Sunday, May 22, 2005

GRENDEL'S LAUNDRY LIST: READINGS FROM TOM STOPPARD'S HAPGOOD Mathematics does not take pictures of the world, it's only a way of making sense. Twins, waves, black holes - we make bets on what makes best sense.   Niels Bohr lived in a house with a horseshoe on the wall. When people cried, for God's sake Niels, surely you don't believe a horseshoe brings you luck!, he said, no, of course not, but I'm told it works even if you don't believe it.   Look at the edge of the shadow. It is straight like the edge of the wall that makes it. This means light is particles: little bullets. Bullets go straight. They cannot bend round the wall and hit you. If light was waves it would bend round the wall a little, like water bends round a stone in the river.   When you shine light through a gap in the wall, it's particles. Unfortunately, when you shine the light through two little gaps, side by side, you don't get particle pattern like for bullets, you get wave pattern like for water. The two beams of light mix together and –   I'm telling you but you're not listening. Now we come to the exciting part. We will watch the bullets to see how they make waves. This is not difficult, the apparatus is simple. So we look carefully and we see the bullets, one at a time. Some go through one gap and some go through the other gap. No problem. Now we come to my favourite bit. The wave pattern has disappeared. It has become particle pattern again.   Because we looked. Every time we don't look, we get wave pattern. Every time we look to see how we get wave pattern we get particle pattern. The act of observing determines what's what.   How? Nobody knows. Somehow light is continuous and also discontinuous. The experimenter makes the choice. You get what you interrogate for.   An electron can be here or there at the same moment. You can choose. It can go from here to there without going in between; it can pass through two doors at the same time, or from one door to another by a path which is there for all to see until someone looks, and then the act of looking has made it take a different path. Its movements cannot be anticipated because it has no reasons. It defeats surveillance because when you know what it's doing you can't be certain where it is, and when you know where it is you can't be certain what it's doing: Heisenberg's uncertainty principle; and this is not because you're not looking carefully enough, it is because there is no such thing as an electron with a definite position and a definite momentum; you fix one, you lose the other, and it's all done without tricks, it's the real world, it is awake.   ...when things get very small they get truly crazy, and you don't know how small things can be, you think you know but you don't know. I could put an atom into your hand for every second since the world began and you would have to squint to see the dot of atoms in your palm. So now make a fist, and if your fist is as big as the nucleus of one atom then the atom is as big as St Paul's, and if it happens to be a hydrogen atom then it has a single electron flitting about like a moth in the empty cathedral, now by the dome, now by the altar . . . Every atom is a cathedral. I cannot stand the pictures of atoms they put in schoolbooks, like a little solar system: Bohr's atom. Forget it. You can't make a picture of what Bohr proposed, an electron does not go round like a planet, it is like a moth which was there a moment ago, it gains or loses a quantum of energy and it jumps, and at the moment of quantum jump it is like two moths, one to be here and one to stop being there; an electron is like twins, each one unique, a unique twin.   Its own alibi.   It upset Einstein very much, you know, all that damned uncertainty, it spoiled his idea of God, which I tell you frankly is the only idea of Einstein's I never understood. He couldn't believe in a God who threw dice. He should have come to me, I would have told him, 'Listen, Albert, He threw you - look around, He never stops.'   There is a straight ladder from the atom to the grain of sand, and the only real mystery in physics is the missing rung. Below it, particle physics; above it, classical physics; but in between, metaphysics. All the mystery in life turns out to be this same mystery, the join between things which are distinct and yet continuous, body and mind, free will and causality, living cells and life itself; the moment before the foetus. Who needed God when everything worked like billiard balls? What were you going to say?   1:50:57 PM    comment []