Given the recent Feynman explosion (timeline of events), some people may be casting about looking for an alternative source of colorful-character anecdotes in physics. Fortunately, the search doesn’t need to go all that far– if you flip back a couple of pages in the imaginary alphabetical listing of physicists, you’ll find a guy who fits the bill very well: Enrico Fermi.
Fermi’s contributions to physics are arguably as significant as Feynman’s. He was the first to work out the statistical mechanics of particles obeying the Pauli exclusion principle, now called “fermions” in his honor (Paul Dirac did the same thing independently a short time later, so the mathematical function is the “Fermi-Dirac distrbution“). He was also the first to develop a theory for the weak nuclear interaction, placing Wolfgang Pauli’s desperate suggestion of the existence of the neutrino on a sound theoretical footing. Fermi’s theory was remarkably successful, and anticipated or readily incorporated the next thirty-ish years of discoveries.
More than that, he was a successful experimental physicist. He did pioneering experiments with neutrons, including demonstrating the fission of heavy elements (though he initially misinterpreted this as the creation of transuranic elements) and was the first to successfully construct a nuclear reactor, as part of the Manhattan Project. The US’s great particle physics lab is named Fermilab in his honor.
One of the difficult things about replacing Feynman is that a lot of the genuinely admirable things about his approach to physics are sort of bound up with his personality. Meaning that it’s easy to slide from approach-to-physics stuff– spinning plates at Cornell, etc.– to relatively wholesome anecdotes– dazzling off-the-cuff calculations, cracking safes at Los Alamos– into the strip clubs and other things that make Feynman a polarizing figure.
Fermi brings a lot of the same positive features without the baggage. He had a similarly playful approach to a lot of physics-related things– the whole notion of “Fermi problems” and back-of-the-envelope calculations is pretty much essential to the physics mindset. Wikipedia has a great secondhand quote:
I can calculate anything in physics within a factor 2 on a few sheets: to get the numerical factor in front of the formula right may well take a physicist a year to calculate, but I am not interested in that.
He was also a charming and witty guy, with a quirky sense of humor (the photo above has a mistake in one of the equations, and people have spent years debating whether that was deliberate, because it’s the kind of thing he might’ve done as a joke on the PR people). He even has his own great Manhattan Project anecdotes– he famously estimated the strength of the blast by dropping pieces of paper and pacing off how far they blew when the shock wave hit, and prior to the Trinity test was reprimanded by Oppenheimer for running a betting pool on whether the test would ignite the atmosphere and obliterate life on Earth.
He also has the wide-ranging interests going for him. His name pops up all over physics, from statistical mechanics to the astrophysics of cosmic rays. And just like Feynman is more likely to be cited in popular writing for inspiring either nanotechnology or quantum computing than for his work on QED, Fermi’s true source of popular immortality is that damn “paradox” about aliens.
While the personal anecdotes may not quite stack up to those about Feynman, there isn’t the same dark edge. Fermi was happily married, and in fact moved to the US because of his wife, who was Jewish and subject to the racist policies put in place by Mussolini (they left directly from the Nobel Prize ceremony in 1938, where Fermi picked up a prize for work done in Rome). I’m not aware of any salacious Fermi stories, so he’s much safer in that regard.
Given all that, why is Fermi so much less well-known than Feynman? Partly because a lot of his contributions to physics were excessively practical– experimentalists tend to be less mythologized than theorists, and his greatest theoretical contributions came through cleaning up ideas proposed by Pauli. Mostly, though, it’s because he was a generation older than Feynman and died younger, in 1954. He never got the chance to be a grand old man, and didn’t live into the era where the sort of colorful anecdotage that so inflates Feynman’s status became popular. Had he lived another twenty years, things might’ve been different.
(It’s also interesting to speculate about what Schrödinger’s reputation would be had he been closer to Feynman’s age than Einstein’s. Schrödinger would’ve loved the Sixties, between his fascination with Vedic philosophy and the whole “free love” thing. But had he been alive through then, the skeevy aspects of his personal life would probably be better known, because most of his more sordid activities took place in an era when people didn’t really talk about that sort of thing in public, let alone write best-selling autobiographies about it.)
Anyway, that’s my plug for Fermi. If you find Feynman too problematic to promote– and that’s an entirely reasonable decision– Fermi gets you a lot of the same good stuff (great physicist, playful approach to science, charming and personable guy), without the darker side. He should get more press.
(That said, Fermi is one of the figures I regret not being able to feature more prominently in the forthcoming book. The problem is, the focus of the book is on process, and Fermi’s one of those guys whose process of discovery consisted mostly of “be super smart, and work really hard.” I couldn’t come up with a way to fit him into the framework of the book, other than the notion of back-of-the-envelope estimation. But you can’t do that without bringing math into it, and that would’ve pushed the book into a different category…)