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Some quantum erasure experiments involve polarization of photons. In one such experiment with a double slit, a horizontal polarizer is used in front of one slit, and a vertical polarizer is used for the second slit and the idea is that then horizontal or vertical polarization of the photon coming out of the double slit "marks" which path it took and so interference pattern disappears. Then the experimenter goes on to erase that which-path information in some way to restore interference. So it seems to me that a photon detector by itself does not work as an eraser and that a horizontally polarized photon entering a photon detector leaves something very different in the detector or the environment than a vertically polarized photon entering the same detector. How is it that a detector that usually cannot tell apart different incoming directions of photons can somehow tell apart different polarization?

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