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IBM Q system in development with working 50 qubit processor

www-03.ibm.com

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Re: IBM Q system in development with working 50 qubit processor

#61

Post by joe_the_user »

Xeoncross wrote: post #54
joe_the_user wrote: post #49

Earlier quoted context omitted.

From your link: "A small 16-qubit quantum computer exists and is available for hobbyists to experiment with via the IBM quantum experience project."

From the link in that sentence: "The IBM Quantum Experience (QX) enables anyone to ... ... explore tutorials and simulations around what might be possible with quantum computing."

That sentences doesn't say the small 5 and 16 bit computers don't exist.

Edit: if you read the whole link, the key description is:

"IBM’s quantum processor is made up of superconducting transmon qubits, located in a dilution refrigerator at the IBM Research headquarters at the Thomas J. Watson Research Center.

Users interact with the quantum processor through the quantum circuit model of computation, applying quantum gates on the qubits using a GUI called the quantum composer, writing quantum assembly language code[1] or through a Python API.[2]"

Which is to say you have both a quantum computer and a simulator in IBM schema (which in the cloud 'cause you can't have supercooled chips in your basement), which is as one would expect running "real" quantum computing is going to be more expensive and uncertain now despite the hope it will give vast speed later.

Re: IBM Q system in development with working 50 qubit processor

#62

Post by Cyph0n »

foreigner wrote: post #48
Cyph0n wrote: post #26

Earlier quoted context omitted.

IBM has been awarded more patents per year than any other company for the last 24 years[1]. In 2016 alone, IBM published ~22 patents per day, and ended up being ~2500 patents ahead of Samsung (#2). [1]: http://www-03.ibm.com/press/us/en/pressrelease/51353.wss

I was responsible for a couple of those parents and I can tell you that's all nonsense. IBM employees are encouraged to patent _anything_, regardless of how useless or silly it may be.

Isn't that kind of the best strategy? You -- as a corporation -- want to make investments for the future. Each patent is a possible income stream in the future if the technology behind the patent somehow becomes "big". So it makes sense to patent everything you can, just for the chance of one of them to go "big".

Companies can't just spend money on research expecting no return, at least not for a long time. That's what academia is built to do.

Re: IBM Q system in development with working 50 qubit processor

#63

Post by kevin_thibedeau »

Xeoncross wrote: post #57
vtomole wrote: post #55

Earlier quoted context omitted.

We've had quantum computers since the 90's. We just haven't had "useful" quantum computers yet [0]. An implementation of quantum computers that is currently flourishing is one that is built out of superconducting circuits. This makes it easier to scale the quantum computer because you can leverage existing nanoelectronic fabrication techniques [1]. [0]: https://en.wikipedia.org/wiki/Timeline_of_quantum_computing [1]:…

> "We've had quantum computers since the 90's". It wasn't until 2005 we had the first (probable) qubyte created at the University of Innsbruck in Austria.

You don't need bytes to do computation.

Re: IBM Q system in development with working 50 qubit processor

#64

Post by StephenMelon »

JepZ wrote: post #59

Presenting the pictures of a quantum computer with adbobe flash is an impressive combination of technologies. I hope they are use a different technology stack to develop the OS of that machine ;-)

Well making Flash work on mobile is one potential use for quantum computing I guess? :D

Re: IBM Q system in development with working 50 qubit processor

#65

Post by powertower »

Certhas wrote: post #53
powertower wrote: post #47

I've been following quantum computing since D-Wave made its press release some years back. Now I'm a complete skeptic. The huge red flag I can't get over is if it is as so, why can no one validate it after all this time? Why is there the proverbial "it works but not in the way you think it works" (i.e., quantum annealing) or "it works but we can use non-QM systems to simulate it faster, better, cheaper by a factor of…

Because you have to build the quantum computer in a world that is overwhelmingly classical. There are no qualifiers along the lines of "underlying phenomena". It's simply difficult to get a stable enough interface between the classical and the quantum, so you can control it, while at the same time isolating it enough that it doesn't decohere to classicality. Who knows, maybe reliable scalable quantum computation trul…

But they have already solved the engineering problems (at least 10 years ago).

They already have "qbits".

The interface issues look to be 98% solved.

And the temperature cooling, the EM shielding, and everything else (that is outside the circuitry design and the physical chipset), a person with a budget of 80,000 USD can recreated in his garage.

Its the results I can't understand.

Why can't X qbits, in the time they stay coherent, produce results that agree with the mathematical analysis of the setup? Why is it always off by a factor so large that its not even productive for any task.

My understanding of it is not complete, this is why I ask. Is the interface issue only 2% solved (and not 98%), etc.?

Re: IBM Q system in development with working 50 qubit processor

#66

Post by ihaveahadron »

computer hardware, seems, especially compared to like the eighties to the nineties, stagnant. we won't see much in hardware to care about until a computer hardware revolution ie. quantum processors

this is a "super summary" of obvious shit that is WAY too little understood by, fucking anyone

Re: IBM Q system in development with working 50 qubit processor

#67

Post by sampo »

Zaak wrote: post #29
gnode wrote: post #22

Earlier quoted context omitted.

Do you know what the implications are for symmetric ciphers or [elliptic curve] Diffie-Hellman key exchange? I.e. will forward secrecy still hold up against such future quantum computing?

The implication for symmetric ciphers is that key lengths will need to be doubled. 128-bit ciphers like standard AES have 64-bit security against a quantum attack. I expect to see 256-bit keys adopted widely in the not-too-distant future. I don't know off the top of my head what the implication for key exchange would be, but I know that anything that depends on the discrete logarithm problem for security is vulnerabl…

With a quantum computer and Grover's algorithm, 128-bit AES is breakable in 2^64 steps. But the quantum computer still needs to have a 128-bit quantum memory.

Re: IBM Q system in development with working 50 qubit processor

#68

Post by rbanffy »

Zaak wrote: post #46
rbanffy wrote: post #44

Earlier quoted context omitted.

We can try to partition the machine so your process can use some qubits and mine uses others. I suppose a classical computer would be running the OS, at least at first.

Yeah, if you have a 5000-qubit computer and two people want to run 2000-qubit jobs, I can see them being able to run simultaneously. There will always need to be a classical computer running the quantum computer.

> There will always need to be a classical computer running the quantum computer.

Not sure about the need, but it sure is convenient. Quantum computers are not always better for all kinds of problems and being able to route different jobs to different parts of the system should be an advantage. All this looks a lot like a digitally controlled analog computer or something that can program FPGAs on-the-fly.

Re: IBM Q system in development with working 50 qubit processor

#69

Post by jackfoxy »

greeneggs wrote: post #41
vtomole wrote: post #31

Earlier quoted context omitted.

It's a bit too early for quantum computers to do fault-tolerant (error corrected) computation. This is because you need more than one physical qubit to make a logical (error corrected) qubit. You need 7 physical qubits to encode a logical qubit if you use the Steane code [0]. So with 50 qubits, they could theoretically make 7 error corrected qubits. [0]: https://en.wikipedia.org/wiki/Steane_code

In fact, the smallest quantum error-correcting code using qubits uses only five qubits. [1] So you could fit 10 of these codewords into 50 qubits. But that's not right. At least two more qubits are needed for fault-tolerant error correction. So that means you could fit nine codewords into 50 qubits (since 9x5+2=47 But that's not right. There exist more efficient codes that put multiple encoded qubits into a single co…

I recently had a conversation with a Microsoft quantum researcher, and this a close approximation to his answer. I just wanted a number. It's complicated.

Re: IBM Q system in development with working 50 qubit processor

#70

Post by wmnwmn »

erikj wrote: post #45

Is this a true quantum computer? The controversy around D-Wave was confusing.

They're definitely referring to a real ("universal") quantum computer, not the quantum annealing devices of D-wave. Their computer will be able to run the Schor algorithm, if it is as advertised. If they have 20 qubits in two months, as they say they will, that seems like great progress compared to where I thought the field was. And if they have 50 within a couple years after that, it would be huge. One caveat is they seem to be making a distinction between a "universal" quantum computer, and a "universal fault-tolerant" one. Fault-tolerance requires a lot more qubits so it's not clear to me how valuable even 50 will be, if not error-corrected. I must say I will be kind of amazed if quantum computers prove to be scalable the way classical ones have been. I'm inclined to believe that the "Church-Turing" thesis will ultimately prevail once the cost of construction of the machines is factored in (~linear growth for the classical machines, greater than polynomial for the quantum). But I've been wrong before.
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