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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
Actually, most of holes on Earth are full on air. Even void isn't quite empty. If you have a couple of atoms forming a particle, the space between them isn't quite empty either - they partially overlap, the uncertainity principle says they "partially are" there. The idea is about making small holes with REAL void - no particles, no photons, no "with a little probability, there" electrons, just total null. Not quite easy. I, for one, can't quite imagine how are they going to stop neutrinos from entering that space...
Anagram("United States of America") == "Dine out, taste a Mac, fries"
Quantum computers will use red smoke (the Rubium cloud). Will we call the hobbiests that push the limits of these machines Quark shakers?
When the people fear their government, there is tyranny; when the government fears the people, there is liberty.
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Four thousand.
I was never quite clear on how the holes from Blackburn, Lancs. could possibly fill the Albert Hall. I mean, they're holes - defined as being something not there. How can they fill anything?
Then I discovered marijuana, and understood :-)
Real Daleks don't climb stairs - they level the building.
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
So it will run Duke Nukem Forever then?
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
...and this is why Moore's Law will continue, even though Moore himself says that it won't. Never underestimate the cleverness of the Human.
"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.
Diamonds are not a metal... and Diamonds have the highest thermal conductivity... the last thing you want here for semiconductor devices is a substrate with the highest electrical conductivity... you want a very good insulator, which also gets heat away very quickly... this is where Diamond layers come in... not solid machined diamonds, but diamond deposited or grown into a thin layer...
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
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.
While I'm not sure there is an explanation that makes intuitive sense, it does appear to be the way the universe works at small scales.
Schroedinger's thought experiment was intended to illustrate the weirdness of the issue by tying the state of a macroscopic object (a cat) to a quantum state (the decay/not decay of the particle), mainly. It's not a realistic experiment because you couldn't isolate the macroscopic contents of the box from the outside world sufficiently (and besides, it's cruel).
But, real experiments do demonstrate that quantum stuff consistently behaves in really bizzare and counterintuitive it-is-but-it-isn't ways.
One famous example is the oft-repeated "double slit" experiment (hopefully I won't mangle the summary too much).
You remember light-as-waves? If you take a coherent light source (i.e. a laser) and shine it onto a screen through a mask with two small parallel slits in it, you will see a pattern on the screen resulting from the two interfering wavefronts.
That's simple enough. But light is also particles (photons). You can put a filter between the lazer and the mask that only allows one photon at a time to dribble through. Now you have individual photons going through the mask, and you see individual spots as they hit the screen. Intuitive enough.
But it starts to get weird. If you measure the brightness of those spots, though, they still follow the brightness of the interference pattern. That would suggest that the photon is going through both slits at once and somehow interfering with itself. Hmm, that's not very intuitive.
But, okay. We can test that by using detectors at the slits to note the photons as they go by. Hmm. No, each photon is only going through one slit or the other, not both at once. So why are we getting the interference pattern? Wait, where did the interference pattern go?
Huh. We stop observing which slit the photon is going through, and the interference pattern comes back (i.e. it effectively went through both slots). We start observing again, and it starts "picking" one or the other slot again...
Basically it looks as if, to employ a gross anthoropomorphism, on quantum scales the universe is "lazy", and only commits to a specific choice if it has to (because somebody is watching). No, that's not intuitive, and no, we have no clue how this happens exactly (although we're getting better at describing it and exploiting it for practical purposes like primitive quantum computers), but that's what happens.
Physicists are wrestling with that one. We don't really know. A person directly observing the quality being tested (directly or via instrumentation) seems to be sufficient, but not necessary.
That's one of the downsides of the "Copenhagen Interpretation", which is the most common interpretation of these phenomena -- that an observer observing "forces" the universe to make a "choice" (the grossly anthropomorphic word choice is mine though -- the actual way of putting it is that the act of observation "collapses the wave function").
There are other interpretations, too, that don't require a privileged position of "observer", but they have other very awkward quirks.
Certainly you shouldn't accept it just because someone says so, or because a few experiments suggest it might be true. In this case, though, the experiments have been repeated too many times by too many different people for the weird results to be the result of experimental error though, and also experiments designed to disprove these behaviors have fai
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