Don't tell the spooks

Scientists in Germany have provided what they call “compelling evidence” that quantum computing will outperform classical computing, even though we can’t build a quantum computer with existing technology. Of course, it is only signals intelligence people like GCHQ and the NSA that have the theoretical means to afford a quantum computer, as it promises to crack normal cryptographic codes in a trice. Downtime suspects that scientists keep mentioning code breaking as the killer app for quantum computing precisely because they know they are onto a good thing regards funding. Be that as it may, Michael Bremner of the Leibniz University, Hannover and colleagues have looked at what they call “a very simple class of quantum computations in which the outcome is unaffected by the order in which the computational steps are performed”. So, in the quantum world all roads lead to Rome. Or as Deep Thought figured, the answer is always, in the end, 42. But don’t tell the spooks.