Google quantum computer leaves old-school supercomputer in the dust – CNET, Cnet.com

                                                                                                          

A Google quantum computer has far outpaced ordinary computing technology, an achievement calledquantum supremacythat’s an important milestone for a revolutionary way of processing data.Google disclosed the results in the journal Natureon Wednesday. The achievement came after more than a decade of work at Google, including the use of its own quantum computing chip, called Sycamore.

” Our machine performed the target computation in 200 seconds, and from measurements in our experiment we determined that it would take the world’s fastest supercomputer 10, 00 0 years to produce a similar output, “Google researchers saidin a blog post about the work.

The achievement, whichleaked into the limelightin September with apremature paper publication, doesn’t mean the beginning of the end for classical computers, at least in the view of today’s quantum computing experts. Quantum computers are expected to be good at some particular chores – optimizing investment portfolios and developing new drugs at the molecular level, for example – but not most of what we do today on computers.

Google’s result does offer evidence, though, that quantum computers could break out of research labs and headtoward mainstream computing

Quantum computing researcherScott Aaronson likened the step to landing on the moonin terms of momentousness. And in a tweet Wednesday, Google Chief ExecutiveSundar Pichai called ita “big breakthrough.”

A vast industry is devoted to improving classical computers, but a small number of expensive labs at companies such as Google, Intel, Microsoft, Honeywell,Rigetti Computingand IBM are pursuing general-purpose quantum computers, too. They’re finicky devices, running in an environment chilled to just a hair’s breadth above absolute zero to minimize the likelihood they’ll be perturbed. Don’t expect to find a quantum computer on your desk.

Google’s speed test has applications to computing work like artificial intelligence, materials science and random number generation, the paper said.

However, physicist Jim Preskill, who came up with the term “quantum supremacy” in 2012, dashed some cold water on that idea. Google’s chosen test was good for showing quantum computing speed but “not otherwise a problem of much practical interest,”Preskill saidin October after the paper’s premature release.

Quantum vs. classical computers

Nearly every digital device so far, fromENIAC in 1945toApple’s iPhone 11in 2019, is a classical computer. Their electronics rely on logic circuits to do things like add two numbers and on memory cells to store the results.

Quantum computers are entirely different, reliant instead on the mind-bending rules of physics that govern ultrasmall objects like atoms.

Where classical computers store and process data as individual bits, each a 1 or a 0, quantum computers use a different foundation, called a qubit. Each qubit can store a combination of different states of 1 and 0 at the same time through a phenomenon called superposition.

Not only that, but multiple qubits can be ganged together through another quantum phenomenon called entanglement. That lets a quantum computer explore a vast number of possible solutions to a problem at the same time.

Exponential speedups

In principle , a quantum computer’s performance grows exponentially: add one more qubit, and you’ve doubled the number of solutions you can examine in one fell swoop. For that reason, quantum computing engineers are working to increase the number of qubits in their machines.

“We expect that their computational power will continue to grow at a double-exponential rate, “the Google researchers said in their paper. That’s even faster than the single exponential improvement charted for classical computer chips by Moore’s Law.

Google’s machine had 54 qubits, though one wasn’t working right, so only 53 were available . That happens to match the number inIBM’s most powerful quantum computer.

But qubit count isn’t everything. Unavoidable instabilities cause qubits to lose their data. To counteract that problem, researchers are also working on error-correction techniques to let a calculation sidestep those problems.

IBM challenges Google’s quantum results

IBM is a major quantum computing fan, but it questioned Google’s prematurely released results in a blog post Monday.

“We argue that an ideal simulation of the same task can be performed on a classical system in 2.5 days and with far greater fidelity, “IBM researchers wrote. They suggested different algorithms and a different classical computer design in apreprint paper of their own.

Google said it welcomes improvements to quantum computer simulation techniques but said its overall result is “prohibitively hard for even the world’s fastest supercomputer, with more double exponential growth to come. We’ve already peeled away from classical computers, onto a totally different trajectory.”

Intel didn’t offer an opinion on Google’s results, but did say quantum supremacy is “a strategic benchmark.”

“We are committed to moving quantum from the lab to commercialization,” said Jim Clarke, Intel Labs’ director of quantum hardware, in

Cracking your encrypted communications? Not yet

One quantum computing ability, mathematically proved with an idea called Shor’s algorithm, is cracking some of today’s encryption technology.

However, that will require vastly larger quantum computers and new technology breakthroughs to deal with error correction.

“Realizing the full promise of quantum computing (using Shor’s algorithm for factoring, for example) still requires technical leaps, “the researchers said in their paper.

And at the same time, the US government and others are working on” post-quantum “cryptography methodsto withstand quantum computing cracking abilities.

So for now at least, quantum computing, while radically different, isn’t blowing up the tech industry.

First published Oct. 23, 2: 15 am PT.
Update, 3: 09 am PT:Adds more detail and comment from Google CEO.