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Google Finds D-Wave Machine To Be 10^8 Times Faster Than Simulated Annealing (blogspot.ca)
An anonymous reader sends this report form the Google Research blog on the effectiveness of D-Wave's 2X quantum computer:
We found that for problem instances involving nearly 1000 binary variables, quantum annealing significantly outperforms its classical counterpart, simulated annealing. It is more than 10^8 times faster than simulated annealing running on a single core. We also compared the quantum hardware to another algorithm called Quantum Monte Carlo. This is a method designed to emulate the behavior of quantum systems, but it runs on conventional processors. While the scaling with size between these two methods is comparable, they are again separated by a large factor sometimes as high as 10^8.
A more detailed paper is available at the arXiv.
Note, this is a single SINGLE core doing ONLY quantum annealing simulation and NOT running a CPU optimized algorithm to get the desired answer AND they ignored a "bug" in the D-Wave "quantum annealing machine" because otherwise it wouldn't be "Fair".
As somebody who has used a DWave computer... you're asking the wrong question. They cannot run Firefox at any speed. They're analog computers purpose-built to solve extremely specialized optimization problems. But they don't necessarily "solve" problems -- they're likely to find good near-solutions. If you write an LLVM extension for which bitwise operations are computed as a solutions to an Ising spin glass problem, then it'd be waaay faster to run your Firefox port on DWave hardware backend than it would use a simulated annealing backend.
And that would simply be awful.
You might want to read the article (or even the summary). Google is saying that their results suggest that these computers are NOT just doing simulated annealing, but rather true quantum annealing.
You didn't read the GP's post properly. He said that the critics claimed it never showed any quantum effects. Whether it's a full Turing complete computer is immaterial to that. It's a special purpose computational element which does, despite the critics' claims to actually use quantum effects for a very substantial speed up.
It's not a full quantum computer by any stretch of the imagination. I don't entirely understand it, but from my understanding it's not even especially useful unless your cost function fits a -very- specific form.
Nonetheless, it appears that if you have a real thing for ising models the D-Wave can now find a good minima somewhat faster than classical systems.
So yay. That's pretty cool if true. An actual problem solved with quantum computing based techniques faster than classical solutions. It's a start and an interesting step forwards, since so far they've not been able to beat a simulation of their system running on a PC and now they can. If it's really 10^8 times faster, it would even be faster than a custom classical annealing ASIC built on the same area of silicon.
That makes the result interesting, because it's the first time classical computation has ever been beaten, and that's with vast resources invested in it.
SJW n. One who posts facts.