is there an upper & lower limit to photon wavelength? could the wavelength of a photon approach the planck scale, its energy will of course continue to go up. will there be a point where it will either spontaneous become a particle or collapse into a black hole? is there a lower limit to the wavelength of a photon? for example, if a photon had a wavelength of one light year, how could one part of the photon move as the other part trails by a light year. does the fact nothing travels faster than light, and the fact some photons have wavelength in picometers, and other photons have wavelengths of several kilometers have any implications about the internal structure of the photon?