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D-Wave: Truth finally starts to emerge

scottaaronson.com

71–80 of 97 posts

Re: D-Wave: Truth finally starts to emerge

#71
post #23

Can anyone attempt to explain this in layman terms? I can't even figure out if this is a real paper or not!

I'm not an expert on quantum computing, but it looks like two points to me: 1) D-Wave devices have finally been proven to meet a fundamental requirement to do quantum computing. This is a significant scientific advancement. 2) Despite this, they don't seem to answer any computational questions more quickly than commodity electronic computers. Again, I'm not an expert. The author's reasoning does seem sound. Still, I'…

> a fundamental requirement to do quantum computing

Yes, and it's a necessary, but not sufficient requirement. They don't have a quantum computer by the usual meanning of that term, but they have a different kind of computer, that may or may not do something better than a normal computer.

Re: D-Wave: Truth finally starts to emerge

#72

OK, so the problem D-Wave has itself defined can be run faster on classical machinery. Does this also hold true for other problems run on the D-Wave?

That question is kind of meaningless.

The D-Wave computer solves a problem. That problem defines the computer. It's a general problem (I don't know if it's turing complete), thus it's a gneral computer.

The problem is that a classical computer can solve the problem faster. In other words that means that a classical computer can emulate the D-Wave faster than the original hardware.

Re: D-Wave: Truth finally starts to emerge

#74

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] http://dwave.wordpress.com/2013/05/08/first-ever-head-to-hea...

[2] http://googleresearch.blogspot.ca/2013/05/launching-quantum-...

Re: D-Wave: Truth finally starts to emerge

#75

Quantum computing reminds me of power from nuclear fusion: it's always 15 years away. I was awfully surprised when I read that D-Wave was already selling quantum computers. I'm glad that someone is willing to counter the hype. I find truth more interesting than fiction.

Coincidentally, D-wave's offices are located in Burnaby, BC, about a 10 minute drive from the offices of General Fusion, another company trying to crack the power-from-nuclear-fusion nut. They too have gotten a lot of flak for their claims about their technology, although I haven't heard much from that end of town lately.

Re: D-Wave: Truth finally starts to emerge

#76
post #21

Earlier quoted context omitted.

I understand some of the words, but the article itself seems to me as ancient Greek. Can someone explain to me what the hell the whole story is about?

A company that claimed to have built a general-purpose quantum computer, which would speed up a lot of computationally-intensive tasks, may have actually built a weaker device that does something called quantum annealing, which allows it to solve only a subset of problems - those that involve finding the lowest value state in a field of lots of values. Furthermore, it doesn't look like the device solves those problem…

Did they actually claim it was a general purpose computer? I have been following them for some time now (albeit not like a hawk) and everything I've seen from them was pretty clear in indicating that they took a different approach, i.e. adiabatic quantum annealing.

Re: D-Wave: Truth finally starts to emerge

#77

I'm glad there are people who understand these things. I hope some day when the field of quantum computing congeals a bit more us mere mortals can begin to understand it as well.

Here's an extremely approachable chapter on quantum algorithms from an undergraduate algorithms course:

http://www.cs.berkeley.edu/~vazirani/algorithms/chap10.pdf

Re: D-Wave: Truth finally starts to emerge

#78

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…

[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's actual power.

Adding emphasis to the main objectives from [2] "to study how quantum computing might advance machine learning." They're still researching things. [1] is a clear attempt to leverage the respectability of Google without actually addressing Aaronson's points.

Re: D-Wave: Truth finally starts to emerge

#79
post #35
post #27

I like that he addresses that his main fear that, if D-Wave does not succeed after riding the marketing hype-machine, a "QC Winter" would likely happen, not unlike the "AI Winter" ( http://en.wikipedia.org/wiki/AI_winter ) that occurred in the late 80's. The AI Winter was caused by a huge amount of over hyped claims and promises by the companies taking part which were never (and could never be) met, leading to the ev…

AI had huge successes though the 80's an early 90's despite the two "AI Winters". However, people generally stop calling something AI once it starts to work. Consider path-finding sometimes it's AI and sometimes not. It's true there was a shifts in research funding (1974–80 and 1987–93) but plenty of things that where under the AI umbrella had moved on to their own separate and a lot of crap that was never going to w…

AI as a whole did not suffer as much as Neural Nets research did.

Re: D-Wave: Truth finally starts to emerge

#80
post #33

Aaronson is fabulous. In my opinion, possibly the best technical author around these days. If you haven't already, his new book[1] is absolutely worth checking out, especially if you're unfamiliar with quantum. --- [1] : http://www.amazon.com/Quantum-Computing-since-Democritus-Aar...

Check out the lecture notes as well, they are thoroughly just as awesome:

http://www.scottaaronson.com/democritus/

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