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I think the comments show a real desire on the author's part to learn about any possible inaccuracies in his editorial, and I would have wished for a slightly m

I think the comments show a real desire on the author's part to learn about any possible inaccuracies in his editorial, and I would have wished for a slightly more constructive response by Scott. As it is, his main points seem to be: - The Y2K comparison, which, eventually, he seems to agree may indeed be accurate. - The "trying all possible solutions simultaneously" explanation of qc. This is a very common explanation, and from what I gather from Scott's comments is that it's inaccurate for TSP, but possibly right for problems that are better structured to use the technology(?) - An off-topic criticism of the author's previous article calling bitcoin a Ponzi scheme. That article may have been premature in its predictions, but seems accurate on the facts. Who would be miffed of being warned of a ponzi scheme too early? - That matrix multiplication bit, which indeed appears to be mostly gibberish. Although my take-away from the sentence would mostly be the existence of "quantum-resistant" algorithms, which seems accurate (and would also hint at the non-universality of the claims of speedups.) I guess Scott may be unwilling to "do the author's work for them", so to speak. And it's laudable that he mentions some of the good work the WP has been doing, instead of succumbing to the nihilistic cynicism so common these days. But for as long as someone is showing a good-faith effort to improve, I think it's worth for experts in a field to engage constructively with them. Quantum Computing is niche enough that it's entirely plausible that someone with plenty of expertise on computing and the best intentions could end up writing such an article just from a few misunderstandings in their communications with the experts they found.

cycrutchfield 9y ago
Scott's post was not meant to be an honest critique of Vivek's op-ed, as he alluded to by referencing the famous Pete Wells review of Guy Fieri's restaurant. It's intended to be a semi-humorous polemic.
rspeer 9y ago
> The "trying all possible solutions simultaneously" explanation of qc. This is a very common explanation, and from what I gather from Scott's comments is that it's inaccurate for TSP, but possibly right for problems that are better structured to use the technology(?) From what I gather from Scott's comments (and the tagline of his entire blog), this common explanation is basically always incorrect. Quantum algorithms do not try all solutions simultaneously. That's a description of the theoretical model of nondeterministic computing (like where "NP" comes from), not of quantum computing.
- kgwgk 9y ago
  Always, except when you are confronted with a “problem having a structure that lets you set up a pattern of constructive and destructive interference, so that different contributions to each wrong answer cancel each other out while the different contributions to the right answer(s) reinforce.” In particular “factoring and other problems important for public-key cryptography,” which is the subject of the article.
- OscarCunningham 9y ago
  In fact both quantum computers and nondeterministic computers can perform a computation on all possible inputs simultaneously. The difference is in what happens afterwards. A nondeterministic computer halts in the "success" state if any of the individual threads halted succesfully. This turns out to be tremendously useful. A quantum computer run on a quantum superposition of all possible inputs gives you a superposition of the outputs. If you we're to measure it directly you would just get one of the outputs chosen at random. This not useful. But sometimes (on particular problems with a suitable structure) further work can be done on the superposed state before measuring it, in such a way that the results of the measurement are useful.
  - kgwgk 9y ago
    > If you we're to measure it directly you would just get one of the outputs chosen at random. The point is that not all the outputs are equally probable and (in the interesing cases) you will get the “right” answer with high probability.
    - OscarCunningham 9y ago
      My point is that if you do it the naive way then they are all equally likely. You need to do something extra to make the ones you want more likely. And this only works in some cases. (I guess Grover's algorithm works in all cases, but it's not a exponential speedup.)
      - kgwgk 9y ago
DerekL 9y ago
> An off-topic criticism of the author's previous article calling bitcoin a Ponzi scheme. That article may have been premature in its predictions, but seems accurate on the facts. Who would be miffed of being warned of a ponzi scheme too early? Obviously, someone who's already bought in but hasn't cashed out yet.

cycrutchfield 9y ago

Scott's post was not meant to be an honest critique of Vivek's op-ed, as he alluded to by referencing the famous Pete Wells review of Guy Fieri's restaurant. It's intended to be a semi-humorous polemic.

rspeer 9y ago

> The "trying all possible solutions simultaneously" explanation of qc. This is a very common explanation, and from what I gather from Scott's comments is that it's inaccurate for TSP, but possibly right for problems that are better structured to use the technology(?) From what I gather from Scott's comments (and the tagline of his entire blog), this common explanation is basically always incorrect. Quantum algorithms do not try all solutions simultaneously. That's a description of the theoretical model of nondeterministic computing (like where "NP" comes from), not of quantum computing.

kgwgk 9y ago
Always, except when you are confronted with a “problem having a structure that lets you set up a pattern of constructive and destructive interference, so that different contributions to each wrong answer cancel each other out while the different contributions to the right answer(s) reinforce.” In particular “factoring and other problems important for public-key cryptography,” which is the subject of the article.
OscarCunningham 9y ago
In fact both quantum computers and nondeterministic computers can perform a computation on all possible inputs simultaneously. The difference is in what happens afterwards. A nondeterministic computer halts in the "success" state if any of the individual threads halted succesfully. This turns out to be tremendously useful. A quantum computer run on a quantum superposition of all possible inputs gives you a superposition of the outputs. If you we're to measure it directly you would just get one of the outputs chosen at random. This not useful. But sometimes (on particular problems with a suitable structure) further work can be done on the superposed state before measuring it, in such a way that the results of the measurement are useful.
- kgwgk 9y ago
  > If you we're to measure it directly you would just get one of the outputs chosen at random. The point is that not all the outputs are equally probable and (in the interesing cases) you will get the “right” answer with high probability.
  - OscarCunningham 9y ago
    My point is that if you do it the naive way then they are all equally likely. You need to do something extra to make the ones you want more likely. And this only works in some cases. (I guess Grover's algorithm works in all cases, but it's not a exponential speedup.)
    - kgwgk 9y ago

DerekL 9y ago

> An off-topic criticism of the author's previous article calling bitcoin a Ponzi scheme. That article may have been premature in its predictions, but seems accurate on the facts. Who would be miffed of being warned of a ponzi scheme too early? Obviously, someone who's already bought in but hasn't cashed out yet.