This is my understanding regarding electron waves. What is seen as an electron wave is just the probability distribution of an electron, the electron always remains a particle. In interference and diffraction patterns, we just observe the probability distribution, which is interpreted as the square of a wavefunction.
If the above understanding is correct, then I have the following questions:
In electron interference, the interference patterns do not appear if the electrons are seen [I mean observed with a light source]. Why does this happen? The interaction should just change the wavefunction and some sort of interference pattern should be seen, because it has some probability density associated.
If all particles can be interpreted as waves by probability distributions, then why is light still considered sometimes as an EM wave. [I read in the book by Arthur Beiser that light apparently travels as waves but exhibits particle behaviour when exchanging energy].
Thanks for the help.