnetic materials, and then drawing broad, hard conclusions from those assumptions. We have previously seen what troubles this can cause: the famous Abraham-Minkowski paradox concerning the momentum of light in matter arises in essence because it ignores the microscopic behavior of matter.
In the end, Parker showed many of the classic traits of a crackpot: he relied on arguments based on “plausibility”, he discounted experimental evidence, and didn’t bother to learn the literature. It is somehow reassuring to realize that crackpots not only are, but have been and probably always will be.
1 I was unable to find any other information on Mr. Parker, who seems to have gone silent after his diamagnetic tirade.
2 For those smart-asses who are sure to point it out, I am well aware that if one goes fast enough, one can go right through the hill and skip the climb!