Slashdot Mirror
Quantum Computer To Launch Next Week
judgecorp writes "D-Wave Systems of British Columbia is all set to demonstrate a 16-qubit quantum computer. Simple devices have been built in the lab before, and this is still a prototype, but it is a commercial project that aims to get quantum devices into computer rooms, solving tricky problems such as financial optimization. Most quantum computers have to be isolated from the outside world (look at them and they stop working). This one is an 'adiabatic' quantum computer — which means (in theory, says D-Wave) that it can live with thermal noise and give results without having to be isolated. There's a description of it here — and pretty pictures too."
The problem is, it is a black box. You could hide all the real logic in the interface, you could even be connected to a different box entirely. It is hard to see how this demo proves that anything works.
It reminds me of a 1930s example of a "perpetual motion" IC engine that ran on water. The con-man showed it running in an hotel room in Chicago, connected to the hotel water faucet. The trick, of course, was that he knew enough about the hotel to know that the water faucet was fed via a vertical pipe from the basement pump, and that he could safely pump a certain amount of kerosene into the pipe backwards since it floated on water. The engine was running on the kerosene.
Pining for the fjords
Probably a flaming torch, or something similar, but to be honest how often in modern society are you likey to end up confused. I cannot remember the last time I saw someone wandering around at night with fire on a stick, as opposed to an electric "flashlight"
If you ever drop your keys into a river of molten lava, let'em go, because, man, they're gone.
You want to run to China with a suitcase every time you need to have a secure transaction?
;-)
No. If I needed to give someone in China the new encryption key, I'd simply put my own lock -- which only I have the key to -- on the suitcase. Then I'd ship it to him. Then he'd put his own lock on it (i.e., now it has my and his lock), and ship it back. Then I'd remove my lock and ship it to him. Then he'd remove his lock and open it.
Or something like that
Apology to Ubuntu forum.
Quantum computers even if they can be made practical , will only solve a small subset of problems in computer science that involve highly parallel number calculations or searches. They'll be little or no better than a standard turing machine for sequential (ie most) computing problems where the steps in the program can't be reduced to a simple mathematical formula or sequence or where branching levels are high.
So while various talking heads may waffle on about a new era in computing what they really mean is a new era in certain areas such as factorisation , whereas most of the computing world will carry on as before. Where not going to see quantum powered AI or whatever else we read about in the more on the fringe science mags anytime soon.
What we can't predict is what fields all those parallel computations could open up. I think that the whole duo to quad to xx amout of cores on a consumer chip is just preparing the IT industry to think in parallel processing and mutlithreaded insturctions so everything that can use it does. Let's be honest. Sequential processing is easy to program compared to parallel processing the same task generally. We don't think like that. I tend to think wait 10 years after 8 core desktops become the main percentage of existing consumer desktops; then we'd see some parallel programming advances. We are just starting down that tech tree. We could always decide to travel other paths though.
A small disclaimer: I work on QC.
I think we should all have an unbiased but intense look at what DWave presents. There is big scepticism in the community about adiabatic quantum computation. Specifically it is not sure that it solves the the problem which it is primarily claimed to adress, namely the decoherence. In some sense the Article DWave published on the preprint archive recently about the coupling is interesting. The article about "Thermally assisted adiabatic QC" is also interesting; yet for most of the QC applications it is believed that the computational power comes from entanglement. And entanglent and anything "thermal" in the same energy range seldom are a good combination. Dwave wants to demonstrate on a well choses problem set that their chip works. However there are a lot of thing which they did not discuss.
Some more observations:
1) DWave circumvents the normal scientific way of presenting the thing to the peers first. This is a habit among patent-collecting companies, but it for sure does not contribute in developing a trusting relatenship to the community. On the other hand I could also imagine that DWave is liked so little by a few people that they block papers. However this is nothing we know.
2) Geordie Rose is a little bit to agressive in intentionally devaluating the other approaches. His Blog Entry "Why I hate the Gate Model" is particularly interesting in that aspect. I agree that in his bussiness you sometimes have to kick competitors - sometimes that really helps. However this Entry is IMHO an intentional misunderstanding of what the "Gate model" is about. It is funny that quantum algortihms usually are defined in terms of gates. The task of building a quantum computer is to implement these gates. If you can make an optimization in the end (you can do e.g see Frank Wilhelm et. al), nice for you. Even if you write your Algorithm in terms of gates, nobody is forcing you to do them one by one. However to hate the gate model means to hate your task. But i think Geordies posts main intention was to direct the focus away from implementing an generic QC towards a specific QC. As much as I find his enthousiam about AQC good for the field, one should not redefine the term QC in order to have the most advance QC (Well, that would not be the first time that this happens....).
3) I am missing if they invited anybody from the field to check the experiment. I trust DWave in not faking, but still sombody should have a look at their calculations, ideas and at the final tests. Since they did not publish anythin it would contribute to my interest in this event if they would have some other "referees". Maybe they have.
Nevertheless, i wish DWave good success in the presentation. If the processor does what it is claimed to do, and that reasonable fast (e.g. solving the Ising Model in between 10S and 100S), it a showcase of the things which are yet to come. So even if the term QC should be argued about have this showcase of something non-trivial will help the field. I really hope that political condiderations will be put aside after that and that DWave will be evaluated hard, but unbiased by the community.
Well, if a physics experiment is to destroy the Earth/universe, I would expect this as much more likely than accidentally creating a black hole/strange matter/lower energy state matter that consumes the Earth.
Seriously.
From a computational standpoint, quantum mechanics, behind the scenes, could be running (us in a virtual world) that is completely deterministic. So this would stress that computer possibly beyond the breaking point, "crashing" this world. Or, alternatively, it will fail miserably as that super-reality-computer handles it gracefully, which would also be of extreme interest to us. Or perhaps digital computers, or what passes for them in that world, can operate many times faster than here, and such calculations (like the perfect game of chess) might be trivially quick there.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.