NSA’s quantum ambitions revealed in Snowden documents

The NSA is trying to build a quantum computer in order to break today’s digital encryption and create new types of encryption, the Washington Post has used documents leaked by Edward Snowden to reveal. Quantum computers can theoretically compute much faster than today’s “classical” bit-based systems, which would help them break encryption by brute force, a.k.a. high-speed guesswork – most encryption today relies on the fact that cracking it by brute force would take unfeasibly long. However, though some firms such as D-Wave claim to have built small-scale, early-stage versions, no-one has managed to build a large-scale quantum computer yet.