Main Question or Discussion Point
I have read that if you set up a double slit experiment and let photons go through one at a time they build up an interference pattern. I have also read that this interference pattern is similar to having a pool with two wave generators on one side of the double slit and looking at the interference pattern on the other side. This "makes sense" to me in some sense as the photon travells as a wave, interferres with itself and the interference pattern is the probality that a photon will be detected. What I don't understand is the fact that you need multiple wave crests to make the interference pattern, how many wave crests does a photon have?