Google’s announcement on Monday of its new quantum chip, called Willow, was full of eye-catching statements. For starters, Willow took less than a minute to perform a benchmark computation that would take one of today’s fastest supercomputers 10 septillion years to do. That number “exceeds known timescales and physics and vastly exceeds the age of the universe,” says Hartmut Neven, founder and lead at Google Quantum AI, in the announcement.
And then there’s error correction. “We achieved an exponential reduction in the error rate,” Neven says. In fact, the more physical qubits the team added, the more it reduced the error rate, hitting a historic accomplishment.
Since qubits – quantum bits – are notoriously unstable, quantum computer companies use redundancy to improve accuracy, with multiple physical qubits combining into a single “logical” qubit.
Google also claims that this is one of the first times the error correction was performed in real time. And that the logical qubits have a longer lifetime than the individual physical qubits do.
It’s the first system that’s “below threshold,” Neven says. “It’s a strong sign that useful, very large quantum computers can indeed be built. Willow brings us closer to running practical, commercially-relevant algorithms that can’t be replicated on conventional computers.”
And, in an aside that should be of interest to any sci-fi fan, he says that the speed of the computation “lends credence to the notion that quantum computation occurs in many parallel universes, in line with the idea that we live in a multiverse.”
In a video presentation also released on Monday, Neven added that this week’s breakthrough means that practical commercial applications are as close as five years away. Most other experts estimate that this date is at least ten years in the future.
NIST, for example, recommends that federal agencies stop using classical encryption in 2035 and switch to quantum-safe encryption instead.
Industry reality check
Google’s achievement might seem impressive, but industry experts warn that there’s still a long way to go before practical use of quantum computers.
“Could I solve a problem today that I couldn’t solve yesterday? The answer is no,” says Yuval Boger, chief commercial officer at QuEra Computing. “Nothing has changed in that sense.”
QuEra is a quantum computing company that uses the “neutral ions” approach to building qubits, in contrast to Google’s “superconducting circuits” approach. In October, QuEra announced that it received a “strategic investment” from Google, though it did not disclose the sum. And, earlier this year, QuEra announced its own breakthrough in error correction.
“But they’ve passed one more waypoint,” Boger adds.
The first waypoint was to figure out whether quantum computing even works. That’s already been settled — it works. The second waypoint is whether the errors can be corrected. That waypoint has been achieved this year, he says, this week by Google — and, earlier, by his company.
“The third step – and we’re not there yet – is if it can scale,” he adds. “We’re now entering that stage.”
What about the breathtaking speed that Willow demonstrated? It turns out that the benchmark Google used was a random circuit sampling algorithm with no real applications.
“The new tech is not immediately actionable from a business point of view,” says Stefan Leichenauer, vice president of engineering at quantum computing software company SandboxAQ, which was spun off from Google in 2022. “The problems of scale are still present, and there’s a long way to go before they are solved.”
Security implications
While practical quantum computing applications might still be many years away, security experts say the timeline for quantum-safe encryption preparation needs to be accelerated.
“Quantum computers will eventually break the asymmetric encryption we’ve relied on for over 50 years,” says Jordan Kenyon, chief scientist in Booz Allen Hamilton’s quantum practice. “It is a question of when, not if. If you are a CISO or CIO and are not actively planning, prototyping, or implementing the PQC algorithms NIST standardized this summer, there is no better time.”
It’s very likely that nation states will deploy quantum computers to crack the most sensitive messages even before the technology is widely available for commercial use. Plus, there are the “harvest now, decrypt later” attacks where adversaries vacuum up valuable communications or data, then decrypt them when the technology becomes available, says Forrester analyst Brian Hopkins.
“Even if quantum decryption is a decade away, attackers could steal encrypted data today,” he says. “Companies should begin transitioning to post-quantum cryptographic algorithms.”
And, to maintain flexibility as these algorithms evolve, companies should adopt a “cryptographic agility” approach, he adds, allowing them to swap out encryption methods as needed.
Planning ahead
Beyond cybersecurity, there are other steps that companies can take to prepare for a quantum future.
Google’s Neven, for example, suggests that researchers, engineers and developers start educating themselves. There are even free resources out there, including a new quantum error correction course that Google launched this week on Coursera.
“Awareness and training is always a good thing,” says Jon France, CISO at ISC2 (International Information Systems Security Certification Consortium). “If not only for security reasons, but also for business opportunities.”
There’s always a chance that quantum computing will have a breakthrough moment that advances the timeline, he says. In fact, Google’s Willow announcement might just be one of those breakthrough moments.
“This may not have a practical impact for day-to-day use, but it continues to highlight the advances in the field and may move planning from long-term to mid-term,” he says.
Booz Allen Hamilton’s Kenyon suggests that companies should be working now to identify mission-critical use cases where quantum technologies may offer an advantage, prototype applications, and start investing in a workforce that can make it possible.
And, since there’s a shortage of quantum experts, this means a long-term commitment to upskilling.
“Quantum demands a breadth and depth of talent that is difficult to recruit, retrain, and retain,” he says. “But a diverse workforce is critical to identifying and delivering on the mission-critical use cases that will unlock the technology’s real-world potential.”
Source:: Network World