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D-Wave: Truth finally starts to emerge

scottaaronson.com

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Re: D-Wave: Truth finally starts to emerge

#81

Post by mbq »

archgoon wrote: post #78
ghshephard wrote: post #74

Earlier quoted context omitted.

Geordie's (Dwave's CTO) rebuttal: [1] "The majority of that post is simply factually incorrect. I used to find this stuff vaguely amusing in an irritating kind of way. Now I just find it boring and I wonder why anyone listens to a guy who’s been wrong exactly 100% of the time about everything. Update your priors, people!! If you want to know what’s really going on, listen to the real experts. Like Hartmut. [2]" [1] h…

[1] Contains no explanation about how Aaronson is 100% wrong. It is pure FUD. He won't actually argue points because that would allow Aaronson to rebut his rebuttal. [2] has little information, and no numbers, or comparisons to other techniques. All it says is "Quantum Computing is Cool! And we're working on NP hard problems." It does say that they have a quantum computer from Dwave, but they make no claims as to it'…

Also the funny part is that there are many nice ML algos that do not need harsh optimisations or even do not need optimisation at all (see random ferns for instance). Thus it might be hype for hype.

Re: D-Wave: Truth finally starts to emerge

#82

Post by lmm »

mikeash wrote: post #62
nraynaud wrote: post #15

Earlier quoted context omitted.

I love this idea of having a computing system that might not work as advertised but still produce the right results in a repeatable manner. When the ESA had a computing system that did not work as advertised, they blew up the GNP of an african country and went straight to the textbooks.

That really confuses me. I haven't been following the story, but how can there possibly be questions over whether the thing is doing what they say it is? Are the results that ill-defined?

D-Wave sells you a "black box" that will solve certain problems. They claim (or at least, used to claim) it's using quantum computing to do so. Without knowing about the internals, there's no way to know if that's true.

Re: D-Wave: Truth finally starts to emerge

#83

Post by nraynaud »

mikeash wrote: post #62
nraynaud wrote: post #15

Earlier quoted context omitted.

I love this idea of having a computing system that might not work as advertised but still produce the right results in a repeatable manner. When the ESA had a computing system that did not work as advertised, they blew up the GNP of an african country and went straight to the textbooks.

That really confuses me. I haven't been following the story, but how can there possibly be questions over whether the thing is doing what they say it is? Are the results that ill-defined?

They are playing with statistics and montecarlo stuff. Somehow it would work too in rocket science, you just have to try a lot of designs and after a while a significant portion of them will reach the moon, but they deemed the convergence speed to low, or the cost to high, I don't remember wich.

edit: a more serious answer is in the article, entanglement or not the algorithm naturally converge towards the solution. And they did not even check with convergence speed (I think the quantic version is meant to be faster) but they checked on some statistical criterion that is different in the quantic version and the plain version.

Re: D-Wave: Truth finally starts to emerge

#84

Post by [deleted] »

ghshephard wrote: post #74
bnegreve wrote: post #26

For the ones that don't want to read the whole post, the Truth is that the 3600 speedup claimed in this article: Commercial quantum computer leaves PC in the dust [1](HN discussion: [2]) isn't worth much. Quoting Scott Aaronson's post: As I said above, at the time McGeoch and Wang’s paper was released to the media [...] the “highly tuned implementation” of simulated annealing that they ask for had already been writte…

Geordie's (Dwave's CTO) rebuttal: [1] "The majority of that post is simply factually incorrect. I used to find this stuff vaguely amusing in an irritating kind of way. Now I just find it boring and I wonder why anyone listens to a guy who’s been wrong exactly 100% of the time about everything. Update your priors, people!! If you want to know what’s really going on, listen to the real experts. Like Hartmut. [2]" [1] h…

[deleted]

Re: D-Wave: Truth finally starts to emerge

#85

Post by raverbashing »

ghshephard wrote: post #74
bnegreve wrote: post #26

For the ones that don't want to read the whole post, the Truth is that the 3600 speedup claimed in this article: Commercial quantum computer leaves PC in the dust [1](HN discussion: [2]) isn't worth much. Quoting Scott Aaronson's post: As I said above, at the time McGeoch and Wang’s paper was released to the media [...] the “highly tuned implementation” of simulated annealing that they ask for had already been writte…

Geordie's (Dwave's CTO) rebuttal: [1] "The majority of that post is simply factually incorrect. I used to find this stuff vaguely amusing in an irritating kind of way. Now I just find it boring and I wonder why anyone listens to a guy who’s been wrong exactly 100% of the time about everything. Update your priors, people!! If you want to know what’s really going on, listen to the real experts. Like Hartmut. [2]" [1] h…

The 3600x speedup is correct. You can't compare the 'exact' solution of the D-Wave problem in the d-wave machine with a probabilistic algorithm like Simmulated Annealing. Sure, in practice you're using the approximate algos, with their comparable speedup.

I think the "skeptics" will bash D-Wave until, but probably after their systems are running circles around traditional computing.

Re: D-Wave: Truth finally starts to emerge

#86

Post by NegativeK »

marshray wrote: post #61
marshray wrote: post #60

Earlier quoted context omitted.

There's an old joke a computer salesmen once told me: Q: What's the difference between a computer salesman and a used car salesman? A: The used car salesman knows when he's lying.

Q: What's the difference between a classical computer salesman and a quantum computer salesman?

A: Give me 10,000 answers and we'll select the one that's statistically significant.

Re: D-Wave: Truth finally starts to emerge

#87

Post by SideburnsOfDoom »

marshray wrote: post #61
marshray wrote: post #60

Earlier quoted context omitted.

There's an old joke a computer salesmen once told me: Q: What's the difference between a computer salesman and a used car salesman? A: The used car salesman knows when he's lying.

Q: What's the difference between a classical computer salesman and a quantum computer salesman?

Is the quantum computer salesman in a superimposition of truth-states?

Re: D-Wave: Truth finally starts to emerge

#88

Post by smoyer »

nraynaud wrote: post #83
mikeash wrote: post #62

Earlier quoted context omitted.

That really confuses me. I haven't been following the story, but how can there possibly be questions over whether the thing is doing what they say it is? Are the results that ill-defined?

They are playing with statistics and montecarlo stuff. Somehow it would work too in rocket science, you just have to try a lot of designs and after a while a significant portion of them will reach the moon, but they deemed the convergence speed to low, or the cost to high, I don't remember wich. edit: a more serious answer is in the article, entanglement or not the algorithm naturally converge towards the solution. A…

"you just have to try a lot of designs"

That's exactly what Wernher von Braun did with his early rocket designs. He (intelligently and quickly) iterated, keeping the parts that worked and getting rid of the parts that didn't.

Re: D-Wave: Truth finally starts to emerge

#89

Post by quantumexpert »

raverbashing wrote: post #85
ghshephard wrote: post #74

Earlier quoted context omitted.

Geordie's (Dwave's CTO) rebuttal: [1] "The majority of that post is simply factually incorrect. I used to find this stuff vaguely amusing in an irritating kind of way. Now I just find it boring and I wonder why anyone listens to a guy who’s been wrong exactly 100% of the time about everything. Update your priors, people!! If you want to know what’s really going on, listen to the real experts. Like Hartmut. [2]" [1] h…

The 3600x speedup is correct. You can't compare the 'exact' solution of the D-Wave problem in the d-wave machine with a probabilistic algorithm like Simmulated Annealing. Sure, in practice you're using the approximate algos, with their comparable speedup. I think the "skeptics" will bash D-Wave until, but probably after their systems are running circles around traditional computing.

Actually the D-Wave machine is also probabilistic.

Re: D-Wave: Truth finally starts to emerge

#90

Post by 8080 »

danbruc wrote: post #25
sbierwagen wrote: post #14

Earlier quoted context omitted.

QC is hard because it requires that the qbits be entangled with each other, but not interacting at all with the rest of the universe. This is comparable to trying to eat rice without a fork, or chopsticks, or allowing air to touch the rice. QC is very, very hard. It is entirely possible we won't see useful QC machines for decades, or even centuries. D-Wave has attracted scepticism because in the many press releases t…

Quantum annealing can be used to factor integers [1] (if those guys are correct) but the current D-Wave machines are probably unable to factor any interesting number. Here are some more hints [2] what is possible or not. [1] http://physics.stackexchange.com/questions/11063/can-quantum... [2] http://physics.stackexchange.com/questions/10496/what-can-th...

Quantum annealing can be used to factor integers in the same way simulated annealing or genetic algorithms can: yes, you can reduce factoring to a SAT problem and then give it to a genetic algorithm for SAT but it will probably take a geological era to factor even relatively small numbers. Quantum computers can factor N digit numbers with N^3 operations with Shor's algorithm, but no one has found a way to factor a number in polynomial time (in theory) with a quantum annealing scheme like the one allegedly implemented by the DWave. And I'm pretty confident that is neither possible.
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