Comment by dmfdmf | Hacker News Reader

Comment by dmfdmf | Hacker News Reader

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I get the feeling (and its more likely) that D-Wave has solved the P=NP question in the affirmative and have polynomial equations to solve NP problems. As far as I know, getting qubits to stay coherent is a difficult, unsolved problem as the number of qubits increases. Of the QC research that I have read about they are using a handful of qubits to factor really small numbers like 15. Nobody, at least publicly, is even working with 100's of qubits let alone 2K.

To avoid public disclosure that P=NP (and losing out on any way to monetize their discovery) they are hiding their work behind a "quantum computer" which is a vague and sophisticated enough cover (nobody really understands quantum physics) to dupe some customers while the P equations run in ring-zero of a normal CPU. What would be interesting is to read the sales contracts for these machines. My guess is they are written in such a way that D-Wave makes no promises or guarantee that they are actually using qubits to solve customer's problems, just that they promise to solve customer's NP problems with D-Wave computers, regardless of the method. Moreover, I'd bet that the language states that the machines sold are "equivalent" to a 2000 qubit computer and not necessarily a 2KQbit processors. In this way D-wave is off the legal hook if/when the NP=P solution is revealed by D-Wave or others. My second guess is that these sales contracts are protected by NDA's.

Theres a lot of reasons this isn't possible, let alone probable.

1. The "algorithms" are input by the users, not dwave. Moreover, you don't even have a way to input an NP-complete problem. You can only input the setup for a very specific type of optimization problem.

2. You're not comparing like with like. Even Dwave doesn't claim to have a general, gate based quantum computer like the sub-100 gate quantum computers you're talking about. The also don't claim coherent entanglement of all 2k qubits; they've still failed to convince anybody more than a handful get entangled together coherently during the operation of the device.

3. The dwave has yet to beat a laptop at any problem, let alone the NP-complete problems of their customers. The only people who buy D-Wave systems are those doing pure research.

4. The sales contracts aren't protected by NDAs. I've talked to people who work on Lockheed's D-Wave (at USC), and all their investigations are freely available on the Arxiv.

Okay, so where is the beef? u/krastanov blasted me too but the question remains, what are they doing? How can they sell single computer if your point #3 is true? I would think that researchers must be smart enough to sniff out a scam so I have to think DW must offering some thing new, different or superior to standard CPUs or processing -- even if primitive and expensive. Moreover, if your point #2 is true then how can they claim to be offering a 2K qbit computer? It makes no sense as long as words have real meaning.

Thanks for point #4, I will investigate.

Look at it from the perspective of the people who have bought their computers (e.g. Google, Lockheed). Suppose there's any remote chance this is the first step towards scalable quantum computing. If that's the case, getting your researchers in on the ground floor could lead to what would likely be one of the most valuable pieces of IP since the transistor. D-Wave's patents might not cover it since their patents describe devices that don't really appear to work, and you're big enough to buy them if they do. Governments, every physical science, and plenty of firms big data would be dying to get their hands on your devices.

Now look at the cost of the D-Wave. A few million dollars, compared to the trillions you could make just in licensing fees if it pans out and you were the ones to crack the code. Considering how deep these companies' pockets are, wouldn't you take that bet? I would, and I side with the evaluations of some of the biggest D-Wave skeptics in academia.

Your confusion here is exactly why everyone is so down on D-wave. All the parents points are true which is why it's hard to take their hype seriously.

This post is pretty dense with misconceptions. The two main points that I would like to clarify:

1. In practice classical computers (as in "Intel CPUs") are better at solving the specific problem D-wave is trying to solve (timewise and pricewise).

2. In theory quantum computers can not solve NP problems exponentially faster than classical computers (a strongly believed conjecture).

Fine. I concede your points (except the part about being "dense" with errors).

The essence of my argument still stands and you can easily recast my argument, if you cared to think about it, in a form that is consistent with your vastly superior knowledge of QM, QC, P=NP, etc. If your point #1 is true then how can DW sell a single computer? That makes no sense on the face of it. Do you propose that their customers are buying them in an act of charity or that they are too stupid to notice its a scam? Don't forget these machines sell for millions of Thalers. Clearly, to make a sale DW must have demonstrated some thing superior to the Intel or standard CPU in solving some kind of problem. My guesses at "thing" and "kind" are wrong but my argument stands.

The gist of the issue for me is that DW is claiming to cohere 2000 qbits when the "state of the art" is a handful, at best. So I say, let's see sales contract and check out what are they really selling. That point stands despite your objections too.

A big part of how they sell those machines is indeed PR, and this annoys a lot of quantum information researchers. My guess is that those who buy their machines are just trying to cover all their bases. I do have to concede that their hardware is an interesting exercise in engineering, but nothing more.

Quantum computers do not make NP-hard problems significantly easier to solve than on classical computers.

They're better at prime factorization, but in a way that's well understood (quantum Fourier transform) and possible to simulate on classical computers.

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