Comments by "kazedcat" (@kazedcat) on "Extra History" channel.

@isodoublet There is a way by measuring where the photon is not. By constructing your experiment in a way where your photon detector is in a location with very low probability of actually detecting a photon. You then build up an understanding of where the photon is by bounding where it is not. I remember there was a hot debate over whether you are actually measuring things because you are using quantum mechanics to guide you where to place the detector so that it will not detect photons. But non detection is also a measurement you know precisely that the photon is not there.
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