Slashdot Mirror
Opening Quantum Computing To the Public
director_mr writes "Tom's Hardware is running a story with an interesting description of a 28-qubit quantum computer that was developed by D-Wave Systems. They intend to open up use of their quantum computer to the public. It is particularly good at pattern recognition, it operates at 10 milliKelvin, and it is shielded to limit electromagnetic interference to one nanotesla in three dimensions across the whole chip. Could this be the first successful commercial quantum computer?"
There's only a market for at most 10 of these computers, and only big companies will need one.
I'm going to have to turn in my geek license once and for all...
"operates at 10 milliKelvin"?
"...electromagnetic interference to one nanotesla in three dimensions..."?
Throw in a few universal phase detractors and you've got one heck of a retroencabulator!
Blessed with all the brains that God gave a duck's ass, and twice the charisma.
All I know is that every time I even mention quantum computing my cat gets nervous and absolutely refuses to get in the box.
Glonoinha the MebiByte Slayer
I work with the IQC, we specialize in quantum computing, quantum crypto, and many other things like that. We are also joined partially with the Perimeter Institute (and they do mostly theoretical physics). Anyway, when I first joined the institute, we had a discussion about d-wave. No one believed that it was real, and in fact considers d-wave to be bad for the field. Many of you will probably remember the cold fusion controversy. What happened was that experiment that could not be reproduced was published. This enraged the scientific community. Also, this led to massive funding cuts, and killed off the field. QC has a more stable base, but if d-wave keeps on been publicized like this, and they can never prove their claims (remember that all the experiments and functioning of the QC are considered "trade secrets", they let no one look at it), then we may end up with skepticism from the funders. Keep in mind that the ones who donate have usually no clue what is happening in the field (politicians, ceos, etc, so they are "stupid" enough to be affected by this. Everyone in the field is in the back of their head hoping that its real, but with that chance being so low, we want d-wave to be forgotten.
No, their device is *NOT* a universal quantum computer. So far as I know, no reputable quantum physicist not in their employ has been allowed to examine what they actually do.
Duh, of course you can't examine what a quantum computer is doing. That would change the outcome.
Escher was the first MC and Giger invented the HR department.
"Hello, Quantum Computer Tech Support"
"My new QC is not working, I'd like a replacement under the warranty"
"What makes you think it's broken?"
"It keeps giving wrong results"
"But it's giving the right results in lots of nearby parallel universes. The computer is not broken - you're not observing from the recommended viewing position. This is user error." CLICK.
The opinions expressed here are those of this individual, and may not reflect the policy or practice of the collective
D-Wave has provided neither proof nor convincing evidence that they have, or are capable of building a quantum computer. There are several theoretical limitations that experts remain skeptical have been overcome. Their demonstrations have been suspicious and not open for peer review. In sum, I will believe it when I see it.
See some skepticism here:
http://scottaaronson.com/blog/?p=306
http://scottaaronson.com/blog/?p=291
http://scottaaronson.com/blog/?s=d-wave
I don't want any physicists saying "you forgot the Hademard gate etc."
I think you meant "Hadamard gate".
-- Any Physicist
(Much easier to google for the wikipedia article with that spelling.)
My other car is a 1984 Nark Avenger.
The simplest example of a quantum computing algorithm is Deutsch's algorithm.
Here is how it works. Consider a simple boolean function b_out = f(b_in). It takes an argument that can be 1 or 0 and returns a 1 or 0. There are four possibilities: always zero, always 1, the identify, and logical not.
Now imagine that I give you a black box that computes 'f'. However, it is very, very slow --maybe internally it is computing some NP-complete problem. If you want to know which of the four functions the box calculates, you need to run it twice, once for zero and once for one.
However, suppose you simply want to find out whether zero and one map to the same or different values, i.e., the parity of f. With classical computers, you are screwed. You still have to run the box twice to find that even though you only want to get a single bit of information.
However, you can do better if the black box I gave you is a quantum implementation of f(x). By feeding in a input state that is a superposition of 0 and 1, I can detect in a single evaluation plus some simple operations whether the function is constant or not. However, in doing so I get no information about the specific value. Effectively I can ask any one-bit question about f(x) as efficiently as a specific value.
It unlikely this will every be useful as stated. While it is known how to efficiently translate every classical computing algorithm into a quantum version it is unlikely a real implementation would be within a factor of 2 in speed or cost. I believe it illustrates the basic idea. The character of other quantum algorithms is similar, you often feed in a superposition of all possible inputs and read a single output which is the specific answer you want with high probability without having to ever compute the values you don't want.