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Will Quantum Computers Really Arrive? At Least, I Don't Think They'll Be Mainstream in My Working Lifetime

Lately, I keep seeing articles saying “After AI, it’s quantum computing!”

I get the excitement. Quantum computing as a technology is genuinely fascinating. Sci-fi-sounding ideas are actually advancing on solid physics.

But looking at it calmly as an engineer, when someone asks “Is this something we’ll be using normally while we’re still in the workforce?” — I have serious doubts.

At the very least, a future where quantum computers sit in offices, run inside smartphones, or get used routinely by ordinary companies seems pretty far away.

Today I want to lay out the reasons, including the perspective of someone who once studied physics.

So What Is a Quantum Computer Actually Doing?

A regular computer calculates using “0” or “1.”

That hasn’t changed for decades. AI, cloud, smartphones — they all come down to this.

A quantum computer, on the other hand, uses a property of quantum mechanics called “superposition.”

Roughly speaking, it computes using states that are:

A common analogy:

By using lots of these “ambiguous spinning states” together, you can theoretically achieve enormous speed for certain problems.

This part really is exciting.

But Reality Is Pretty Harsh

Once you actually look into it, today’s quantum computers are closer to “experimental devices from the future.”

The tough parts are roughly these.

① Way Too Sensitive to Noise

This is the biggest problem.

Quantum states are extremely fragile.

Temperature changes, vibration, electromagnetic interference — any small disturbance crashes the calculation.

In our coin analogy, it’s like blowing gently from the side at a spinning coin and watching it fall over.

So you can’t treat them roughly like ordinary computers.

② The Cooling System Is Insane

The mainstream superconducting approach requires cooling to near absolute zero.

Absolute zero is roughly minus 273°C.

And the cooling system is much larger than the actual computer.

When you see quantum computers in the news, that gold chandelier-looking device that seems to be the “main unit” — most of it is actually the cooling apparatus.

My honest reaction when I saw that: “Yeah, this is data-center-only…”

A future where this fits inside a laptop is not on the current trajectory.

③ Error Correction Is Basically Hell

Quantum computers produce so many errors that “quantum error correction” is mandatory.

The cost of that is staggering.

In practice, you need:

Theory suggests that stably running genuinely useful computations requires on the order of millions of qubits.

Today we’re still in the hundreds-to-thousands range.

Progress is real, of course. But the idea that it will go mainstream at the same speed as the current AI boom — that’s a very different story.

④ It’s Not a Universal Speedup

This is probably the most misunderstood point.

A quantum computer is not a “magic machine that makes everything faster.”

It’s good at:

Conversely, for:

regular CPUs and GPUs are overwhelmingly more efficient.

So rather than “quantum computers will replace everything,” I think the position will be more like a special-forces unit alongside supercomputers.

⑤ Severe Talent Shortage

This one is big too.

Quantum computing requires:

All of them.

The talent bar is abnormally high.

It’s not really an extension of being an ordinary IT engineer — it’s closer to physics research.

So this isn’t “software engineer shortage.” It’s a different scale of shortage entirely.

AI and Quantum Are Going in Different Evolutionary Directions

AI exploded as an extension of existing GPUs and cloud infrastructure.

That’s why it spread so fast.

But quantum computing is different from the physical layer up.

This isn’t a “new CPU.” It’s trying to build the computer itself out of different physical laws.

The difficulty is on another level.

That Said, It’s Not a Dreamless Story

To be clear, I’m not saying “quantum computers are meaningless.”

For fields like:

they will probably become genuinely important.

But for someone like me — an ordinary enterprise-systems engineer — I don’t really see a future where “quantum computer skills become mandatory starting next year!” turns into reality.

Summary

Quantum computing is fascinating as a future technology, for sure.

But looking at the present:

The problems are stacked high.

So personally, rather than “After AI, it’s quantum!”, my position is closer to “For a while longer, it’s still a high-end experimental device in research labs.”

That said, there’s one thing I want to emphasize.

Things that people thought were “absolutely impossible” have actually come this far.

I studied particle physics in school and took quantum mechanics. Back then, I think the idea of quantum computation existed as theory — Feynman (the physicist familiar from textbooks) reportedly proposed it.

But “actually running it as a working computer” was something I never heard discussed in my circle. It was strictly theoretical.

And now, companies like:

are actually building real machines.

Of course, huge walls remain before practical deployment. But conversely, the fact that humans are controlling quantum states well enough to run them as a calculator — that alone puts us in genuinely abnormal territory as a species.

So I’m not trying to hype “it’s coming soon.” But in the sense of “pulling something that was purely a dream out into physical reality,” it’s already a historically significant technology, I think.