Three slits experiments What is the results of three slits experiments ?
What is the difference between it and 2 slits experiments??
How can measure superposition by three slits experiments 
 A: For waves, the diffraction pattern is the Fourier transform of the screen function. What this means it that the wave goes through all slits (1, 2, 3, or more) and make a pattern causes by the various phases adding the way that they add.
When we consider the quantum form of the experiment, the exact same thing happens: the particle takes all possible paths from initial to final state, and the phases add the way they add to produce the pattern. The only difference is that this begs the classical question, "which slit did the particle go through?".
So with 3 slits there are more choices to consider when asking, "which slit does the particle of through?"
The point I want to make is that this is no different from 1 slit, because we can ask the classical question, "Did the particle go through left side or the right side of the slit?". If you don't know, you get a diffraction pattern with width $\theta$, and if you do know, you get a diffraction patter with width $2\theta$. It's basically the 2 slit experiment in the limit of zero separation, which is not a mind boggling as the normal 2 slit set-up, but it's no different:
The particle always takes all possible paths between the initial and final states.
A: I've read that modern experiments use multiple slits. For the three slit experiment the condition for interference is the same as for the 2 slits experiment.
