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Molecular Photography

Posted by michael on from the say-cheese dept.

med dev writes "An article at New Scientist discusses the latest in quantum computing - 1000 bits stored in the electron spins of a single polymer molecule. Add in a recent release of the how-to for the complete quantum computer, qubits that work, and it may not be much longer before Google is running on a server the size of a sugar cube."

6 of 212 comments (clear)

  1. Access Speed. by Trusty+Penfold · · Score: 5, Informative


    nuclear magnetic resonance (NMR) instrument.

    I've done NMR, it takes ages. Preparing the sample takes about 30 minutes. Running the NMR takes between 1 and 20 minutes depending on what you're measuring. Analysing the results depends on how good you are.

    I can't see google using this any time soon.

  2. Popular science by vlad_petric · · Score: 5, Informative
    Most people don't realize that a quantum computer can't function by itself, i.e. it needs a traditional "front-end". This is mostly due to the fact that quantum circuits can't form cycles, and in order to have a Turing-complete system you need at least 3 loops on top of each other.

    Moreover, the peculiarities that make quantum computing interesting (e.g. the ability to factorize in polynomial time) also make it completely inappropriate for mundane tasks. So please stop the "google in a cube" shit.

    --

    The Raven

    1. Re:Popular science by nihilogos · · Score: 4, Informative

      Most people don't realize that a quantum computer can't function by itself, i.e. it needs a traditional "front-end". This is mostly due to the fact that quantum circuits can't form cycles, and in order to have a Turing-complete system you need at least 3 loops on top of each other.

      What the hell are you talking about. Although it will undoubtably more practical to use a classical computer to run one of the current envisions of a quantum one, that doesn't mean the classical one is required. Quantum computers include classical computers as a subset.

      --
      :wq
  3. Re:Redundancy of information stored? by nihilogos · · Score: 4, Informative

    I have to wonder what type of redundancy and error correction will have to be built into quantum computing.

    Lots and lots. In 1995 Peter Shor (the factoring guy) and Robert Calderbank devised that possiblethe first error correcting code for quantum computers. Many others have been designed, including proposals for some that operate as a natural consequence of the system being used. Here is a good survey of the field.

    It has been shown that if the error rate is below a certain threshold (currently estimated to be one error per 103 operations for optimists, and one per 106 per pessimists) then efficient error corrected quantum computation is possible. The pessimistic estimate is well above what is currently possible experimentally in quantum systems but the problem seems to be an engineering one, not a fundamental one. It should eventually be possible with clever implementations of qubits, shielding and cooling to near absolute zero.

    --
    :wq
  4. Re:Molecular computers may benefit from this... by nounderscores · · Score: 5, Informative

    Synchrotrons are used for x ray crystalography. they can produce X-ray photons at a wide range of frequencies and you can carefully select the photons you want using an x-ray monochromator.

    The X-rays will not tell you anything about the nuclei of the molecules you are looking at, as the photons go through the electrons in the crystalised protein they will make an interference pattern, and from that you can calculate the shape of the electron cloud around the molecule.

    Note that this gives you no infomation on the quantum state of the nuclei, which is what this quantum computer needs to know.

    Nuclear Magnetic Resonance molecular analyisis works in a similar way to Magnetic Resonance Imaging, just on a smaller scale.

    for more information click here

  5. You are wrong - Re:Popular science by MobyDisk · · Score: 5, Informative
    ...the peculiarities that make quantum computing interesting...also make it completely inappropriate for mundane tasks. So please stop the "google in a cube" shit.

    You are incorrect. Classical computers can search an indexed database in log(n) time. Grover's algorithm allows quantum searches to be much faster, perhaps even in constant time. Search engines could benefit immensely from quantum computing.

    Lots of information can be found on Lov Grover's quantum search algorithm. Do a search for it on Google. Dr. Dobb's even analyzed the quantum source code for the algorithm. Pretty cool stuff.