In chapter one of the book Why Does E=mc2?, the authors talk about the idea of being able to plot things out on a grid. We can start with the longitude and latitude of the earth, a system which works very well, and extend it out infinitely into space. That, then, can be the box in which things move around. If we do this, then even if everything (planets, airplanes, the solar system, the universe) is moving around, we can still say where they are.

I think this is the image we grew up with, in which we can say that Mars will be visible in the evening sky to the west, just above the horizon, or that the Big Dipper shows us true North and stuff like that. We recognize that we’re moving, but we carry our imaginary grid around with us, and say where things are in relation to ourselves.

Once we give up the idea that “in relation to ourselves” is an adequate position to take, then we have to give up the idea that things really are in a particular place. If there isn’t any unmoving spot at which to anchor the grid, then the grid itself becomes meaningless, and we can no longer say that something occupies a location.

I read an explanation of relativity once that talked about loud music in the park. For people, who can get up and move away easily to a place where the sound is quieter, it makes perfect sense to think of the volume as relative to your location (your location relative to the source of the sound, that is). We have no trouble with the concept of sound that is louder when you’re closer to the source and softer when you move away.

But for a snail, which couldn’t leave the area before the end of the music, it would seem preposterous to talk about loudness being relative.

So I guess that’s why we have to think about outer space before we can grasp the idea of space and motion being relative in any useful way.

And I see a lot of connection between relativity and the fact that today’s carol, “Little Donkey,” was completely unfamiliar to me until I read yesterday that it is one of the top ten Christmas Carols in England.

This totally amazed me.

Not that there was a carol that I hadn’t heard, because after all that’s the whole point of my bringing you carols that might be new to you — there’s so much Christmas music that none of us has to be limited to hearing the same five tunes till we get sick of them.

But I was amazed that there would be a carol that was in the top ten most popular list in a nation that I tend to think of as relatively nearby, and that I would never hear of it. It’s not only that so many of the songs we sing at Christmas are in fact from England in the first place, so you might think I’d be up on the oeuvre. It’s that England is in continual contact with the U.S. and we share so much stuff — except this carol.

I just yesterday finished an assignment for a British musician’s website, the second time this month I’ve worked virtually in England. I’ve read three British novels this month. I read some English people’s blogs. I have a cousin who lives in England, though he’s French rather than British. But still, wouldn’t you think that some time over the years, it would have come up in conversation?

“We’ve been singing ‘Angels from the Realms of Glory’ and ‘Little Donkey’ a lot lately,” someone might say, or “I feel the same way about ‘Little Donkey’ that you do about ‘The Little Drummer Boy.'” Nope.

Here is a karaoke singalong so you can learn this wildly popular carol. You can also download the song  and get a little insight into the theology. A nice little essay on the subject provides quite a testimonial for the carol.  This song was written in the 1950s by Eric Boswell, a composer from the north of England who died this month. He trained, as it happens, as a physicist. After the second world war, he began entering songs into competitions. “Little Donkey” was originally a much more complex song, but a singer named Gracie Fields (if you’re in England, apparently, you have to describe her as “the legendary Gracie Fields”) wanted to record it and didn’t have much of a vocal range, so she persuaded Boswell (then named Simpson) to simplify it.
This was a great idea from a marketing standpoint, as it was then recorded by all sorts of people I’ve never heard of, and is now sung every year at schools all over Britain and is, in fact, one of the most popular carols they have.

I don’t know why the British have been keeping it from us all these years. I plan to go around singing it today, and I hope you will too. I also want your views on relativity and the theological nuances of donkeys. If you want to talk with a bunch of people about relativity and the book Why Does E=mc2, you can do so at SPOB.

I’m giving another final today, and #2 son is coming home. Last night, having spent the day on tech issues of various kinds (screenshots from Wii, broken email templates, file replication, stuff like that), I found myself alone in the house at dinnertime. I took the opportunity to have sauerkraut, in the form of Choucroute Garni, which I like very much, but which no one else in my family will eat.

I then finished knitting #2 son’s sweater. I have to put it together and do the neckband, and I might have it finished and under the tree before he arrives today. It could happen.

Oh — and, having whined about the slowness of payments this month (and with reason), I should also rejoice over the face that two of my small projects have paid me immediately, and paid more than we had agreed on. I assume this shows that they were happy with my work and not Christmas spirit, but it’s still very nice of them.