Heisenberg's Uncertain Santa Claus
I love this season, no matter what you call it — Christmas time, the holiday season, yuletide, whatever — it is a very happy time of year. This is an especially significant Christmas for me as it will be my first with a real live Christmas tree!
I know it's shameful that it took so long, but I grew up with an artificial tree and always travel to my parents' in New York for the holidays, so I never bothered to get one myself. However, last Sunday — during a snow storm, no less — I went out with my significant other Danielle and we picked out a nice small 5-foot-tall fir to put up in our apartment.
But I didn't write this column to talk about trees, I wanted to talk about Santa Claus.
Have you ever heard a child wonder aloud how Santa could possibly visit every home in the world in one night? Or perhaps you've wondered that very thing yourself. I know I have, and I came up with an answer.
The standard answer to any scientifically based question about Santa Claus is, "He's magic." Well I don't think that's good enough. When a child has a question about the natural world, telling them it's magic is a cop-out. But saying Santa doesn't exist isn't a good answer either, it closes their minds to amazing amount of weirdness our universe can produce, by telling them the fantastic just isn't real.
So I started thinking about how Santa could make it to all those billions of houses. Immediately I knew what area of science to start with. There is just one theory wacky enough to allow for someone like Santa Claus to exist — quantum mechanics!
If you aren't familiar with quantum mechanics it is, at it's most basic, a branch of physics that explains how very very small things work. And boy is it weird! I'll do my best to explain the concepts that relate to Santa, but first I should let you know I am far from an expert on the subject. To quote the great physicist Richard Feynman, "If you think you understand quantum mechanics, you don't understand quantum mechanics."
One of the central tenants of quantum mechanics is particle-wave duality, which basically means that all matter has properties of both a particle, which has mass, and a wave, which transfers energy.
One of the easiest ways to understand this duality is to think of light. A particle of light is called a photon and can be measured in a science lab, but light also acts like a wave. In the famous "double-slit" experiment, when single photon of light passes through a boundary with two slits, rather than going through one or the other slit only, it appears to go through both, interfering with itself in an unmistakeable wave-like pattern projected on the other side.
So I theorize that Santa has a Claus-wave duality. He exists both as the jolly Father Christmas and a wave that will expand southerly over the globe — allowing him to cover more ground.
This is where the Heisenberg Uncertainty Principle comes in. According to Heisenberg the more accurately you measure one complimentary variable of a particle the less you can know about another. So if we know where Santa's momentum is carrying him we can't know what his actual location is.
So as our Santa-wave leaves the north pole his momentum carries him south, but he spreads out east to west, eventually covering the globe. Now at any point Santa in his particle form could be in any individual position, perhaps in at a child's home in Paris or Cairo or Belfast, Maine. However, because he also acts as a wave he could also be in an entirely different home.
In the Copenhegan interpretation of Quantum Mechanics, when a particle (or in this case, Santa Claus) could exists in one of a number of different states, it will exist in all those states simultaneously until it is measured, or observed. In Erwin Schrodinger's famous thought experiment, a cat, contained in a box, with a 50-50 chance of being killed by poison inside the box will be both alive and dead until someone opens it up and checks.
So Santa is able to exist in every possible location covered by his wave around the globe. Thus, if no one ever sees Mr. Claus, he's able to visit every home at the same time!
The crux of the problem though is in the measurement because if just one child actually sees Santa delivering her a present, he will cease to behave like a wave and exist only in her living room, depriving the rest of the world of gifts. So kids, don't look for Santa. Christmas depends on it!