By Stephen DeAngelis
During the 2014 NBA draft, ESPN analyst Fran Fraschilla famously said about Brazilian draftee Bruno Caboclo, “He’s two years away from being two years away.” Borrowing from Fraschilla, one could easily say, “Quantum computing is two years away from being two years away.” Astrophysicist Adam Frank explains, “From breathless media accounts, many people assume that quantum computing machines are just around the corner. It turns out that is not the case at all.”[1] Gartner analysts agree with that assessment. Journalist Berenice Baker reports, “Quantum computing did not feature in the 2024 Gartner Top 10 Strategic Technology Trends report.”[2] To find out why, she contacted Gartner Vice President Bart Willemsen who offered the following explanation:
“This is an excellent question, especially because of the enormous impact quantum computing will have. … The immediate response to quantum computing is not expected to be very actionable in 2024 or the immediate years after. … Our QC analyst group is adamant that before the end of this decade, we will see the true impact, yet not in the current strategy response time.”
In other words, looking for a universal quantum computer remains a waiting game.
Quantum Computing Challenges
Frank notes that theories about the viability of quantum computers were developed decades ago. So he asks the obvious question, “Now it’s many decades later, so why don’t we have quantum computers in our pockets replacing our cell phones?” The answer to that question lies in the term “quantum.” Things at the quantum level of physics are both very small and very weird. At the heart of quantum computing is the quantum bit or qubit. And, as Frank explains, “Qubits, it turns out, are very delicate.” Frank explains the importance of the qubit:
“Thanks to the weirdness of quantum physics, a quantum system can be in two mutually incompatible states at the same time. For example, imagine that an electron is placed in a box divided into two sections. Classically, the ‘state’ of this system only can be the electron occupying one section of the box or the other. Quantum mechanical states, however, can be ‘superposed,’ meaning the electron can be in both sections of the box at the same time. It’s only when a measurement is performed on the electron (that is, someone looks at it) that the superposed state is said to ‘collapse,’ and it’s observed in one or the other section of the box. A system like an electron and the two-section box is called a quantum bit or a ‘qubit.’”
Qubits are so tiny and so fragile that they can easily be collapsed from their superimposed state. Freelance journalist David Nield reports, “Keeping qubits stable — those quantum equivalents of classic computing bits — will be key to realizing the potential of quantum computing. Now scientists have found a new obstacle to this stability: natural radiation.”[3] He adds, “Through a series of experiments that altered the level of natural radiation around qubits, physicists have been able to establish that this background buzz does indeed nudge qubits off balance in a way that stops them from functioning properly.” That’s a problem. And natural radiation isn’t the only problem. Los Alamos National Laboratory scientists, Scott Pakin and Patrick Coles, explain, “This loss of coherence (called decoherence), caused by vibrations, temperature fluctuations, electromagnetic waves and other interactions with the outside environment, ultimately destroys the exotic quantum properties of the computer. Given the current pervasiveness of decoherence and other errors, contemporary quantum computers are unlikely to return correct answers for programs of even modest execution time.”[4]
Researchers are frantically working on ways to catch and correct quantum computing errors. Nevertheless, the fragility of quantum systems remains a challenge.
How Close are Quantum Computers?
Science writer Jacinta Bowler reports that the leading companies researching quantum computing are making progress, but still struggling with errors.[5] She reports:
“Google’s machine — called the Sycamore processor — has currently got 70 qubits all lined up and connected. In 2019, the researchers had claimed they’d reached ‘quantum supremacy.’ More recently, they went more specific — suggesting that a top-level supercomputer would take 47 years to do the calculations that Sycamore managed to do in seconds. IBM says its 433-qubit quantum computer called Osprey could soon start having real-world applications. However, while IBM is further ahead in number of qubits, it is still struggling with the same error issues as other quantum systems. To get to a quantum computer that could rival supercomputers at actual tasks, you need hundreds of thousands, or millions of qubits rather than a few hundred. But the more qubits you have the more errors that end up in the system.”
“So where are we at with quantum computing?” Bowler asks. Her conclusion, “Not very far at all.” That seems to be a widely held opinion. Journalist Richard Speed asked Raymond Simmonds, a physicist at the National Institute of Science and Technology, how close he thought quantum computing was to catching up with the hype. He told Speed, “Useful results might show up within the next few years.” Speed notes, however, that Simmonds believes the point at which a quantum computer could perform a calculation simply not possible with regular classical computers is “probably still ten years away.” Speed concludes, “And, of course, that estimate is for a quantum computer designed for a specific task. Simmonds estimates a universal quantum computer — one that could be reprogrammed in a similar way to classical computers — was still 20 years away.”
Concluding Thoughts
Although quantum computing may not be two years away from being two years away, Bowler believes we shouldn’t be discouraged. She reminds us, “The first design of a computer — called the differential engine — was designed by a mathematician Charles Babbage in the 1820s. But it wouldn’t be built in Babbage’s lifetime.” It would take another 120 years for technology to catch up to theory. Professor Tom Stace, the Deputy Director of the ARC Centre of Excellence in Engineered Quantum Systems (EQUS), told Bowler, “It could be that we’re somewhere between Charles Babbage and the valve. We’ve got the idea, we know in principle we can make this thing. We just don’t know if we have the engineering chops to do it.” I’m betting we do have the chops — even if it takes a few more years in the waiting room.
Footnotes
[1] Adam Frank, “Is quantum computing hype or almost here?” Big Think, 17 August 2023.
[2] Berenice Baker, “Why Gartner Excluded Quantum Computing from its 2024 Top Tech Trends,” IoT World Today, 20 October 2023.
[3] David Nield, “We Just Found Another Obstacle For Quantum Computers to Overcome – And It’s Everywhere,” Science Alert, 30 August 2020.
[4] Scott Pakin and Patrick Coles, “The Problem with Quantum Computers,” Scientific American, 10 June 2019.
[5] Jacinta Bowler, “Where are we at with quantum computing?” Cosmos, 25 September 2023.
[6] Richard Speed, “Why quantum computing might be much closer to becoming a reality than we think,” ITPro, 25 September 2023.
