Slashdot Mirror


Molecular Photography

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."

9 of 212 comments (clear)

  1. Molecular computers may benefit from this... by saskboy · · Score: 3, Interesting

    Does anyone know if Synchrotrons, like the one in Saskatoon, SK, Canada play a part in researching molecular computers? The article mentions a magnetic imaging device. Is that like a synchrotron?

    --
    Saskboy's blog is good. 9 out of 10 dentists agree.
  2. Re:That's pretty cool by pVoid · · Score: 5, Interesting
    I don't know how fast Quantum computers are going to make it into the mainstream. I find there is a lack of demand for such powerful computers at this point.

    Sure, biochemists might need the massively paralell processing power to do molecular folding analysis, but regular joe bloes will, IMHO, be very comfortable with quad 2GHz HT Pentium 4s... for a decade at least.

    I feel there will be a rift like there was in the old days when mainframe systems were few and expensive, and the rest were smaller systems.

    Frankly, Quantum doesn't titillate me as much as a nice new nVidida chip at this point.

    The other thing is that massively powerfull paralel processing isn't always a Good Thing. It's just A Thing. Take for example early Pentium Pros which had 16 stage pipelines. Nice in concept, but unless you use it properly, it's not really usefull. Many problems aren't massively parallel... The brain for example, is massively parallel, but not in the sense that many mean: all of your brain isn't adding two million 4 bit integers at the same time. It's doing millions of different tasks...

    Sunday night... must sleep... must shadap.

  3. To the future. by OpenGLFan · · Score: 5, Interesting

    To everyone who has so far commented: so what?
    My mother was born in 1947. The transistor was also invented in 1947, by Shockley. 55 years later, I got her a new computer for Christmas.

    What will I see when I turn 55? I can't wait to find out.

  4. Database indexes by whereiswaldo · · Score: 3, Interesting


    Will quantum computing make using database table indexes obsolete? ie. will the time saved by using an index be small enough that it's not worth the effort to create/maintain one (for most uses)?

    Sounds like "what-if" analysis will be taken to a new extreme, big time.

    1. Re:Database indexes by Uller-RM · · Score: 3, Interesting

      Mathematically, though, as long as you have enough supplemental qubits for error correction, the math works out for any application of Shor's algorithm.

      It's actually pretty ingenious - it takes advantage of entanglement to generate a superposition of all discrete logs of x, and then performs a Fourier transform on it. If the most likely discrete log is odd and non-zero, then you can factor using basic number theory. (If not, rinse and repeat; Shor's algorithm does have a work factor, although its scope isn't as large as with Grover's search algorithm.)

  5. Re:That's pretty cool by pVoid · · Score: 3, Interesting
    Yes, but what will be built?

    I can argue of a future where the emphasis is on the Mobo that can house up to 32 CPUs. and the new AMD Thunderfolts that are so small you can actually fit 32 of them in a mini ATX case... With very low power consumption, and low heat emissions. And big hdd capacity, and loads of RAM, and high bandwidth, and this and that...

    People will have many gimicks to market before they run out of ideas and turn back to the speed issue of a CPU.

    Once again, IMHO.

  6. Re:hmm... by jejones · · Score: 4, Interesting

    Been there, done that; reading core was destructive, so you had to copy back what you just read. Admittedly, it means that there's no read-only version.

  7. Re:Nice, Cool, Wow, but...... by delta407 · · Score: 5, Interesting
    It all depends on your perspective.
    No, it doesn't. There are a lot of technical hurdles to overcome with quantum computing, and this article discusses very few of them.

    For instance, it mentions that they used photons to carry information between ions. That's all well and good, but remember, working with single photons isn't all that easy to begin with, and that pesky Heisenberg guy keps getting in the way. Stray particles remain a problem. (Silicon computing has copper to carry electrons -- what do you to with individual photons?) Furthermore, it does not address the larger problem of decoherence, wherein the state of a quantum computation is lost after a short and unpredictable amount of time.

    Really, what would be better is some great leap in quantum error correction or some quantum computer that does not rely on nuclear magnetic resonance. (NMR can only scale to seven or eight qubits before becoming unusable, at which point quantum computers are rather pointless...)
  8. Did that article teach anyone anything? by blair1q · · Score: 4, Interesting

    Blah blah blah

    The quantum states of phosphorus atoms are particularly long-lived, ...and other neobabble.

    The article tells us basically nothing real, except the names of a few people and that they're working on something called "quantum" computing.

    So here's how it should work (off the top of my head):

    An atom or molecule (a collection of particles) has a set of wave-equation solutions. Each of solutions corresponds to a single point in a lattice, whose coordinates are the quantum numbers; or a single value of an n-tuple whose indices are the quantum numbers; or a single member of a set of n-tuples each of which is identified by a unique combination of quantum numbers...however you want to express it. These quantum numbers are inserted into the wave equation and out pops a solution--a wave-function--that does not diverge or otherwise go kaput.

    If the atom, molecule, collection of particles, etc., is in one state (one combination of quantum numbers; one wavefunction), it's just a matter of applying energy in the right way to push it into another state. The quantum numbers move to a new point in the lattice, you change the n-tuple indices, whatever. You really cause the wavefunction to change, and the spatial arrangement available to the particles moving in the system changes. A spherical shell becomes a dumb-bell shape (not really, but it's a simpler visual than what really happens, so go with it).

    Now you have a binary memory system. Most systems have way more than two states, but only a few will be stable (metastable, actually) enough to be useful for computation. But trinary, quaternary, etc. are certainly not out of the question; though the question is a lot easier if you can still use all this software expertise that has binary math running through its veins.

    Quantum calculations are a lot harder to grok than quantum memory. Something has to work so that the state of the memory actuates another part of the system to undergo a change on a quantum level from one stable state (n-tuple value/wavefunction) to another.

    The Heisenberg Uncertainty Principle would get involved, so the family of states you use would have to be pretty special to keep the particles in knowable states. I think that's what the reporter was really getting at when talking about the phosphorus thing.