Is Quantum Tech All Hype?

In spring 2019, a mysterious account called Quantum Bullshit Detector emerged on Twitter, which started commenting on all kinds of news in the quantum scene. Announcements of breakthroughs, industry forecasts and lectures by top-tier universities all received one word of commentary: “Bullshit.”

Despite its cheeky nature, the account didn’t seem to be purely a joke. Experts and journalists alike speculated on who was behind it. The poster seemed to be someone who was very familiar with the jargon, which meant it was almost definitely someone from inside the community. As people involved with quantum technology are almost exclusively scientists who, per their job description, love debating ideas, the account’s laconic style and unwillingness to debate made this mystery even more puzzling.

After several months of voicing opinions in its unapologetic style,computer science professor David J. Bruton, alias Scott Aaronson, revealed himself as the brain behind the bullshit detector. The quantum community, while supportive of the account’s underlying principle, didn’t like the fact that it was a one-man show, however well-executed. Thus, the Democratic Quantum Bullshit Detector was launched. This account determined whether something was “Bullshit” or “Not Bullshit”via Twitter polls. 

Somewhat surprisingly, a budding quantum company acquired the original detector in early 2021. Soon after, it shut down operations. The democratic version of the bullshit detector, while still active, so far has failed to gain as much traction as the original one.

Dismissing an entire promising technological frontier that has been built on solid science for decades as mere hype does seem like overkill. Still, with the amount of public and private investments in quantum tech soaring in recent years, it makes sense to give cautionary voices room to be heard. Though unlikely, it’s not inconceivable that overblown greed and groupthink is making policymakers and private investors write easy checks without doing their due diligence. So, is quantum all hype, or are we right to believe in its transformative potential?

Are Researchers Overpromising? Are Governments Overinvesting?

News abounds that quantum companies areraising many millions of dollars or that one of them has made another breakthrough. To people without a background in quantum physics or a related field, this might seem like a giant scam, ready to implode at any moment. The promises that the industry gives — from developing better drugs to building better software for finance to revolutionizing cryptography — may seem too far-fetched and all-over-the-place to be true.

However far-fetched, if some key issues with quantum computers get sorted out, all these promises will come true. But those key issues are what’s making the game complicated.

For a quantum computer to be usable, it needs around a million qubits. A qubit is a quantum unit of storage, analogous to a bit in a classical computer. The big problem is that qubits are highly unstable and error-prone. At the time of writing this article, the record stands at a qubit that stored its data for nine seconds, and even getting a few hundred error-free qubits is a huge feat.

Recent developments do look encouraging, however. These include, but aren’t limited to, using nanostructures for quantum electronics, mathematically proving that quantum AI works, and building the largest quantum computer to date. If progress continues like it has the past few years, we’ll be well in the era of quantum computing by the time this decade is over. 

I do understand how outlandish the predictions about quantum computing can seem to someone who is new to the domain. Then again, in my personal experience, explaining advanced physics to a layperson always makes me feel a little like I’m a magician trying to instruct a novice. Despite how insane physics theories often sound, however, they’re often the foundation that today’s technology relies on. 

To give you an example, you wouldn’t be able to read this article on your device if it weren’t for semiconductor physics. The building blocks of computers and most other electronic devices are transistors. They act as on-off switches that encode all of a computer’s data. For example, the letter A translates to 01000001 in binary code; that’s eight transistors where zero means switched off and one means switched on. Transistors, in turn, are made of semiconductors. And if physicists hadn’t started obsessing about semiconductors in the middle of the last century, we would be living in a very different age today — one without computers and other electronic devices.

There’s no question that the promises, the large sums of money at stake, and government endorsements are putting the field under pressure it’s never seen before. My prediction, however, is that it will thrive under this pressure rather than crumble.

Quantum Is Already Yielding Results

The reason for my optimism is simple: Quantum technology is already in use! For example, positron emission tomography is a standard medical procedure to scan regions of the human body. The principle is that a small amount of a radioactive substance is given intravenously, and its radioactive decay is subsequently detected. 

In this radioactive decay, a positron (hence the name) collides with an electron. During the collision, these two particles become two entangled photons. This may sound very fancy, but it just means that two particles that make light are linked to one another on a quantum level. The photons, and their entanglement, are finally captured in a detector. Because we know that they’re emitted at 180 degrees from one another at the collision site, we can calculate where this site was from the location of the photons in the detector. The sum of all matching photons, back-tracked to their collision site, then becomes the image of a body part.

This is not a recent breakthrough, though: Positron emission tomography has been in use since the 1970s. Still, it uses quantum tech!

A more recent product of quantum tech is random numbers. Although using a futuristic supercomputer to make, of all things, a heap of totally random numbers might sound silly, this principle lies at the heart of a lot of modern cryptography and statistical simulations. Quantum computers are very good at making random numbers because the measurement of a quantum state, as it occurs in quantum computers,is inherently random.

Swiss company ID Quantique sells the random numbers it has generated on quantum computers, and it’s one of the few quantum companies that is currently profitable. For comparison, IonQ, the first publicly traded firm that focuses solely on quantum computing, doesn’t expect significant revenue or profit until 2024 or 2025. This is indicative of how early in its development quantum technology still is.

Positron emission tomography and random numbers are just two examples, though. We can expect dozens more to appear over the next decade due to advances in building more and better qubits, making quantum software, and the sheer amount of money and talent that is gravitating towards quantum and making these breakthroughs possible. They prove, however, that quantum technology is already in deployment and making profits.

Link：https://builtin.com/software-engineering-perspectives/quantum-tech-hype