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Physics

Double Slit Experiment

Quick fact

The double-slit experiment was first performed with light by Thomas Young in 1801 and later extended to electrons, showing that even single particles can create interference patterns.

Why this is interesting

Imagine a single particle of light, or photon, passing through two narrow slits in a wall. What happens? Does it go through one slit, like a bullet, or both at once, like water waves?