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There are reports are that Google (GOOG) has demonstrated quantum supremacy. In quantum computing, quantum supremacy means that a quantum computer is able to perform a calculation that is practically impossible for a classical computer. Before we fear and weep for the western dream, ScienceAlert explains that we can’t be sure of the claim.

Shortly after the research article was uploaded to the NASA site it was withdrawn for unknown reasons. The news was originally broken by the paywalled Financial Times, which reported both seeing the paper and also that it was subsequently taken down. Now there are only copies of the original paper available online. Further, Google has not officially explained to anybody what’s going on, sparking no end of speculation online about what has or hasn’t happened.

Assuming the briefly released paper, is real – why is this important? Wired explains that the Google researchers used a quantum processor called Sycamore, with 54 qubits. It tackled a random sampling problem – that is, checking that a set of numbers has a truly random distribution. ScienceAlert says the experimental quantum processor took about 200 seconds to solve a particular computational problem.

As part of the experiment, they set a version of the same challenge to some powerful Google server clusters, as well as to the current world’s fastest supercomputer, the IBM-built Summit supercomputer at Oak Ridge National Lab. The state-of-the-art supercomputer would require approximately 10,000 years to perform the same task.

According to copies (PDF) of the vanished report,

This dramatic speedup relative to all known classical algorithms provides an experimental realization of quantum supremacy on a computational task and heralds the advent of a much-anticipated computing paradigm

In the Wired article, John Preskill, the Caltech professor who coined the term “quantum supremacy,” calls the breakthrough, if accurate, ”truly impressive achievement in experimental physics.” But he and other experts, and even Google’s own paper, caution that the result doesn’t mean quantum computers are ready for practical work. Professor Preskill explains, “The problem their machine solves with astounding speed has been very carefully chosen just for the purpose of demonstrating the quantum computer’s superiority.”

Professor Preskill told Wired,  it’s unclear how long it will take quantum computers to become commercially useful; breaking encryption—a theorized use for the technology—remains a distant hope. “That’s still many years out,” says Jonathan Dowling, a professor at Louisiana State University and New Scientist said although that is impressive, there is no practical use for it.

Will Oliver, a quantum specialist at MIT, told Technology Review, the computing milestone is similar to the first flight of the Wright brothers at Kitty Hawk in aviation. He said it would give added impetus to research in the field, which should help quantum machines achieve their promise more quickly.

New Scientist says there are plenty of hurdles left to overcome before quantum computing hits the big time. The author cites a number of steps:

For a start, the processors need to be more powerful. Google’s Sycamore quantum computer, consisted of only 54 qubits. For quantum computers to really come into their own, they will probably need thousands. Scaling up the number of qubits won’t be easy. Qubits must be isolated from vibrations as they can be easily disturbed.

Next quantum computers need error-correcting codes. Classical computers have mechanisms to make sure that when little mistakes happen they are automatically rectified.

The same will be needed for quantum computers, especially considering the delicate nature of qubits. The challenge now is to build a quantum computer that has quantum supremacy, as well as error-correcting codes.

The final, biggest step is to actually do something useful. Google’s quantum computer tackled a task specifically tailored  to prove quantum supremacy, not do anything useful.

New Scientist called the achievement impressive, there is no practical use for it. Ciarán Gilligan-Lee at University College London said, “We shouldn’t get too carried away with this … but there’s still a long way to go.”

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This bench-marking task is a proof of concept. SkyNet is not coming –  yet.

Combining quantum with machine learning and AI may be a different story. But for a year or so we are probably safe. Unless of course, some TLA that is already using quantum computing made the paper disappear.

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Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedIn, Facebook, and Twitter. Email the Bach Seat here.