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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."
Indeed, talking about quantum computers as an improvment on silicon computers is like talking about jumbo jets as an improvement over cars. Ie not an improvment at all, unless you have something very specific to do (factor a large integer or cross an ocean). And you need the simpler alternative to use the more advanced one (car to get to the airport, regular computer to feed and extract data for quantum computing).
Quantum Leap was an excellent TV show that ran through the late 80's and early 90's. The premise was that "Dr. Sam Becket" (who now plays Captain Archer on Enterprise) invented a time machine that would allow him to reach points throughout his lifetime. The problem is that he never quite got the kinks worked out of his retrieval program, and now finds himself randomly leaping from life to life. The tagline of the show was, "striving to put right what once went wrong and hoping each time that his next leap will be the leap home." (Usually then followed by us seeing him leaping into someone's life. Something utterly confusing then happens to him and he utters the words, "Oh boy".)
And now you know... the rest of the story.
Javascript + Nintendo DSi = DSiCade
In fact, it would be very surprising if it turns out to be NP-complete, as it is in NP intersect co-NP. Also, no efficient quantum algorithms are known for NP-complete problems, and it is generally suspected that quantum computers won't be able to solve them efficiently. For example, see this semi-technical paper.
;)
You had better get that right in your undergrad thesis
Not exactly. Quantum computers can simulate classical computers with no problems. That's one of the tenets of quantum computation.
If by "no problems" you mean "severe and most likely insurmountable quantum coherence issues". Any quantum computer big enough to simulate a modern sized classical computer will contain so many qubits as to have problems with interference from the outside world. IIRC the problem of quantum coherence is roughly exponential in the number of qubits in a system (one of the reason we don't have 1000 qubit computers sitting around). Just having enough qubits to remember my RAM would get pretty ridiculous.
The truth is that quantum computers, in the forseeable future, will likely be an orthogonal type of computing system to classical computers - a coprocessor used for certain problems with small memory requirements but large search spaces. Many of our most important computations lie in this regime, but I doubt quantum computers will outperform classical computers on most ordinary stuff (i.e. word processing, running a webserver, handling large databases) due to its seriality and memory intensive nature. (Insert quote like "640 k ought to be enough for anybody" here)
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.
It implies no such thing. Traveling salesman problem is NP-complete, and while we have no solid proof that a quantum computer cannot solve an NP-complete problem in polynomial time, Shor's algorithm is also in no way any kind of proof, as integer factorization is merely NP, not fully NP-complete as you claimed.
Yes, IAWAUGTOQC (I am writing an undergrad thesis on quantum computation).
Yes, I do have a degree in physics. You may wish to check said thesis in light of errors explained above.