Dive into the quantum computing qubit with IBM's Bob Sutor

Though the idea of building a quantum computer originated in the 1960s, the technology is seeing a recent uptick in interest and investment and materialization. Yet, even with industry giants building these incredibly innovative systems, there's still a lot of mystery around what quantum computing -- and the qubit -- is and how enterprises can use the technology.

IBM is a big proponent of quantum development with its employees, research departments and scientists helping to develop such systems since the mid-'90s. But developing these systems isn't the company's only focus; IBM is actively working to make quantum computing accessible through its IBM Q Experience, growing data points and business partnerships with the IBM Q Network.

Bob Sutor, vice president of IBM quantum ecosystem development at IBM Research, also knew education was an important part of quantum adoption. This led him to write Dancing with Qubits: How quantum computing works and how it can change the world.

Here, Sutor talks about quantum computing trends, challenges and how his book can help IT professionals and curious minds build an effective foundation about the quantum computing qubit -- and about the technology it supports.

Editor's note: The following has been edited for length and brevity.

Where would you say quantum computing is on the technology maturity scale?

Bob Sutor: I would put that in context by comparing it to what we can already do on classical computing, because the question is, 'Why do we need quantum computing anyway?' There's this separation between what we can practically do, and the ones that are tractable, and the ones that are intractable.

Click to learn more about
the foundations of
quantum computing and
qubits.

Intractable one for the [use cases] that would take too much time or too much memory, or simply would not be accurate enough about time we want to give them, or possibly the computing resources would cost so much money.

[These intractable problems] are where we would focus with quantum computers. And so now, at this point, you can say, 'Well, we've identified a set of problems to which we might be able to attack with a combination of classical computing, plus some help from quantum computing.'

We estimate that by mid-decade we will start to see some points where quantum computers can breakthrough and provide some answers to problems that are currently in track in this decade. … A lot of things must come together and that's why we're all working together. The more people on this, the better.

In fact, it's not just governments, it's not just research; it's companies like startups, JP Morgan Chase and Exxon Mobil. We have over 100 different organizations in what we call the IBM Q Network and we're all focused on solutions.

Why do you think businesses find quantum computing so appealing?

Sutor: It's anyone who has a problem that isn't tractable or they're just not happy with the performance of the systems they have in their workflow. It's about optimizing the risk profile.

While we may initially talk about quantum computing at banks or investment houses, it really is a very broad cross-industry problem. It goes back to how quickly I [can get] my answer to get a good risk assessment, and what is the size of the portfolio [or data set]?

For [scientific use cases], it turns out [modeling chemical molecular reactions] requires ridiculous amounts of computing power [to only] approximate them, not even very well for very small molecules. But to really move chemistry and biochemistry modeling from the laboratory to what we can do inside computers faster and more accurately is going to require something like quantum computing.

What are some of the common misconceptions around quantum computing?

Sutor: The first misconception is that [quantum computers] will completely replace the computers we have today, such as your phone.

We [at IBM] do believe that this is going to be very possibly the most important computing technology of the century.

Another misconception is that people are buying quantum computers and putting them into their own private data center. Quantum computing is really a cloud technology today. We're making tremendous progress year over year in improving the performance of these machines. It makes far more sense for us to put them in the IBM cloud data centers and operate faster models with greater capacity and so forth, and you just access that capacity through the web.

I would say the third misconception is that you can do quantum computing but just with classical computers and that you could completely simulate everything going on in a quantum computer. Yes, we have software simulators that, for small problems, can pretend to be a quantum computer for various reasons, but you can make those [simulations] so large.

If [there's no] actual quantum computing hardware, then you're not really doing quantum computing; you're pretending to do quantum computing on the classical hardware systems.

Why do you think it's important to develop a knowledge of quantum computing and make it accessible?

Sutor: There is something about the nature of those problems that I think is beyond the understanding of most people; if they were fully understood, we would solve them. There's something lurking out there -- both about the difficulty of these problems and how you would go about it; attacking with quantum computing is not simply a slight variation of classical computer.

I think that we have to make quantum computing accessible to as many people as possible. One way IBM is doing it is by making 15 quantum computers available on the cloud today. But then for the understanding, it [becomes] how do you teach people [and] change the way they approach building software and think about things.

Now, in my case, I've been coding for over 40 years. I know how to do classical programming. When I first started learning about quantum computing, I'd read about something, and I'd learn about it. And it would feel so good I'd wake up next morning and realize those are completely wrong, and I'd have to go back [and learn about it].

Because there are these kinds of things that do make sense from a quantum mechanics perspective, but from a traditional binary or digital computing [standpoint], it's just weird. So, we [at IBM] do believe that this is going to be very possibly the most important computing technology of the century, and that's why people should care.

Why focus on the qubit so much in your book?

Sutor: When I was writing Dancing with Qubits, a friend of mine asked me whether I was going to write a very high-level, fluffy and incorrect book, or a really detailed complicated-yet-impenetrable book. I told him: neither.

What I also discovered was that a lot of other books [on quantum computing] had some pretty significant prerequisites of what they expected you already to know or go somewhere somehow find out. And, in fact, one of the things I found with quantum computing was you had to jump all over the place to find this information; and I have a Ph.D. in theoretical mathematics, so I have a reasonably good background.

I committed to writing a book that, yes, included some math, but I lead readers through it very carefully -- almost conversationally. And I'd like to imagine I was standing next to you right now at a whiteboard, or we were having coffee, and just discussing [quantum computing] systematically. We would talk about how the pieces come together, why they're important and just kind of build on [the concepts] level by level.

Then, by the time you were done with the book you would know what a qubit really is. You would know the math for [a quantum computing qubit] and you would be able to reason about it.

What do you hope readers gain from your book?

Sutor: With this book, people can start reading [and] they can get enough of the background, and then they can learn more about what's really going on [with quantum computing] to whatever level is interesting or important. I hope that they have a comfortable learning experience and feel confident and empowered to go on and learn more.