9 ms·

The case against Google's claims of "quantum supremacy"

183 points by nsoonhui 2y ago

gnabgib 2y ago
Strange timing given the claim was in 2019, guess this post was generated because of Willow. Google claims to have proved its supremacy with new quantum computer (256 points, 1 year ago, 229 comments) https://news.ycombinator.com/item?id=36567839 https://news.ycombinator.com/item?id=36567839 Quantum computers: amazing progress, but probably false supremacy claims (126 points, 5 years ago, 73 comments) https://news.ycombinator.com/item?id=21167368 https://news.ycombinator.com/item?id=21167368 Google Achieves Quantum Supremacy. Is Encryption Safe? (38 points, 5 years ago, 21 comments) https://news.ycombinator.com/item?id=21100983 https://news.ycombinator.com/item?id=21100983 Google claims to have reached quantum supremacy (114 points, 5 years ago, 21 comments) https://news.ycombinator.com/item?id=21029598 https://news.ycombinator.com/item?id=21029598 Google Engineers Think This 72-Qubit Processor Can Achieve Quantum Supremacy (91 points, 7 years ago, 42 comments) https://news.ycombinator.com/item?id=16543876 https://news.ycombinator.com/item?id=16543876 Google plans to reach a Quantum Computing milestone before the year is out (147 points, 8 years ago, 49 comments) https://news.ycombinator.com/item?id=14171992 https://news.ycombinator.com/item?id=14171992
- bawolff 2y ago
  They added a paragraph at the end to address the new experiment. Still nothing really new here. I'm doubtful anything will convince the author short of shor's algorithm actually factoring large numbers.
  - thesz 2y ago
    https://eprint.iacr.org/2015/1018.pdf https://eprint.iacr.org/2015/1018.pdf As pointed out in [57], there has never been a genuine implementation of Shor’s algorithm. The only numbers ever to have been factored by that type of algorithm are 15 and 21, and those factorizations used a simplified version of Shor’s algorithm that requires one to know the factorization in advance.
    - adastra22 2y ago
      What’s the point of quoting this?
      - thesz 2y ago
        To me it was eye opening on how skewed is the presentation of these quantum computing number factoring advances. It is completely in line of the "The Case Against..."
        adastra22 2y ago
        No one is claiming number factoring advances. That would require much longer lived qubits entanglement than is currently possible. The tech is clearly advancing forward though.
        bawolff 2y ago
        That feels like a straw man. Nobody was claiming otherwise.
        rcxdude 2y ago
        It feels more like the time to develop the tech has outlived the hype cycle around the tech, perhaps moreso than usual. That doesn't mean it isn't going anywhere, just that it's still slow (and in fact, after the hype cycle, the average press release is more likely to be substantive than during it, even if it's still incremental). (From my reading/understanding of it, for a while there's been little point in trying to make a quantum computer big enough to do such work, because the individual parts would not work well enough for it to have any chance of success, while this result primarily is showing that they're now at the cusp of the predicted tipping point where the qubits have a low enough error rate that building a larger system out of them has a hope of working. That's the big news in google's recent announcement, not them pushing up the numbers in this somewhat contrived benchmark)
      - sampo 2y ago
        > What’s the point of quoting this? To remind us of the large difference between the public image vs the reality of quantum computing. Expectation: From the news, people are getting a feeling that quantum computing revolution is almost behind the corner, and current cryptosystems will soon become irrelevant. People are (here, in Hacker News) asking "is our society ready for this", "what could I do if I had this chip at home", "existing cryptography technology is in danger", "is it time to 100x key length on browsers". Reality: Using Shor's algorithm to factor 15 = 5×3 is still far beyond the reach of current quantum computers. We can factor 15 = 5×3 and even 21 = 7×3 if we cheat by eliminating those branches from the calculation that are not on the happy path the correct answer.
  - drpossum 2y ago
    A big part of all these discussions is "why should you trust any computational result you can't verify?"
    - evandrofisico 2y ago
      A big problem in science in general is reproducibility. There are thousands of papers being published every month with peer review, which prunes out the most obvious errors, but the whole system is built on trust. Very few labs around the world are tasked with testing results instead of trying to produce new science, and in this specific case, only google has access to the device being built and the computation tested by them impossible to verify with classic computers, unlike Shor's algorithm which is trivial to test with known primes.
    - bawolff 2y ago
      Because you can verify it part of the way there. The point is to ensure that researchers are actually doing what they think they are doing and not deluding themselves. Its not meant to prevent outright fraud.
    - deleted 2y ago
      [deleted]
- thesz 2y ago
  Yes, it contains "I) Update (Dec. 10): The Wind in the Willow"
- sampo 2y ago
  > Strange timing given the claim was in 2019 In 2024 Google used 67 quantum bits to solve the same/similar random circuit sampling benchmark, that they used 53 bits in 2019. The discussion from 2019 on what is the relevance (if any) of solving random circuit simulation problems, is equally valid today. Maybe in 2030 Google or someone will use 200 or 400 bits to solve an even bigger instance of the random circuit simulation benchmark problem, and then we get to have this same discussion once again.
deleted 2y ago
[deleted]
bigbacaloa 2y ago
When plate tectonics was first proposed the low quality of the original models of the underlying mechanism led many very good geophysicists and geologists to reject it or to express well founded skepticism of the model. They knew the details and subtleties and the original models didn't deal well with them the proposal was nonetheless correct grosso modo and with time more adequate models of the underlying mechanisms were proposed and a more nuanced view of the model came into place. Now it is considered well established. One should consider the possibility that Gil Kalai is a similar sort of skeptic making well founded objections to weak arguments, but that nonetheless in the long run the extraordinary claims will turn out to be more or less correct. It's true that those involved in plate tectonics didn't have Bitcoin to sell you, but they were looking for oil.
- KK7NIL 2y ago
  No theory can stand on steady ground without the critics checking its foundations. It's a shame we cast their role in the history of science in such a negative light, as if science was a game to be won or lost instead of a collective process where a clear path forward only appears in hindsight (only to be proven wrong again sometime later) . Oh yeah, and that anecdote you told about tectonic plates screams survivorship bias; that's the problem with anecdotes.
  - IshKebab 2y ago
    I think his point was essentially that it's possible to have technically correct nitpicks that are irrelevant. You see this all the time from naysayers.
    - Veen 2y ago
      You also see institutions and researchers exaggerating and confabulating all the time, so the sceptics are a useful corrective, especially if they happen to be right.
    - KK7NIL 2y ago
      I understood that. My point is that they aren't irrelevant, they help drive the new theory forward. Galileo's initial results could not predict many things that the old geo-centric models could predict for centuries. This is almost inevitable with a groundbreaking new framework, but the skeptics aren't wrong to point it out, it's up to the supporters to show it can do what old model can do and more, which Galileo was never quite able to show in his lifetime, if I recall correctly. Again, it's easy to look back and talk about how these "irrelevant nitpicks" of tectonic plates and helio-centrism were "wrong" or "irrelevant", but that's just not how science works, you don't get to skip over the details when you present a theory that undermines everything we know, that's just crackpot behavior.
gigel82 2y ago
[flagged]
- adastra22 2y ago
  What is the point of saying that?
  - gigel82 2y ago
    Because it's factually true, and everyone that works in this industry (and academia) knows it. They won't admit it publicly because they'd like to continue to get funded (just like the folks working on fusion). When you can obtain the same results by replacing the futuristic-looking "qubits" with lava lamps you know the BS is laid on thick over there...
- kevindamm 2y ago
  When vacuum tubes were only reliable until they burned out (which they did quite often [1], and sometimes in ways that were difficult to detect directly), they probably seemed quite useless for the amount being invested in them. Calculations had to be repeated often enough to rule out circuit errors, but repeated use is also what caused them to fail. The Selectron tube hardly became mature enough to be integrated (it had to be scaled down, and its intended use case ended up going with the competing Williams-Kilburn tube). Researchers could have abandoned tube designs for delay-line memory, or even called it quits and gone back to the abacus and slide rule. Decades before that, we had a solution for holding a few hundreds of bits (up to low thousands of bits) in drum memory [2]. This depended a lot on the quality and evenness of the ferromagnetic material, and on reads being timed correctly. Researchers could have called it impractical and gone back to pencil and paper, there weren't even really computing devices to use them yet. Sometimes it's good to keep persisting at a problem space despite the impracticality of the current tech. I'm sure you can point to tech that continued to be impractical, but it doesn't mean that will always be so. [1] https://historyofinformation.com/detail.php?id=692 https://historyofinformation.com/detail.php?id=692 [2] https://web.archive.org/web/20220414065240/http://cs-exhibitions.uni-klu.ac.at/index.php?id=222 https://web.archive.org/web/20220414065240/http://cs-exhibit...
GilKalai 2y ago
Hi everybody, my post summarizes an on-going 5-year research project and four papers about the 2019 Google experiment. The timing of the post was indeed related to Google's Willow announcement and the fantastic septillion assertion. It is not clear why Google added to the announcement of nice published results about quantum error correction a hyped undocumented fantastic claim. I think that our work on Google's 2019 experiment provides useful information for evaluating Google's scientific conduct.
- vitus 2y ago
  Hi! I am under the impression that you're one of the better-known skeptics of the practicality of QEC. And to my untrained eye, the recent QEC claim is the more interesting one of the two. (I am inclined to ignore the claims about quantum supremacy, especially when they're based on random circuit sampling which as you pointed out made assertions that were orders of magnitude off because nobody cares about this problem classically, and so there is not much research effort into finding better classical algorithms. And of course, there's a problem with efficient verification, as Aaronson mentions in his recent post.) I've seen a few comments of yours where you mentioned that this is indeed a nice result (predicated on the assumption that it's true) [0, 1]. I worry a bit that you're moving the goalposts with this blog post, even as I can't fault any of your skepticism. I work at Google, but not anywhere close to quantum computing, and I don't know any of the authors or anyone who works on this. But I'm in a space where I feel impacts of the push for post-quantum crypto (e.g. bloat in TLS handshakes) and have historically pooh-poohed the "store now, decrypt later" threat model that Google has adopted -- I have assumed that any realistic attacks are at a minimum decades away (if they ever come to fruition), and very little (if any) of the user data we process today will be relevant to a nation-state actor in, say, 30 years. If I take the Willow announcement at face value (in particular, the QEC claims), should I update my priors? In particular, how much further progress would need to be made for you to abandon your previously-stated skepticism about the general ability of QEC to continue to scale exponentially? I see a mention of one-in-a-thousand error rates on distance-7 codes which seems tantalizingly close to what's claimed by Willow, but I would like to hear your take. [0] https://gilkalai.wordpress.com/2024/08/21/five-perspectives-on-quantum-supremacy/#comment-99296 https://gilkalai.wordpress.com/2024/08/21/five-perspectives-... [1] https://quantumcomputing.stackexchange.com/questions/30197/#comment52553_30197 https://quantumcomputing.stackexchange.com/questions/30197/#...
r33b33 2y ago
Let's talk about things that actually matter - where to invest in post-quantum world? I'll keep this short. - Google’s Willow quantum chip significantly outpaces current supercomputers, solving tasks in minutes that would otherwise take billions of years. - Hypothesis: Accelerating advancements in tech and AI could lead to quantum supremacy arriving sooner than the 2030s, contrary to expert predictions. - Legacy banking systems, being centralized, could transition faster to post-quantum-safe encryption by freezing transfers, re-checking processes, and migrating to new protocols in a controlled manner. - Decentralized cryptocurrencies face bigger challenges:Hard forks are difficult to coordinate across a decentralized network. - Transitioning to quantum-safe algorithms could lead to longer transaction signatures and significantly higher fees, eroding trust in the system. - If quantum computers compromise current cryptography, tangible assets (e.g., real estate, stock indices) may retain more value compared to digital assets like crypto. Thoughts?
- vishnugupta 2y ago
  > Legacy banking systems, From what I know about banking world, though second hand, having been working in payment processing systems I can say with confidence that it’s not the compute that’s holding them back.
- GTP 2y ago
  > Google’s Willow quantum chip significantly outpaces current supercomputers, solving tasks in minutes that would otherwise take billions of years. This is the point that was disputed in the article, and you're instead taking it for granted.
- nightowl_games 2y ago
  Quantum computing only solves certain classes of tasks faster, not all tasks, not most tasks, only a tiny amount of tasks.
  - zeroonetwothree 2y ago
    Actually, Grover’s algorithm would speed up a wide range of tasks. Hardly a tiny amount.
NanoYohaneTSU 2y ago
All of this stuff is so fake. Quantum computing is a vaporware scam and I've been saying it for at least a decade at this point. Waste of time and money by VCs who wants government money forever.
- evandrofisico 2y ago
  Quantum computing seems to be in the same realm as nuclear fusion as a power source. My Quantum theory professor used to say that in the 1960's, when he was a physics student in the Soviet Union it was "the energy of the future, in 20 years everything will be powered by nuclear fusion". When i was an undergrad student 20 years ago I did hear that "soon, quantum computing will change the world", and yet here we are, every year someone builds a new machine but no one has yet to factorize that 21 = 7x3 in a general way.
  - kgwgk 2y ago
    Fusion is the energy of the future – and it always will be.
    - short_sells_poo 2y ago
      You could also say we are already using fusion power - via solar panels. We have a massive ball of plasma powered by fusion in the sky and we are harvesting the energy it creates at an ever growing scale. Whether we'll be able to replicate it profitably at small scale is a question.
      - fluoridation 2y ago
        Of course, by that definition all forms of power generation are fusion, more or less removed from the fusion reactor in question.
        zeroonetwothree 2y ago
        Some part of geothermal energy comes from gravity which could be argued is not related to fusion (even if the matter undergoing gravity was created in fusion)
RivieraKid 2y ago
What's the most significant useful application of quantum computing, in other words, why should we be excited about QC, how will it improve people's lives?
- kuschkufan 2y ago
  that one dude that has tried since forever to convince that one city to allow him to dig up that garbage dump for his lost bitcoin wallet password should be able to get the coins without digging then. oh and all other passwords/pass phrases/secrets might get broken too, if they're not yet based on quantum save algos.
- n4r9 2y ago
  If we extend the definition of "computing" slightly to include "coding and cryptography", then I find superdense coding quite exciting [0]. In a hypothetical quantum internet we could encode and transmit two classical bits in every qubit, which effectively doubles your bandwidth. There's also quantum key distribution [1]. In principle, quantum theory allows Alice and Bob to establish a shared private key which cannot be broken without breaking the laws of physics. You can chat privately with people secure in the knowledge that not even the NSA can possibly be listening. [0] https://en.wikipedia.org/wiki/Superdense_coding https://en.wikipedia.org/wiki/Superdense_coding [1] https://en.wikipedia.org/wiki/Quantum_key_distribution https://en.wikipedia.org/wiki/Quantum_key_distribution
  - qup 2y ago
    > You can chat privately with people secure in the knowledge that not even the NSA can possibly be listening. Well, from one possible attack vector, anyway. They can still point lasers at your windows.
  - fluoridation 2y ago
    >In a hypothetical quantum internet we could encode and transmit two classical bits in every qubit, which effectively doubles your bandwidth. Hmm... What exactly are you transmitting in such a scenario? What's the physical layer protocol? I.e. what are the wires made of and what flows through them?
gibsonalisha292 2y ago
[dead]
Jackosas 2y ago
[dead]

183 points by nsoonhui 2y ago

Strange timing given the claim was in 2019, guess this post was generated because of Willow. Google claims to have proved its supremacy with new quantum computer (256 points, 1 year ago, 229 comments) https://news.ycombinator.com/item?id=36567839 https://news.ycombinator.com/item?id=36567839 Quantum computers: amazing progress, but probably false supremacy claims (126 points, 5 years ago, 73 comments) https://news.ycombinator.com/item?id=21167368 https://news.ycombinator.com/item?id=21167368 Google Achieves Quantum Supremacy. Is Encryption Safe? (38 points, 5 years ago, 21 comments) https://news.ycombinator.com/item?id=21100983 https://news.ycombinator.com/item?id=21100983 Google claims to have reached quantum supremacy (114 points, 5 years ago, 21 comments) https://news.ycombinator.com/item?id=21029598 https://news.ycombinator.com/item?id=21029598 Google Engineers Think This 72-Qubit Processor Can Achieve Quantum Supremacy (91 points, 7 years ago, 42 comments) https://news.ycombinator.com/item?id=16543876 https://news.ycombinator.com/item?id=16543876 Google plans to reach a Quantum Computing milestone before the year is out (147 points, 8 years ago, 49 comments) https://news.ycombinator.com/item?id=14171992 https://news.ycombinator.com/item?id=14171992

bawolff 2y ago
They added a paragraph at the end to address the new experiment. Still nothing really new here. I'm doubtful anything will convince the author short of shor's algorithm actually factoring large numbers.
- thesz 2y ago
  https://eprint.iacr.org/2015/1018.pdf https://eprint.iacr.org/2015/1018.pdf As pointed out in [57], there has never been a genuine implementation of Shor’s algorithm. The only numbers ever to have been factored by that type of algorithm are 15 and 21, and those factorizations used a simplified version of Shor’s algorithm that requires one to know the factorization in advance.
  - adastra22 2y ago
    What’s the point of quoting this?
    - thesz 2y ago
      To me it was eye opening on how skewed is the presentation of these quantum computing number factoring advances. It is completely in line of the "The Case Against..."
      - adastra22 2y ago
        No one is claiming number factoring advances. That would require much longer lived qubits entanglement than is currently possible. The tech is clearly advancing forward though.
      - bawolff 2y ago
        That feels like a straw man. Nobody was claiming otherwise.
      - rcxdude 2y ago
        It feels more like the time to develop the tech has outlived the hype cycle around the tech, perhaps moreso than usual. That doesn't mean it isn't going anywhere, just that it's still slow (and in fact, after the hype cycle, the average press release is more likely to be substantive than during it, even if it's still incremental). (From my reading/understanding of it, for a while there's been little point in trying to make a quantum computer big enough to do such work, because the individual parts would not work well enough for it to have any chance of success, while this result primarily is showing that they're now at the cusp of the predicted tipping point where the qubits have a low enough error rate that building a larger system out of them has a hope of working. That's the big news in google's recent announcement, not them pushing up the numbers in this somewhat contrived benchmark)
    - sampo 2y ago
      > What’s the point of quoting this? To remind us of the large difference between the public image vs the reality of quantum computing. Expectation: From the news, people are getting a feeling that quantum computing revolution is almost behind the corner, and current cryptosystems will soon become irrelevant. People are (here, in Hacker News) asking "is our society ready for this", "what could I do if I had this chip at home", "existing cryptography technology is in danger", "is it time to 100x key length on browsers". Reality: Using Shor's algorithm to factor 15 = 5×3 is still far beyond the reach of current quantum computers. We can factor 15 = 5×3 and even 21 = 7×3 if we cheat by eliminating those branches from the calculation that are not on the happy path the correct answer.
- drpossum 2y ago
  A big part of all these discussions is "why should you trust any computational result you can't verify?"
  - evandrofisico 2y ago
    A big problem in science in general is reproducibility. There are thousands of papers being published every month with peer review, which prunes out the most obvious errors, but the whole system is built on trust. Very few labs around the world are tasked with testing results instead of trying to produce new science, and in this specific case, only google has access to the device being built and the computation tested by them impossible to verify with classic computers, unlike Shor's algorithm which is trivial to test with known primes.
  - bawolff 2y ago
    Because you can verify it part of the way there. The point is to ensure that researchers are actually doing what they think they are doing and not deluding themselves. Its not meant to prevent outright fraud.
  - deleted 2y ago
    [deleted]
thesz 2y ago
Yes, it contains "I) Update (Dec. 10): The Wind in the Willow"
sampo 2y ago
> Strange timing given the claim was in 2019 In 2024 Google used 67 quantum bits to solve the same/similar random circuit sampling benchmark, that they used 53 bits in 2019. The discussion from 2019 on what is the relevance (if any) of solving random circuit simulation problems, is equally valid today. Maybe in 2030 Google or someone will use 200 or 400 bits to solve an even bigger instance of the random circuit simulation benchmark problem, and then we get to have this same discussion once again.

deleted 2y ago

[deleted]

bigbacaloa 2y ago

When plate tectonics was first proposed the low quality of the original models of the underlying mechanism led many very good geophysicists and geologists to reject it or to express well founded skepticism of the model. They knew the details and subtleties and the original models didn't deal well with them the proposal was nonetheless correct grosso modo and with time more adequate models of the underlying mechanisms were proposed and a more nuanced view of the model came into place. Now it is considered well established. One should consider the possibility that Gil Kalai is a similar sort of skeptic making well founded objections to weak arguments, but that nonetheless in the long run the extraordinary claims will turn out to be more or less correct. It's true that those involved in plate tectonics didn't have Bitcoin to sell you, but they were looking for oil.

KK7NIL 2y ago
No theory can stand on steady ground without the critics checking its foundations. It's a shame we cast their role in the history of science in such a negative light, as if science was a game to be won or lost instead of a collective process where a clear path forward only appears in hindsight (only to be proven wrong again sometime later) . Oh yeah, and that anecdote you told about tectonic plates screams survivorship bias; that's the problem with anecdotes.
- IshKebab 2y ago
  I think his point was essentially that it's possible to have technically correct nitpicks that are irrelevant. You see this all the time from naysayers.
  - Veen 2y ago
    You also see institutions and researchers exaggerating and confabulating all the time, so the sceptics are a useful corrective, especially if they happen to be right.
  - KK7NIL 2y ago
    I understood that. My point is that they aren't irrelevant, they help drive the new theory forward. Galileo's initial results could not predict many things that the old geo-centric models could predict for centuries. This is almost inevitable with a groundbreaking new framework, but the skeptics aren't wrong to point it out, it's up to the supporters to show it can do what old model can do and more, which Galileo was never quite able to show in his lifetime, if I recall correctly. Again, it's easy to look back and talk about how these "irrelevant nitpicks" of tectonic plates and helio-centrism were "wrong" or "irrelevant", but that's just not how science works, you don't get to skip over the details when you present a theory that undermines everything we know, that's just crackpot behavior.

gigel82 2y ago

[flagged]

adastra22 2y ago
What is the point of saying that?
- gigel82 2y ago
  Because it's factually true, and everyone that works in this industry (and academia) knows it. They won't admit it publicly because they'd like to continue to get funded (just like the folks working on fusion). When you can obtain the same results by replacing the futuristic-looking "qubits" with lava lamps you know the BS is laid on thick over there...
kevindamm 2y ago
When vacuum tubes were only reliable until they burned out (which they did quite often [1], and sometimes in ways that were difficult to detect directly), they probably seemed quite useless for the amount being invested in them. Calculations had to be repeated often enough to rule out circuit errors, but repeated use is also what caused them to fail. The Selectron tube hardly became mature enough to be integrated (it had to be scaled down, and its intended use case ended up going with the competing Williams-Kilburn tube). Researchers could have abandoned tube designs for delay-line memory, or even called it quits and gone back to the abacus and slide rule. Decades before that, we had a solution for holding a few hundreds of bits (up to low thousands of bits) in drum memory [2]. This depended a lot on the quality and evenness of the ferromagnetic material, and on reads being timed correctly. Researchers could have called it impractical and gone back to pencil and paper, there weren't even really computing devices to use them yet. Sometimes it's good to keep persisting at a problem space despite the impracticality of the current tech. I'm sure you can point to tech that continued to be impractical, but it doesn't mean that will always be so. [1] https://historyofinformation.com/detail.php?id=692 https://historyofinformation.com/detail.php?id=692 [2] https://web.archive.org/web/20220414065240/http://cs-exhibitions.uni-klu.ac.at/index.php?id=222 https://web.archive.org/web/20220414065240/http://cs-exhibit...

GilKalai 2y ago

Hi everybody, my post summarizes an on-going 5-year research project and four papers about the 2019 Google experiment. The timing of the post was indeed related to Google's Willow announcement and the fantastic septillion assertion. It is not clear why Google added to the announcement of nice published results about quantum error correction a hyped undocumented fantastic claim. I think that our work on Google's 2019 experiment provides useful information for evaluating Google's scientific conduct.

vitus 2y ago
Hi! I am under the impression that you're one of the better-known skeptics of the practicality of QEC. And to my untrained eye, the recent QEC claim is the more interesting one of the two. (I am inclined to ignore the claims about quantum supremacy, especially when they're based on random circuit sampling which as you pointed out made assertions that were orders of magnitude off because nobody cares about this problem classically, and so there is not much research effort into finding better classical algorithms. And of course, there's a problem with efficient verification, as Aaronson mentions in his recent post.) I've seen a few comments of yours where you mentioned that this is indeed a nice result (predicated on the assumption that it's true) [0, 1]. I worry a bit that you're moving the goalposts with this blog post, even as I can't fault any of your skepticism. I work at Google, but not anywhere close to quantum computing, and I don't know any of the authors or anyone who works on this. But I'm in a space where I feel impacts of the push for post-quantum crypto (e.g. bloat in TLS handshakes) and have historically pooh-poohed the "store now, decrypt later" threat model that Google has adopted -- I have assumed that any realistic attacks are at a minimum decades away (if they ever come to fruition), and very little (if any) of the user data we process today will be relevant to a nation-state actor in, say, 30 years. If I take the Willow announcement at face value (in particular, the QEC claims), should I update my priors? In particular, how much further progress would need to be made for you to abandon your previously-stated skepticism about the general ability of QEC to continue to scale exponentially? I see a mention of one-in-a-thousand error rates on distance-7 codes which seems tantalizingly close to what's claimed by Willow, but I would like to hear your take. [0] https://gilkalai.wordpress.com/2024/08/21/five-perspectives-on-quantum-supremacy/#comment-99296 https://gilkalai.wordpress.com/2024/08/21/five-perspectives-... [1] https://quantumcomputing.stackexchange.com/questions/30197/#comment52553_30197 https://quantumcomputing.stackexchange.com/questions/30197/#...

r33b33 2y ago

Let's talk about things that actually matter - where to invest in post-quantum world? I'll keep this short. - Google’s Willow quantum chip significantly outpaces current supercomputers, solving tasks in minutes that would otherwise take billions of years. - Hypothesis: Accelerating advancements in tech and AI could lead to quantum supremacy arriving sooner than the 2030s, contrary to expert predictions. - Legacy banking systems, being centralized, could transition faster to post-quantum-safe encryption by freezing transfers, re-checking processes, and migrating to new protocols in a controlled manner. - Decentralized cryptocurrencies face bigger challenges:Hard forks are difficult to coordinate across a decentralized network. - Transitioning to quantum-safe algorithms could lead to longer transaction signatures and significantly higher fees, eroding trust in the system. - If quantum computers compromise current cryptography, tangible assets (e.g., real estate, stock indices) may retain more value compared to digital assets like crypto. Thoughts?

vishnugupta 2y ago
> Legacy banking systems, From what I know about banking world, though second hand, having been working in payment processing systems I can say with confidence that it’s not the compute that’s holding them back.
GTP 2y ago
> Google’s Willow quantum chip significantly outpaces current supercomputers, solving tasks in minutes that would otherwise take billions of years. This is the point that was disputed in the article, and you're instead taking it for granted.
nightowl_games 2y ago
Quantum computing only solves certain classes of tasks faster, not all tasks, not most tasks, only a tiny amount of tasks.
- zeroonetwothree 2y ago
  Actually, Grover’s algorithm would speed up a wide range of tasks. Hardly a tiny amount.

NanoYohaneTSU 2y ago

All of this stuff is so fake. Quantum computing is a vaporware scam and I've been saying it for at least a decade at this point. Waste of time and money by VCs who wants government money forever.

evandrofisico 2y ago
Quantum computing seems to be in the same realm as nuclear fusion as a power source. My Quantum theory professor used to say that in the 1960's, when he was a physics student in the Soviet Union it was "the energy of the future, in 20 years everything will be powered by nuclear fusion". When i was an undergrad student 20 years ago I did hear that "soon, quantum computing will change the world", and yet here we are, every year someone builds a new machine but no one has yet to factorize that 21 = 7x3 in a general way.
- kgwgk 2y ago
  Fusion is the energy of the future – and it always will be.
  - short_sells_poo 2y ago
    You could also say we are already using fusion power - via solar panels. We have a massive ball of plasma powered by fusion in the sky and we are harvesting the energy it creates at an ever growing scale. Whether we'll be able to replicate it profitably at small scale is a question.
    - fluoridation 2y ago
      Of course, by that definition all forms of power generation are fusion, more or less removed from the fusion reactor in question.
      - zeroonetwothree 2y ago
        Some part of geothermal energy comes from gravity which could be argued is not related to fusion (even if the matter undergoing gravity was created in fusion)

RivieraKid 2y ago

What's the most significant useful application of quantum computing, in other words, why should we be excited about QC, how will it improve people's lives?

kuschkufan 2y ago
that one dude that has tried since forever to convince that one city to allow him to dig up that garbage dump for his lost bitcoin wallet password should be able to get the coins without digging then. oh and all other passwords/pass phrases/secrets might get broken too, if they're not yet based on quantum save algos.
n4r9 2y ago
If we extend the definition of "computing" slightly to include "coding and cryptography", then I find superdense coding quite exciting [0]. In a hypothetical quantum internet we could encode and transmit two classical bits in every qubit, which effectively doubles your bandwidth. There's also quantum key distribution [1]. In principle, quantum theory allows Alice and Bob to establish a shared private key which cannot be broken without breaking the laws of physics. You can chat privately with people secure in the knowledge that not even the NSA can possibly be listening. [0] https://en.wikipedia.org/wiki/Superdense_coding https://en.wikipedia.org/wiki/Superdense_coding [1] https://en.wikipedia.org/wiki/Quantum_key_distribution https://en.wikipedia.org/wiki/Quantum_key_distribution
- qup 2y ago
  > You can chat privately with people secure in the knowledge that not even the NSA can possibly be listening. Well, from one possible attack vector, anyway. They can still point lasers at your windows.
- fluoridation 2y ago
  >In a hypothetical quantum internet we could encode and transmit two classical bits in every qubit, which effectively doubles your bandwidth. Hmm... What exactly are you transmitting in such a scenario? What's the physical layer protocol? I.e. what are the wires made of and what flows through them?

gibsonalisha292 2y ago

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Jackosas 2y ago

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