Google
The new Willow chip
Google has unveiled a new chip that it says takes five minutes to solve a problem that would currently take one of the world's fastest supercomputers seven billion years – that's a 10 followed by 24 0 – to solve.
The chip is the latest development in a field known as quantum computing, which attempts to use the principles of particle physics to create a new type of mind-bogglingly powerful computer.
Google says its new quantum chip, dubbed “Willow,” incorporates key “breakthroughs” and “paves the way for a useful, large-scale quantum computer.”
However, experts say Willow is, for now, a largely experimental device, meaning a quantum computer powerful enough to solve a wide range of real-world problems is still years – and billions of dollars – away. –.
The quantum dilemma
Quantum computers work in a fundamentally different way than the computer in your phone or laptop.
They harness quantum mechanics – the strange behavior of ultra-tiny particles – to solve problems much faster than traditional computers.
It is hoped that quantum computers will eventually be able to use this ability to significantly speed up complex processes, such as the creation of new drugs.
There are also concerns that it could be used for nefarious purposes, such as breaking certain types of encryption used to protect sensitive data.
In February, Apple announced that the encryption that protects iMessage chats was now “quantum-proof” to prevent them from being read by future powerful quantum computers.
Hartmut Neven runs the Google quantum AI lab that created Willow and describes himself as the project's “optimistic leader.”
He told the BBC that Willow would be used in some practical applications – but declined, for now, to provide further details.
But a chip capable of commercial applications won't appear until the end of the decade, he said.
Initially these applications would be the simulation of systems where quantum effects are important
“For example, relevant when it comes to designing nuclear fusion reactors to understand how drugs work and pharmaceutical development, it would be relevant to developing better car batteries and another long list of such tasks.”
What is quantum computing?
Companies around the world are racing to create a revolutionary new generation of computers.
Apples and oranges
Mr Neven told the BBC that Willow's performance meant it was the “best quantum processor built to date”.
But Professor Alan Woodward, a computer science expert at the University of Surrey, says quantum computers will be better at a number of tasks than current “classical” computers, but will not replace them.
He warns against overestimating the importance of Willow's success on a single test.
“You have to be careful not to compare apples and oranges,” he told the BBC.
Google had chosen as a performance benchmark a problem “tailor-made for a quantum computer” and this did not demonstrate “a universal acceleration compared to classical computers”.
Still, he said Willow represented significant progress, particularly in so-called error correction.
In very simple terms, the more useful a quantum computer is, the more qubits it has.
However, a major problem with this technology is that it is error-prone – a trend that previously increased with the number of qubits on a chip.
But Google researchers say they have reversed this trend and managed to design and program the new chip in such a way that the error rate decreases throughout the system as the number of qubits increases.
This is a major “breakthrough” which has made it possible to meet a major challenge that the field has been looking for “for almost 30 years”, believes Mr. Neven.
He told the BBC it was comparable to “if you had a plane with one engine it would work, but two engines are safer, four engines are even safer.”
Errors pose a significant obstacle to creating more powerful quantum computers and this development is “encouraging for everyone striving to build a practical quantum computer”, Professor Woodward said.
But Google itself notes that to develop practically useful quantum computers, the error rate will still need to be much lower than that shown by Willow.
The Google team is working on the cryostat that holds the chip and keeps it very cold
Willow was manufactured in Google's new purpose-built manufacturing facility in California.
Countries around the world are investing in quantum computing.
The UK recently launched the National Quantum Computing Center (NQCC).
Its director, Michael Cuthbert, told the BBC he was wary of the language that fueled the “hype cycle” and believed Willow was more of a “milestone rather than a breakthrough.”
Nonetheless, it was “clearly a very impressive piece of work.”
Ultimately, quantum computers could help solve a range of tasks, including “logistical problems such as distributing cargo on planes or routing telecommunications signals or stored energy across the national grid,” he said. he declared.
And there were already 50 quantum companies in the UK, attracting £800 million in funding and employing 1,300 people.
On Friday, researchers from the University of Oxford and Osaka University in Japan published a paper highlighting the very low error rate in a trapped ion qubit.
Their approach is different to creating a quantum computer capable of operating at room temperature, whereas Google's chip must be stored at ultra-low temperatures to be effective.
