Researchers in the States have found a way of predicting how evanescent light waves might behave. The breakthrough could clear the way for a new generation of nanoscale optical devices, including solar thermal energy technologies. When things get very small, nanoscale small, the rules all change and almost every assumption …
Unknowable in physics terms
Err, if you know where the photon is, you can't know where it is going and if you know where it is going, you can't know where it is... Werner Karl Heisenberg strikes again.
So saying the position is unknowable in physics terms isn't strictly true...
... I'm not certain about that
I've seen the error message: 'Word cannot edit the unknown', which puzzled me for a while, but perhaps it was just thinking about evanescent light waves...
Link + Pics
This seems to be the initial press release (with pretty picture):
Couldn't find the paper on arXiv.
They probably just can't get their kit in the gap. ;)
Actually, there's more to QM than Heisenberg. For example, the position of an electron in a Hydrogen Atom is unknowable, thanks to wave-particle duality and the need for its Energy etc.. to be quantised.
Plus evanescent waves are little buggers. For example, frustrated total internal reflection (which is what is being described in the article) is a form of "tunnelling" that can be modelled classically using Maxwell's equations without QM. And the PR link above claims the photon's *direction* is imaginary, which, if correct, would make it tough to pin them down.