What's up in

computational complexity

Abstractions blog

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
Thinking Places

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.

Illustration: boxing gloves
Abstractions blog

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.

Illustration: boxing glove & graph
Abstractions blog

Complexity Theory Problem Strikes Back

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

Quantum bits, or “qubits,” can be in a superposition of both zero and one.
quantum computing

Computing’s Search for Quantum Questions

Recent tests show that quantum computers made by D-Wave systems should solve some problems faster than ordinary computers. Researchers have begun to map out exactly which queries might benefit from these quantum machines.

Computer Science

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.

Mathematics

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.

Computer Science

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.

2014 Fields Medal and Nevanlinna Prize Winners

A Grand Vision for the Impossible

Subhash Khot’s bold conjecture is helping mathematicians explore the precise limits of computation.