Why do electrons behave like photons in the double slit experiment?
Electrons may behave similarly to photons but they do not behave identically. Textbook descriptions attempt to confuse this issue by attempting to show identity through scaled up defraction photos so that they appear the same. You will find electron microscope defraction photos compared with X-Ray defraction photos (Wichmann, 1967). But if you look closely at the experimental setups (which rarely get mentioned in the textbooks), you cannot substitute an electron for a photon in either a defraction experiment or a double-slit experiment and get the same results. Although experiments with electrons have shown interference effects, the scales of the setup for an electron experiment must occur at magnitudes smaller than setups for light. “This experiment has never been done in just this way. The trouble is that the apparatus would have to be made on an impossibly small scale to show the effects we are interested in.” -Richard Feynman, 1963 We can detect electrons in free space because they
