A Canadian firm has courted controversy with its claim to have built a practical quantum computer, a feat thought to be decades away. Now, independent teams are trying to understand how the machine works and whether it really can tap the strange world of quantum physics.
For the modest sum of $15m (£9m), a start-up near Vancouver will sell you a black box the size of a garden shed with its logo emblazoned on the side in white neon.
Not sold yet?
What if I told you the contents of the box were around 150 times colder than interstellar space?
You still need some convincing - I get it.
How about this: The box contains a machine that could solve some of the thorniest mathematical problems and revolutionise computing. But there's still disagreement about exactly what it's doing
Geordie Rose
Much of [the scepticism] has gone away as we've continued to advance our technology so far beyond what anyone else has done”
Dr Geordie Rose
Co-founder, D-Wave
If you're still wavering, let me tell you that the company's sales pitch has worked on some big names. Like Nasa, Google, and defence giant Lockheed Martin.
The Canadian start-up in question is called D-Wave and their monolithic machine is - they claim - nothing less than a real, working quantum computer.
Quantum computing exploits the weird physics of quantum mechanics, which takes hold at tiny (atomic or sub-atomic) scales. Computers that tap the quantum realm could carry out complex calculations much faster than their conventional - or classical - counterparts.
While the basic units of information in classical computers are called "bits" and are stored as a string of 1s and 0s, their equivalents in a quantum system - qubits - can be both 1s and 0s at the same time.
This phenomenon would enable multiple calculations to be performed simultaneously. But the qubits need to be synchronised using a quantum effect known as entanglement, which Albert Einstein dubbed "spooky action at a distance".
Scientists have struggled to entangle more than a handful of qubits, and to maintain them in their quantum state. Lab devices suffer from drop-out, or decoherence, where the qubits lose their ambiguity and become straightforward 1s and 0s. This has ensured that quantum computers remain confined to the lab - proofs of principle capable of solving only elementary problems.
Headquartered in the small tech hub of Burnaby, on Canada's west coast, D-Wave has raised upwards of $100m in venture capital from the likes of Amazon founder Jeff Bezos and In-Q-Tel, the venture capital arm of the Central Intelligence Agency (CIA