'Quantum Computing Has a Hype Problem' (technologyreview.com) 48
"A reputed expert in the quantum computing field puts it in black and white: as of today, quantum computing is a paper tiger, and nobody knows when (if ever) it will become commercially practical," writes Slashdot reader OneHundredAndTen. "In the meantime, the hype continues."
In an opinion piece for MIT Technology Review, Sankar Das Sarma, a "pro-quantum-computing" physicist that's "published more than 100 technical papers on the subject," says he's disturbed by some of the quantum computing hype he sees today, "particularly when it comes to claims about how it will be commercialized." Here's an excerpt from his article: Established applications for quantum computers do exist. The best known is Peter Shor's 1994 theoretical demonstration that a quantum computer can solve the hard problem of finding the prime factors of large numbers exponentially faster than all classical schemes. Prime factorization is at the heart of breaking the universally used RSA-based cryptography, so Shor's factorization scheme immediately attracted the attention of national governments everywhere, leading to considerable quantum-computing research funding. The only problem? Actually making a quantum computer that could do it. That depends on implementing an idea pioneered by Shor and others called quantum-error correction, a process to compensate for the fact that quantum states disappear quickly because of environmental noise (a phenomenon called "decoherence"). In 1994, scientists thought that such error correction would be easy because physics allows it. But in practice, it is extremely difficult.
The most advanced quantum computers today have dozens of decohering (or "noisy") physical qubits. Building a quantum computer that could crack RSA codes out of such components would require many millions if not billions of qubits. Only tens of thousands of these would be used for computation -- so-called logical qubits; the rest would be needed for error correction, compensating for decoherence. The qubit systems we have today are a tremendous scientific achievement, but they take us no closer to having a quantum computer that can solve a problem that anybody cares about. It is akin to trying to make today's best smartphones using vacuum tubes from the early 1900s. You can put 100 tubes together and establish the principle that if you could somehow get 10 billion of them to work together in a coherent, seamless manner, you could achieve all kinds of miracles. What, however, is missing is the breakthrough of integrated circuits and CPUs leading to smartphones -- it took 60 years of very difficult engineering to go from the invention of transistors to the smartphone with no new physics involved in the process.
In an opinion piece for MIT Technology Review, Sankar Das Sarma, a "pro-quantum-computing" physicist that's "published more than 100 technical papers on the subject," says he's disturbed by some of the quantum computing hype he sees today, "particularly when it comes to claims about how it will be commercialized." Here's an excerpt from his article: Established applications for quantum computers do exist. The best known is Peter Shor's 1994 theoretical demonstration that a quantum computer can solve the hard problem of finding the prime factors of large numbers exponentially faster than all classical schemes. Prime factorization is at the heart of breaking the universally used RSA-based cryptography, so Shor's factorization scheme immediately attracted the attention of national governments everywhere, leading to considerable quantum-computing research funding. The only problem? Actually making a quantum computer that could do it. That depends on implementing an idea pioneered by Shor and others called quantum-error correction, a process to compensate for the fact that quantum states disappear quickly because of environmental noise (a phenomenon called "decoherence"). In 1994, scientists thought that such error correction would be easy because physics allows it. But in practice, it is extremely difficult.
The most advanced quantum computers today have dozens of decohering (or "noisy") physical qubits. Building a quantum computer that could crack RSA codes out of such components would require many millions if not billions of qubits. Only tens of thousands of these would be used for computation -- so-called logical qubits; the rest would be needed for error correction, compensating for decoherence. The qubit systems we have today are a tremendous scientific achievement, but they take us no closer to having a quantum computer that can solve a problem that anybody cares about. It is akin to trying to make today's best smartphones using vacuum tubes from the early 1900s. You can put 100 tubes together and establish the principle that if you could somehow get 10 billion of them to work together in a coherent, seamless manner, you could achieve all kinds of miracles. What, however, is missing is the breakthrough of integrated circuits and CPUs leading to smartphones -- it took 60 years of very difficult engineering to go from the invention of transistors to the smartphone with no new physics involved in the process.
It is a money problem. (Score:1)
Let's face it, government and many investors generally don't have the best judgement.
Re: It is a money problem. (Score:1)
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Relevant xkcd:
https://xkcd.com/1838/ [xkcd.com]
https://xkcd.com/1897/ [xkcd.com]
Schroedinger's tiger (Score:2)
quantum computing is a paper tiger, and nobody knows when (if ever) it will become commercially practical
I believe that would make it Schroedinger's tiger?
Blockchain (Score:2)
Wait 'til he finds out about blockchains and NFTs. Hooo boy.
Optical is the only way it will ever work (Score:2)
Photons maintain coherence crossing the entire universe, electrons can't compete.
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The inherent property of humour in general is quantum-like. You either get it or not. ;)
Go Memsistor and Fractal Memory!!! (Score:3)
I'm sticking to my guns (Score:2)
I'm not going to care about quantum computing until I can ssh on a machine that can do programmable quantum computing at a practical scale.
I'm excited people are looking into it. But personally, not gonna care for a while.
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I am in the same camp, minus the excitement. I had an actual expert explain things to me about 30 years ago. He was spot-on regarding the "progress" to be expected.
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> You should talk to your expert again. The QC world changed a lot in the last year.
Not sure how much an evaluation of these kinds of progress in QC change an evaluation of overall progress in QC
"... 2021 also saw the first experimental demonstration of fault-tolerant Bacon-Shor code in a single logical qubit of a trapped-ion system, i.e. a demonstration for which the addition of error correction is able to suppress more errors than is introduced by the overhead required to implement the error correction
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Indeed. All that was proven is that _theoretically_ error-correction can work. It may still blow up hardware size all out of proportion and make building it completely infeasible in practice, especially if you need, for example, do a complex calculation with 6k Qbits to break 2k RSA. The last number I saw was 50 effective Qbits after error correction, I think from IBM, and no statement of how the effort for correction scales with raising numbers of effective Qbits. Error correction has a tendency to scale a
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You should talk to your expert again. The QC world changed a lot in the last year. A lot of us who were ignoring it have realized we maybe can't safely do that any more.
It did not. Marketing got better (i.e. lies more convincing) but that is it. Incidentally, I am not ignoring what is happening (as a security expert that would be quite foolish), but I continue to be quite unimpressed. I think the longer this goes and the more advances are made, the worse the outlook for actually working and meaningful application is becoming. The last year was _no_ exception to that.
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I'm not going to care about quantum computing until I can ssh on a machine that can do programmable quantum computing at a practical scale.
I'm excited people are looking into it. But personally, not gonna care for a while.
I care.
I build crypto software and crypto security infrastructure for devices that are used by billions of people and need to last years, and in some cases decades. It's unlikely that practical quantum computers capable of breaking in-use asymmetric cryptography will appear in the next 5-10 years, but it's not only possible, the probability has significantly increased in the last year.
Until very recently, quantum computing was still in a state where error correction efficiency fell below the threshold
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I care... but not that much.
The biggest problem in crypto is just getting people to care at all - look at the sheer scale of data breaches where internal connections/databases are completely unprotected. Unfortunately, that often means purposely setting the bars as low as we can without scaring off users - for instance, better to have users encrypting using only 3DES than nothing at all. This is closely coupled to integrating low-level crypto (e.g., AES) into high-level libraries accessible to typical de
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I'm not concerned about the application layer. Applications are easy to update (relatively, not saying there aren't challenges, just that they're much, much easier to deal with). I'm concerned about system integrity, firmware signing, etc. The signing keys used for firmware for millions to billions of devices can't be changed, last for years to decades, and the low-level software on devices is the foundation for absolutely everything else done on them. Pwn the bootloader (or the ROM!) and the rest of the
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Yeah, I am not in the security business. I am in the optimization and high performance business. And I suppose I have the luxury to ignore quantum computing until it becomes clear it will eventually work.
At this point, my PhD is 15 years old and the people who were working on that "very exciting technology about to become practical" have not much to show for. It is likely I'll retire in 20 years and QC will still not be practical at that time.
What doesn't.... (Score:2)
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Quite true. Many people looking for meaning and game-changers, and quite a few willing to exploit that to make a dollar. Almost assures stagnation, because real progress is low and very rarely makes a larger step.
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The journey to running faster than sound starts with going for a quick jog around the park, right?
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The problem is a lot of key advantages either come all at once or not at all - blacksmithing was around for thousands of years, but without the key ingredients like the Bessemer process, it simply couldn't scale to the extent require for industrialization.
A solution for a narrow set of problems ... (Score:2)
It doesn't have to work to achieve the goal (Score:3)
Vacuum tube - ENIAC is a better analogy (Score:2)
Transistor -> smartphone is a bad analogy.
Smartphones are not efficient computing devices. That isn't their purpose and they use transistors very inefficiently. Further, transistors are second-generation computation elements. When the first transistor was invented, there are were already computers built out of tens of thousands of vacuum tubes.
A better comparison is the first vacuum tube to the first vacuum tube computer. Eniac had 19,000 vacuum tubes. That would be 1904 to 1940 or so depending on w
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The transistor was needed before lithographic miniaturisation was possible. Sure, computers worked with valves, but they were primitive as all hell.
Sankar Das Sarma is saying that, up against modern conventional computing, valve equivalent quantum computing just won't ever cut it. Ie: He expects it'll need a fundamental revolution, like the transistor was, first.
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An even better comparison would be from Babbage to an actual practical computer.
The incredibly slow (by today's standards) and failure prone tube based computers were already a huge advancement over Babbage's theoretical (since only parts of it were ever built) mechanical system.
As TFA pointed out, the things will need to be about 6 orders of magnitude larger to actually crack RSA.
Imagine a demo of early smartphone technology where if you combined "only" one million of them together they could make a phone
Not a problem. (Score:2)
It's only a problem for investors who think they are going to get huge sums of money out of it. It could eventually be a useful tool for certain problems. Maybe there will be a breakthrough in 40 years, who knows.
I don't see the problem here unless you're an investor.
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Put another way, don't worry about quantum computing cracking your keys. You'll be long dead by the time cracking your key will be cheap enough to be worth it, even if it's your bitcoin wallet.
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I disagree because that seems like it's one of the few applications of quantum computing. Also, being "worth it" is not an issue for governments.
I'm not a cat, but... (Score:2)
My opinion on quantum computing is (1/sqrt(2))( |great idea> + |empty hype> )
Every computer needs a janitor. (Score:2)
Building a quantum computer that could crack RSA codes out of such components would require many millions if not billions of qubits. Only tens of thousands of these would be used for computation -- so-called logical qubits; the rest would be needed for error correction, compensating for decoherence.
Brains and microglia. [youtu.be]
silicon qubits (Score:1)
The technical term (Score:2)
The technical term is "hype supremacy".
The real problem (Score:1)
Does this mean that quantum computing ... (Score:2)
It's not a hype problem - it's a results problem (Score:2)
Maybe one day they will. And that day, the price of storage will crash. Because the TLAs of the world will start crunching through their stored encrypted data to decrypt it and find the interesting stuff, freeing up a lot of storage for more productive uses. That'll be more-or-less current levels of storage equipment, not the storage that was relevant at the time the data was stored by the TLA.
May be away around quantum error corretion (Score:1)
Phys qubits / quantum volume / algorithmic qubits (Score:1)