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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."
Quantum computing is quite simply where we turn after existing silicon is exhausted. Once the basics about the random nature of quantum particles, which is extremely interesting, the meaning of computer and mechanics thereof can be redefined.
Well, yes, that rather is the definition of "hole," isn't it? Having nothing in them is what distinguishes them from the rest of the surroundings.
Scientists ... making tiny holes that contain nothing at all.
So these boffins have developed "nothing", but one day, in the far future, this nothing could be filled with something important.
Wow. What an age we live in.
Unfortunately, I am not Wil Wheaton
They're speed holes, they make the computer go faster....
If you get a quantum 3D-accelerated graphicscard.
I think we can keep recursing like this until someone returns 1
Going back to the same metaphor you began to use, the principle that the Schroedinger's Cat Experiment is suppposed to illustrate is not the concept of superposition (that the cat is both alive and dead whilst in its quantum state in the box) but the concept of decoherence of the quantum state under observation.
It's currently a postulate of quantum mechanics (i.e. everyone observes this phenomenon but nobody can explain it) that observation of a quantum state in a superposition (say, a "qubit" -- perhaps an electron spinning up for 0 and down for 1) will have one of the two values, with certain probability. Once read, the state loses that superposition and remains in the observed state (Recall: in the SCE, the cat stays alive or dead once you open the box).
If you don't want to measure your qubits, and thus maintain their superpositions, entanglements, etc., that's fine ... of course, you can't get any information out of them. If you've properly designed your quantum machine, you may have a guess as to what the possible states are; you may even know the probability of each one.
As soon as you ask to see a qubit, however, it becomes a classical bit and stays one. That's the downside to all this quantum stuff.
Quantum computers also do not mean an end to binary -- currently, since humans have, and are trained to use, primarily classical faculties, quantum research is aimed at extending classical computation. So we typically discuss a "qubit" which may be 0, 1, or some combination thereof (specifically residing in the field C x C). But, if we ever want to interface a quantum computer with a classical instrument (for example, some sort of I/O device, or a classical computer, or a human) then we will unavoidably devolve back to binary.
For more information, I recommend Nielsen & Chuang's book on Quantum Computation and Quantum Information (I think; I don't have it in front of me right now).
Disclaimer: I am not a quantum mechanic. I am, however, an junior finishing up my degrees in mathematics and computer science so that I can go on in a year to work on a PhD in quantum computation. --0x4a6d74
I, for one, can't quite imagine how are they going to stop neutrinos from entering that space...
Simple. They'll just repolarize the quantum invariance field and then bombard it with a tachyon pulse. This creates a standing wave of Heisenberg Flux, which is the only way to be certain the hole is empty.
Operator, give me the number for 911!
A better explaination would be, "Is it a one or a zero?" "Depends on your perspective."
Quantum computing, as I understand it (IANAQCS/P) works off the principal of super position; the ability for a bit to represent multiple bits, simply by the spin of the electron, or some other random thing that I wouldn't know how to explain.
If you defined a zero as a square, and a one as a circle, then a quantum bit would be a cylinder; from one perspective you see the square, yet turn it on its side and you see its other property. But since you have other posibilities (cubes and spheres in this system), the "third dimension" persay has to be explicitly asked for by the requesting computer.
So it's able to perform a massive amount of calculations based on a little bit of data, and store it as one neat little package at the end (either the cube, the sphere, or the cylinder). When someone comes along to ask, "was the answer a zero or a one" then, the only way to answer is "depends on the perspective".
"Victory means exit strategy, and it's important for the President to explain to us what the exit strategy is." G.W.Bush
"How about our Scientists rescue the Hubble Telescope first, something we know works, then worry about the quantum chip later."
No, but first, our scientists have to clean their teeth, then our scientists will be asleep for the next eight hours. Once our scientists have got up in the morning, they'll have a bowl of cheerios and then read the paper for a bit. Then maybe they can tackle the Hubble telescope problem (although the fact that all n million of them are trying to write on the blackboard at the same time does mean they won't make much progress. And the biologists have to sit around twiddling their thumbs because there's not much they can do to help). After Hubble, there's some promising work on cancer they need to finish up, before they can get on with a bit of geology.
Hopefully, someday soon, our scientists will realise that they can get much more done if they allow small groups of themselves to concentrate on different things, so they can make progress in different fields at the same time. In the mean time, though, you're right. They're all wasting their time on this pointless quantum computing nonsense.
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
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.
I like to think of quantum computers as binary on the outside, analog on the inside. You can only read and write in binary, but the operators in the middle can be real valued (complex valued even).
Nielson and Chuang's book is neat (I have it sitting on my floor 3 feet from me ATM). It's mainly written for the physicist to learn quantum circuits and algorithms. It takes a year to read, but by the time you are done, you should be able to read and understand most of the papers in the field.
A much lighter book on the subject is "Explortions in Quantum Computing" by Williams and Clearwater. It gives a basic overview without much assumed knowledge.
Also "Problems & Solutions in Quantum Computing & Quantum Information" by Willi-Hans Steeb and Yorick Hardy has alot of fun problems in it. It's the kind of book thats good to read on a bus, or an airplane.