Not Even Not Zen 449: Biomythography - Note 153, The Plate Dancers

The Plate Dancers

In the Hampshire College library, late at night on an upper floor, I found it. My memory of the moment is so dim, I'm not sure if I simply thumbed through my notebook to find a copy that I had been given previously or if I located the original article somewhere in the journal archives. In either case, I started reading. And I understood it was going to be as good as one of my classmates described it to me when he enthusiastically endorsed the multi-page feature in Science magazine.

The piece told a story about our physics professor, Herb Bernstein - or rather, it described his solution. He and a partner had worked out a valid model for an integer spin value of a neutron. They had based their work on an inspiration Herb had while watching African plate dancers. During a recital at his university, the dancers had balanced a stack of plates in one hand, twisted their wrist to turn the plates 360 degrees counterclockwise and then, instead of turning back, they had kept turning the plates counterclockwise again.

They made a complicated motion to do it. However, it wasn't so complicated that Herb couldn't duplicate the motion while he was sitting in the audience. Years later, at Hampshire College, Herb repeated his dance move for us in his quantum physics class.

"See?" he turned his arm and wrist. Then he twisted again. "Look!" 

After the first move, the dancer's arm is out of position. After the second, both the stack of plates and the hand holding them return to the start. It takes two turns for a dancer to come back to the original position. The move looks beautiful, even when done by an amateur.

When Herb first saw the performance, the dancers had made the moves seem natural. Their arms flowed like water. Plates rose and fell in a hypnotic pattern. Of course, Herb found that he couldn't balance things on the plates the way the professionals could but, as he imitated them, he realized that two spins could indeed return to the same place. For a physics student, it was an important realization.

The spin value of a neutron had been defined as a fraction. Apparently, that bothered some theorists at the time. Herb realized the spin value could also be two, a whole number. He was pretty sure the math would work. The formal announcement of his full-blown theoretical model was hailed as a success. 

Looking back on it, though, the theory never became mainstream. The math seemed to work but the experimental verification of the model somehow never panned out. The spin value of a neutron is still accepted as 1/2, which makes it a type of fermion. At the time, the wonderfulness of Hampshire College, a place where I could hear about why neutrons have a spin value and how it can make intuitive sense - even though it doesn't have to - made me love the promise of the place. I read the physics story with a joy I had usually associated with science fiction.

The college library was a cozy place to study. The friendliness of the Hampshire classes, the ability to design our own coursework, and the closeness we could have with professors all added up to my re-discovering a love for learning - or maybe I was discovering it, really exploring it, for the first time. Pursuing my interests was a powerful sensation. The idea that I could learn something for the pleasure of it and not be measured by anyone was a liberating one. So was the concept that I could self-teach or direct my own intellectual explorations.

For me, an era of passively accepting what someone decided I should learn was coming to an end, although I didn't know it. I was starting to realize I could participate in the decision, at least. I could push back against a nonsensical requirement. I could reach out and choose to learn something that only I felt was related to what I needed to know. 
 
It was a daunting idea for the lazy me. When you explore an area on your own, well, you're on your own. There's no one to help you, no one to make the material easier. There's no one to figure out how one field of discourse applies to another, no one to say that boolean logic can apply to electricity, or that botanical details apply to poetry, or that a plate dancer's arm movement can apply to particle physics. Sometimes, that has to be you.