Monday, July 26, 2004

On the Lighter Side
Measurement. It's such an annoyance. The Metric Maniacs insist that a system invented during the French Revolution is clearly superior to the English system, based, as far as I can determine, on the size of various parts of the human body. Let's see, which is more universal, easier to understand? One ten millionth of the distance between the North Pole and the Equator along the Greenwich meridian or the size of my thumb?
I was watching this documentary about the feasibility (see http://denbeste.nu/) of a manned Mars mission, when I started thinking, OK, so this is it. We're going to the stars. For thirty years it's been really hard to actually believe it was going to happen.

But when we're out on Aldebaran a thousand years from now why should we be using a system of measurement based on a more or less random distance on a third-rate planet in a mediocre solar system in an average galaxy? OK, I've been reading Stephen Hawking, too. So English would be better. If we still have thumbs and feet. But maybe we won't.

So why not adopt a measurement system based on something that won't vary no matter where in the universe we go? I'm talking about light. The speed of light, that is. The light year is used extensively right now. It's neither metric nor English. Its only not universal because of that "year" thing. Why the time it takes for a somewhat average planet - etc. - to go around a mediocre star is relevant will not be apparent to our descendants on Aldebaran. A light year is of course a bit lengthy to be useful for cutting cloth or constructing football fields. But that's where exponents can come in handy. We can use an appropriate fraction of a light year to represent a convenient unit of length. Cloth, lumber or licorice can be measured as a fraction that is universal, at least for observers in a similar frame of reference.