I read about a double slit experiment where the detector clicks when a photon goes through the slit. When the detector doesn't click, it means the photon must have gone through the other slit, and a particle pattern still forms. I can't find the experiment that's being referred too though. Does anyone know how I can find it?
This was a thought experiment .... it is impossible for a photon to produce a click and then carry on to the screen. If a photon makes a click it is detected and that's the end of the photon. For electrons an actual experiment was done using light to detect which slit ... and this caused the electrons to stop making the pattern.
Also you can read this answer for more insight: How does the double slit experiment ensure phase coherence?