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BBC 1964: Feynman in Strangeness Minus Three

Steven Miller has sent me a cute 41-minute video:

Richard Feynman, in the BBC Horizon 1964 program called "Strangeness Minus Three", discusses the coming revolution in the understanding of nuclear physics.

Murray Gell-Mann and Yuval Ne'eman predicted a "strangeness=3" particle which had just been found; the quark picture was clearly useful for them. Feynman predicts some breakthroughs in our understanding of nuclear physics. QCD came a few years later.

Feynman discusses the SU(2) symmetry between protons and neutrons and many other features of nuclear physics that had been freshly known to exist at that time. He kindly credits Gell-Mann with the development of strangeness, a numerical quantification of the difficulty that a nuclear particle may have when it wants to decay to a neutron or a proton.

By watching this program, you would never agree that Feynman wasn't nice to Gell-Mann (and others). For example, he says that the search for the Omega minus particle (s=-3) was a typical example of a dramatic scientific investigation. Two ingenious men, Gell-Mann and Ne'eman, had to wait for two years to see whether Nature recognizes their ingenuity. She did. The particle was found. ;-)

Gell-Mann appears at 15:26. He predicts that he has a few more years to actively live; physicists lose flexibility at some point; he describes fiery discussions with Feynman, and so on. After 19:20, Yuval Ne'eman describes his exotic paths from military to science (via Imperial College). (Israeli soldier) Ne'eman has some lovely things to say about his key collaborator (and devout Muslim) Abdus Salam.

A Brookhaven experimenter who found the Omega minus speaks at 23:20. He had to prepare the experiment. Gell-Mann had a great track record of his predictions so it wasn't a problem. Graphs of the decuplet, mass differences, and decay channels are nicely sketched; it seems clear to me that these "technicalities" would be omitted in a 2011 BBC show which would be filmed for a much more dumbed down audience. Finally, the experimenter shows some cutely visual bubble chamber images of their discovered Omega minus.

At 32:50, we get back to Feynman who is a kind of moderator of the show. He discusses how the scientific understanding develops in waves - using an example of periodic table and atomic physics - and meditates on whether or not partially broken symmetries are beautiful or deep. Great discoveries always require some philosophical surprises. Feynman also emphasizes that our (or his) age was exceptional because those things can't be discovered twice. Lots of cute and deep thought of Feynman about Nature and science.

Quite generally, I was impressed by the speaking abilities of all the physicists on the show. Maybe, and quite likely, they were reading some prepared texts. But maybe it is the right thing to do, anyway. It may have been a bad development that the TV shows began to prefer "authentic (disordered) interviews" with the physicists lately.

At the same moment, while the 1960s are often presented as a period of a bursting frenzy in experimental particle physics, I don't quite see it. For two years, people would be waiting for a mundane bound state of three strange quarks and they would dedicate a special BBC show to this single particle in the decuplet. I am absolutely certain that a possible discovery of the Higgs, or even supersymmetry, would make our era much more striking than the 1960s.

That's why I included a link to Lisa Randall's new book, Knocking on Heaven's Door. I happen to know the content in detail and it's excellent - covering quite some details of philosophy of science, particle physics, effective physics, model building, and the LHC. It will be released in September 2011 and you may pre-order it now.

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