D-Wave says its chips use quantum mechanics to solve gargantuan problems.
What's the News: Quantum computing is so complex an idea that even experts have a hard time telling whether a computer is actually "quantum." But D-Wave Systems, a startup that's made news and drawn skepticism over the last four years for claiming to have developed a quantum computer, has just made their first sale
, to the defense contractor Lockheed Martin. And recent research shows that despite the suspicions D-Wave has endured, there may be at least something to their claim. How the Heck:
D-Wave calls their device, a 100-square-foot cube named D-Wave One, a "quantum optimizer." That means that (at least in theory) it uses quantum mechanics to do one thing better than traditional computers: consider various different permutations of a problem simultaneously, thus coming up with an answer in a very short time. For problems where looking at all the options is the only way to find a solution, such as some kinds of code breaking, this capability is something of a holy grail.
Lockheed says they plan to use D-Wave One to help solve their difficulties with melding hardware and software in defense technology, which, according to Technology Review, are the reason Lockheed's F-35 strike fighter is more than 20% overbudget.
The usual idea of a quantum computer is a machine that uses superposition--putting bits in more than one state at once--to solve such complex problems. The D-Wave system works along different lines: basically, engineers manipulate the states of quantum bits (qubits) to set up the problem, and if all goes well, the system should evolve into its lowest possible state, which represents the solution (see a great explanation of this at Ars Technica).
The D-Wave One system, pictured here with founder Geordie Rose.
What's the Context:
One reason physicists have been skeptical of D-Wave's claims is that it's not clear that the system is getting to that lowest state quantum mechanically; it could just as well be getting there through thermal fluctuations, which fall under the heading of classical physics. And if that's the case, it's not going to be faster at these kinds of problems than a normal computer.
But in a recent Nature paper, D-Wave researchers reported that at extremely low temperatures, thermal fluctuations can be turned off, making quantum tunneling the only way their system has to get to the lowest state. That's a step in the right direction, but critics have pointed out that further quantum mechanical effects would be required to actually make the computer more efficient than a traditional one, ScienceNOW reports.
The Future Holds: Plenty more work, both theoretical and practical, will be required on the part of D-Wave to convince the physics community that they've got a quantum machine. But this Lockheed sale (to the tune of $10 million for the device and a contract for keeping it running) adds a new twist. Since Lockheed will be undertaking the first serious, commercial use of the system, it will be interesting to see if it will share its experiences with outside scientists. Given the contractor's reputation for secrecy, though, this experiment may remain as much of a black box as D-Wave one itself. Image credit: D-Wave Systems