- #1
entropy1
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Suppose we have a double slit and we fire a photon through it with no photon detector at either slit. We get a interference pattern.
Now we put a photon detector at the left slit. The interference pattern is destroyed, right?
In this last setup, the photon can be located at the left slit. So if the photon went through the left slit, it was detected and the interference is gone. My question is: if the photon went through the right slit, it wasn't detected because we haven't got a detector at the right slit. So how did the photon know it had to go through one of the slits (the right one) if it was never detected, unless it was a wave from the beginning?
Now we put a photon detector at the left slit. The interference pattern is destroyed, right?
In this last setup, the photon can be located at the left slit. So if the photon went through the left slit, it was detected and the interference is gone. My question is: if the photon went through the right slit, it wasn't detected because we haven't got a detector at the right slit. So how did the photon know it had to go through one of the slits (the right one) if it was never detected, unless it was a wave from the beginning?