“Surely You’re Joking, Mr. Feynman”: Adventures of a Curious Character

A good example of this was an experiment by Valentine Telegdi, in which he measured the number of electrons that go out in each direction when a neutron disintegrates. Our theory had predicted that the number should be the same in all directions, whereas Telegdi found that 11 percent more came out in one direction than the others. Telegdi was an excellent experimenter, and very careful. And once, when he was giving a talk somewhere, he referred to our theory and said, “The trouble with theorists is, they never pay attention to the experiments!”

Telegdi also sent us a letter, which wasn’t exactly scathing, but nevertheless showed he was convinced that our theory was wrong. At the end he wrote, “The F-C (Feynman—Gell-Mann) theory of beta decay is no F-C.”

Murray says, “What should we do about this? You know, Telegdi’s pretty good.”

I say, “We just wait.”

Two days later there’s another letter from Telegdi. He’s a complete convert. He found out from our theory that he had disregarded the possibility that the proton recoiling from the neutron is not the same in all directions. He had assumed it was the same. By putting in corrections that our theory predicted instead of the ones he had been using, the results straightened out and were in complete agreement.

I knew that Telegdi was excellent, and it would be hard to go upstream against him. But I was convinced by that time that something must be wrong with his experiment, and that he would find it—he’s much better at finding it than we would he. That’s why I said we shouldn’t try to figure it out but just wait.

I went to Professor Bacher and told him about our success, and he said, “Yes, you come out and say that the neutron-proton coupling is V instead of T. Everybody used to think it was T. Where is the fundamental experiment that says it’s T? Why don’t you look at the early experiments and find out what was wrong with them?”

I went out and found the original article on the experiment that said the neutron-proton coupling is T, and I was shocked by something. I remembered reading that article once before (back in the days when I read every article in the PhysicalReview–it was small enough). And I remembered, when I saw this article again, looking at that curve and thinking, “That doesn’t prove anything!”

You see, it depended on one or two points at the very edge of the range of the data, and there’s a principle that a point on the edge of the range of the data—the last point—isn’t very good, because if it was, they’d have another point further along. And I had realized that the whole idea that neutron-proton coupling is T was based on the last point, which wasn’t very good, and therefore it’s not proved. I remember noticing that!

And when I became interested in beta decay, directly, I read all these reports by the “beta-decay experts,” which said it’s T. I never looked at the original data; I only read those reports, like a dope. Had I been a good physicist, when I thought of the original idea back at the Rochester Conference I would have immediately looked up “how strong do we know it’s T?”—that would have been the sensible thing to do. I would have recognized right away that I had already noticed it wasn’t satisfactorily proved.

Since then I never pay any attention to anything by “experts.” I calculate everything myself. When people said the quark theory was pretty good, I got two Ph. D.s, Finn Ravndal and Mark Kislinger, to go through the wholeworks with me, just so I could check that the thing was really giving results that fit fairly well, and that it was a significantly good theory. I’ll never make that mistake again, reading the experts’ opinions. Of course, you only live one life, and you make all your mistakes, and learn what not to do, and that’s the end of you.

Thirteen Times

One time a science teacher from the local city college came around and asked me if I’d give a talk there. He offered me fifty dollars, but I told him I wasn’t worried about the money. “That’s the city college, right?”

“Yes.”

I thought about how much paperwork I usually had to get involved with when I deal with the government, so I laughed and said, “I’ll be glad to give the talk. There’s only one condition on the whole thing”—I pulled a number out of a hat and continued—”that I don’t have to sign my name more than thirteen times, and that includes the check!”

The guy laughs too. “Thirteen times! No problem.”

So then it starts. First I have to sign something that says I’m loyal to the government, or else I can’t talk in the city college. And I have to sign it double, OK? Then I have to sign some kind of release to the city—I can’t remember what. Pretty soon the numbers are beginning to climb up.