Superconductivity and the Chess Analogy

Superconductivity is the phenomenon wherein certain metals, when cooled to near absolute zero (-273˚C), are able to conduct electricity with no electrical resistance. In Tales from the Quantum, Art Hobson explains how it works:
  • At normal temperatures, each electron in the metal creates an electromagnetic (EM) field. The carrier for this EM field is a photon, which being massless, extends to infinity;
  • As electricity tries to move through the metal, it experiences this EM field, and that is what we call “resistance” in our daily lingo;
  • Remember how ice and water (or water and steam) are so very different even though they are chemically identical? Such radical changes in properties is called “phase change”;
  • At near absolute zero temperature, the electrons pair up, and the character of the paired electrons is “radically different from normal unpaired electrons”. A phase change has happened;
  • This transformed field of the paired electrons “causes photons to behave in a surprising manner”:
  • “In this new field) Photons acquire inertia – mass – and move at less than light speed.”
  • And any “with mass” carrier particle like a photon, by definition, can only operate over short distances, not till infinity. Ergo, the EM field now operates only over very short distances, “so short ranged that the electron pairs can move through the metal freely, without experiencing usual EM forces”, aka without facing any electrical resistance. Ta da! We have superconductivity.

This explanation is so fascinating because it breaks the “rules”: photons can acquire mass. EM fields become short ranged. But only under certain conditions.

It reminded me of Richard Feynman’s chess analogy for how we try to learn the rules of nature:
“One way that's kind of a fun analogy to try to get some idea of what we're doing here to try to understand nature is to imagine that the gods are playing some great game like chess. Let's say a chess game. And you don't know the rules of the game, but you're allowed to look at the board from time to time, in a little corner, perhaps. And from these observations, you try to figure out what the rules are of the game, what [are] the rules of the pieces moving.
…
Everything's going good, you've got all the laws, it looks very good--and then all of a sudden some strange phenomenon occurs in some corner, so you begin to investigate that, to look for it. It's castling--something you didn't expect.
…
We can have revolutions in physics. After you've noticed that the bishops maintain their color and that they go along on the diagonals and so on, for such a long time, and everybody knows that that's true; then you suddenly discover one day in some chess game that the bishop doesn't maintain its color, it changes its color. Only later do you discover the new possibility that the bishop is captured and that a pawn went all the way down to the queen's end to produce a new bishop. That could happen, but you didn't know it.”
All of which is summarized by Feynman as follows:
“It's very analogous to the way our laws are. They sometimes look positive, they keep on working, and all of a sudden, some little gimmick shows that they're wrong--and then we have to investigate the conditions under which this bishop changed color... happened... and so on... And gradually we learn the new rule that explains it more deeply.”

Call science what you like, but it sure is not boring.

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