Roland, make that two. Though this mooshed my head.

I used to really enjoy thinking about how weird QM was. Look! The little photon goes through both holes at the same time! Not really any more though, it's starting to seem a little bit...ordinary.

Which is a good thing, of course.

Quick question - since you can't integrate over a single point, does that preclude the existence of any 'motionless' particle? Anything that ceased to have an appreciable (Planck-length?) amplitude spread would, in effect, not be there? That would chime with the transform duality thingy between location and velocity.

Hope I get chatting to someone who thinks in terms of quantum/classical dualities at some point, purely so that I can use the line "you're very clever, old man, but it's all amplitudes, all the time."