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Physics

Interferometry

Quick fact

The Laser Interferometer Gravitational-Wave Observatory (LIGO) uses interferometry to detect ripples in spacetime as small as one-thousandth the diameter of a proton.

Why this is interesting

Have you ever noticed the shimmering colors on a soap bubble? That iridescence is a beautiful example of interference—and the same principle allows scientists to measure distances smaller than the width of an atom.