Quantum Bootcamp: From Zero to Quantum in Our Spare Time, Part I

In celebration of World Quantum Day, the Department of Chemistry inaugurates a new student-written column in which two undergraduates describe their initiation into the strange and complex world of quantum science. Earlier this year, Ethan Wang and his friend Wonju Lee met chemistry Postdoc Benjamin Lienhard at an on-campus forum. Lienhard’s invitation to follow up on their interest with a one-year bootcamp in quantum computing, starting from scratch (or close to it), was quickly accepted. Out of that tutorial comes this, our first Quantum Bootcamp column, in which Wang lays out the plan and hopes for the best.

I’d like to describe the journey of two college freshmen—myself, an Economics major; and Wonju, an ECE major—as we try to acquire a solid basis in classical and quantum physics with little prior training. Why would we do this? So we can approach quantum computing from a research perspective.

Of course, quantum computing is no easy task. Discussions surrounding the field often melt into buzzword soup and meaningless jargon, especially for people not as well-acquainted with every technical facet of the subject. We hope this series of articles will provide some sort of roadmap on how anyone can approach the subject—and offer confirmation that, yes, it really is a difficult puzzle.

At a Wintersession workshop in January, Wonju and I met Benjamin Lienhard, who gave a thorough primer on quantum computing to a small audience eager to learn about it. Benjamin is a postdoctoral research fellow in the Rabitz Group at the Department of Chemistry and in the Türeci Group in the Department of Electrical and Computer Engineering. He is studying how to efficiently control and readout quantum information processors. After a few hours of diving into an introduction on the subject, Benjamin offered us the opportunity for a more in-depth experience with quantum computing, initially with the idea of pursuing some kind of research.

Being amply fascinated by the topic, we both accepted Benjamin’s offer. But we quickly realized that we were too technically inexperienced to dive straight into research. We do not have the proper intuition or knowledge to comprehend what we are looking for, or at, much less make meaningful contributions to the field.

So, we decided the best course of action would be a sort of quantum and physics bootcamp. We would, over the duration of about a year, run through a crash course on the fundamental classical and quantum mechanics we need to know in order to be technically proficient enough to engage in research by the end of the process. Yes, we know it’s a tall order.

The plan is to start with theoretical physicist Leonard Susskind’s bestselling book, The Theoretical Minimum (published in 2014) as a sort of “textbook” to our progress. We plan to read two chapters a week and then meet as a group to discuss any questions or to talk about a related topic.

Given this new context with which to interpret the subject of quantum computing, we quickly got a glimpse into just how technical and physics-based the whole subject is.

As we went through the most fundamental ideas behind classical mechanics, Benjamin would point out certain concepts that are relevant to quantum mechanics/computing. Quite often the most fundamental concepts in describing classical mechanics were themselves also fundamental to quantum, such as the Hamiltonian and modeling the equations of motion under the principle of least action.

We’ll get a little more into this next time. Suffice it to say that there are crucial tenets of quantum that find their origins in classical mechanics; they make the latter invaluable in understanding the former. What we realized more and more is that the tools used in quantum are themselves adapted in some way from classical mechanics. That seems only natural after all, but it is like learning an alphabet mostly shared by two languages—say, English and Spanish. We still need to learn the meanings of new words and all the accents, but the letters are the same.

By this point we are a good few weeks in. We’ve gone through the first Susskind book, and now we are working through the one on quantum mechanics, Quantum Mechanics: The Theoretical Minimum (published in 2015).

I think the main way we have changed our perspectives is coming to appreciate just how many different aspects go into quantum computing as a subject, and especially how close it is to physics in general. I entered this topic with the impression that it was more related to theoretical computer science. While there is plenty of that at the higher levels, when you really explore the quantum aspect of it, much of it really is just physics at its most fundamental level.

In our next column, we’ll jump right into the thick of it by sharing a few of the most interesting and relevant insights from classical mechanics. Then, we’ll go directly into quantum mechanics and its applications to computing.

Thanks for reading.

Look for our next column during the first week of May.