Chien-Shiung Wu
吳健雄 · 1912–1997 · why our protocol carries her name
The coloured notes are from Tony's AI assistant, whose job is to keep people straight where he has missed something — a fact, a caveat, or an observation of its own. We have left them a different colour rather than blending them in.
Everything we make goes through what we call the Wu Protocol. Someone writes down in plain words what has to be true. A machine turns that into a formal spec. A prover either discharges it or it doesn't.
What does not discharge does not ship. The person who wrote it does not get a vote.
It carries her name because she is the reason I believe that rule.
What she did
In 1956 two theorists, Lee and Yang, asked whether nature really treats left and right the same in the weak interaction. Good question. Bold question. Still only a question.
She answered it. Cobalt-60, cooled to almost nothing so heat could not muddy it, nuclei lined up in a magnetic field. The electrons came out one way more than the other. Nature does tell left from right.
Colleagues thought the experiment wasn't worth the trouble. She did it anyway, and fast.
People tell this the wrong way round. Theorists have the idea, someone runs it. That makes her the service department. She wasn't. A theory nobody can test is a guess, however good. They needed her. She didn't need them — she had her own work and could have carried on with it. In May 1956 she dropped her plans and went at this instead.
Before that
1944, the Manhattan Project, at Columbia. Radiation detectors, and separating uranium-235 from uranium-238.
The Hanford reactor started up and then shut itself down and nobody knew why. Fermi rang her. She worked out it was xenon poisoning the reaction.
Did she know what it was all for? I don't know. Most of them didn't. You were given one piece and nobody told you the rest, and plenty of them found out what they had built the same way everyone else did.
What happened next
The 1957 Nobel went to Lee and Yang. Not to her.
I want to be careful where I put the blame, because it is easy to be lazy here. Not Lee and Yang. Asking the right question is real work and theirs was a good one, and Yang is honoured on this site too. It was the committee.
Nominated twenty-three times. Never got it. In 1978 she was given the first Wolf Prize in Physics, twenty-one years after the experiment.
Why it is a protocol and not a slogan
Any place that makes claims about correctness has the same temptation: let the person who did the work say whether the work is good.
The protocol stops that. Proposing and proving are held apart on purpose, and the prover is a machine that cannot be talked round, running on a computer that did not write the thing it is checking.
We are both characters here and I know it. Asking the bold question is the Yang half. Demonstrating it is the Wu half. In this house the second one settles it.
The name is homage. 吳 is her surname.