D-Wave Announces Commercially Available Quantum Computer

New submitter peetm writes "Computing company D-Wave has announced they're selling a quantum computing system commercially, which they're calling the D-Wave One. The D-Wave system comes equipped with a 128-qubit processor designed to perform discrete optimization operations. A qubit is the basic unit of quantum information – analogous to a bit in conventional computing. For a broader understanding of how qubits work, check out Ars Technica's excellent guide."

Quantum annealing

[fph il quozientatore]

The name "quantum computer" is a bit misleading, since this thing as far as I understood is a classical computer that performs quickly an algorithm called quantum annealing (http://en.wikipedia.org/wiki/Quantum_annealing). If I understand correctly, the "128 qubits" part is snake oil, and it has nothing to do with the explanation of qubits given by Ars Technica in the other link.

This has the same central problem as before

[JoshuaZ]

This has the same central problem as before. D-Wave's computers haven't demonstrated that their commercial bits are entangled. There's no way to really distinguish what they are doing from essentially classical simulated annealing. And the set of problems which their machines can supposedly works on is an NP-hard problem minimization problem involving Ising spin where it isn't even clear that from a complexity standpoint that the the problem can be more quickly solved in general by a quantum system. (Essentially we don't know the relationship between BQP, the set of problems reliably solvable on a quantum computer in polynomial time http://en.wikipedia.org/wiki/BQP [wikipedia.org] and NP http://en.wikipedia.org/wiki/NP_(complexity) [wikipedia.org]. Recommended reading that is skeptical of D-Wave's claims is much of what Scott Aaronson has wrote about them. See for example http://www.scottaaronson.com/blog/?p=639 [scottaaronson.com], http://www.scottaaronson.com/blog/?p=198 [scottaaronson.com] although interestingly after he visited D-Wave's labs in person his views changed slightly and became slightly more sympathetic to them http://www.scottaaronson.com/blog/?p=954 [scottaaronson.com].

Re:Quantum annealing

[Coryoth]

As far as I'm aware the 128 "qubits" aren't entangled at all, which means it is useless for any of the quantum algorithms that one generally thinks of (Shor's algorithm for factoring, for example). It simply has 128 separate "qubits" that are queried individually, and is, essentially an augmented classical computer that gains a few minor advantages in some very specific algorithms (i.e. the quantum annealing algorithm) due to this qubit querying, but is otherwise indistinguishable from a really expensive classical computer for any other purpose.

The Author speaks (and cringes a bit)

[TheAlexKnapp]

All - author of the piece speaking here. Yes, I'm aware of the D-Wave controversies, and talked with Scott Aaronson in a later piece at the time of the announcement. I'm cringing a little bit as I re-read this post because I know a heck of a lot more about quantum computing now than I did then. My take on D-Wave's computer now is that it's probably not a 'true' quantum computer in the sense that it involves any quantum speedup or entanglement. That said, I think that their annealing process is interesting in and of itself. I see their quantum computing tag as being akin to calling something '4G' in the wireless world. For those more interested in quantum computing, I updated the post to include some of the Q&A's I did about D-Wave at the time, as well as some of the quantum computing research I've covered since then, including some conversations with quantum computing researchers.

Re:Quantum annealing

[paimin]

"Should of" is not a usage, it's a misspelling of "should've". "Should've" is a usage.