At the smallest scales of nature, the rules of the world shift in ways that can feel unsettling and beautiful at the same time. Matter no longer behaves like solid objects moving along clear paths.

A cluster of 7,000 sodium atoms has just been coaxed into behaving as a single, ghostly wave, stretching quantum weirdness into a realm that starts to look uncomfortably like everyday matter. Instead ...

Photons, for centuries both a puzzle and a tool, continue to help scientists illuminate nature at the smallest and largest scales. Photons, the fundamental particles of the electromagnetic field that ...