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Test: Quantum Or Not, Controversial Computer No Faster Than Normal
sciencehabit writes The D-Wave computer, marketed as a groundbreaking quantum machine that runs circles around conventional computers, solves problems no faster than an ordinary rival, a new test shows. Some researchers call the test of the controversial device, described in Science, the fairest comparison yet. "...to test D-Wave’s machine, Matthias Troyer, a physicist at the Swiss Federal Institute of Technology, Zurich, and colleagues didn't just race it against an ordinary computer. Instead, they measured how the time needed to solve a problem increases with the problem's size. That's key because the whole idea behind quantum computing is that the time will grow much more slowly for a quantum computer than for an ordinary one. In particular, a full-fledged 'universal' quantum computer should be able to factor huge numbers ever faster than an ordinary computer as the size of the numbers grow." D-Wave argues that the computations used in the study were too easy to show what its novel chips can do.
Is this a case where D-Wave was fraudulently trying to pass something off as quantum when they knew it wasn't, or did they really and truly not know. How could they not know?
This could mean that D-Wave isn't quantum. Or it could mean that quantum computing in general isn't faster than normal computing. I seem to recall some physicist making a bet that quantum computing would be proved equivalent to classical computing.
(T>t && O(n)--) == sqrt(666)
I've been surprised time and again that D-Wave has kept afloat as long as it has. It *will* fail in the end, the only question is how much of that investment money Geordie Rose got safely stashed before the collapse. Their approach is fundamentally not quantum computing.
" didn't just race it against an ordinary computer. Instead, they measured how the time needed to solve a problem increases with the problem's size. That's key "
That is algo design 101. Why has it taken so long for somebody to test it this way?
But the makers of the computer can't find a single problem it solves well. Why is that?
Learn to love Alaska
But won't sniffing it invalidate the test?
Mod me down, my New Earth Global Warmingist friends!
If the computer could open a superposition of the two vials, it would go like shit off a greased shovel.
Wait, I have an idea...they should overclock the quantum chip. By the way, that's twice as funny if you know how it works.
An ordinary $1000 i7 laptop or Xeon server? Or an ordinary $10million mainframe (if you can still spend that much for a mainframe)?
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Originally I meant to bet with Matthias Troyer if the D-Wave machine was truly a quantum annealer. At the time Matthias wrote me:
""Actually, we can't bet anymore since I know the results that we're going to publish and we'll say yes to quantum :-). We should have done the bet a year ago."
So we decided to bet if the current crop of D-Wave machines can already beat conventional computing.
Obviously I lost that bet, but not by much.
It will be interesting to see how the next chip generation will fare, there is still lots of room for higher qubit integration. In comparison to conventional CMOS the D-Wave chip structures are huge.
Conventional chip design doesn't have lots of room at the bottom any more. D-Wave on the other hand still has plenty of room at the bottom.
That's why I will continue to bet on them.
That's been the big question with D-Wave all along. What does it really do, how does it really work, what's it good for, is it real?
Everybody knows what a universal quantum computer is good for - running Shor's algorithm to do factoring and totally wrecking public-key cryptography, plus whatever other problems people care about in the real world. But general-purpose quantum computers so far can't keep enough qbits entangled together to factor numbers bigger than 21 = 3x7, and if anybody's figured out how to do significantly bigger than that, they're keeping it Really Well Hidden (either because they're a government, or because a government will want them to do stuff, or because a government will want them killed.)
Meanwhile, D-Wave has 512 qbits that they claim they'll be able to do something with, and maybe it'll have a chance of being cool or useful. And maybe if you kick in enough megabucks to get a non-disclosure agreement, you'll be able to get some information beyond vague quantumy handwaving. They are the only game in town, after all.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
.... maybe the slahdot stub should have had a link to hear from the horse's mouth?
In this interview Matthias Troyer puts his team's results into the correct context.
They wired the computer into Deepak Chopra's quantum consciousness and all it produced was a stream of pseudoscientific gobbledegook.
But the makers of the computer can't find a single problem it solves well. Why is that?
Aside from profit, why is that question even relevant? It took a century for the geocentric model to give more accurate results than the old heliocentric model. Here we appear to have quite a few independent observers who know quantum annealing when they see it, I am not one of them. Sure it could be a scam but so far I have seen zero evidence supporting that hypothesis.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Looks very much like it, indeed.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
dodging questions.
has an ass to cover with access to the thing.
now, is it any faster than a room temperature traditional analog computer in doing what it does?
world was created 5 seconds before this post as it is.
It took a century for the geocentric model to give more accurate results than the old heliocentric model.
But the "benefits" were immediate. The geocentric model was complicated and incomplete. The heliocentric was "better" day-1 for some things. But the accuracy was more a limit of the measurements at the time. It also took time for others to come on board. People were afraid that if they admitted the heliocentric model was better, they'd be sent to Hell.
Learn to love Alaska
Alot of hype about these quantum computers, D-Wave in particular making claims.
Theres a limited class of problems that that type of computing is applicable to and thses things are not the equivalent of a general purpose computer.
Way too easy? Well let them supply a spectrum of appropriate quantum problems (and not just the subset their hardware's quantum like effect can handle) so that it can be properly demonstrated.
What we need to know about is the existence or non-existence of unfair comparisons, i.e., problems that favor the putatively "quantum" computer.
Since I don't expect a quantum computer to be faster at everything, then finding a bunch of solutions to problems that aren't any faster on the "quantum computer" doesn't prove anything, even if the problems look like the kind of problems you'd hope would be quantum-computery. There's not much more you can do than point to the absence of evidence when the burden of proof isn't on you.
The burden of proof is on the vendor here, and standard of "proof" is conceptually simple at least: demonstrate that for some task this device offers any practical advantage whatsoever over the best available conventional technology. That could be in absolute performance against the best available tech(e.g. ASICs and supercomputers), in relative performance over similarly priced systems, or in some practical measure other than performance, such as power consumption. Any clearly identifiable and verifiable advantage counts as positive proof the vendor has something worth paying attention to.
Of course even comparable performance by a novel architecture on some class of problems is interesting, because of the huge advantages a mature technology enjoys. Performance of a new design even in the same ballpark as a mature design suggests future improvements might be in the works. But it's only a suggestion.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
If you put the quantum computer in a box, how will you know if it's at run level 5 or not?
I think its a pretty nonsensical claim. It is not a quantum computer but only 'a computer that uses quantum effects.' Well transistors use a quantum effect so we could really make the same claim about any computer.
I have done work on the edges of quantum computation, and have to say that I think that real quantum computers are still miles off. The model I am working on is totally fringe - but it emerged from looking at the human brain. Now there is a machine that is a real 'quantum computer' and works at room temperatures. The brains secret is very simple, life does its engineering at an atomic/ molecular scale, and the brains quantum engine is made of individual molecules. The really difficult bit is how it scales it all up to the nerve, axon level and up to the whole brain.
If my model turns out to be correct the basic problem with todays quantum computers is something called 'transience' which is an issue they haven't even started to deal with yet. Replicating the method used by the brain might be a good solution but is not yet anywhere close to being possible - the basic tech needed to build an artificial 'quantum brain' is nanotechnology assemblers. And it seems that no one is seriously even researching them yet so that puts them at 10 to 20 years in the future. (assemblers were estimated at the same 10 to 20 years in the future - 20 years ago)
Below the speed of light Special Relativity is one of the most accurate theories in physics - above the speed of light..