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Some Scientists Question Whether Quantum Computer Really Is Quantum
gbrumfiel writes "Last week, Google and NASA announced a partnership to buy a new quantum computer from Canadian firm D-Wave Systems. But NPR news reports that many scientists are still questioning whether new machine really is quantum. Long-time critic and computer scientist Scott Aaronson has a long post detailing the current state of affairs. At issue is whether the 512 quantum bits at the processor's core are 'entangled' together. Measuring that entanglement directly destroys it, so D-Wave has had a hard time convincing skeptics. As with all things quantum mechanical, the devil is in the details. Still it may not matter: D-Wave's machine appears to be far faster at solving certain kinds of problems (PDF), regardless of how it works."
Does it really matter so long as it does what it says on the tin? It works faster, surely that's all that matters?
So they know where the D-Wave system is, but they cannot definitively measure whether it is actually a quantum computer or not...
A real quantum computer both is and isn't at the same time.
Pretty good is actually pretty bad.
Their computer works not by quantum entanglement but by magic.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
"what's in a name?" Nothing.
The problem is that it's not faster, and while there's a study that concludes it is, the blog post specifically invalidates this:
About the paper claiming it's faster:
Don't think of it as a flame---it's more like an argument that does 3d6 fire damage
It's a quantum adiabatic solver, not a quantum (general purpose) computer. Anyone remember analog computers? Wickedly fast for the problem they were designed to sold, and not worth much doing anything else. D-Wave's machine is in the same category; if you want to solve a particular type of optimisation problem, you can run it on a D-Wave at quite some speed. If you aren;t looking to solve this class of problem, and/or cannot directly and efficiently transform your problem into this, then the D-Wave is useless to you. Additionally, like single-purpose computers past, the D-Wave will be rapidly made obsolete by more generalised computation (and unless D-Wave can keep updating rapidly to keep pace, by classical computation).
Then we not only get a useful machine, we eventually get new science in the bargain. I *like* it!
Please do not read this sig. Thank you.
the less you do, the more you do...
Yeah, sure.
This crazy scientist kidnapped my cat and put it in a box! See if the D-Wave computer can tell me if my cat is alive or not.
I only look human.
My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
The problem here is that the processor is bot simultaniously on and off at the same time, much like a cat in a box. The only way to tell is time, eventually something will start to smell funny.
the machine is really just a quantum annealer. you still need real computers to do your solving for things like computational quantum thermodynamics but where the D-Wave comes in, its really just there to assist the solver cluster with a more terse or efficient algorythm. Not bashing it, seeing as some of their jobs run months or years if the D-Wave manages to carve 20-30% off the time of a solver run, then you just saved ~80 days of work.
as to naysayers who think D-Wave isnt in a true quantum state, heres a research paper on the matter http://arxiv.org/abs/1304.4595
Simulations of quantum versus classical annealers show that a classical one has a fairly uniform probability of solving a problem correctly; a quantum device should instead have a low probability of success at solving hard problems, and a high probability of success solving easy ones. This is what D-Wave is shown to do.
disclosure: i work for a large engineering firm that handles computational fluid thermodynamic and finite element analysis simulation as a service. Id be speechless to have one of these ajacent to my datacenter.
Good people go to bed earlier.
That's what I say, about everything quantum.
Scott's blog post and the comment thread there are really worth reading. Entanglement isn't the only issue. A major part of this also is whether the process that the D-Wave machine is doing is anything that is even faster (either in practice or asymptotically) than a classical computer. Right now, the answer for the first is clearly no. Scott describes mildly optimized systems which have been shown to effectively outperform D-Wave at its own problem. The second question- of asymptotic performance is a little trickier but the answer looks like "probably not". It is also worth noting that the D-Wave machines do a very specific optimization problem, of unclear usefulness, and cannot be used at all for many of things that we think of as what one wants a quantum computer for, like Shor's algorithm http://en.wikipedia.org/wiki/Shor's_algorithm to factor integers.
In fairness to D-Wave though if one thinks of this as essentially a research machine, then not doing as well as conventional systems isn't that much of mark against it any more than very early cars being slower than horses. However, D-Wave is trying to sell these machines commercially. And Scott expresses worry that there's going to be a serious backlash against quantum computing as a whole when the the D-Wave hype bubble bursts. Apparently, D-Wave has now gotten about 100 million in funding, so at least, this is an extremely suboptimal allocation to resources when much more promising academic quantum computer research projects are getting much less money.
Whether this thing turns out to be the real McCoy (dammit Jim, I'm a quantum annealer) or not, one thing D-Wave has done is proven that there are customers who will pay $10M to be on the cutting edge of quantum computing for a few years. This should help boost investment and entrepreneurship in other companies. Eventually, one of them will revolutionize everything.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Um, you realize they claim to have engineered this thing? It wasn't described to them in a dream.
According to the EULA, it is both quantum and non quantum. But if you examine it to determine if it is quantum, then it isn't quantum anymore.
D-Wave is probably a scam, but I work in IT, almost the entire industry is built on scams.
Scott Aaronson comes off as an egotistical man-child that is just angry he's not directly involved in all this.
It's still love - love in this match.
Sig. Sig. Sputnik
Anything can be pushed to the limits of what we know, and on occasion, things work, but not for the reasons you think it did. This is sufficiently close to the cutting edge that it may be operating correctly, but that we only think we understand why.
F'rinstance, for years, we thought about electricity as a liquid. Voltage equaled pressure. Amps equaled volume. The math worked. Nature wiggled it's eyebrows suggestively.
BUT, electricity is NOT a liquid. It works the way it does for completely different reasons. It just took a while for us to figure that out. Yet, even before we understood this, we build practical machinery.
Please do not read this sig. Thank you.
come with a "tiddles inside" logo on them.
Straight from the website:
"Our latest superconducting 512-qubit processor chip is housed inside a cryogenics system within a 10 square meter shielded room."
So in other words, we have a quantum computer, you just can't SEE the quantum computer.
lol, one of the applications of this "quantum computer" is to identify if there is a car in a series of pictures, you just need to hire a couple of Chinese undergrads to sit in that 10 square meter room and hit a yes or no button as they are stream a bunch of images with or without cars.
I haven't thought of anything clever to put here, but then again most of you haven't either.
Now that I've RTFA and through the commentary threads, as a dumb ignorant layperson I get why Scott Aaronsen is right to call out D-Wave. I also get the counter-argument that there needs to be some sort of hype in order to sustain interest in QC. And, the damn thing's got to work eventually. What I'm wondering though is this: Are we (as a society) making an error in trying to use QC to solve problems that are particular to classical computing?
The reason I ask is that a while back on /. I was educated about the nature of Base-10 computing. Prior to this, I'd spent my entire life thinking that Base-10 WAS mathematics, and I'd had no reason to assume or even imagine that there could be any other type of mathematics than Base-10. Base-10 was the pinnacle of mathematics to me. Then I find out that Base-10 is probably the most efficient to date for our society, but that it is not the only way to count; and that Pi is only Pi because of Base-10. Which led me to look at mathematics in a whole new light. Similar with Quantum mechanics--the more I understand about Quantum Mechanics, the more I realize that I have to set aside everything I know about Newtonian physics, because trying to understand quantum physics from a newtonian perspective will always result in failure--while there is a bridge between the two, if I don't take that "bridge" into account then I'm metaphorically trying to judge apples based on my prior experience in dog shows.
Given this, is it fair to hold QC to the same standards as Classical Computing, or should we be looking at entirely new applications of computing? And, is there anyone out there who's staring into the vast unknown and saying "What happens if we do THIS with a QC?"
Here's to hot beer, cold women, and Glaswegian kisses for all.
One of the members of the D-Wave team gave a talk at a physics conference I attended in October. One of the questions was related to why their strategy for quantum computing was so different than other more academic teams. Their answer effectively stated that their system is problem specific with effectively a new hardware setup required for each new problem, while a "true" quantum computer would function like a regular computer.
Damn. All those mod points last week, and now when I for once run in to an under-moded AC post, of course I have non. I would love to read a comparison between the D-Wave computer and analog computers.
Of course it is quantum. The whole universe, including the reactions in the D-Wave are based on the laws of quantum mechanics. Regular computer chips have to take quantum effects into account too, although they try to defeat quantum effects rather than utilize them. Nevertheless, at a basic level the transistors work because of the laws of quantum mechanics.
So how do you want to describe the D-Wave? Do you want to describe it using the laws of Quantum Mechanics? Or do you want to approximate it using a classical model that is carefully chosen to not get the quantum effects wrong?
In either case, as the article says, it's still fast.
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The problem is calling it a "Computer", which it is not really.
A better analogy might be to call it a like on some old school computers, a math co-processor. A math co-processor wasn't a "computer" but rather a processor that offloaded certain tasks that it could handle more efficiently.
I see this as a similar situation. It is really only good at solving very specific problems, outside of which a normal computer would be better served.
They can build these things already? I thought that quantum computers would be only a theoretical idea for many coming years.
if this issue will also affect my FIOS Quantum speeds?
Shut up brain or I'll stab you with a Q-Tip. - Homer Simpson
Integrated circuit chips that use gluons or quarks (or other sub-proton/electron) particle to form arithmetic operations do not exist.
http://arxiv.org/pdf/1305.4904v1.pdf - the "quantum" results can be obtained by a completely classical calculation.
It's pretty obvious who is and who is not reading the article here:
The author concedes that it is possible that this may happen, but:
Additionally the author wants this to succeed because of possible results of its failure:
Seriously, read the whole damn article.
Don't think of it as a flame---it's more like an argument that does 3d6 fire damage
There are 3 possibilities: They built a quantum computer, they are completely faking it, or they invented a whole new branch of physics. Number 1 might get them a Nobel, number 2 is unlikely, and number 3 gets them at least one Nobel with them carried to the podium on the shoulders of the other winners.
From Star Trek, we know that advanced computers will explode if you give them an impossible problem. So give it one of these problems, and if it doesn't explode, it isn't advanced enough. They are also good at killing people in gruesome ways, but testing that will probably get you in trouble.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Seems all they have to do is form a company called Quantum Computer. Then it doesn't matter if the machine really is one, it would simply be a product line under the auspices of "Quantum Computer".
(No doubt there already is a company with that name, so it won't work.)
Tracy Johnson
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BT