Most people probably couldn't tell you what quantum computing is. And, as we learned last week from an unusual public spat between tech companies, it turns out that the top quantum computing engineers aren't so sure either.
It all started when Google researchers published a paper in the journal Nature declaring that they achieved "quantum supremacy" – a breakthrough in computing speed so radical that, to use a fictional analogy, it might be akin to attaining hyperspace travel speed.
But before the champagne had even been poured, IBM was disputing Google's claims with a blog post, insisting that technically, "quantum supremacy" hadn't really been reached.
Quantum computers have special properties that allow them to solve problems exponentially faster than even the most powerful computers today. Google researchers say their quantum computer solved a problem in 200 seconds that would take a powerful supercomputer 10,000 years to solve — a potential game-changer for fighting climate change, discovering drugs, predicting the stock market, and cracking the toughest encryption.
Quantum computing is still in its infant stages, and you won't find them in your office anytime soon, but investors and researchers see huge potential in them. Already, companies like Google, IBM, Microsoft, and Intel are racing to build quantum computers, while VC's are pouring money into startups like IonQ, Rigetti Computing, Aliro, and D-Wave.
The feud between IBM and Google is in many ways academic. But it also highlights the prominence and importance within the industry of a technology considered science-fiction just a decade ago. As current computing technology gets pushed to its limits, new technology like quantum computing has the potential to open entirely new markets and to shake up the balance of powers in the tech industry.
And while Google and IBM are taking different approaches to quantum, the rival claims underscore the seriousness with which each company views the technology.
"Google is doing things as a research project," Brian Hopkins, vice president and principal analyst at Forrester, told Business Insider. "IBM has a commercial strategy, pouring money in to get money out. They want to get to a point where quantum computers are powerful enough so people are willing to pay money to solve problems.
At the same time, rivals like Microsoft, Intel, and quantum computing startups are lauding Google's experiment and see it as a good sign for quantum computing.
"We're beginning to have a discussion that a quantum computer can do something that a supercomputer does not," Jim Clarke, director of quantum hardware at Intel, told Business Insider. "It motivates us that we're on the right path. There's still a long way to go to get to a useful quantum computer. I think this is a positive step along the way."
'The record holder in the 3-yard sprint'
Computer experts that Business Insider spoke to say it will take time to prove whether Google did in fact reach this benchmark and whether IBM's disputes are correct.
IBM, which built Summit, the world's most powerful supercomputer, says the experiment can be run by a supercomputer in 2.5 days, as opposed to the 10,000 years Google said would be required with a traditional computing technology.
In other words, even though Google's quantum computer is faster, if it's true that the supercomputer can run that same problem in 2.5 days, it's not that large of a difference. Running a problem that takes 10,000 years to solve is impractical, but if it takes 2.5 days to solve, it's not that big of a deal.
"The conflict between Google and IBM highlights that there's some ambiguity in the definition of quantum supremacy," Bill Fefferman, assistant professor of computer science at the University of Chicago, told Business Insider.
Still, Google's work shows the progress of quantum computing, and people shouldn't lose sight of that, despite the arguments about it, says Martin Reynolds, distinguished vice president at Gartner.
That being said, since quantum computing is still in its early days, Google's milestone is "a bit like being the record holder in the 3-yard sprint," Reynolds says.
Fefferman adds that the "jury is still out" on whether Google has actually reached quantum supremacy, but not because of anything IBM said.
"While it's not completely clear to me that there's currently enough evidence to conclude that we've reached quantum supremacy, Google is certainly breaking new ground and going places people have not gone before," Fefferman said.
And although Google's experiment is a "major scientific breakthrough," it has little impact on commercial users today, says Matthew Brisse, research vice president at Gartner.
"It demonstrates progress in the quantum community, but from an end user perspective, it doesn't change anyone's plans or anyone's project initiatives because we're still many years away," Brisse told Business Insider. "We're literally five to ten years away from using this in a commercial production environment."
A 'landmark scientific achievement'
In general, IBM and Google's competitors told Business Insider they see the experiment as a step forward.
"This is an exciting scientific achievement for the quantum industry and another step on a long journey towards a scalable, viable quantum future," a Microsoft spokesperson said in a statement.
Chad Rigetti, founder and CEO of the startup Rigetti Quantum Computing, calls Google's experiment a "remarkable achievement" and should give researchers, policymakers, investors, and other users more confidence in quantum computing.
He adds that IBM's claims hasn't been tested on actual hardware yet, and even if it was proved, it would still be slower and more expensive to run than on Google's quantum computer.
"The Google experiment is a landmark scientific achievement and the most important milestone to date in quantum computing," Rigetti told Business Insider. "It shows that real commercial applications are now within sight for superconducting qubit systems."
Clarke, of Intel, agrees that it's a positive for the quantum community overall, although he notes that calling it "quantum supremacy" might be debatable. Clarke also says that it could show that quantum computers can be more efficient, as he suspects that Google's quantum computer uses much less power than running a Summit supercomputer for over two days.
"What's been interesting to me is seeing some of the negative reactions to this announcement," Clarke told Business Insider. "If you're in the quantum community, any good experiment that suggests there's a long future in quantum computing should be appreciated. I haven't quite understood some of the negative response at this point."
'We're not as far away as we were thinking 10 years ago'
What happens next is that other scientists will review the paper, work to prove or disprove it, and debate whether quantum supremacy has been reached. Ines Montaño, associate professor in applied physics at Northern Arizona University, says that IBM will likely work to prove that its supercomputer can run that experiment in a shorter time frame.
"IBM will have to figure out something to put some data to their claim," Montaño told Business Insider. "That will be a very public discussion for a while. In the meantime, there's the quest is to find problems that may be more applicable to current things...We're not as far away as we were thinking 10 years ago."
This will likely take some time as quantum supremacy is difficult to prove. Still, quantum computing is still in its early stages, experts say, and they expect more advancements in the coming years. Experts predict that the industry is still at least 10 years away from useful quantum computers.
"Google's managed to find a complex problem that they can solve on this system," Reynolds told Business Insider. "It isn't a useful solution, but it is a big step forwards. IBM offers a way to solve the problem with classical hardware in a couple of days. That's also impressive, and shows the caliber of thinking that we find in these early quantum programs."