This browser could not start WebGL2, so the optical bench can't be drawn. The experiment still runs: use the controls below and read the results in the histogram.
Delayed-choice lab
Entangled photon pairs, one at a time. The signal lands on the screen; its twin is measured later.
False colour: the real light is 702 nm, deep red. The dots' height on the screen is cosmetic; only x is physical.
Delayed-choice lab
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