One computer scientist’s “stunning” proof is the first progress in 50 years on one of the most famous questions in computer ...

But then progress stalled, and complexity theorists began to suspect that they’d hit a fundamental barrier. The problem was precisely the universal character of Hopcroft, Paul and Valiant’s simulation ...

A new technique for efficient encoding of LDPC codes based on the known concept of Approximate Lower Triangulation (ALT) is introduced. The greedy permutation algorithm is presented to transform ...