Liquid light sounds like a contradiction, since the three phases – gas, liquid and solid – usually only apply to atomic matter. Although researchers sometimes talk about a light beam as if it’s a gas, because the photons move around randomly within the beam and can exert pressure due to their momentum, they don’t usually mean it literally – until now.

Light can be turned into a glowing stream of liquid that splits into droplets and splatters off surfaces just like water. The researchers who’ve worked out how to do this say “liquid light” would be the ideal lifeblood for optical computing, where chips send light around optical “circuits” to process data.