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# computational complexity

## Latest Articles

### Finally, a Problem That Only Quantum Computers Will Ever Be Able to Solve

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.

### First Big Steps Toward Proving the Unique Games Conjecture

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

### One-Way Salesman Finds Fast Path Home

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

### Subhash Khot, Playing Unique Games in Washington Square Park

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.

### Graph Isomorphism Vanquished — Again

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

### Complexity Theory Problem Strikes Back

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

### Landmark Algorithm Breaks 30-Year Impasse

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

### Theorists Draw Closer to Perfect Coloring

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

### A New Map Traces the Limits of Computation

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