The quantum computing era is coming… fast

Processors that use the strangeness of quantum mechanics are reportedly achieving much greater problem-solving speed than standard computers - but what will the effect on security be?

'The world is not only queerer than we suppose," said JBS Haldane. "It is queerer than we can suppose." Haldane was a biologist and something of a polymath (Peter Medawar, himself a Nobel laureate, described him as "the cleverest man I ever knew"), and whenever I read anything about quantum mechanics, it's Haldane's aphorism that comes to mind.

Quantum mechanics is the branch of physics that studies what goes on inside atoms. It is not for the faint-hearted, not least because it teaches you that everything you know about the physical, tactile world is wrong. "Our imagination is stretched to the utmost," the great physicist Richard Feynman wrote, "not, as in fiction, to imagine things which are not really there, but just to comprehend those things which are there." And at the quantum level, the things that apparently are there are seriously weird. For example: subatomic particles can be in two places at the same time - a phenomenon known as "superposition" - and any pair of them can be "entangled" in such a way that they can instantly coordinate their properties, no matter how great the physical distance between them. And the strangest thing of all is that since subatomic particles are the building blocks of matter, quantum physics is ultimately, the physics of everything.