Double slit experiment with electron one at a time I understand how a wave create the interference pattern, but what is the mechanism for a single electron after it pass the slit and scatter and land at different location on the screen to produce the same interference pattern.
Does the electron pass through one slit or it split into two before the slit and pass through both the slit? 
Thanks.
 A: Nobody can say what 'really' happens. However, quantum theory says that the wave function associated with the electron passes through both slits and interferes with itself, producing areas of higher and lower probability for the electron to be detected. Whether the electron itself is wavelike, and passes through both slits before collapsing to a point at the detector, or whether the electron is guided through one or other slit by the wave function is still a matter of debate about which interpretation of quantum theory applies.
A: The electron doesn't really interfere with it self but it act as if it does so by avoiding regions with destructive interference and hitting the screen where it should when it would constructively interfere with its hypothetical self coming from the other slit, thus, there is a higher probability of it hitting the screen on a bright region consistent with a constructive interference of  an interference patern than it hiting it on a dark region of that pattern and this means that every single electron that passes through the slits will hit the screen and it will not disappear (in the case of a complete destructive interference ) instead it avoids angeles of destructive interference ..... 
A: All matter has both wave and particle properties, for small particles it is possible to observe the wave properties.  For massive particles it is impossible to observe the wave properties, the theoretical wavelength is too short.  The reason particles have wave properties is because all matter interacts with each other thru the EM field, i.e when a particle is colliding with another the electrons are the first to "see" or "sense" each other (there is something called virtual photons). Because the interaction is in the EM it has to have a wavelength/wavefunction associated with it.  The term interference is historical, the slit experiment for photons showed a pattern similar to what water waves do. Even single photons "interfere" but it is better to think of an allowed path explanation (Feynman) where the brights spots occur. The electron will choose one slit at random, with this new path it will look to interact with the screen at a point that works with its wave function, this causes the INTENSITY pattern (note: I did not want to use the word "interference"!):
