A century ago, the strange behavior of atoms and elementary particles led physicists to formulate a new theory of nature. That theory, quantum mechanics, found immediate success, proving its worth ...

Quantum computers still can’t do much. Almost every time researchers have found something the high-tech machines should one day excel at, a classical algorithm comes along that can do it just as well ...

It may be a decade or more before quantum computers become common enough that we’ll find out whether “post-quantum cryptography” will stand up to genuine quantum computers. In the meantime, some ...