A coworker of mine, who happened to be another cohost user, told me today that I don’t update my blog enough, and that’s true.¹ I’ve really just not updated this blog in eons. Not for a lack of trying, but because I’m amazing at drafting stuff up and horrible at finishing anything—I need to just get more comfortable making lower-effort posts if this blog is about to be sustainable. (Would Douglass Natleson still be writing Nanoscale Views after all this time if he made all of the posts several-thousand words long? Probably not.)

Anyways, I present to you a rambling post about how feel about the whole international year of quantum science and technology.

In any case, if you’re in physics or some adjacent field—probably either computer science, electrical engineering, or mathematics—you’ve probably heard that 2025 will be the “year of quantum science and technology.” Soon, it will be 100 years since the discovery of matrix mechanics, the first consistent formulation of quantum mechanics, which was laid out in three papers by Heisenberg, Born, and Jordan. While quantum mechanics existed before then, it was essentially a piecemeal bunch of corrections to classical mechanics—Planck’s original paper on black-body radiation basically suggested the formula ad hoc, while Bohr’s paper on the hydrogen atom was basically concerned with deriving the curve emission spectra of hydrogen atoms—and no truly unified way of doing quantum mechanics existed until then. (Some mathematicians think that quantum mechanics is not a fully-realized theory since it’s not all up to their standards of mathematical rigor—they are unburdened by physics.)

Plenty of time has passed since then, and quantum mechanics—split between condensed matter, atomic/molecular/optical, high-energy, and nuclear physics—has advanced significantly from its humble roots. The advent of quantum mechanics has brought about many changes in science, and the fields derived from quantum mechanics are not only responsible for a whole host of the modern technologies we have—from amazing, wonderful things like lasers and transistors to the utterly horrific, such as atomic bombs—but indeed a great period of intellectual development. Because of quantum mechanics, we understand far more about tiny, tiny objects.

Yet all of these fields are separate, bifurcated. The average condensed matter physicist sees very little of atomic physics or nuclear physics, despite much of the theory being the same, despite all of these fields utilizing similar formalisms, they have almost irrecoverably drifted away from one another: there’s just too much to learn in each respective field for the average physicist to be expected to learn everything. Now that most of the easy problems have been solved, physicists need to get far deeper into different topics. Despite this, a new field of physics has emerged: quantum science and technology.

Well, actually, calling this a new field would is a bit hyperbolic—I would call it the union between condensed matter and atomic physics (and computer science for quantum computing), since the vast majority of research comes from those fields. Quantum science and technology (or just “quantum”) is a bit like nanotechnology insofar as it’s a grouping for interdisciplinary research on similar topics. There’s a lot of great research to talk about in this realm—of particular interest for me is the work in quantum materials and many-body physics, both theoretical and experimental—but the field is incredibly broad.

Of course, there are still differences between atomic and condensed matter physics, and physicists have been dipping their toes between both fields for a while now—for example, Elliot Lieb, one of the GOATs in modern theoretical and mathematical physics, has done extensive work on condensed matter physics and a fair amount of quantum optics (see for example the Dicke model)—but I think quantum science could be a genuine beginning at reconnecting various fields of physics. Maybe I’m being unduly optimistic but, as far as basic research goes, I hope to see the current wave of cross-pollination, which quantum science has enabled, continue.

Two days ago, ironically, quantum computing stocks crashed. Mark Zuckerberg and the CEO of NVidia both said something negative about quantum computers, which caused a bunch of investors to dump their stock in Rigetti, IonQ, and the like.

I’ve railed against the quantum computing industry for their exorbitant claims in the past, but it’s clear to me that this crash was a confluence of two things—the deep stupidity of the average investor and the market’s hostility towards long-term R&D without any real returns. Quantum computers have been an intense challenge to develop in no small part due to the fact that they’re still in the fundamental research stages—like nuclear fusion power, they were just a decade away in the late 1990s to early 2000s, and today quantum computers remain just a decade away. Despite every quantum computing company saying that they have created a scalable qubit or computer, reality is not quite that simple, and the coherent states required to do quantum computing are quite fragile.

The average technology investor seems to have simply lost hope in quantum computing, likely because of generative AI sucking up all of the air in the tech industry recently. Unlike quantum computers, a machine-learning platform can be up and running within a few months—you don’t need to make software engineers learn an entirely new way of thinking about programming, and you don’t need to hire a bunch of egghead physicists to do R&D. All you need to do for AI is just get an API token and get cracking.

Perhaps more salient to me, though, is the way that quantum computers are spoken of by businessmen and science “communicators” (mostly Michio Kaku). Quantum computers aren’t really machines to these people, but a new form of Charles Babbage’s theoretical computer in his Bridgewater Treatise, a sort of memory in the atmosphere. In essence, they’re an endgoal, a shorthand for near-infinite knowledge—a machine that can break all encryption, predict the stock market, and discover all possible molecules before we understand their function. No matter if we get a practical quantum computer or not, the people funding quantum computing will likely be disappointed in the results. At the end of the day, quantum computers could wind up just being like Intel Itanium processors, with incredibly theoretical speeds and lackluster real performance.

Of course, I haven’t lost hope in quantum technologies, mostly because of the fact that they’ve existed for ages. SQUIDs, superconducting magnetic field sensors, have been around since the 1960s, and have been used in MRI machines since the 1970s; and likewise Josephson junction voltage standards have been the standard for electrometrology since the 1980s; superconducting photodetectors have been around forever. Lasers have been around since the 1960s, and have been used in telecommunication networks, surgeries, and more. Likewise, atomic clocks in some way, shape, or form have been the basis of modern, high-precision timekeeping since the 1950s. Quantum technologies have existed for a while now—chances are, they’ll remain largely inaccessible to the average person, as they’ve always been.

I have attached below my original cohost post about quantum technologies. My opinion, as you’ve probably read, is far less sectarian than it used to be, but I still maintain that the quantum computing industry sucks.

My original post railing against quantum computing.

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The worst part about being a physicist right now is all the hype around quantum tech, because the suits have seen it fit to just call it “quantum”—and somehow it applies equally between quantum optics, quantum sensors, and quantum computers.

“Yeah, I think ‘quantum’ will win the Nobel prize this year”—what the fuck does that mean? What, are condensed matter, atomic, nuclear, and particle physics suddenly not “quantum” enough?"}}

I can’t stress this enough, quantum technology is not a field of study all on its own, but instead the application of many disparate fields all at once—superconducting qubits are a product of condensed matter physics, and rubidium magnetometers are a product of quantum optics and atomic physics. I think boiling down all these bits of physics into just “quantum” is absurd.

And no, I’m not missing the forest for the trees—I’m just saying that the forest has more than one type of tree, and there are things in the forest that aren’t trees.

Moreover, if the quantum tech hype train keeps moving along like it is, I think quantum computer funding will dry up in the next 5–10 years, but quantum sensors might be on the chopping block too. I think the short-term gain of hyping up quantum computers will ultimately backfire if we don’t emphasize how much most technologies aren’t ready for the public; contemporary quantum computers don’t have qubits reliable or robust enough to do any really meaningful work, and most quantum sensors, aside from SQUIDs—which have been around since the 1960s—aren’t ready to be put in a little package to do any real sensing work. We have 10 billion quantum computing startups that are somehow all the first to make a "scalable" quantum computer—about half of those startups call themselves the first to do quantum computing as a service.

Sooner or later, if the current situation continues, I have a feeling we’re going to see something like the Schön scandal all over again—there’s too much hype in the field to not let some really bad science fly through the door. Chances are it’ll come from a smaller, less well funded startup that’s looking to get more funding.

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