Quantum computers can now solve problems with real-world applications faster than any ordinary computer, suggesting they could be commercially viable, say researchers at quantum computing firm D-Wave. However, outside observers are more cautious.
It had long been hoped that quantum computers will be able to perform some tasks that are impractical or impossible on even the best supercomputers. Google was the first to demonstrate this 鈥�quantum supremacy鈥� in 2019, but only for a somewhat contrived benchmark test with no practical use. Earlier this month, Google launched a $5 million competition to find real-world applications for its machines.
Now, D-Wave says it has achieved just that, claiming its Advantage quantum computer and a prototype Advantage2 machine can calculate transverse field Ising model problems 鈥� a quantum version of a mathematical approximation of how matter behaves when changing state, such as from a liquid to a gas 鈥� that would be impractically difficult to solve on a traditional computer. It calls this milestone 鈥渃omputational supremacy鈥�, a step up from mere quantum supremacy.
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In a paper setting out the work, the team estimates that the world鈥檚 most powerful classical computer, Frontier, would require millions of years to solve these problems and require more electricity than the world produces each year. D-Wave declined 快猫短视频鈥榮 request for an interview and said it couldn鈥檛 comment on the research until it was peer-reviewed. But its CEO, Alan Baratz, : 鈥淭hese problems cannot be solved by classical computers, full stop.鈥�
D-Wave鈥檚 鈥渜uantum annealing鈥� computers differ significantly from machines produced by Google and many others in the industry, and have been criticised as only being able to solve certain classes of optimisation problem, rather than serving as a general quantum computer capable of tackling any problem.
at Lancaster University, UK, prefers to call D-Wave鈥檚 machine a 鈥渟imulator鈥� of a quantum system, but he says it is fair for the company to claim computational supremacy 鈥� within a very narrow scenario.
鈥淚t鈥檚 a very specific task and it鈥檚 not a universal computer or simulator that they demonstrate,鈥� says Pashkin. 鈥淎nd that鈥檚 it, you can鈥檛 use it for anything else.鈥�
While the Ising model problems have obvious applications in physics, a range of optimisation problems that would be useful for the logistics and finance industries can also be represented in a similar way. However, Pashkin says it remains to be seen how many practical problems D-Wave鈥檚 systems can actually compute.
at rival firm Orca Computing says the D-Wave results appear strong and are 鈥渕usic to our ears鈥� because they suggest that so-called noisy intermediate-scale quantum computers 鈥� like D-Wave and Orca make 鈥� can already be useful for certain tasks and therefore are a viable technology.
鈥淚f you can already start making machines that are useful to enterprise and industry, even if they only have quite limited use cases, it changes the commercial proposition,鈥� says Nunn. 鈥淚t pulls in the time horizon for when quantum computing could become profitable, or at least self-sustaining as an industry, rather than just requiring endless amounts of capital.鈥�
But Nunn also warns that both quantum and computational supremacy are milestones with two sides: historically, classical computer scientists have managed to improve algorithms and undermine previously legitimate claims by allowing classical computers to leapfrog quantum computers and move back into the lead.
鈥淧eople will start taking an axe to the results,鈥� says Nunn. 鈥淚n a few months鈥� time, there might be another paper saying: 鈥榃e鈥檝e found a classical algorithm that can do these simulations 10,000 times faster鈥�.鈥�
Meanwhile, Pashkin points to other more concrete hurdles to commercial adoption, such as the machines requiring experienced engineers to keep certain parts supercooled and running properly, and needing physicists to help interpret the results. 鈥淚 think, at the moment, it鈥檚 unlikely鈥� that we will see wide adoption of quantum computers in the near future, he says.
arXiv
