Double Slit: Fringes One Photon at a Time
Fire photons one by one, watch single dots grow into interference fringes, peek at the overlapping ripples from the side, and see the pattern vanish when a which-path detector switches on.
Arriving one grain at a time
We fire grains of light (photons) one at a time at a wall with two open gaps. What remains on the screen each time is a single small dot — evidence it arrived as a grain. Nothing strange has begun yet. Just watch, loosely, where the dots land.
Fire one at a time a few times and confirm that each hit is a “dot.”
Fire photons — they always arrive one dot at a time
Δy=λL/d=1.73
Screen Record
Hits0 shots
Fringe spacing Δy1.73