It's no coincidence that, in the lobby of ones its buildings, the Center has a poster of Einstein on a bike. Einstein is often quoted as saying he got his best ideas on a bicycle. (Although if Einstein actually said all the things he is supposed to have said he must have been more talkative than most human beings.)

Officially, I was in Aspen to think about the Big Bang, but while I was there I also found myself mulling over the physics of cycling. Not the physics of why bikes stay up (although that is complex and certainly interesting), but how physics lets bikes be so good at what they do.