Google says it achieved ‘Quantum Supremacy’ but IBM isn’t very impressed

Google on Wednesday announced achieving 'Quantum Supremacy' with its Sycamore processor. Google's research team went on to claim that the new chip delivered a target computation in just over 3 minutes which the world's fastest super computer would have taken 10,000 years to produce a similar output. While Google's new feat is being praised by many, IBM researchers aren't very impressed. IBM has been one of the top technology companies working on commercial quantum computers.

Researchers at IBM said that Google was over-selling the 'Quantum Supremacy'. The company in a blog post earlier this week claimed that a supercomputer with additional disk storage can solve the random number problem in at most 2-1/2 days, with greater fidelity - or accuracy.

IBM researchers also pointed out that Google risks misleading public by suggesting that the new computers could replace the standard computers. Researchers said that the quantum computers will "never reign supreme" over classical computers. Instead, these computers will work "in concert" with them.

"This particular notion of "quantum supremacy" is based on executing a random quantum circuit of a size infeasible for simulation with any available classical computer. Specifically, the preprint shows a computational experiment over a 53-qubit quantum processor that implements an impressively large two-qubit gate quantum circuit of depth 20, with 430 two-qubit and 1,113 single-qubit gates, and with predicted total fidelity of 0.2%. Their classical simulation estimate of 10,000 years is based on the observation that the RAM memory requirement to store the full state vector in a Schrödinger-type simulation would be prohibitive, and thus one needs to resort to a Schrödinger-Feynman simulation that trades off space for time," wrote researchers in a blog post referring to Google's leaked study on the 'Quantum Supremacy.'

ALSO READ: IBM Q System One brings commercial quantum computers closer to reality

Google's 'quantum supremacy' claim may be up for a debate but the latest demonstration shows an immense potential in the technology. The feat also indicates that the technology is finally coming of age after having stayed a concept for several years.  

"The quantum supremacy milestone allegedly achieved by Google is a pivotal step in the quest for practical quantum computers," John Preskill, a Caltech professor who originally coined the "quantum supremacy" term, wrote in a column after Google's paper was leaked.

It means quantum computing research can enter a new stage, he wrote, though a significant effect on society "may still be decades away."

The calculation employed by Google has little practical use, Preskill wrote, other than to test how well the processor works. Monroe echoed that concern. "The more interesting milestone will be a useful application," he said.

(with inputs from agencies)