Question

Particles are launched at a barrier, and half of them get through. When these same particles are fired at a second barrier, once

again only half get through. If the barriers are placed consecutively, the particles that get through the first barrier don’t get

through the second. A reasonable explanation for this is that there are two varieties of these particles, and these barriers are

actually filters that allow only one of the two species of particle to get through. A third barrier is now brought into play, and is

placed between the other two. Amazingly, some non-zero fraction of particles now passes through all three barriers! Discuss

how this might occur from the standpoint of wave-particle duality.

Answer 1

We can think it as light-Polarizer problem.In the first case there were two crossed polarizer.Hence nothing could escape from the second barrier.But now we introduced a third polarizer(barrier) at an angle theta with lets say the first polarizer.Now some part of the light coming out from the middle polarizer will have component along the last polarizer and non zero fraction of particles can go through from all the three barriers.

Hence we can have a possible explanation of this if we consider particles as waves.(wave-particle duality) and simply arguing what light would behave.