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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

#91

Post by 8080 »

mturmon wrote: post #43
amalcon wrote: post #28

Earlier quoted context omitted.

The way one solves other problems on the D-Wave is by reducing them to the D-Wave problem, so save in extraordinary circumstances the answer will be "Yes."

The "D-Wave problem" (as Aaronson calls it) is kind of peculiar. It's a certain kind of binary optimization problem that comes up in models of magnetic media ("Ising model"). In the original magnetic context, the two states are N and S. Each magnetic element within a 2D array of states jiggles around locally trying to align with its neighbors, and by doing so, each state-flip influences a global energy function. The…

Also note that the topology of dwave's architecture strongly limits the instance of the Ising model you can implement and so the blowup in the instance size is twice: from your problem to the ising model and to map this Ising problem to the dwave's architecture.

Re: D-Wave: Truth finally starts to emerge

#92

Post by nextbigfuture9 »

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'…

How was Aaronson was 100% wrong before -

http://nextbigfuture.com/2013/05/aaronson-intuition-about-wh...

http://www.scottaaronson.com/blog/?p=306

"Even if D-Wave managed to build (say) a coherent 1,024-qubit machine satisfying all of its design specs, it’s not obvious it would outperform a classical computer on any problem of practical interest. This is true both because of the inherent limitations of the adiabatic algorithm, and because of specific concerns about the Ising spin graph problem. On the other hand, it’s also not obvious that such a machine wouldn’t outperform a classical computer on some practical problems. The experiment would be an interesting one! Of course, this uncertainty — combined with the more immediate uncertainties about whether D-Wave can build such a machine at all, and indeed, about whether they can even produce two-qubit entanglement — also means that any talk of “lining up customers” is comically premature."

* Dwave built the machines * Aaronson concedes that Dwave has achieved entanglement with a quantum annealing system for its full 512 qubits. * there were two big sales (Lockheed, Google)

My own prediction from 2006 http://longbets.org/266/

There will be a quantum computer with over 100 qubits of processing capability sold either as a hardware system or whose use is made available as a commercial service by Dec 31, 2010.

128 qubit system was sold in 2010. Quantum entangled annealing is proven in the USC paper of the 128 qubit system that was sold.

Re: D-Wave: Truth finally starts to emerge

#93

Post by nraynaud »

smoyer wrote: post #88
nraynaud wrote: post #83

Earlier quoted context omitted.

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.

Yeah, actually trying to be a smart rocket scientist can be seen as an euristic to make the stochastic process of finding a working rocket design converge faster.

Re: D-Wave: Truth finally starts to emerge

#94

Post by ableal »

Retric wrote: post #35
kruhft wrote: 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…

There's also the fact that some "AI" consisted of redoing - poorly, out of ignorance - what had been done previously in fields such as operations research, optimal control, computer aided design, etc.

Re: D-Wave: Truth finally starts to emerge

#96

Post by blazespin »

Important comment from Geordie on the dwave blog:

"It’s absolutely possible that adding active error correction might help at some point, maybe even in the next generation. If that is the case, we’ll certainly try anything anyone can think of to make the processors work better! In the specific case of exhibiting scaling differences over conventional algorithms, I’d bet we don’t need error correction (at least at the current snapshot) but at the next level (say 2000+ qubits) maybe we might. If we do, no problem — we’ll find a way!"

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

Re: D-Wave: Truth finally starts to emerge

#97

Post by mikecane »

marcosdumay wrote: post #72
mikecane wrote: post #20

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.

>>>That question is kind of meaningless.

Typing it, I knew I ran the risk of the answer being circular, but I still had to ask.

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