Probably the biggest point to take away from the article is this:
> For years, I tirelessly repeated that D-Wave hadn’t even provided evidence that its qubits were entangled—and that, while you can have entanglement with no quantum speedup, you can’t possibly have a quantum speedup without at least the capacity to generate entanglement. Now, I’d say, D-Wave finally has cleared the evidence-for-entanglement bar—and, while they’re not the first to do so with superconducting qubits, they’re certainly the first to do so with so many superconducting qubits.
In other words, this is the first actual evidence that D-Wave even has the potential for quantum speedup.
I love this idea of having a computing system that might not work as advertised but still produce the right results in a repeatable manner. When the ESA had a computing system that did not work as advertised, they blew up the GNP of an african country and went straight to the textbooks.
That really confuses me. I haven't been following the story, but how can there possibly be questions over whether the thing is doing what they say it is? Are the results that ill-defined?
D-Wave sells you a "black box" that will solve certain problems. They claim (or at least, used to claim) it's using quantum computing to do so. Without knowing about the internals, there's no way to know if that's true.
They are playing with statistics and montecarlo stuff. Somehow it would work too in rocket science, you just have to try a lot of designs and after a while a significant portion of them will reach the moon, but they deemed the convergence speed to low, or the cost to high, I don't remember wich.
edit: a more serious answer is in the article, entanglement or not the algorithm naturally converge towards the solution. And they did not even check with convergence speed (I think the quantic version is meant to be faster) but they checked on some statistical criterion that is different in the quantic version and the plain version.
That's exactly what Wernher von Braun did with his early rocket designs. He (intelligently and quickly) iterated, keeping the parts that worked and getting rid of the parts that didn't.
Yeah, actually trying to be a smart rocket scientist can be seen as an euristic to make the stochastic process of finding a working rocket design converge faster.
But there is poor to no evidence that adding more qubits scales linearly or exponentially or worse case at all and what we have is a probability of entanglement across a group of qubits
It has the potential for a "quantum speedup" in the way that D-Wave's marketing defines that term. Just keep in mind that it has no resemblance to the usual meaning in a quantum computing context.
The D-Wave is not a quantum computer (as the term is normaly used), and was never meant to be one.
> For years, I tirelessly repeated that D-Wave hadn’t even provided evidence that its qubits were entangled—and that, while you can have entanglement with no quantum speedup, you can’t possibly have a quantum speedup without at least the capacity to generate entanglement. Now, I’d say, D-Wave finally has cleared the evidence-for-entanglement bar—and, while they’re not the first to do so with superconducting qubits, they’re certainly the first to do so with so many superconducting qubits.
In other words, this is the first actual evidence that D-Wave even has the potential for quantum speedup.