In my espionage thrillers I’ve touched on quantum computing as if it was a reality. On the other side of the ‘war’ is quantum cryptography. The two communicants (that sounds church-like) in cryptography are usually referred to as Bob and Alice. Currently the RSA cipher is most commonly used and depends on large prime numbers and cannot be broken within the life of the universe. However, quantum computing might threaten this, and so the race is on to develop quantum cryptography.
I’ve written a lot about China and the threat it poses in my novels and this has yet again been demonstrated this week by the announcement that China has demonstrated quantum entanglement over a distance of 1200 km. That brings practical quantum cryptography ever nearer. Why? Because a satellite can be used for quantum key distribution. In fact China has launched a satellite specifically for this purpose. I wrote about it here
You can read the full story at Physics World.
