In my post on the Planck units yesterday, I referenced the work of C. Alden Mead who, as far as I am aware, was the first to take the idea of the Planck units as having a real physical significance out of the realm of folklore. Interestingly, Mead had considerable trouble getting his paper accepted for publication. When I read his paper, I noticed that it was first submitted in June 1959 and must have had multiple exchanges with referees because a revised version was finally received four years later in August 1963 and then it took another year to appear in print in August 1964. The publication of scientific papers can be slow and take about a year or so if accepted but five years means that he had a lot of trouble with referees and had to fight to get it published.

In 2001, Mead recounted his difficulty in getting physicists to take seriously his idea that the Planck length (which he identified as L) played a fundamental role in physics. He said that when he wrote his paper, he had not been aware of Planck’s original proposal for a universal set of units.

I don’t claim that my papers deserved any better fate than they received: years of referee trouble, eventual publication, a cold shoulder from the physics community. But some of the reasons for this cold shoulder are worth noting. At the time, I read many referee reports on my papers and discussed the matter with every theoretical physicist who was willing to listen; nobody that I contacted recognized the connection with the Planck proposal, and few took seriously the idea of L as a possible fundamental length. The view was nearly unanimous, not just that I had failed to prove my result, but that the Planck length could never play a fundamental role in physics.

A minority held that there could be no fundamental length at all, but most were then convinced that a fundamental length L, of the order of the proton Compton wavelength, was the wave of the future. Moreover, the people I contacted seemed to treat this much longer fundamental length as established fact, not speculation, despite the lack of actual evidence for it. Of the people I contacted, the only ones I can recall who had a positive attitude to the idea of L as a fundamental length were Henry Primakoff, David Bohm, and Roger Penrose.

I don’t know when or how the transition of the Planck proposal from heresy to conventional wisdom took place, but I can attest that it had not even begun in the mid-1960s. I suspect that it did not really begin to take hold until at least the mid-1970s, but perhaps others can enlighten me on this.

Why did Mead have so much difficulty? The sketch of the argument that I gave in yesterday’s post was not a rigorous one but designed to give a physical sense of the phenomenon. In his paper, he then went on to provide a more rigorous derivation using the theory of general relativity. I am not competent enough to judge if his argument is correct but general relativists should have been able to make such a judgment and it should have been fairly straightforward.

Part of the reason for rejection may be the normal skepticism that novel ideas generally receive, which is not entirely a bad thing since physics at the frontiers can generate a lot of unusual ideas that turn out to not be viable. The list of the few people who supported him is interesting. In 1959, Penrose had received his PhD only two years earlier and had not achieved the level of recognition for his outstanding abilities that he would get starting with the late 1960s. David Bohm was used to suffering rejection for having unorthodox ideas about quantum mechanics and hence he might have been sympathetic to others struggling against conventional wisdom. But Bohm had been made an outcast during the anti-communist hysteria in the 1950s and ended up an exile in Brazil, after finding it hard to get a job in the US since universities too shunned him. Primakoff was the only one who was a bona fide physics heavyweight in 1959 but his voice alone may have not been enough to sway physicists in favor of Mead’s work.

There is another possibility that Mead does not mention and that is simply the parochial nature of science. When he wrote that paper, Mead was a faculty member in the school of chemistry at the University of Minnesota. Could the referees have been skeptical that a chemist could come up with a novel idea in physics, especially in such an esoteric area of theoretical physics as general relativity? If so, it would not be the first time that scientists in specific fields have been cold to the ideas of ‘outsiders’.

We should always keep in mind that science is practiced by human beings and they can be as prone to the same tribal and parochial instincts as others. But with persistence, as Mead seems to have displayed, that resistance can be overcome.