Multiplication of two numbers is easy, right? At primary school we learn how to do long multiplication like this: Methods similar to this go back thousands of years, at least to the ancient Sumerians ...

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 ...

Peter Shor didn’t set out to break the internet. But an algorithm he developed in the mid-1990s threatened to do just that. In a landmark paper, Shor showed how a hypothetical computer that exploited ...