There are a lot of questions about the double slit experiment on this site, none of them answer my question specifically, and there are basically two theories why the dark fringes should be dark:
- every single photon, that is shot one at a time, lands on the bright area, thus, no photon lands in the dark area, that is clearly understandable
All photons passing thru the slits leave a dot on the screen, this is true for single or multiple photon intensities
In principle every photon that passes the double slit should end on the screen.
- photons go everywhere, but energy from the dark fringes returns to the apparatus
It experimentally shows that the light from the dark fringes goes back to the source of the collimated beams.
For so long, I thought that 1. was the true explanation. Somehow I have a hard time reconciling both 1. and 2. together. If every single photon that is shot, leaves a bright spot, then all the energy from the photons is absorbed there, locally. There is no energy going to the dark areas at all. Then what energy is returning to the apparatus?
- Why are the dark fringes dark in the double slit experiment?