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I am doing a project about light interference and am wondering if the classic Two-Slit experiment (where light entering 2 slits comes out of the slits and sets up an interference pattern on the background) can be some how related or tied to quantum mechanics or particle-wave duality? Would really appreciate it and THANKS!

The 2-slit experiment sort of proves that light behaves like a wave, right?

Because particles do not have interference patterns. You can do another experiment that proves that light behaves like particles - but you can even do it in the 2-slit case if you turn the light level way down and have a very sensitive detection system - then it is possible to see the interference patterns even when only 1 photon (light particle) passes through the slit every millisecond or so, and you will see the random bursts from these individual photons in your detector, but on average, after you have waited a long time, the pattern of the places where the photons fall follows the same interference pattern you get in the classical experiment. It is really kind of mysterious, but fascinating.

Arthur Smith

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