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Supercomputing Science

Quantum Computer To Launch Next Week 224

judgecorp writes "D-Wave Systems of British Columbia is all set to demonstrate a 16-qubit quantum computer. Simple devices have been built in the lab before, and this is still a prototype, but it is a commercial project that aims to get quantum devices into computer rooms, solving tricky problems such as financial optimization. Most quantum computers have to be isolated from the outside world (look at them and they stop working). This one is an 'adiabatic' quantum computer — which means (in theory, says D-Wave) that it can live with thermal noise and give results without having to be isolated. There's a description of it here — and pretty pictures too."
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Quantum Computer To Launch Next Week

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  • by Kris_B_04 ( 883011 ) on Thursday February 08, 2007 @10:22AM (#17933604) Homepage Journal
    FTA
    "Twenty years before most scientists expected it" .....
    "It has been predicted that quantum computing will make current computer security obsolete, cracking any current cryptography scheme by providing an unlimited amount of simultaneous processing resources."

    Just in time to crack Vista.

    Sorry.. Couldn't resist...
    k
    • Re: (Score:3, Funny)

      by Anonymous Coward
      Crack Vista? Hell, RUN Vista... I would love to meet the genius who thought it would be cool to establish a cryptographic handshake for EVERY FRAME of video. Oh... and... IMAGINE A BEOWULF CLUSTER OF THESE!
      • Re: (Score:2, Interesting)

        Well, if a physics experiment is to destroy the Earth/universe, I would expect this as much more likely than accidentally creating a black hole/strange matter/lower energy state matter that consumes the Earth.

        Seriously.

        From a computational standpoint, quantum mechanics, behind the scenes, could be running (us in a virtual world) that is completely deterministic. So this would stress that computer possibly beyond the breaking point, "crashing" this world. Or, alternatively, it will fail miserably as that s
    • by LiquidCoooled ( 634315 ) on Thursday February 08, 2007 @10:27AM (#17933672) Homepage Journal
      Actually, this won't crack vista, but apparantly it will confirm the seating plan for a wedding.
    • by msobkow ( 48369 )


      Given that Vista was already cracked, it's clear that all that was ever needed was the proverbial "million monkeys" trying to find holes in the betas. Quantum computing may come up with an answer faster, but massively parallel algorithms crunch through "travelling salesman" problems with equal ease. Especially when you consider the self-tuning "genetic" nature of those who crack systems for fun or profit -- only the best at coming up with attacks ever deliver more than one crack.

  • I made this amazing water car once that went 300mpg with zero emmisions, but it stopped working as soon as anybody got in it. It was the weirdest thing. Now I understand that it was my quantum flux capacitor that was creating all the problems the whole time.

    Adeptus
  • by LiquidCoooled ( 634315 ) on Thursday February 08, 2007 @10:25AM (#17933652) Homepage Journal
    It is not a general quantum computer.
    It is a single instance specific formula calculator.

    Any problem that can be recast as a two-dimensional Ising model in a magnetic field problem (AKA quadratic integer programming) can in principle be solved using the approach we'll be demo'ing.

    Thats from their blog [wordpress.com]

    There were some interesting questions asked and lots of people are sceptical.
    • by MindStalker ( 22827 ) <mindstalker@@@gmail...com> on Thursday February 08, 2007 @10:36AM (#17933788) Journal
      Umm. No duh. Its been speculated for a long time that general purpose quantum computing would be near impossible. Quantum computers will for a long time be co-processors that do special task that regular computers can't do. This one is built for quadratic equations. Which is exactly what Babbage's "computer" was initially built for. Sorry but we are still a long ways away but snake oil this is not..
      • by julesh ( 229690 )
        Umm. No duh. Its been speculated for a long time that general purpose quantum computing would be near impossible.

        I think you missed the parent's point. This machine is not a general quantum computer (note he didn't say "general-purpose" quantum computer) because it isn't capable of fully entangling all 16 qubits, if I understand the explanations on the blog correctly. IANAPP, etc.
      • by mgiuca ( 1040724 )
        Wait, it seems from TFA that this is a general-purpose computer:

        One very cool thing that we're planning to do in Q2/2007 is to provide free access to one of these systems to people who want to either develop or port applications to it...so if you have an idea for an app that needs a fast NP-complete problem solver, start thinking about what you could do with some serious horsepower.

        ?
      • by Garse Janacek ( 554329 ) on Thursday February 08, 2007 @12:29PM (#17935198)

        Quadratic Integer Programming != "quadratic equations" (though strictly speaking it does involve them). It's not about plugging in the quadratic formula or something, it's about optimizing over a set of quadratic inequalities. This is an NP-Complete problem, and I'm almost certain Babbage's computer was not built to solve an NP-Complete problem...

        This could very well be snake oil, not in the sense that they don't have a device that solves what they say it does, but in their claims about the more general implications: (1) On such small inputs as we can assume they'll be using, of course it's trivial for any computer to solve that problem, so they aren't doing anything special. (2) As another poster points out, it's not even clear the extent to which this is really a "quantum computer." (3) Right now it's not even clear that it's theoretically possible for a quantum device to efficiently solve an NP-Complete problem (e.g. a quantum computer could, in theory, break your RSA key, though there are currently intractable engineering obstacles -- but it would be major news, regardless of engineering issues, if it was even theoretically possible to solve QIP efficiently). It seems odd that someone would announce a device that solves the problem (on very small inputs), without also announcing that e.g. this technique could be extended to larger inputs without exponential blowup (which after all is the only obstacle to solving the same problem classically).

        Personally, I suspect that the device is partial snake oil in the sense that they are being misleading about how it really works, and that the algorithm is total snake oil in the sense that they don't really have an efficient algorithm for QIP in a more general quantum computing setting. But I guess we'll see...

        IIATheoretical Computer Scientist

        • by san ( 6716 )
          So how is this connected to the two-dimensional Ising model? Is it about enumerating all possible states on a finite lattice?

          IAAPhysicist
      • Re: (Score:3, Funny)

        by infinite9 ( 319274 )
        Sorry but we are still a long ways away but snake oil this is not..

        I still think they're making this shit up. "There's a computer in the room back there, but don't look directly at it. Else it will quit working." There's a sign in my local Hooters restaurant that says "This sign is in spanish when you're not looking at it." Is that a quantum sign? I think I'll try that next time one of my applications crashes. "Just stop looking at it and it will work!"
    • by eldavojohn ( 898314 ) * <eldavojohn@noSpAM.gmail.com> on Thursday February 08, 2007 @10:51AM (#17933984) Journal

      There were some interesting questions asked and lots of people are sceptical.
      Disclaimer, I'm not a physicist.

      Well, most importantly, a while back I had read up on the research being done at Los Alamos National Laboratory on quantum computers. Granted, this was 4 or 5 years ago, they have an interesting paper [lanl.gov][PDF warning] where, if you'll look at figures 1 & 2, you'll notice that the number of bits you are able to factor is directly related to the decoherence time.

      Now, if you're not familiar with Shor's Algorithm [wikipedia.org], the values in the first figure might not mean much but, in layman's terms, I believe they were experiencing problems with 8 or more qubits. I remember reading that decoherence would destroy the relationship between the qubits before they could prepare them and do a meaningful computation. I had always thought that this would be an upper bound until someone figured out a way around it. If this computer is also using similar means, I'd like to know what special modification they did to overcome these coherence problems.

      You're correct that there are a lot of important questions to be answered but a 16 qubit computer that is a "a single instance specific formula calculator" as you put it still interests me greatly and may be a giant leap forward in our ability to understand future computers that may be true full blown quantum computers. Why downplay this unless you can directly point out a problem with what they're doing and what they claim they can do?
    • by sanermind ( 512885 ) on Thursday February 08, 2007 @11:42AM (#17934602)
      It's not a big deal that it only solves a particular NP-complete problem.. because if you can solve and one NP-complete problem, you can solve ALL of them. From the wikipedia article [wikipedia.org]

      a deterministic, polynomial-time solution to any NP-complete problem would also be a solution to every other problem in NP
      Anyone who took computer science at a decent school and remembers any of it would remember the whole issue of whether P=NP or not. One of great unsolved problems in mathematics, and the fundamental promise of quantum computers vs. classical ones. And the little tidbit that NP-c problems are cross equivalent.. that if you could solve any ONE of them, you could use that method, translating all others into a formalism that could be solved by the original solution. This is a VERY big thing if it's actually working. Still only 16 bits, but jeesh. Still, I'm not sure what the 'adiabatic' nature means. From perusing the article (which was over my head, to be sure) it sounds like they've achieved some sort of partially locked quantum state that's allowed to evolve slowly, not instantaniously. Sort of a quantum anealing, if you will? They are perhaps wiggling the system on a sort of clock while quantum information exchange can happen in parts between certain but not all parts of the system? In which case, it's still pretty neat, but I don't know about scaling.. It may still take quite some (unrealistic) time to solve problems of larger size with more bits
      • Re: (Score:3, Informative)

        by TheRaven64 ( 641858 )
        This is quite misleading. If you can find a way of solving one NP-complete problem in polynomial time on a classical computing device, then you can solve all NP-complete problems in polynomial time on a classical computer. This is because any NP-complete problem can be reduced to any other NP-complete problem. However, the rules change when you are dealing with quantum computers. It may be that the reduction of one NP-complete problem to another is also an NP-complete problem, and one which the quantum
        • by Gospodin ( 547743 ) on Thursday February 08, 2007 @12:11PM (#17934954)

          How could the rules possibly change in this way? Suppose I have an NPC problem I wish to solve (call it P), and a known quantum algorithm that solves a different NPC problem in poly time (call it Q). In poly time I transform P into Q. In poly time I solve Q using the quantum computer. Then in poly time I transform the solution to Q into a solution for P. If I want, I can then check the solution to P in poly time using a conventional computer (this is guaranteed by the definition of NPC). I only need to invoke quantum computing when I'm solving Q - no other step requires nonpoly time.

          • Re: (Score:2, Insightful)

            by oldmacdonald ( 80995 )
            Gospodin is correct: Solving any NP-Complete problem is sufficient, as all the reductions are polynomial and classical. There are other complexity classes that can involve quantum reductions, but NP isn't one of them.

            That said, there are good reasons to think that quantum computers can't solve NP-Complete problems anyway. Factoring, which breaks RSA, is in NP, but is not NP-Complete. So, even if D-Wave has built a true 16 qubit quantum computer (which I doubt) their claims aren't credible.

        • There are way too many misunderstandings in this thread. I've taken a class at Berkeley on QC, and the best known quantum algorithm for solving NP-C problems is Grover's algorithm: http://en.wikipedia.org/wiki/Grover's_algorithm [wikipedia.org] The hitch is, it only provides quadratic speedup rather than polynomial. So, a problem you can solve in O(2^n) time now takes O(2^(n/2)) time. This would be a big deal if you could make a sufficiently big QC, but it's nothing like the polytime algorithm you get for factoring wi
      • by da cog ( 531643 ) on Thursday February 08, 2007 @02:05PM (#17936446)
        The idea behind an "adiabatic" quantum computer is that you can somehow set up a system so that the solution to a problem that you want to solve is encoded in the system's ground state. Thus, in principle all you have to do is cool the system down so that it's at its lowest possible energy level, measure it, and then "decode" the measurements to obtain your solution. The problem with this is that you can't necessarily know when you've gotten the system to be in the ground state; it is possible for it to get "stuck" in a slightly higher-energy state from which it cannot escape, as there might be a forbidden transition between its current level and the ground state.

        This is analgous to a situation in atomic physics: if you've got an electron in an n=2, l=0 state, then it is hard for it to fall all the way down to the n=1 state because in order to change energy it has to emit a photon which changes its angular momentum and thus increases l, but there is no n=1, l=1 state there's only a n=1, l=0 state, and so the transition is forbidden. (Of course, this is an over-simplification that neglects things like the fact that the electron can change it's spin, but you get the idea.)

        So you don't try to go straight to the ground system that you are interested in, because you don't know for sure that you can get there consistently. Instead, you build a system whose ground state you are sure you can get to, and then you slowly change the configuration of that system until it matches the one that you want to solve. Because you are changing it slowly -- i.e., "adiabatically" -- you should never leave the ground state (even though the ground state itself is changing right under you) and thus when you are done you are guaranteed to be in the ground state of your system of interest, from which you can obtain the solution to your NP complete problem.

        There is a catch, though, which is that you have to have the system be *very* cold, and you have to change it *very*, *very* slowly. And here's where the catch can kill you: as the size of your system increases, the gap between the lowest two energy states decreases *exponentially*. This means that you have to make the system exponentially colder, *and* that you have to change it exponentially slower. Thus, adiabatic computers are not expected to be able to solve NP-complete problems in linear time, as there is still a cost in time (and cooling effort) which grows exponentially with the size of your problem. Nonetheless, it's likely that you can get a quadratic speed-up equivalent to Grover's search algorithm by building such a computer.

        This, by-the-way, is why many quantum computing people believe that D-wave is ultimately going to fail -- probably not with this particular computer, but with scaling it up to the point where it's actually useful. But hey, maybe we're wrong and they've figured it all out; we can certainly hope that's the case. :-)
    • by salec ( 791463 )
      OK, make it a FPGA matrix then...
  • There still so many issues with quantumn computing that haven't been resolved yet. Like for instance how do you get the information out without affecting it...
    • Re: (Score:2, Informative)

      Not entirely true. Naturally you can NEVER read the quantum state of the qbits, because observing them only yields one of the states each qbit is (or could be) in, not all of them. However, should the program be written well enough it is possible to gain information form the observed states. This is sufficient to crack RSA in a very short space of time with relatively few qbits (16 would suffice for many applications if the quantum computer were general purpose) AND give an observable result.
    • by Intron ( 870560 )
      Obviously, you write the output of a quantum computer to a quantum tape drive [quantum.com]
  • Quantum mystery (Score:4, Informative)

    by suv4x4 ( 956391 ) on Thursday February 08, 2007 @10:34AM (#17933758)
    Most quantum computers have to be isolated from the outside world (look at them and they stop working)

    This is often misunderstood. Quantum computers don't stop working when you "look at them", the "observer" metaphor is just a fancy way to say that the wave propagation of a particle collapses when it interacts with another particle.

    Basically, imagine they are waves, propagating from the point of last interaction like expanding spheres. When two particles (spheres) touch each other, they collapse back to being single-point particles, and continue propagation anew until the next collision.

    Which means, look at them all you want, just don't crack the casing open and point a torch inside.
    • Which means, look at them all you want, just don't crack the casing open and point a torch inside.

      Torches can't really be pointed, they just throw off light in all directions. Do you mean a flashlight?
      • by Xzzy ( 111297 )
        In some parts of the world, torch and flashlight are synonymous.
      • by julesh ( 229690 )
        Torches can't really be pointed, they just throw off light in all directions. Do you mean a flashlight?

        In Britain, we call what you Americans call a flashlight a torch.
        • In Britain, we call what you Americans call a flashlight a torch.

          So then what do you call the torches that have a big fire on top, when you need to be clear you're not talking about a flashlight?
          • by alta ( 1263 ) on Thursday February 08, 2007 @10:54AM (#17934028) Homepage Journal
            They call that a flaming stick. Obviously they don't have a firm grasp of the language... They way the talk though, you'd think they'd invented it.
          • Re: (Score:3, Interesting)

            by Manic Miner ( 81246 )
            Probably a flaming torch, or something similar, but to be honest how often in modern society are you likey to end up confused. I cannot remember the last time I saw someone wandering around at night with fire on a stick, as opposed to an electric "flashlight"
            • Probably a flaming torch, or something similar, but to be honest how often in modern society are you likey to end up confused.

              When someone talks about a "pointing a torch". ;-)

              I cannot remember the last time I saw someone wandering around at night with fire on a stick, as opposed to an electric "flashlight"

              What about when someone's going to commit soccer, er, football-related arson?
            • by SirCyn ( 694031 )
              I think he meant torch like acetylene torch, or blow torch; not a medieval torch. Either word isn't very descriptive as to what the product actually is.
            • Re: (Score:2, Insightful)

              by Waffle Iron ( 339739 )

              how often in modern society are you likey to end up confused.

              However, avoiding any confusion can be vitally important. The next time you're straining to hold your front door closed against a mob of attacking zombies, and you yell out to your friends "Get Me A Torch, NOW!", you sure don't want them come back with some wimpy little flashlight.

          • Originally the battery-powered torch was an "electric torch", so if you wanted to distinguish between them I suppose you'd have to use the qualifier.

            However, to avoid any trans-Atlantic confusion, I propose we reinstate the archaic term of "faggot" for the wooden kind.
            • Hell no. I can't even call my IDE disks "master" and "slave" anymore without being arrested by the LAPD.
    • by Loco Moped ( 996883 ) on Thursday February 08, 2007 @10:41AM (#17933850)
      Most quantum computers have to be isolated from the outside world (look at them and they stop working)

      So... in what fundamental way is this different from running Windows?
    • I don't know why this was modded up. It bears no relationship to any physics I know. Quantum mechanics doesn't say anything about expanding spheres that collapse on contact. Certainly nobody expects wavefunction collapse when two particles interact. Really, don't just mod something up because it's in scientific language that you don't understand. Just leave it unmoderated for someone else who knows what they're talking about.
    • the "observer" metaphor is just a fancy way to say that the wave propagation of a particle collapses when it interacts with another particle.

      What is the definition of "interacting"? Take, for example the double-slit experiment - you can fire electrons through a double slit and plot their distribution probabilities to show an interference pattern. Put a detector on one of the slits so you can tell which slit the electron went through and the interference disappears. In the case where you have a detector o
  • by rbarreira ( 836272 ) on Thursday February 08, 2007 @10:37AM (#17933806) Homepage

    It has been predicted that quantum computing will make current computer security obsolete, cracking any current cryptography scheme

    Wrong. As far as current knowledge goes, a quantum computer is not a big help for cracking symmetric ciphers such as Triple DES or AES. It is a big help for RSA, since it can factor numbers in O(number size) time.
    • by julesh ( 229690 )
      Wrong. As far as current knowledge goes, a quantum computer is not a big help for cracking symmetric ciphers such as Triple DES or AES.

      No, but it is rather handy against key exchange protocols, which will put all easily-practicable security systems at risk.
    • Check out Grover's algorithm [wikipedia.org] which could be used in countless different ways to speed up cryptography.

      Someone has a very fast factoring algorithm for quantum computers. Existence of said theorem does not imply that there aren't fast algorithms for other ciphers. But this is a /. quantum computing story whuch means people are allowed to post whatever BS they want and it'll get modded up.

  • Most quantum computers have to be isolated from the outside world (look at them and they stop working).
    Sounds like my Windows boxes. I guess MS was further ahead of the curve than I thought.
  • Quantum computers even if they can be made practical , will only solve a small subset of problems in computer science that involve highly parallel number calculations or searches. They'll be little or no better than a standard turing machine for sequential (ie most) computing problems where the steps in the program can't be reduced to a simple mathematical formula or sequence or where branching levels are high.

    So while various talking heads may waffle on about a new era in computing what they really mean is
    • Re: (Score:3, Funny)

      by geekoid ( 135745 )
      That right, there wont be a need for more then 5 or 6 of these things.
      • by Viol8 ( 599362 )
        I know you're being sarcastic , but as well can all guess there will be a huge need for them. Just not for running web browsers or MS Word on or playing Quake XXII.
        • by geekoid ( 135745 )
          I was paraphrasing a certian IBM executive.

          Barically, he took the same stance about computer that you seem to abuot quantum computers. Of course, he was talking abuot financials.

          You may be right, but I have learned to not underestimate what smart people can do with that much power.

    • The real problem is that if you have a pet at home and one of these computers you'll never be sure if your pet is alive or dead [wikipedia.org].
    • Re: (Score:3, Interesting)

      by kabocox ( 199019 )
      Quantum computers even if they can be made practical , will only solve a small subset of problems in computer science that involve highly parallel number calculations or searches. They'll be little or no better than a standard turing machine for sequential (ie most) computing problems where the steps in the program can't be reduced to a simple mathematical formula or sequence or where branching levels are high.

      So while various talking heads may waffle on about a new era in computing what they really mean is
    • Quantum computers even if they can be made practical , will only solve a small subset of problems in computer science

      Quantum computers are not simply massively parallel machines and there's no reason to expect problems that have significant branching to be any more difficult for quantum computers than problems without branching. Your statement about a "simple mathematical formula" is meaningless - there is (1) no simple formula for factoring and (2) all computer programs (classical of quantum) are built f

  • I am thinking that creating a Shift Register, and a Half Adder would be a nice addition. But I think that reserving my judgement till next week might be a good thing.

    I have also noticed that 20 million dollars was used for startup capitol. If this is so, then the cost of computing power will be affordable using this type of computer more quickly than previous types of computers.
  • by $pearhead ( 1021201 ) on Thursday February 08, 2007 @10:42AM (#17933852)

    solving tricky problems such as financial optimization.
    So you're saying this thing could solve my financial problems?
    • by guruevi ( 827432 )
      Yep, as soon as you buy one, you can file for bankruptcy. It will also not work if you look at it, so the lienholder on your loans (to buy this computer) will not be able to sell it since everybody wants to look at what they buy, and then it stops working... so as soon as you're done with your bankruptcy, you can buy it for a few hundred dollars. It's the perfect scam
      • It will also not work if you look at it

        I never understood this... what's so great about me looking at it against (for example) a flea looking at it. Is intelligence a necessary component of 'collapsing the waveforms' (I really annoyed a teacher once by asking what happened if shroedinger used a cat with fleas.. he couldn't answer)?

        What if you got a completely inanimate recording device to 'look' at it. Would that 'collapse' it too?

        Anyway define 'look'. Since everything effects everything else, does the
        • by guruevi ( 827432 )
          I was being funny about it. TFS says that you can't look at it, which is utterly wrong because you can look at it all you want, you can't read the quantum particle's state without changing it.
  • by Scutter ( 18425 ) on Thursday February 08, 2007 @10:42AM (#17933864) Journal
    The expected app to be demo'ed will be Duke Nukem Forever.
    • by twifosp ( 532320 )
      So that's been the problem with the DNF release! As soon as you talk about it, it disapears. If only Daikatana had been programmed with quantum computers. That one didn't disapear fast enough.
  • by zolaar ( 764683 ) on Thursday February 08, 2007 @10:45AM (#17933902)
    It may launch next week, but it's impossible to say where... </farnsworth>
  • A couple of choice bits from the Slashdot post and TFA:

    "Most quantum computers have to be isolated from the outside world (look at them and they stop working)"

    "that can carry out 64,000 calculations simultaneously (in parallel "universes"), thanks to a new technique which rethinks the already-uncanny world of quantum computing. But the academic world is taking a wait-and-see approach"

    I think I'll take a "wait and see" approach as well....anybody else smell bullshit?
    • by wes33 ( 698200 )

      I think I'll take a "wait and see" approach as well....anybody else smell bullshit?


      or as someone once (almost) wrote: their claim is rank, it smells to heaven. On the other hand, what do they have to gain by making such fools of themselves?
    • Re: (Score:3, Funny)

      by prelelat ( 201821 )

      A couple of choice bits from the Slashdot post and TFA:

      "Most quantum computers have to be isolated from the outside world (look at them and they stop working)"

      "that can carry out 64,000 calculations simultaneously (in parallel "universes"), thanks to a new technique which rethinks the already-uncanny world of quantum computing. But the academic world is taking a wait-and-see approach"

      I think I'll take a "wait and see" approach as well....anybody else smell bullshit?

      I guess we'll have to wait and smell.

  • by Flying pig ( 925874 ) on Thursday February 08, 2007 @10:46AM (#17933916)
    The website emphasises that the machine is remote and that it interfaces via a standard API. How are they going to demonstrate that it is the quantum computer doing the calculation and not a standard digital computer? (And, if the demo is for real, I hope they have figured this out.)

    The problem is, it is a black box. You could hide all the real logic in the interface, you could even be connected to a different box entirely. It is hard to see how this demo proves that anything works.

    It reminds me of a 1930s example of a "perpetual motion" IC engine that ran on water. The con-man showed it running in an hotel room in Chicago, connected to the hotel water faucet. The trick, of course, was that he knew enough about the hotel to know that the water faucet was fed via a vertical pipe from the basement pump, and that he could safely pump a certain amount of kerosene into the pipe backwards since it floated on water. The engine was running on the kerosene.

    • The obvious and scary application for this is factoring public keys. If they can factor say 2048 bit keys in less than an hour then I'd say they have something.
  • They actually turned it on last week, and have spent the last few days trying to figure out if it still exists. It seems to both exist and not exist at the same time.
  • by WED Fan ( 911325 ) <akahige@NOspAm.trashmail.net> on Thursday February 08, 2007 @10:56AM (#17934056) Homepage Journal

    The Quantum Computer launched next week, becoming sentient and self-aware 5 minutes before being turned on. A worm-hole opened shortly after activation, preloading the Quantum OS 3 weeks ago that was announced next week and was ready for installation 2 years before the actual delivery date of February 9, 2021. 4 Hot fixes were waiting, in the quantum queu but won't be loaded until July 3, 2002 due to a lack of connectivity that was fixed in 2008.

    Tasks for the quantum computer are:

    • Create a more human acting Al Gore Animatronic OS
    • Provide at least 3 items that will help Hillary Clinton be more likeable (this is expected to take much of the processing time)
    • Locate every lost sock since the invention of the clothes dryer
    • Prove that God does exist and that he doesn't believe that we exist
    • Comb galactic dictionaries for a word that George W. Bush can't mispronounce
    • Prove Decartes was wrong showing that Britney is incapable of thought, yet still exists
    • Try to resolve conflicting formulas and show that Google really isn't evil

    Failure of the first 2 bullets have caused the new Quantum Computer to commit intellectual suicide and it now spends most of its time watching Buffy reruns and constructing 11 dimensional models of the Babylon 5 sets.

  • by dwalsh ( 87765 ) on Thursday February 08, 2007 @11:00AM (#17934122)
    Answer: Yes. Both.
  • Taken from the blog post...

    One very cool thing that we're planning to do in Q2/2007 is to provide free access to one of these systems to people who want to either develop or port applications to it...so if you have an idea for an app that needs a fast NP-complete problem solver, start thinking about what you could do with some serious horsepower.
  • Bill Cosby (Score:3, Funny)

    by cvd6262 ( 180823 ) on Thursday February 08, 2007 @11:39AM (#17934590)
    God: Noah, I want you to build an ark!

    Noah: Riiiiiiiight!

    God: I'm serious. Build it so many qubits by so many qubits.

    Noah: Riiiiiiiight! What's a qubit?

    God: Um, I used to know that. Uh, that's not important....

    --

    PS - Yes, I know the difference between qubit and cubit, and if you've never heard Bill Cosby's "Noah" routine, I am entirely too old.
  • ...and, of course, I want one.
  • Well, let's see. (Score:5, Interesting)

    by drolli ( 522659 ) on Thursday February 08, 2007 @11:49AM (#17934696) Journal
    A small disclaimer: I work on QC.

    I think we should all have an unbiased but intense look at what DWave presents. There is big scepticism in the community about adiabatic quantum computation. Specifically it is not sure that it solves the the problem which it is primarily claimed to adress, namely the decoherence. In some sense the Article DWave published on the preprint archive recently about the coupling is interesting. The article about "Thermally assisted adiabatic QC" is also interesting; yet for most of the QC applications it is believed that the computational power comes from entanglement. And entanglent and anything "thermal" in the same energy range seldom are a good combination. Dwave wants to demonstrate on a well choses problem set that their chip works. However there are a lot of thing which they did not discuss.

    Some more observations:

    1) DWave circumvents the normal scientific way of presenting the thing to the peers first. This is a habit among patent-collecting companies, but it for sure does not contribute in developing a trusting relatenship to the community. On the other hand I could also imagine that DWave is liked so little by a few people that they block papers. However this is nothing we know.

    2) Geordie Rose is a little bit to agressive in intentionally devaluating the other approaches. His Blog Entry "Why I hate the Gate Model" is particularly interesting in that aspect. I agree that in his bussiness you sometimes have to kick competitors - sometimes that really helps. However this Entry is IMHO an intentional misunderstanding of what the "Gate model" is about. It is funny that quantum algortihms usually are defined in terms of gates. The task of building a quantum computer is to implement these gates. If you can make an optimization in the end (you can do e.g see Frank Wilhelm et. al), nice for you. Even if you write your Algorithm in terms of gates, nobody is forcing you to do them one by one. However to hate the gate model means to hate your task. But i think Geordies posts main intention was to direct the focus away from implementing an generic QC towards a specific QC. As much as I find his enthousiam about AQC good for the field, one should not redefine the term QC in order to have the most advance QC (Well, that would not be the first time that this happens....).

    3) I am missing if they invited anybody from the field to check the experiment. I trust DWave in not faking, but still sombody should have a look at their calculations, ideas and at the final tests. Since they did not publish anythin it would contribute to my interest in this event if they would have some other "referees". Maybe they have.

    Nevertheless, i wish DWave good success in the presentation. If the processor does what it is claimed to do, and that reasonable fast (e.g. solving the Ising Model in between 10S and 100S), it a showcase of the things which are yet to come. So even if the term QC should be argued about have this showcase of something non-trivial will help the field. I really hope that political condiderations will be put aside after that and that DWave will be evaluated hard, but unbiased by the community.

  • ObFuturama (Score:4, Funny)

    by sconeu ( 64226 ) on Thursday February 08, 2007 @12:25PM (#17935142) Homepage Journal
    look at them and they stop working

    No Fair! You changed the outcome by observing it!
  • They make it sound like they have built a device that will solve an arbitrary instance of a particular NP-complete problem (the two dimensional Ising model in a magnetic field). Indeed, they argue that they will be able to solve any problem in NP by using a conventional computer to convert that problem to the one they can solve. It would be a major breakthrough to show that any NP-complete problem can be solved in polynomial time on a quantum computer, but I don't think they've done it. (Factoring can be

  • (look at them and they stop working)

    Just like me when someone knocks on my door at a public toilet. I stop "working", too.
  • With the uncertainty principle, maybe its already computing or not computing for a while yet :-)

    (Maybe exaggerating this princple. You cant resolve a measurement finer than a quantum.)
  • by da cog ( 531643 ) on Thursday February 08, 2007 @02:16PM (#17936624)
    For those of you who know some quantum mechanics, here's what's going on:

    The idea behind an "adiabatic" quantum computer is that you can somehow set up a system so that the solution to a problem that you want to solve is encoded in the system's ground state. Thus, in principle all you have to do is cool the system down so that it's at its lowest possible energy level, measure it, and then "decode" the measurements to obtain your solution. The problem with this is that you can't necessarily know when you've gotten the system to be in the ground state; it is possible for it to get "stuck" in a slightly higher-energy state from which it cannot escape, as there might be a forbidden transition between its current level and the ground state.

    This is analgous to a situation in atomic physics: if you've got an electron in an n=2, l=0 state, then it is hard for it to fall all the way down to the n=1 state because in order to change energy it has to emit a photon which changes its angular momentum and thus increases l, but there is no n=1, l=1 state, there's only a n=1, l=0 state, and so the transition is forbidden. (Of course, this is an over-simplification that neglects things like the fact that the electron can change it's spin, but you get the idea.)

    So you don't try to go straight to the ground system that you are interested in, because you don't know for sure that you can get there consistently. Instead, you build a system whose ground state you are sure you can get to, and then you slowly change the configuration of that system until it matches the one that you want to solve. Because you are changing it slowly -- i.e., "adiabatically" -- you should never leave the ground state (even though the ground state itself is changing right under you) and thus when you are done you are guaranteed to be in the ground state of your system of interest, from which you can obtain the solution to your NP-complete problem.

    There is a catch, though, which is that you have to have the system be *very* cold, and you have to change it *very*, *very* slowly. And here's where the catch can kill you: as the size of your system increases, the gap between the lowest two energy states can decrease *exponentially*. This means that you have to make the system exponentially colder, *and* that you have to change it exponentially slower. In general systems do not behave this badly, but it is expected (and possibly has been shown, I don't remember) that systems which can solve NP-complete problems *do* behave this badly. Thus, adiabatic computers are not expected to be able to solve NP-complete problems in linear time, as there is still a cost in time (and cooling effort) which grows exponentially with the size of your problem. Mind you, you aren't *forced* to move so slowly, but if you don't then you have a good chance of effectively kicking the system into an excited state and thus ending up with something that is not a solution to your problem. Nonetheless, it's likely that you can get somehow a quadratic speed-up (equivalent to Grover's search algorithm) over classical computation by building such a computer.

    This, by-the-way, is why many quantum computing people believe that D-wave is ultimately going to fail -- probably not with this particular computer, but with scaling it up to the point where it's actually useful. But hey, maybe we're wrong and they've figured it all out; we can certainly hope that's the case. :-)

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