Quantum trick lets you cool objects down using nothing at all

In the strange world of quantum mechanics, nothing isn’t ever actually nothing — and now we have found that nothing, or the absence of a photon, can be used to cool things down.

One of the most common ways scientists cool things down is by using lasers. When particles of light, or photons, with a specific frequency hit an atom or molecule, it absorbs the photon and then fires out another photon with slightly higher energy, which cools the system overall.