Computational complexity

Computer scientists have been searching for years for a type of problem that a quantum computer can solve but that any possible future classical computer cannot. Now they’ve found one.

The latest in a new series of proofs brings theoretical computer scientists within striking distance of one of the great conjectures of their discipline.

The real-world version of the famous “traveling salesman problem” finally gets a good-enough solution.

The theoretical computer scientist behind the influential Unique Games Conjecture delights in the wonders of New York’s Washington Square Park, where he ponders the impossible.

Just five days after posting a retraction, László Babai announced that he had fixed the error in his landmark graph isomorphism algorithm.

The legendary graph isomorphism problem may be harder than a 2015 result seemed to suggest.

Computer scientists are abuzz over a fast new algorithm for solving one of the central problems in the field.

A theorem for coloring a large class of “perfect” mathematical networks could ease the way for a long-sought general coloring proof.

A major advance in computational complexity reveals deep connections between the classes of problems that computers can — and can’t — possibly do.