January 14, 2011
So the other day I was trying to brew a pot of coffee and couldn’t figure out how many ounces were in a tablespoon. Or maybe it was how many tablespoons are in a cup. Or maybe it was how many cups are in a pint. Or maybe it was that a pint’s a pound the world around, except in Britain where it’s twenty ounces, and I still didn’t know how many scoops of water per cup of coffee to add. In the end I just put some water and some coffee in the coffee maker and ended up with something that, while it wasn’t very good coffee, turned out to be an excellent paint remover. I know most Americans wouldn’t touch the metric system with a 3.048 meter pole, but I’ve never been able to figure out why. At least not until recently when I read about the state of the kilogram. I didn’t realize there was an original kilogram, which is made of platinum and iridium and probably some yttrium, just for fun. When I took high school chemistry, back when there were only fifty-three known elements, the teacher assigned us to pick an element and do a report on it. I picked yttrium because, according to my parents’ badly out-of-date Encyclopedia Britannica, yttrium had no commercial uses whatsoever. This was long before the internet, which I can now use to find that yttrium is used to make artificial garnets, which is great fun at parties, and also to see some hot lanthanoid action.
Anyway, the original kilogram is kept under glass and it’s rarely handled by human hands because scientists try to keep their equipment so precisely calibrated that brushing off even a few atoms, or adding the weight of a fingerprint, could completely throw everything into chaos. And that could happen anyway because, in spite of the best efforts of scientists, the kilogram is shrinking. I’m honestly not sure what the problem is, though, because weight is relative, and we probably would know that weight was relative even if it weren’t for Einstein’s theory of relativity, since his theory mostly involves time. In fact Einstein came up with his theory because he noticed how, whenever his relatives came to visit, three days seemed like forever, but that’s another story. Send an astronaut into space and he or she will be completely weightless, which makes space a very popular destination after the holidays when people are trying to shed those holiday pounds. I’d like to think astronauts occasionally ask each other, "How much weight have you lost?" just so they can answer, "All of it!" A kilogram on Earth is going to be heavier than a kilogram on Mars, but lighter than a kilogram on Jupiter, although the big problem with Jupiter is there’s really no place to set anything down. But even here on Earth if the loss of a few atoms could change the kilogram scientists may have to accept that the kilogram ultimately isn’t going to be fixed, although it’ll still be more precise than the pint. Weight, like time, is going to be relative, but at least distance will stay fixed, even though the distance to the bus stop is always going to seem longer when you’re two blocks away and you can see that the bus is stopped at a red light that could change at any second. That makes me think that distance might not be fixed either, in spite of the best efforts of scientists to first define the meter as one ten-millionth of a line of longitude, then a bar of platinum and iridium and some yttrium thrown in for old times’ sake, and finally a wavelength generated by radiation from an isotope of krypton, which is why Superman has never adopted the metric system.
All this reminds me of my college philosophy class where I learned about Zeno’s paradoxes, which talked about how nothing can really move from one point to another because you can divide the distance in half and then you can divide that half in half, and then divide that half in half, and on and on, with each half being infinitely halvable. Among other things this proves that Zeno didn’t understand quantum physics, which makes him just like a lot of quantum physicists. I pointed out to my professor that the distance being halved was the distance travelled, so Zeno was trying to make a finite distance infinite. My professor thought about this and gave me an ‘A’ for being so clever, and an ‘F’ for thinking of something that had never occurred to him in thirty years of teaching. This left me with a ‘C’ average in philosophy, which is one of many reasons I never went on to a career as a standup philosopher.