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Hardware Science Technology

1 Molecule Computes Thousands of Times Faster Than a PC 246

alexhiggins732 writes with this tantalizing PopSci snippet: "A demo of a quantum calculation carried out by Japanese researchers has yielded some pretty mind-blowing results: a single molecule can perform a complex calculation thousands of times faster than a conventional computer. A proof-of-principle test run of a discrete Fourier transform — a common calculation using spectral analysis and data compression, among other things — performed with a single iodine molecule transpired very well, putting all the molecules in your PC to shame."
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1 Molecule Computes Thousands of Times Faster Than a PC

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  • Computronium. (Score:4, Insightful)

    by Sir_Lewk ( 967686 ) <sirlewk AT gmail DOT com> on Saturday May 08, 2010 @05:48PM (#32142228)

    I think we are going to see a lot more of this sort of thing as humans get better and better at organizing matter into computing machines. The future is looking very very bright!

  • Add more table salt.

  • Thats cheating (Score:5, Insightful)

    by imsabbel ( 611519 ) on Saturday May 08, 2010 @05:55PM (#32142288)

    In a way. thats just the same as claiming a laser can caluclate a 2D FFT if you look at the frauenhofer diffraction of an aperture.
    Or that single candle can render better than any GPU by the way a room looks like when its illuminated by it.

    You just have to redefine a basic property of your system as "calculation"

    • Re:Thats cheating (Score:5, Interesting)

      by Platinumrat ( 1166135 ) on Saturday May 08, 2010 @06:08PM (#32142400) Journal
      And that was exactly my final year Physics project, in 1984. Take a slide image, shine a laser through it, put that through a lense. The FFT would be formed at the focal point. We then could apply frequency filters (as another slide) and with another lense I could reconstruct the image (less filtered images). So with modern technology, ie LCD screens and cameras, you could dynamically FFT, filter and reconstruct moving images in real time.
    • Analogue computers can be "1000s" of times faster than their digital equivalents, you just sacrifice a certain level of accuracy. The demonstration in the TFA appears to just be using the quantum properties of the molecule to perform an analogue computation.
    • Re: (Score:3, Informative)

      That's like saying that the only thing a transistor can only compute is how it will behave for given applied voltages across its base and collector. Strictly true, but it's a critical building block. Any time you can deterministically create a particular quantum state, allow it to evolve, and read the output you can perform some quantum computations. Similarly, any classical system can perform some classical computations; the question is whether those computations are useful. Frauenhofer diffraction perform

    • I was aware of the using-diffraction-to-compute-Fourier-transforms idea; in fact, I was under the impression that it was somewhat popular before the advent of digital computers. A really good comparison.

      Still, I think that maybe "cheating" is exactly what we should be doing more of. We can use obscenely-sophisticated multigrid PDE solvers to solve Navier Stokes... or we can build a wind tunnel and instrument it with sensors. What I'm wondering is whether there are other physical processes that are good a

    • You just have to redefine a basic property of your system as "calculation"

      Isn't this what we do with conventional computers? All any electronic computer does is open and close logic gates and send and receive signals in such a way that those operations conceptually map to logical and arithmetical operations in the minds of humans. The collection of colored dots you're looking at right now are only "text" because you have been trained to interpret them that way. Whether any event in the universe is a "calculation" ultimately represents a judgment on the part of a human mind about

  • by Vellmont ( 569020 ) on Saturday May 08, 2010 @05:55PM (#32142298) Homepage

    I really hate it when people come up with the simple "Quantum computer 1000 times faster than conventional computer". It's not just overly simplistic, it's wrong.

    Quantum computers can turn some problems that require exponential time to solve into a polynomial time. So instead of taking 2^n time, it might take n^3 time. That's cannot in any realistic way be described as being "X times faster".

    • by RobVB ( 1566105 )

      So instead of taking 2^n time, it might take n^3 time. That's cannot in any realistic way be described as being "X times faster".

      You can compare specific cases of n. For example, with 2^n for a conventional computer and n^3 for the quantum computer, if n = 24, the quantum computer is roughly 1000 times faster (2^24 / 24^3 = 1213).

      I agree that it's overly simplistic, but it's not always wrong. Just a bit too specific, maybe. And also: try explaining the difference between 2^n and n^3 to the general population.


      • I agree that it's overly simplistic, but it's not always wrong.

        If you're smart and knowledgeable enough to know the cases where the comparison is correct, you didn't need the comparison in the first place.

        try explaining the difference between 2^n and n^3 to the general population.

        Don't. Simply say it fundamentally changes the way computers solve problems, and can make some problems that were nearly insolvable ones into ones that can be solved. Telling them it's 1000 times faster makes it sound like they m

      • I think that explanation would be helpful since not all of us are as deep into math as you are.
        • Re: (Score:3, Informative)

          by RobVB ( 1566105 )

          It has to do with the complexity of calculations, and the time a computer needs to find the solution for a problem with n variables/elements. For a certain way of solving a problem, increasing the amount of variables (n) increases the complexity, and thus the calculating time.

          An example: simulating a traffic situation with n cars. Doing the simulation with 11 cars is more complex than with 10 cars, because there's one extra car that's interacting with all the other cars.

          If a problem is of the order of compl

    • by skine ( 1524819 )

      Yes, such statements are gross simplifications.

      However, saying that "a single molecule can perform a complex calculation thousands of times faster than a conventional computer" is in no way false.

      • It's in no way true either. Whereas the computer performs a calculation, the molecule doesn't actually calculate at all, as it doesn't perform arithmetic. So you're comparing apples and oranges.

        Along the same lines, one could say that a wind tunnel can perform a calculation at least 10^23 (eg Avogadro's constant) times faster than a computer, if you're comparing a snapshot photograph with a simulation program which would try to individually compute the trajectories of all the air molecules in the same vol

        • So, you are trying to tell me that with this molecule, there was no deliberate process for transforming one or more inputs into one or more results, with variable change? You obviously have no idea what a calculation actually consists of. The concept of calculation is not bound up with arithmetic. Almost counter-intuitively, it doesn't even necessarily have to mathematical.
          • I'm merely saying that there is no basis for comparing the molecular input/output transformation with an FFT. The latter is defined in terms of sequences of arithmetical operations, whereas the former is not.

            The commonly accepted way to compare two numerical procedures is by expressing them (perhaps implicitly) as sequences of arithmetical operations. That yields a necessary common basis for comparison, which is lacking here.

            The problem with viewing the dynamics of a molecule as a calculation (or perhap

    • by Kjella ( 173770 )

      So in your opinion the question "Is a computer faster than an abacus?" has no answer then? Seriously, get a grip - it's just to tell that it can do some things much faster and that is why you should care. That's the first thing you should get across in any communication, there's tons of things that are technically correct but uninteresting or useless. If you can't get that across within the first 30 seconds, I got better things to do. Or since I'm sitting here I probably don't, but anyway...

      • Re: (Score:3, Insightful)

        by Vellmont ( 569020 )


        So in your opinion the question "Is a computer faster than an abacus?" has no answer then?

        On many levels, yes. Since the problem you're trying to solve is open ended, there's as many answers to it as their are ends to the question.

        it's just to tell that it can do some things much faster and that is why you should care. That's the first thing you should get across in any communication, there's tons of things that are technically correct but uninteresting or useless. If you can't get that across within the f

    • If by

      Quantum computers can turn some problems that require exponential time to solve into a polynomial time.

      you mean transforming nondeterministic polynomial (NP, or deterministic exponential) into polynomial (P) problems, then this is wrong: [wikipedia.org]

      "There is a common misconception that quantum computers can solve NP-complete problems in polynomial time. That is not known to be true, and is generally suspected to be false."

      The word "some" doesn't save you either, if you do it for one NP-complete problem, you'd just gotten yourself a Fields Medal :)

  • by Traf-O-Data-Hater ( 858971 ) on Saturday May 08, 2010 @05:55PM (#32142300)
    ...one molecule ought to be enough for anybody!
  • I'm no quantum theory expert, but does this represent the limit? Or are there some hypotheses about doing calculations with smaller particles?

    • by Yvanhoe ( 564877 )
      femtotech for the win ! No one says we can't use gluons for that. We just don't understand them well enough.
  • by BitZtream ( 692029 ) on Saturday May 08, 2010 @06:20PM (#32142476)

    I've never seen a quantum computing device smaller than the size of a small room, so I'm not really sure how fair it is to compare it to a PC.

    Really the PC doesn't even use full atoms for calculations, it uses electrons and electron holes in the atoms, and its at least 2000 times smaller than any quantum device I've seen.

    You don't really get to say its one molecule when its a device made up of a fuckton of molecules and you are comparing too it a PC which uses subatomic elements to actually do the work.

    You have a fast calculator ... the size of a room ... which I can put 2000 slower and easier to make calculators in and end up faster.

    Sure, eventually, they'll make it smaller and smaller, but your comparison is like saying using an f16 to deliver mail is faster than using a postal truck to deliver milk. Just because you make two statements that share a verb doesn't mean you've made a comparison thats in any way meaningful.

    • "I've never seen a quantum computing device smaller than the size of a small room, so I'm not really sure how fair it is to compare it to a PC."

      Lets dial that back 60 years

      "I've never seen a computing device smaller than the size of a small room, so I'm not really sure how fair it is to compare it to a team of specialists"

      Interesting.
    • Then, by your comparison, I guess we would have to consider the grid that delivers the power to your computer to be part of your computer, and the plant which produces it, along with all of the various things which go into power production, up to and including the planet itself because we extract resources from it to do this. Perhaps it should even include the sun.
    • Thank god nobody ever looked at UNIVAC and said "Well, my typewriter is much smaller than this -- there's no point in trying to make this beast smaller when it's only slightly faster than I am and I can just solve the problems myself, then type the answers." Don't forget that the first computers were the size of a room.
  • by Wowsers ( 1151731 ) on Saturday May 08, 2010 @06:27PM (#32142530) Journal
    A one molecule computer faster than a PC. I find that hard to believe. My Asus Netbook is powered by one "atom", and it's still dog slow.
  • I want one so i can overclock it by adding neutrons.

  • .... say bye bye to encryption...

    • Encryption that relies on hard problems on computers we're accustomed to, sure, but there are also quantum crypto methods that will become cheap and available in the future. There are special things you can do with quantum crypto (that you can use today if you're rich) that you can't do with ordinary crypto too -- like detecting when people listen in. I don't think this represents the end of home crypto, perhaps a long vacation though.
      • also, plain old XOR (with OTP white noise key the size of the cryptogram) remains unbroken.

      • by Tacvek ( 948259 )

        But the only so-called quantum cryptography I have heard of is hardly cryptography. It is a way to generate a shared secret between 2 computers that happen to be directly linked by optical fiber, while detecting any attempt at eavesdropping. It is worthless unless the two computers that want to communicate have a dedicated fiber line that connects them.[1]

        Further while it prevents eavesdropping, it does not prevent full blown man-in-the-middle, where the fiber is severed, and converted into a pair of fiber

    • by selven ( 1556643 )

      And say hello to theoretically unbreakable (not 10^15 years unbreakable, literally unbreakable) quantum entanglement-based one time pads.

    • Nope. If you're saying a quantum computer can solve NP-complete problems, that's generally believed not to be true (in the same sense that it's generally believed than P != NP). Even if that's not what you're saying, you would have to show that a quantum computer could break, say, AES, in polytime. Grover's algorithm can cut the number of bits required to brute-force in half, but to guard against it, just double the number of bits - 256-bit AES should still be hard to break. So private-key encryption (AES a
  • the molecule might have the right answer, but i imagine that it can only give you a proabilistic answer

  • ...You could run Crysis on about half a ton of iodine?

  • The silicon processor in my PC is just one molecule as well and it can do much more than a FFT.
  • I just wish they would finally come up with something that is production-ready.

    There are so many uses for FFT, it’s not even funny. And all normal algorithms always will be imperfect and slow.

    Instant FFT (and inverse FT) would (also) instantly change the world.

  • Think of all the silicon that is going to be put out of work by one atom of iodine.

Do molecular biologists wear designer genes?

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