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Physics

The Double-Slit Experiment: Wave-Particle Duality

Quick fact

When physicists first performed the double-slit experiment with electrons in 1961, they found that even single electrons, fired one at a time, gradually built an interference pattern on the detection screen—as if each electron passed through both slits at once.

Why this is interesting

You've probably seen waves in water and particles like sand. But what if a single electron could behave like both? The double-slit experiment reveals nature's most puzzling behavior.