It is just another example of uncertainty. Consider light, which was already mentioned in the beginning of our discussion. It can only be emitted and absorbed in certain units; this is what have suggested the photon-theory.

Yet to describe its propagation one is forced to TALK about waves. (Even if we deal with a single photon!) ACTUALLY, this is true not only for light: it is a general fact regarding every elementary particle. So from the classical point of view, the situation is rather paradoxical: a particle can SOMETIMES behave LIKE a wave. From the point of quantum physics, there is no paradox. The particle is a particle, but its position is uncertain. It can be both here and little BIT also there, so actually even a single particle can produce interference phenomena.

It is just another example of uncertainty. Consider light, which was already mentioned in the beginning of our discussion. It can only be emitted and absorbed in certain units; this is what have suggested the photon-theory.

Yet to describe its propagation one is forced to talk about waves. (Even if we deal with a single photon!) Actually, this is true not only for light: it is a general fact regarding every elementary particle. So from the classical point of view, the situation is rather paradoxical: a particle can sometimes behave like a wave. From the point of quantum physics, there is no paradox. The particle is a particle, but its position is uncertain. It can be both here and little bit also there, so actually even a single particle can produce interference phenomena.