Sorry. I'm just wondering what matter waves (e.g. ## \lambda = \frac {h}{p} ##) for an electron for example are classified as. How is an electron's wave inherently different than the wave represented by a photon or other elementary particle besides producing a different diffraction pattern? Do both waves propagate in any particular field (e.g. EM)? I guess I'm just trying to understand what it means for an electron to have a wave but I was under the assumption it also requires some kind of field, too.