Nvidia CEO Jensen Huang apologizes for his quantum effect

SAN JOSE, Calif.—Nvidia CEO Jensen Huang offered a quantum-level climb-down on Thursday, after spooking quantum-computing companies earlier this year with his assessment that their efforts wouldn’t be “very useful” for 15 to 30 years.

Huang’s comments in January triggered a selloff in quantum-computing stocks, with some shares falling 40% or more.

“My first reaction was, ‘I didn’t know they were public! How could a quantum computer company be public?’” he said Thursday, recalling the episode.

Huang explained that his January remarks reflected his experience building computing platforms over a period of decades, and that he was comfortable with such a time frame.

“They can explain why I was wrong,” he said on a panel that included guests from the quantum field as part of Nvidia’s GTC conference.

Huang called the session the “first event in history where a public company CEO invites all of the guests to explain why he was wrong. But that is what makes this movie so great.”

The companies taking part, including PsiQuantum, D-Wave and IonQ, discussed their approaches to quantum, often focusing on the common goal of producing a useful quantum computer that is good at self-correcting errors stemming from the quantum-computing process.

Sorry, not sorry

Even as he delivered a mea culpa, Huang pressed his panelists to think about quantum differently.

“I do wonder whether quantum computing is simply poorly positioned,” Huang said, “because it was described as a quantum computer instead of a quantum instrument.”

He added, “there’s a common sense about what a computer is. It has to have memory, it has to have networks, it has to have storage, it should be able to read and write. There’s a programming model associated with computers. But I wonder if it’s just a wrong mental model.”

Part of the problem, he said, is that quantum computers are being held to the standards of traditional computers when their purpose is actually completely different.

“I think there is an unnecessary expectation, and it actually sets the industry back, frankly, an unnecessary expectation that somehow these forms of computers are going to be better at spreadsheets. It’s an unfortunate expectation; it’s an unnecessary expectation,” Huang said.

Reframing the quantum computer as a scientific instrument could help move the industry along, he maintained.

Not all of the panelists bought the idea.

D-Wave CEO Alan Baratz responded that, while there are many applications he would never try to run on a quantum computer, “I don’t know how to think of a quantum computer as an instrument, when it’s being used for materials discovery, when it’s being used for blockchain.”

“It’s OK. I was actually just trying to help,” Huang responded to laughs.

A great impact in the making

Another risk of invoking the word “computer” is the implication that quantum computers replace traditional computers, which isn’t the case because the two will work together, Huang said. Nvidia faced a similar dilemma early on when it chose to call its technological approach “accelerated computing” rather than “parallel computing,” he added. At the time parallel computing was seen as potentially displacing something called sequential computing. Huang reframed it as “accelerated” to show that the two should actually work together.

“Nvidia accelerated computing is the largest volume parallel computer the world’s ever seen. And yet we don’t call it a parallel computer. For that very reason,” he said. “I think the idea that this is a quantum-computing industry or a quantum computer is less good than a quantum processor that’s going to make every computer better.”

Sequential computing, as the name suggests, means that a computer does one thing after another, whereas in parallel computing, multiple processors take on simultaneous tasks. Nvidia says accelerated computing employs specialized hardware “to dramatically speed up work, using parallel processing that bundles frequently occurring tasks.”

Huang said he hoped quantum technology would make traditional computers better, creating ground truths in domains such as biology, chemistry and physics, which would lead to breakthroughs in drug discovery and materials sciences.

“I think the progress of the industry is incredible,” Huang said. “If I had to be wrong to show quantum computing is going to make a great impact…mission accomplished.”

Huang’s comments didn’t do much for quantum-computing stocks Thursday, with a number of them taking a tumble.

Write to Steven Rosenbush at steven.rosenbush@wsj.com and Isabelle Bousquette at isabelle.bousquette@wsj.com