Posts Tagged ‘matrix algebra’

Eigenspace

September 4, 2009

Of all the holiday activities the most pointless has to be collecting pebbles from a mountain stream. Sure, buying a set of devil sticks or a tribal bong is quite pointless, but at least you’re back at home and unpacking them when the inevitable “What the hell I did that for?” moment comes.

Pebbles, on the other hand, take just a couple of minutes to dry and the transformation from Nature’s shiny and vividly coloured piece of art into a dull grey lump of rock takes place right in front of your eyes. (Yes, there could be a subtext here about ageing and how time flies and the lessons we should all learn before it’s too late, but there isn’t. Go for the shape, that’s the lesson. Or reds, they stay red somehow. Even better, keep them in a water tank. Your mates won’t half think you’re daft when they see your water tank with only rocks in it. But nobody will dare ask you about it in case it’s a memorial for the fish you once had but have died since. Anyway, back to the point.)

But the more you think about it, the more you’re convinced that such a perfect lack of purpose or meaning is immensely fascinating. Not only that, it may be fundamental in defining what we are. After all, everybody does things that they gain or at least hope to gain advantage from, but only you can be such an idiot to spend hours and hours fishing out rocks that you know will turn grey or white in a matter of minutes.

Another fine example of creating without regard to result is The On-Line Encyclopedia of Integer Sequences.

2-restricted Stirling numbers of the second kind, primes congruent to 1 mod 12, Ruth-Aaron numbers, numbers of asymmetric permutation rooted trees with n nodes, it’s like a library of Babel for all the integer sequence fans around the world.

Er…that’s it.