Scientists Dubious of Quantum Computing Claims

Dollaz wrote with a link to the International Business Times, which questions the authenticity of D-Wave's Quantum computing. We discussed the 'Sudoku playing' computer yesterday, but scientists in the field have expressed a lot of distrust of the company's findings. The machine was not available for inspection during or after the demo, and even if the technology was working as intended there is some doubt that it can be scaled. The article points out that "notwithstanding lofty claims in the company's press release about creating the world's first commercial quantum computer, D-Wave Chief Executive Herb Martin emphasized that the machine is not a true quantum computer and is instead a kind of special-purpose machine that uses some quantum mechanics to solve problems." Good to see people in the field questioning 'breakthroughs'.

Comments

Maybe, but...

[Flimzy]

Maybe it's not a true quantum "computer", but is that bad? The first electronic "problem solving machines" weren't true computers, either. That doesn't mean that this "custom" quantum machine isn't a useful step in the right direction...

Re:How to verify their claims?

[Ambitwistor]

Such a device has never been built, how do these guys prove they have one? As Scott Aaronson said, they could prove it by producing the prime factors of a 463-digit composite number.

Re:How to verify their claims?

[Surt]

I think Aaronson has unfortunately done only half his homework. A 16 qit computer can't solve that problem (not fast anyway).

They didn't do what they said they did

[QEDog]

There are several things to note about the announcement. First, the emphasis was on selling that this computer can solve NP-Complete problems, something that it is, to say the least, not right. An adiabatic quantum computer, such as the one they claim they had, cannot "solve" NP-complete problems. It can at most give a quadratic improvement, at most. They didn't even showed that the did this. Solving a particular instance of an NP-complete problem (such as the 9x9 sudoku) does NOT mean that you can solve an NP-comp problem. Either they lied, or there were intenionally using language that was not very precise to give the wrong impression. So the things that they said they can do cannot be done.

What did they do? Nobody knows. They were very careful to evade the important question: what did they actually accomplish? They never mentioned qubit decoherence times, fidelity, nothing. These are things they can claim without compromising the trade secrets. They gave a lot of emphasis to saying that the computer is part a classical computer, and part a quantum computer, something that nobody really cares about. What is important is to spell out exactly what was the part of the problem the quantum computer solved.

The CTO has a blog, and he sounds very competent in it. I'm guessing that he just had a lot or pressure from the investors to show *something*. It was just a big show to get some Venture Capitals. Pretty graphics and tech demos are cool for getting fans for videogame consoles and getting VC only, not so much as to make scientific claims.