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Oxford Physicist Unloads on Quantum Computing, Says It's a Hype Bubble

38 points by isaacfrond 4y ago

mikewarot 4y ago
I've been digging into QC for the past few months, trying to get to the bottom of the stack and learn exactly how things work. I've concluded that Qubits are best viewed as an (X,Y,Z) vector with a length of one. For some reason |0> is (0,0,1) and |1> is (0,0,-1), and most operations involve rotations around an axis that always goes through (0,0,0) Quantum supremacy seems to require that these states have no noise, and especially no coupling between qubits. Quantum Error Correction at first blush appears to be a way out, but only corrects errors by pushing Qubits back to a superposition of |0> and |1>, and throwing away X and Y values. In order for things like Shor's algorithm to work, you have to be able to make many rotations around the line half way between the X and Z axis (a Hadamard gate). Additionally, you have to make very small angle rotations for the Inverse Quantum Fourier Transform, and phase errors stack up. I welcome any and all corrections to this interpretation of things.
andsoitis 4y ago
Discussion: https://news.ycombinator.com/item?id=32722374 https://news.ycombinator.com/item?id=32722374
ak_111 4y ago
Note that he only recently finished his PhD in a tangential area related to Quantum computing, so he is not a giant in a field like say Aronson who I would be interested in knowing what they think on this industry. I do in fact agree with most of the article. However I also think if you measure ratio of scientific/technological impact to funding, I would place Quantum Computing for higher than many other hype bubbles such as crypto, blockchain, web3. In other words the size of funding QC is getting is nowhere close to the other hype bubbles and there are some significant peer-reviewed results that have been generated from it, so for the time being you can still give it the benefit of the doubt. For example, compare how many QC startups YC has funded (I think 0?) compared to blockchain, crypto, AI-assisted medicine and web3. There is no comparison. Picking on QC is far below my list if you want to have a go at hype bubbles.
- jpgvm 4y ago
  Sequoia and a16z are probably a better measure of hype bubbles, pumped billions into crypto nonsense. They have also both funded QC but to a much lesser degree so I would concur with your analysis.
- texaslonghorn5 4y ago
  Aaronson's short response: https://scottaaronson.blog/?p=6670 https://scottaaronson.blog/?p=6670
alpineidyll3 4y ago
I'll get downvoted into oblivion for this, but dozens of my old academic friends from Harvard are in on this grift. My old advisors own some of the largest enterprises in this 'sector', and all all these people (in private) regard quantum computing as a money grab. At best, as a way to fund research. And that's it! The author of this article is 100% right. Markets are fully aware though, go ahead and try to short any publicly traded QC stock. You can't. There's no shares to borrow and no liquidity on puts...TRUST ME I"M TRYING TO :P These enterprises will continue to offer regular old data analysis dressed-up with quantum storytelling as a prestige tool. That is also the business model of many many very large companies (consulting etc). So it's possible these companies might even do fine, but not because they will have a computational advantage-- Not with these platforms.

38 points by isaacfrond 4y ago

I've been digging into QC for the past few months, trying to get to the bottom of the stack and learn exactly how things work. I've concluded that Qubits are best viewed as an (X,Y,Z) vector with a length of one. For some reason |0> is (0,0,1) and |1> is (0,0,-1), and most operations involve rotations around an axis that always goes through (0,0,0) Quantum supremacy seems to require that these states have no noise, and especially no coupling between qubits. Quantum Error Correction at first blush appears to be a way out, but only corrects errors by pushing Qubits back to a superposition of |0> and |1>, and throwing away X and Y values. In order for things like Shor's algorithm to work, you have to be able to make many rotations around the line half way between the X and Z axis (a Hadamard gate). Additionally, you have to make very small angle rotations for the Inverse Quantum Fourier Transform, and phase errors stack up. I welcome any and all corrections to this interpretation of things.

andsoitis 4y ago

Discussion: https://news.ycombinator.com/item?id=32722374 https://news.ycombinator.com/item?id=32722374

ak_111 4y ago

Note that he only recently finished his PhD in a tangential area related to Quantum computing, so he is not a giant in a field like say Aronson who I would be interested in knowing what they think on this industry. I do in fact agree with most of the article. However I also think if you measure ratio of scientific/technological impact to funding, I would place Quantum Computing for higher than many other hype bubbles such as crypto, blockchain, web3. In other words the size of funding QC is getting is nowhere close to the other hype bubbles and there are some significant peer-reviewed results that have been generated from it, so for the time being you can still give it the benefit of the doubt. For example, compare how many QC startups YC has funded (I think 0?) compared to blockchain, crypto, AI-assisted medicine and web3. There is no comparison. Picking on QC is far below my list if you want to have a go at hype bubbles.

jpgvm 4y ago
Sequoia and a16z are probably a better measure of hype bubbles, pumped billions into crypto nonsense. They have also both funded QC but to a much lesser degree so I would concur with your analysis.
texaslonghorn5 4y ago
Aaronson's short response: https://scottaaronson.blog/?p=6670 https://scottaaronson.blog/?p=6670

alpineidyll3 4y ago

I'll get downvoted into oblivion for this, but dozens of my old academic friends from Harvard are in on this grift. My old advisors own some of the largest enterprises in this 'sector', and all all these people (in private) regard quantum computing as a money grab. At best, as a way to fund research. And that's it! The author of this article is 100% right. Markets are fully aware though, go ahead and try to short any publicly traded QC stock. You can't. There's no shares to borrow and no liquidity on puts...TRUST ME I"M TRYING TO :P These enterprises will continue to offer regular old data analysis dressed-up with quantum storytelling as a prestige tool. That is also the business model of many many very large companies (consulting etc). So it's possible these companies might even do fine, but not because they will have a computational advantage-- Not with these platforms.