A new essay by leading scientist Sankar Das Sarma argues that many claims about quantum computers are overblown, stating that current practical applications for quantum computers are, in fact, limited. But not all experts agree with the assessment, instead believing it’s only a matter of time before they deliver on their potential. “We’re seeing more and more potential use cases for quantum computing and proof of concept projects that validate that quantum computing could help achieve advantages,” Scott Laliberte, managing director and global leader of consulting firm Protiviti’s Emerging Technology Group, told Lifewire in an email interview. “For instance, we’re helping clients with proof of concepts in the area of portfolio optimization, and the results are extremely promising.”

Quantum Doubts

Companies like IBM are investing billions of dollars in quantum computing, a type of computation that harnesses the collective properties of quantum states, such as superposition, interference, and entanglement, to perform calculations. But making a quantum computer that can outperform regular computers is a long way away from reality, Sarma says. He takes particular aim at the idea that a quantum computer can find the prime factors of large numbers much faster than modern computers. If this theory proves correct, quantum computers could crack standard cryptography, but Sarma says making a computer that can accomplish this task has proven impossible. Scott Buchholz, the emerging technology leader and CTO for Government & Public Services at Deloitte, agrees with Sarma’s conclusion that, so far, there is no evidence of broad “quantum supremacy,” where a problem can be solved by a quantum computer in a consistently superior fashion to what we can do with current computers. “Narrower claims of good or improved results should be evaluated carefully as the art of the possible is evolving rapidly,” Buchholz told Lifewire in an email interview. “With that said, it’s important to remember that we’ve had 60+ years to mature the capabilities of classical computers, whereas we’re still very early in the evolution of quantum computers.” In the near term, quantum annealers (a special class of quantum computers that are easier to build but more limited in problems they can attack) continue to improve their ability to support complex problems, Buchholz said. For the more general “gate-based architectures,” a variety of competing technologies promise different, improving performance characteristics.

Not Yet Practical?

Itamar Sivan, CEO of Quantum Machines, says that it’s just a matter of time before quantum computing lives up to its promise. Quantum computing can potentially impact the world in areas from cryptography to improving AI and even drug/vaccine discovery, he said.  “For right now, we’re in the phase of development where the hype is huge, and people are talking about the very advanced use cases. But we, as an industry, can’t quite deliver the actionable results yet, and that could understandably lead some to think that quantum computers are overhyped,” Sivan told Lifewire in an email interview.  “Just remember that in the 1980s computers didn’t even have color monitors, and today the smartphone many are reading this on is a far more powerful and smaller device than we ever could have imagined then,” Sivan added. Part of the problem holding back quantum computing is that the hardware is useless without software. And there needs to be significant improvements on the software side of quantum computing, Yuval Boger, Chief Marketing Officer at quantum computing company Classiq, said in an email interview.  “The way quantum computing is written today is equivalent to writing classical software in assembly language or creating websites with raw HTML code,” Boger said. “We expect to see the emergence of high-level functional programming models, equivalent to C++ or Wix in the classical world, allowing users to specify the desired behavior while a computer automates the underlying implementation. Expect the combination of stronger hardware and advanced software to fulfill the promise of quantum.” Practical applications for quantum computers aren’t far off, some observers insist. Within the next three years, chemical simulation and some financial calculations will be executed on quantum computers, Boger said.  But don’t expect personal at-home quantum computers any time soon, if ever, Sivan said. “Unfortunately, people with advanced degrees in quantum physics or experience in quantum hardware development aren’t a dime a dozen,” he added. “And we need to continue to develop our academic programs so that they can produce the amount of talent that the market requires.”