How to finally get a grasp on quantum computing

Quantum computing seems to pop up in the news pretty often these days. You’ve probably seen quantum chips gracing your feeds and their odd, steampunk-ish cooling systems in the pages of magazines and newspapers. Politicians and business leaders are peppering their announcements with the word “quantum” more frequently, too. If you’re feeling a little confused about it all, it’s a good year for a New Year’s resolution to finally figure out what quantum computing is all about.

This is an ambitious goal, and the timing certainly makes sense. The quantum computing industry has seen many scientific achievements this past year, and the field is now worth more than $1 billion – a figure projected to double within the next two years. But wherever there is money and growing interest, there is also bound to be lots of hype.

Plenty of questions remain about when or how a quantum computer may be able to outdo conventional computers. Mathematicians and theorists may be able to answer some of them, but our best bet might be to just build better quantum computers and, well, mess around with them. Even that isn’t easy, though: there’s no broad consensus on how to build a better quantum computer.

Making matters worse for the quantum-computing-curious, quantum mechanics is genuinely hard to grasp. Physicists still disagree on how exactly we should make sense of the strange quantum phenomena like superpositions or entanglement. Yet it is exactly these odd properties that are the crucial ingredients of quantum computing.

If that sounds overwhelming, you are not alone. But I believe these barriers are not insurmountable. Just look to the kids.

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I used to be a high school teacher and there were always a few students in my classes that would hang back after lectures to ask me surprisingly technical questions about quantum computing. They were curious, and that was sufficient for them to learn enough to ask great questions, even when their mastery of mathematics and physics was not exceptionally advanced. One year, a student approached me after completing an online quantum computing course over the summer just for fun, and they effectively knew more about writing quantum computer code than I did! We spent the following year working through lessons that I would have otherwise only taught to college students.

A few months ago, I found another quantum-knowledge-seeker who was starting young. A 9-year-old YouTuber called Kai co-hosts a podcast called The Quantum Kid, in which he asks questions about quantum computers to some of the world’s leading experts while more than 88,000 subscribers watch and learn alongside him.

Kai’s co-host is his mother, Katia Moskvitch, a physicist with a long career in science writing. Moskvitch works at Quantum Machines, a company that builds conventional computing devices that help quantum computers actually work, so she is no stranger to the industry. Kai brings lots of curiosity and excitement to the podcast, and he has the great privilege to pose questions to people who have played huge roles in shaping our modern ideas about quantum computing.

Peter Shor formulated the most famous quantum computing algorithm, and he joined the podcast to talk to Kai about what quantum computers may have to do with improving sustainability and combating climate change. Nobel laureate and former US Secretary of Energy Steven Chu makes an appearance in the same episode. Computer scientist Scott Aaronson, an influential expert on quantum computing algorithms, chats with Kai about whether quantum mechanics allows time travel and whether even such a fanciful idea may, in theory, have some ties to quantum computing. John Preskill, another physicist whose work impacted how we measure quantum computers’ success today, comes on to chat about quantum computing and robotics alongside roboticist Ken Goldberg.

To be clear, The Quantum Kid will not necessarily provide you with rigorous mathematical knowledge about quantum computing, but it’s a great start and a charming way to hear from some of the field’s biggest names. Most episodes do touch on the basics of quantum mechanics, like superposition states or the Heisenberg uncertainty principle, but to truly understand them in detail, I would recommend reading further, perhaps in a publication like New Scientist.

The value and charm of The Quantum Kid lie in the fact that Kai asks exactly the questions you may have if all you know about quantum computers is that they’re somehow special and potentially very powerful. In other words, if you have resolved to finally understand quantum computers but feel like you know nothing, Kai is here to tell you to be curious and ask questions anyway. (I’d also be happy to help guide you through the thorny world of everything quantum.)

Can quantum computers help us explore space or travel to the past? Can they help us make smarter robots and fight climate change? Will we ever use them to make airplane navigation better or create materials that currently seem like a fantasy? The answers to these questions are complex and nuanced and full of uncertainty. Explaining that to an excited 9-year-old requires clarity and kindness, something that the viewers of The Quantum Kid also benefit from. I loved hearing Peter Shor repeatedly say that existing quantum computers are, by and large, not powerful enough to change the world without completely dampening Kai’s enthusiasm.

In the first episode, physicists Renato Renner tells Kai that “you will grow up with a new machine that can potentially do new things, and you have to think about how to use it,” which sets up an optimistic, future-facing tone for the podcast that is echoed by many of its guests.

This is also just the right attitude to take into any quantum learning project you may embark on this year – a mix of Kai’s enthusiasm, imagination and curiosity and his guests’ grounded and nuanced expertise. Quantum computing is complicated and full of caveats, but that speaks to the utter newness of it, and what could be more exciting? And if a 9-year-old can handle a taste of that, you can certainly give it a shot too.