Sorry for opening up the discussion again, but I joined late. anantchowdhary's question is an extremely valid one, even though most commentators claimed to not understand the question. A photon has a wavefunction. The standard interpretation is the wavefunction gives the probability that the photon is at a specific location at a specific time. As it travels at c, there is always an area where it can not be (probability is 0). What is the size of the area where it can be? It is also an electromagnetic wave (maybe wavelet or wavicle is a better word). How many cycles of the wave makes the photon? What is its length (in time or in space), and through which hole will it fit? The energy in a single cycle of an EM wave is always the same (Plank's constant) - no matter the frequency. When absorbed or emitted, the energy is transferred to/form motion. Is the energy transferred in the head of the wavefunction, the tail or anywhere in between depending on the probability?