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Is this the first practical quantum computer? (D-wave 128 qbit box)

dwavesys.com

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Re: Is this the first practical quantum computer? (D-wave 128 qbit box)

#11

This is a) fake or b) a scam.

DWave just published a paper in Nature that shows that they have built a 8 qubit quantum device. This could be legit. However even if what they say is 100% true and correct, it's still not a 'general' quantum computer, it's only wired for one kind of optimization problem, and it's only 128 qubits which will not allow you to do things current computers can not yet do. You need closer to 1000 qubits for that.

Re: Is this the first practical quantum computer? (D-wave 128 qbit box)

#13
post #8
post #6

Scott Aaronson is an MIT prof and a leading researcher in quantum computing. Here is his take on a recent paper DWave published in Nature: http://www.scottaaronson.com/blog/?p=639 (And the Nature paper: http://www.nature.com/nature/journal/v473/n7346/full/nature1... )

"after four years of the quantum computing community being told to review a restaurant based solely on its ice water and table settings, I’m delighted that D-Wave has finally brought an appetizer." haha... those physicists

Later in that article:

> As some of you might be aware, I’m a theoretical computer scientist, not a physicist (much less an experimentalist).

Re: Is this the first practical quantum computer? (D-wave 128 qbit box)

#16
post #9

D-Wave has been operating under heavy-duty NDA's for a long time. I know of at least two published authors in quantum physics who have signed an NDA and been given the grand tour. I know one well enough to have asked him what he thought without divulging anything he couldn't tell me. He said what D-Wave had when he was there was not a general purpose quantum computer, but rather, a sort of hard-coded specific purpose…

From what I've heard, this thing is designed to solve whatever can be transformed into energy minimization problems - "travelling salesman", routing the wires on printed circuit boards, urban planning, etc etc.

Re: Is this the first practical quantum computer? (D-wave 128 qbit box)

#17
post #10

It's not fake, but it's not the quantum computer you would expect. http://spectrum.ieee.org/computing/hardware/loser-dwave-does... "D-Wave's system uses a chip with little loops of niobium metal containing Josephson junctions—two superconductors separated by an insulator. When the chip is cooled to very low temperatures, tiny electrical currents flowing around the loops exhibit quantum properties, and you can use the…

Oh man, I was a solder monkey for the Orlando group at MIT in my sophomore year, and we also used niobium loops for QBits. That box has got to be pretty big, though. Niobium doesn't superconduct until you bring it down to less that 10K, and to get a stable qbit we had to bring things down into the 100mK range - requiring a helium dilution refrigerator.

http://en.wikipedia.org/wiki/Dilution_refrigerator

Re: Is this the first practical quantum computer? (D-wave 128 qbit box)

#18
post #10

It's not fake, but it's not the quantum computer you would expect. http://spectrum.ieee.org/computing/hardware/loser-dwave-does... "D-Wave's system uses a chip with little loops of niobium metal containing Josephson junctions—two superconductors separated by an insulator. When the chip is cooled to very low temperatures, tiny electrical currents flowing around the loops exhibit quantum properties, and you can use the…

Yes, I wish they'd stop calling it a "quantum computer". It's not a quantum computer. It's a thingy.

That said, I'm quite impressed that D-Wave is finally bringing out a thingy that actually does something. Reading the Scott Aaronson post elsewhere in this thread it appears that they've finally got around to demonstrating that their thingy really does do stuff that involves quantum mechanics.

They're still way behind their implausible schedule, and their thingy still can't do anything that a classical computer can't do a helluva lot faster and cheaper, but I do congratulate them on having a proper working thingy.

But they need to stop calling this thingy a quantum computer.

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