Over a decade ago, when I was first starting to pretend I could write about quantum mechanics, I covered a truly bizarre experiment. One half of a pair of entangled photons was sent through a device ...

The double-slit experiment is the best demonstration of quantum weirdness, in which electrons simultaneously act like particles and waves and seemingly violate basic laws of physics. Now we’re trying ...

Scientists have long known that light can sometimes appear to exit a material before entering it—an effect dismissed as an illusion caused by how waves are distorted by matter. Now, researchers at the ...