Light may not seem very interesting in our everyday lives. But to scientists, light’s properties are a constant source of intrigue. The nature of light as both wave and particle, light as the universal speed limit, and the way light interacts with magnetic fields in the atmosphere to form auroras are a just a few examples of light’s fascinating behavior. Recently, researchers from the University of Glasgow and the University of Bristol in the UK have discovered another unusual property of light – or, more accurately, the darkness within light. As the researchers explain, natural light fields are threaded by...