Ooh, my head.... still no result. Did Labour win? No. Did they lose? No. Did the Tories win? Yes. Are they in number 10? No. The markets are going crazy – they and most people like the certainty of a simple yes / no, on / off. Turns out that some elections say ‘yes’ and ‘no’ at the same time.
Reminds me of Quantum Mechanics. No, really. In this microscopic world a particle can both be here and not here at the same time. It can have radioactively decayed or have remained stable at the same moment. Things exist as unresolved possibilities – until we try to observe them, at which point they are forced to be one thing or another. Don’t switch off, there’s a bit about cats later on... but first some sport.
In the week when the World Snooker Championship ended (watching it has been banned in many enlightened countries as constituting cruel and unusual punishment), I thought I’d mention Heisenberg’s Uncertainty Principle. Steve Davis prepares to take a shot (don’t worry, I’ll fast forward) – the cue ball strikes the red and it moves towards the hole. Will it go in or not? The tension is unbearable... how could we tell without having to wait? Well, to decide, we need to know how fast the ball is travelling and in what direction. To discover this, we could fire some light at the ball and detect where it bounces to. The angle of bounce and the time taken for it to reach the detector can be used to work out the speed and direction of the ball. Except it doesn’t. The beam of light is a form of energy. When it hits the ball it exerts a small amount of pressure on it, thus changing its speed and direction – the very things you were trying to measure. Of course, in this case it will be a very small amount that makes little practical difference – it’s Steve Davis, he was going to miss anyway. (sorry Steve). But it does establish a principle – the act of measuring something changes what you were measuring.
Now, where’s the cat... put it in this box with a special little device. (Cat lovers may want to skip to the next paragraph). The device is a radiation detector linked to a gas canister. There is a radioactive particle in the box which has a 50% chance of decaying within a fixed period – say an hour. If the detector is triggered by a decaying particle, the gas is released, thus poisoning the cat. (I said you should have skipped to the next paragraph). Quantum Physics says that at the sub-atomic level, particles (like electrons) behave like waves – with energy, but no specific location. The probability that the particle is actually at some specific place at any time is described by the equation defining the wave. Only when we try to actually observe where it is do we force it to actually be somewhere! Similarly, the probability that the particle has decayed remains just that – a probability, until we force it to be ‘yes’ or ‘no’ by observing it. You may well say that this is both confusing and academic. But the cat certainly wouldn’t. If the particle decays, the cat is dead. If not, it remains alive. Whilst the particle is a probability wave, it is neither and therefore the cat lives. However, the moment we try to observe whether the cat is alive or dead, we force the probability wave to collapse into a definitive ‘yes’ or ‘no’. The act of observing, the act of knowing, forces the particle to ‘decide’ whether it has decayed or not. Checking to see if the cat is alive has a 50% chance of causing its death. Observation can seriously damage your health (or that of a cat).
If the whole universe had been observed already, everything would now behave in a deterministic manner – there would be certainty, everything would behave as a ‘proper’ particle with no ambiguity. But we know that there are countless quantum states in the universe - it is filled with this uncertainty. Which means that it is as yet unobserved, as yet undetermined. At the very least, God has created a universe filled with possibilities. He has created it in such a way that as he observes it, such observation does not interfere with the possibilities. His interactions do not collapse possibilities, He has built openness into the very fabric of the universe. Love does not insist on its own way.
Of course that doesn’t mean that He has no plan, no knowledge, or no means of achieving His goals. It does mean that these are not accomplished in a deterministic framework in which we are simply pawns in a cosmos of certainty.
No cats were harmed in the production of this blog.
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