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Tiny Holes Advance Quantum Computing
Nick writes "Worldwide, scientists are racing to develop computers that exploit the quantum mechanical properties of atoms - quantum computers. One strategy for making them involves packaging individual atoms on a chip so that laser beams can read quantum data. Scientists at Ohio State University have taken a step toward the development of quantum computers by making tiny holes that contain nothing at all. The holes - dark spots in an egg carton-shaped surface of laser light - could one day cradle atoms for quantum computing."
Not exactly. Quantum computers can simulate classical computers with no problems. That's one of the tenets of quantum computation. I would love to see a 747 parallel park in Manhattan. Also, the fact that quantum computers can factor large integers efficiently necessarily implies that they can do other NP-complete problems efficiently, such as the traveling salesman problem. If we can ever get more than seven qubits to behave, we'll be amazed by the things quantum computers can do. But, alas, scientists have only implemented Shor's Algorithm for factoring integers on one number. 15. And hot damn, they got the factors right, 3 and 5. Yes, IAWAUGTOQC (I am writing an undergrad thesis on quantum computation).
Like the article said, the issue isn't processor speed, it's algorithm time as a function of input size, i.e. logN. Factoring integers takes an exponential amount of time on classical computers. The best known classical algorithm (called GNFS) is O(exp((logN)^{1/3}(loglogN)^{2/3})), whereas Shor's algorithm can factor N in O((logN)^3) time. But, Shor takes roughly 2^N qubits to factor N. So, if we're talking about factoring a 200 digit RSA number, that's a whole crapload of qubits to control. Many orders of magnitude more than we can control now. In short, you're absolutely right about quantum computers being completely impractical until there are some huge breakthroughs in engineering and physics. This is why I love being a math major. We don't have to worry about silly things like actually building a quantum computer. We just sit around and daydream about how a quantum computer would work, then when we've got it all figured out, we blame the physicists and engineers for not building one.
You can actually guarantee that it will be empty, by creating wave functions that overlap in such a fashion that the probability of a particle being in that space is, in fact, 0, or, by creating wavefunctions which when combined state that the probability of there not being something in that location is infinite. Picture two asymptotic curves joining at a vertical axis, mirrored.
There are a lot of extremely odd quantum effects which aren't physically possible, in any classical or comprehensible universe, however do happen. For instance, it's possible to create a negative temperature. Not negative, as in minus 22 farenheit, but negative, as in below absolute zero!
This happens when you rapidly invert the polarity of a magnetic field in which is contained a bose-einstein condensate - in the time that it takes for the condensate to re-align it's spin, it has a rapid change from a negative temperature to a positive temperature once more. The energy of a negative temperature is, actually, greater than that of an infinite positive temperature!
Anyway, enough quantum rambling. If you don't believe me, look here.