IBM Finally Proves That Quantum Systems Are Faster Than Classical Systems (engadget.com) 79
In a paper published Thursday in the journal Science, Dr. Sergey Bravyi and his team reveal that they've developed a mathematical proof which, in specific cases, illustrates the quantum algorithm's inherent computational advantages over classical. Engadget reports: "It's good to know, because results like this become parts of algorithms," Bob Sutor, vice president of IBM Q Strategy and Ecosystem, told Engadget. "They become part of decisions about how people will start to attack problems. Where will they try classical techniques? Where will they try quantum techniques? How will those interplay? How will they work back and forth together?" What's more, the proof shows that, in these cases, the quantum algorithm can solve the problem in a fixed number of steps, regardless of how many inputs are added. With a classical computer, the more inputs you add, the more steps it needs to take in order to solve. Such are the advantages of parallel processing.
"The main point of this paper is not that somehow we discover some incredibly important quantum algorithm, or some practical, interesting problem," Bravyi told Engadget. "We ask if we can separate a constant depth [between] quantum and classical algorithms. As we increase the problem size, the runtime of the quantum algorithm remains constant, but the total number of operations grows." As Bravyi points out, this new proof doesn't, in and of itself, solve any existing computational issues. Instead, "it gives us insight into what makes a quantum computers more powerful," he continued. "And hopefully in the future it will lead to more practical, useful algorithms."
"The main point of this paper is not that somehow we discover some incredibly important quantum algorithm, or some practical, interesting problem," Bravyi told Engadget. "We ask if we can separate a constant depth [between] quantum and classical algorithms. As we increase the problem size, the runtime of the quantum algorithm remains constant, but the total number of operations grows." As Bravyi points out, this new proof doesn't, in and of itself, solve any existing computational issues. Instead, "it gives us insight into what makes a quantum computers more powerful," he continued. "And hopefully in the future it will lead to more practical, useful algorithms."
Great step, practical work must follow (Score:1)
Congratulations to the IBM, this is an exciting result! Now lets just see if coherence times and the number of qubits can be scaled up as the researchers hope.
No, they did not (Score:1, Interesting)
They proved that in their mathematical model, quantum systems are faster. No mathematical model that describes physical reality accurately is known at this time though and it is known that the current standard model cannot be true as it is inconsistent. Hence they did not actually prove anything about reality.
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They proved that in their mathematical model, quantum systems are faster. No mathematical model that describes physical reality accurately is known at this time though and it is known that the current standard model cannot be true as it is inconsistent. Hence they did not actually prove anything about reality.
It disappeared in a puff of logic, then?
Don't get yourself killed at the next zebra crossing.
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What about P vs NP, or P vs EXPTIME?
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No one can ever give a practical application for any of that nonsense.
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Theoretical concepts based on a consistent theoretical axiom system. Only have approximations in reality. Anybody that really studied them knows that. All the theory here can give is hints what may or may not work in practice, it cannot do any absolute predictions.
Re:No, they did not (Score:4, Informative)
Don't worry, there is plenty of time for your traditional computers, so you can keep your job, to the point where you can retire without having to learn something new.
It is still hard to find many application developers who can code for mutable processors, let along a quantum computing model.
You don't need to go hopping up and down discrediting the scientists for their research because your job and way of life is currently still safe.
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Very well said.
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I use to build analogue simulators for power systems. effectively we built a model of the power system with capacitors, inductors and resistors on the floor of a big factory and then we use to open and close circuits or earth certain parts to simulate faults on the power grid. The cool thing taking the results instantaneously plotting them onto paper. The downside was spending ages checking the initial state of the system before you could let the simulation commence.
These days this type of simulation is
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No I didn't address the parent's argument about how the mathematical proof is useless. Because his argument isn't based on any fact, but more from an emotional response to a technology that at some point in the future could affect our way of life.
I make my living off of writing algorithms for electronic computers. If by next year we had all quantum computers which I had to program I would be at a massive disadvantage, and my many decades of experience and many thousands of dollars in education would be tos
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Indeed. But all these mindless cheerleaders do not even know what a QC can do. It is utterly pathetic.
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Wow. You really _are_ an idiot. Did anybody solve quantum-gravity while I was not looking? No? Then the standard model is still known to be wrong and you cannot actually "mathematically" prove anything about reality using it.
Incidentally, even working quantum computers are useful for very little. Almost all classical computing is not threatened, because a QC would simply be useless for it. There are a few special algorithms where a QC would do very well, but that is it. Hence there is no feeling threatened
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Indeed. And there is the little problem that QCs may never work and we may actually find out how to fix Physics instead.
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I looked ad QCs 30 years ago. They were not very useful back then and that has not changed.
Incidentally, I just added some context to the false reporting, no discrediting involved. The standard model of Physics _is_ inconsistent.
But you are obviously an idiot that compulsively cheers for the hype-du-jour.
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No mathematical model that describes physical reality accurately is known at this time though
The standard model describes reality accurately. It says electrons are perfectly spherical for example.
It is known that the current standard model cannot be true as it is inconsistent.
It doesn't have to be true to make accurate predictions. Besides, if it's inconsistent, doesn't that mean it is true (and also false)? If it was one or the other it would be consistent.
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"Besides, if it's inconsistent, doesn't that mean it is true (and also false)?"
Assuming that's a real question and not pure rhetoric, the answer is "No". It's clearly possible for two inconsistent answers to both be false. e.g. "The Earth is flat" and "The Earth is pretzel shaped."
For that matter, since we're talking about Quantum Mechanics, I doubt anyone would be shocked if two inconsistent answers are sometimes both true.
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For that matter, since we're talking about Quantum Mechanics, I doubt anyone would be shocked if two inconsistent answers are sometimes both true.
That would be incredible cool! It would mean something like observer-dependent laws of physics though and all physics would suddenly only be an approximation. That would require some major re-thinking of all theoretical physics. But given what we know about Quantum Mechanics, I would not be surprised.
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Oh? Somebody solved quantum-gravity while I was not looking? Now? Then the standard model is still known to be wrong, but nobody knows were exactly it is wrong and it is even possible that the whole thing has to be scrapped And hence you cannot prove anything "mathematically" based on it, since any mathematical proof critically requires a consistent (i.e. completely true) theory as basis. Seriously, this is proof-theory 101. Do you know nothing?
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any mathematical proof critically requires a consistent (i.e. completely true) theory as basis
Not really. Per Laplace's Rule of Succession, a completely true theory would require infinitely many (not just "many", infinitely many) data points of corroboratory evidence with exactly zero data points of falsified evidence, which isn't possible. Similarly, a completely false theory would require infinitely many data points of falsified evidence with exactly zero data points of corroboratory evidence. As such, any theory at most approaches a status of complete falseness or completely truthfulness, without
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What nonsense is that? We are talking about mathematical proofs here, not physical ones. A mathematical proof requires a consistent ("completely true") theory as a basis, period. If that is not the case, you can prove any statement that can be made in the theory to be both false and true and your theory is completely worthless.
Now, if you want a physical observation with high confidence, that is something else. But such an observation cannot be used as a starting point of mathematical deduction. Mathematica
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Mathematical proofs deals with absolute truth.
You undermine your own point. Either the "problem" is that this is a physical-mathematical proof, in which case it by definition is bounded by the uncertainties inherent in all physical theories, or it's a pure mathematical proof, in which case any reference to the actual physical world is irrelevant since it applies to a subset of all possible physics (at Tegmark level II, so not even that high), which subset may or not intersect with ours. Both cases work in opposition to your argument, which is therefore
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You wish. I just point out the problem with the story. You did summarize that nicely though.
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So, one now gets modded "troll" for accurately describing the scientific state-of-the-art? How pathetic is that?
This is good news for Quantum theorists. (Score:2, Insightful)
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Back 20+ year ago neural network was just like Quantum computing today. A few systems built around to try to prove what it could do, costing a lot of money and in general under-performing the traditional models. Now we have them on our smartphone and just used to make sure our face is ours and to place a dinosaur onto a live video feed.
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Back 20+ year ago neural network was just like Quantum computing today.
Actually: no. Neural networks are a mature "science" sind minimum 30 years.
Now we have the processing power to run/train networks like Alpha Go. But the math did not change at all. Well, the new thing is that we have dedicated hardware for ANNs and don't need to run them on a CPU or GPU.
"Quantum Systems Are Faster" (Score:1)
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very simple ones that solve trivial problems do. ones that can solve problems faster than a digital computer do not. other companies make things called "quantum annealers" that are not quantum computers.
The bad news (Score:5, Funny)
The bad news is they used quantum logic for the proof.
So the results may be true or not.
I'll stop laughing when they break some crypto.
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You mean it's both true AND false at the same time!
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I'll stop laughing when they break some crypto.
I hear they've already broken ROT-13 with this. Next in their sights is double ROT-13. Woe is me with my encrypted joke answers.
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So the results may be true or not.
Well, yes AND no.
theory == practice (Score:1)
Here's the rub: (Score:2)
... they've developed a mathematical proof which, in specific cases ...
Identifying those cases reveals that there are problems that quantum computers (QC) cannot solve and that classical computers can.
While QC will bust current encryption wide open in a New York minute, QC will also create encryption that cannot be busted.
For those interested, look at "man in the middle," wiretapping that outs itself because it's making a measurement midstream and randomizing the fuck out of the process.
For those interested (Score:2)
This is interesting because although something like Schor's algorithm for finding the order of an element in the multiplicative group of a field (and hence factoring) is faster than the best traditional algorithms, no one has actually proved that there isn't a faster method of factoring that would beat Schor.
In other words... (Score:4, Insightful)
They have demonstrated mathematically that a hypothetical quantum computer could, at least in theory, do the kind of things that have people interested in quantum computing for.
Not to detract from the mathematical achievement, the news to me at least is that this hadn't been done yet.
Not a very general result really (Score:1)
This result is extremely narrow and does not offer any generality. In the specific problems space the researchers attacked they did not find that quantum computers were better than classical computers. What they state in the paper is something far more specific and thus less powerful. The comparison is between a 2D quantum grid of 1 qubit and 2 qubit gates versus a classical (probabilistic) circuit. They found that in the classical (probabilistic) circuit there is a strong lower bound on the depth of gates