Wednesday, December 28, 2005

Coming to Terms With Probability

Brian Greene has messed up my cozy conception of the world. The Fabric of the Cosmos has taken me through a history of physics from Newton to Einstein and I've kept up fairly well. Greene has now turned to the quantum and at first I was doing fine, the ideas of probability and observation exerting an influence (if a tree falls in the forest...) are not entirely new to me. I don't quite get how particles can act like waves or waves like particles and probability waves make me scratch my head, but I'm still chugging along, enjoying the weirdness. But then I come upon this:

The problem lies in reconciling the macroscopic experience of day-to-day life with the microscopic reality revealed by quantum mechanics. We are used to living in a world that, while admittedly subject to the vagaries of economic or political happenstance, appears stable and reliable at least as far as its physical properties are concerned. You do not worry that the atomic constituents of the air you are now breathing will suddenly disband, leaving you gasping for breath as they manifest their quantum wavelike character by rematerializing, willy-nilly, on the dark side of the moon.
You know Brian, I hadn't thought about it until you just mentioned the possibility of it. I didn't know it was possible. But now you have told it to someone with a rather active imagination, and while you try and reassure me in the next sentence that I shouldn't fret about it because "according to quantum mechanics the probability of its happening, while not zero, is absurdly small," this is no comfort Brian. The fact that the possibility is not zero means that it could happen and we all know that even when the odds are in our favor we can still lose. So, while I had never thought about the air having a quantum moment and rematerializing on the dark side of the moon (Pink Floyd tried to warn me, but I just thought they were groovy tunes!), I'm thinking about it now. I am either going to have to start stockpiling oxygen or look into purchasing lunar real estate. Or both. So thanks Brian. Thanks a whole heck of a lot.