What is quantum computing?

The first thing to know about quantum computing is that it won’t displace traditional, or ‘classical’ computing. The second thing to know: Quantum computing is still a nascent technology that probably won’t be ready for prime time for several more years.

And the third thing you should know? The time to start protecting your data’s security from quantum computers is now.

Here’s an overview of what you should know about quantum computing.

Quantum computing explained

The classical computers we’ve used for decades use a sequence of binary bits. Each bit is always in one of two definitive states – 0 or 1 – that act as on and off switches to drive computer functions. In contrast, a quantum computer uses quantum bits, or qubits. Each qubit can represent both a 0 and a 1 simultaneously. Consequently, quantum computers can store far more information than classical computers and have the potential to process massive amounts of calculations running in parallel within seconds—far faster than the fastest classical computers.

Quantum-computing terms

Briefly, a few quantum computing terms to know are:

Quantum mechanics, aka quantum physics. A theory in physics that describes nature in terms of atoms and subatomic particles. Quantum computers are based on quantum mechanical phenomena such as superposition and entanglement.

Superposition. A qubit can be more than one thing at a time through a quantum-mechanics principle called superposition. Superposition gives quantum computers their speed and parallelism, enabling them to work on millions of computations at once, says Matthew Brisse, Vice President of Research for Data Center and Cloud Infrastructure with the Gartner for Technical Professionals service.

Put another way: With a classical computer bit, a cat is either dead or alive. With a quantum-computer qubit, a cat can be both dead and alive, thanks to superposition. (For that analogy, which is often used when people explain quantum computing, we can thank an Austrian physicist who devised the Schrödinger’s cat thought experiment in 1935.)

Entanglement is when qubits are linked with other qubits, so that the state of one qubit can depend upon the state of another. With entanglement combined with superposition, quantum computers have the potential to simultaneously process a vast number of possible outcomes.

The bottom line: “With quantum computing, we can do things in massively parallel systems that we couldn’t do before,” says Brisse.

Quantum-computing origins

During a 1959 lecture, physicist Richard Feynman—who helped develop the atomic bomb during World War II—raised the possibility of quantum computing. In the early 1980s, the concept of quantum computing started to talk hold, thanks to the work of Feynman, Paul Benioff and others.

“By the early 1980s, it was clear that in addition to conventional computing, we could do computations using the rule of quantum mechanics,” says Bob Wisnieff, IBM’s CTO of quantum computing. “The question was, if you had a computer built on quantum mechanics, what kinds of computations could be done easier and faster? That question kicked off research into quantum computing at IBM.”

Why we’re talking about quantum computing now

To be sure, quantum computing is still in its infancy. Only 1 percent of organizations are budgeting for quantum computing projects, according to Brisse. But that’s expected to grow to 20 percent by 2023.

So, why is quantum computing blipping on our radar screens now?

“We’re reaching the limits of what a classical computer can do,” says Ashish Nadkarni, Program Vice President of Computing Platforms, Worldwide Infrastructure at IDC. Many (though not all) experts believe that the phenomenon of Moore’s Law is coming to an end or is at least slowing to a crawl. At the same time, a growing number of companies, such as Google, have “an insatiable need for compute power,” Nadkarni says. Thus, the growing interest in quantum computing.

Quantum computing applications

Currently, quantum computers can only run limited business applications and specific quantum algorithms. Some believe quantum computers will always be specialized vs. general purpose. And most experts in the field say that quantum computers will integrate and work with, rather than replace, classical computers.

Given that, quantum computers are most likely to be used when there’s a huge volume of data to process within seconds. “Financial-services companies could benefit from quantum computing, especially with services where the volume of data related to trades is high, and they want to simulate outcomes in seconds,” says Nadkarni.

Other likely applications: Drug and biotech research, gene editing and simulation, quantum chemistry, artificial intelligence, traffic pattern analysis, weather forecasting and cryptography.

“Quantum computers will be particularly good at solving big optimization problems, such as shipping logistics,” says Brisse.  

Quantum computing and IBM

IBM is among classical computing giants that are pioneering in the nascent field of quantum computing. The company helped create the field of quantum computing, and it’s been an important research area for the company for decades.

On May 4, 2016, IBM announced the IBM Quantum Experience (since shortened to IBM Q Experience), the world’s first Quantum Computing as a Service (QCaaS) offering that enables the general public to connect to IBM quantum computers via the cloud. The goal: Enable users to run experiments, explore tutorials and simulations, and otherwise get a taste for quantum computing.

Initially, IBM’s Q Experience provided access to a 5-qubit IBM Q quantum computer located in IBM’s T.J. Watson Research Center in New York. Since then, the Q Experience also offers access to 16-qubit systems.

Additionally, in December 2017, IBM launched the IBM Q Network, a global consortium of Fortune 500 enterprises, research labs and academic organizations focused on exploring practical quantum computing applications for business and science.

As of this writing, 80,000 IBM Q Experience users have run more than 4 million experiments and generated more than 65 research publications, according to IBM.

Other quantum computing players include Google, Intel, Microsoft and startups such as Rigetti Computing, D-Wave Systems, Inc., and Zapata Computing.

What enterprises should do to prepare for quantum computing

Move toward quantum-safe encryption. Because they can crunch unprecedented amounts of numbers in practically no time, there’s a fair amount of hand-wringing that for quantum computers might one day crack even the strongest encryptions available today.

“If you have a big-enough machine, a quantum computer could instantly break all encryption,” says Arvind Krishna, Senior Vice President of Hybrid Cloud and Director of IBM Research. He predicts that won’t happen for at least five years. Even so, anyone who wants to ensure their organization’s data is safe for more than 10 years should start migrating toward quantum-safe encryption now, such as lattice cryptography. (Krishna made his comments May 15 in San Francisco during a quantum computing forum hosted by Churchill Club.)

Further reading:

“Why quantum computing has the cybersecurity world white-knuckled”

Consider quantum computing as a service (QCaaS) vs. investing in quantum computers. Given how rapidly quantum computing technology is changing, among other factors, most experts believe organizations will subscribe to QCaaS offerings. “It’s all pay-as-you-go, without any capital expenditures,” says Nadkarni.

Look for problems you can’t solve on a classical computer. When trying to decide if quantum computing is right for your organization, start by asking your data scientists if there are problems they can’t solve with classical computers today, says Brisse. “Those problems are great candidates for quantum computers.”

Start educating yourself or your team now. About 1,500 schools around the world offer quantum-computing courses as part of their curriculum, and the availability of online training is growing dramatically, Wisnieff says. Education will be essential to quantum computing’s future, of course. “There won’t be any quantum computing without an educated workforce to make it happen,” he adds.

Be patient. We’re looking at a five-year horizon before quantum computing really takes hold, during which time we’ll begin to see applications where quantum computers can truly offer some level of quantum advantage (or quantum supremacy), says Wisnieff.

Proceed with caution. “There are so many different quantum-computing techniques, there’s no standard, the processors are all one-off processors right now,” says Brisse. “At this point, we’re literally turning on a circuit and yelling ‘Woo-hoo, we’ve got a circuit!’ Bottom line, we don’t know what we don’t know yet about quantum computing. It could be a dud, like cold fusion, or it could be the cat’s meow.” Perhaps it could even be the Schrödinger cat’s meow.