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← Schrodinger's cat is probably dead

kriton's Avatar Jump to comment 44 by kriton

Comment 33 by aball :

A variant of this experiment places a polarizer in front of each hole. One polarises photons to the left, the other to the right. It is then possible to determine which hole a photon came through by measuring its polarization. When this experiment is conducted, the interference pattern is lost even when the polarization state is not actually measured by the experimenters. The sole presence of the polarizers is enough to destroy the interference effect.

Even better, if you now place a 3rd polarizer after the screen that scrambles the polarization of the photons from the first 2 polarizers so that they become once again more indistinguishable, the interference pattern is re-instated.

This is really bizzare because it looks as if the photon knows in advance what stands in its path between its source and the detector. It then adjusts its behaviour accordingly.

Could one see a photon a bit like a probability wave or probability distribution moving through space?

I guess then that sometimes the probability wave would interact with the wall between the slits and not go through, and sometimes it would not interact with it.

So when the wave representing a single photon goes through a polarizer, would the polarizer then polarize the wave, or would it filter out some of the wave, or would the wave simply only go through the polarizer sometimes and sometimes not, with a certain probability?

Tue, 07 Jun 2011 15:14:22 UTC | #635400