Light as a wave, which wave is the "correct" wave? Okay so when describing light as a wave, I get two different images depending on what Im looking at. So when Im looking Young's double slit experiment I see light as "wave fronts" like in this picture: https://encrypted-tbn1.gstatic.com/...6dzBTVqWtbn_ZUrCEfOHdAv7FIMm7Cyijjlnigq6mkbUw But in the photoelectric effect light is show as this type of wave: http://science.hq.nasa.gov/kids/imagers/ems/roygbiv_waves.gif So when talking about light as a wave, which wave is the "correct" wave? I ask this because the photoelectric effect shows why light isn't a wave but if you use the "wave fronts" light then there doesn't seem to be a problem. My second question. When light is shone through a single slit, you get a maxima in the middle and some other maxima like this: http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/imgpho/sinslitwid.gif How can this be explained using phasor arrows where the photons dont interfere with themselves?