Since the 1990s, evidence has been growing that quantum computers should be able to solve a range of particularly complex ...

If it holds up, it will solve in one fell swoop a number of related problems in pure mathematics, quantum mechanics and a branch of computer science known as complexity theory.

Hypothetical devices that can quickly and accurately answer questions have become a powerful tool in computational complexity theory.

But is there a simpler way? Questions like this one, about the most efficient way to solve problems, are at the heart of the branch of computer science known as computational complexity theory.