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IBM Finally Proves That Quantum Systems Are Faster Than Classical Systems (engadget.com)
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."
A researcher hypothesized that as quantum systems grew in complexity, the amount of noise they experience grows exponentially. This is problematic because noise decoheres the system, limiting the complexity of the computations that can be performed and result in an answer without having to rerun the calculation to discover a consensus. This was based on experience of the performance of existing systems.
Has the noise problem been solved yet?
Jesus, it's not even clear any longer what message you trolls want to convey. Online trolling has become like the test spam I get, with empty mail body or full of incomprehensible garbage. Come on, show some effort! Troll harder!
Maybe some of the trolling is actually neural net encoded secret messages between terrorist cells. 8-)
It's been proven that this is a great way to encode messages - spam forums with encoded message, spew garbage while passing their messages surreptitiously. Most laymen would only see garbage and spam while the rest would actually get trolled.
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.
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.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
The money will keep flowing. Now build something out here in reality that actually does something useful.
Kevin Roach, an IBM ambassador and chairman of WorldCon 76 San Jose 2018, gave a presentation on the current state of quantum computing. He was asked how fast the interconnect speed was between the different components, his response was 100 nanoseconds. IIRC, 1970's through-hole chip technology was faster.
ibm-finally-proves-that-quantum-systems-are-faster-than-classical-systems
should be
ibm-finally-proves-that-quantum-systems-{will be}-faster-than-classical-systems-{if we can build them}
It seems that most quantum articles these days feel this way.
Come on guys, the interesting thing about quantum computing is not that it will be useful.
It is if and when it will be.
Do quantum computers exist?
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.
"we are all atheists about most of the gods that societies have ever believed in. Some of us just go one god further."
Nah, IBM has built a quantum computer, did you see them sell it? No. Yet if it has such an advantage then why not make and sell them? They built it after EU promised 1 billion euros to kickstart quantum computing in Europe. It was a play to obtain that free cash. It's an analogue computer. Here they propose a specific function that an analogue computer with specific properties would solve quicker than a sequential digital computer "composed of fan-in gates"...
Meanwhile, deep neural network hardware is built into smartphones now. One of those is a real computational thing, and the other is smoke and mirrors designed to fool politicians.
"we introduce a non-oracular version of the Bernstein-Vazirani problem which we call the 2D Hidden Linear Function problem. An instance of the problem is specified by a quadratic form q that maps n-bit strings to integers modulo four. The goal is to identify a linear boolean function which describes the action of q on a certain subset of n-bit strings. We prove that any classical probabilistic circuit composed of bounded fan-in gates that solves the 2D Hidden Linear Function problem with high probability must have depth logarithmic in n. In contrast, we show that this problem can be solved with certainty by a constant-depth quantum circuit composed of one- and two-qubit gates acting locally on a two-dimensional grid. "
in theory. In practice however they differ.
They aren't comparing classical and quantum computing to ISIS's posts? ISIS had 100s of algorithms all spamming terrorist propaganda 24/7 basically Obama's whole second term. Can we get a comparison of THAT? Started around 2013 when John Brennan became CIA director, and ended around 2017 when Trump took over and replaced Brennan with Pompeo.
I can prove that Transwarp drive is faster than warp drive, but that still doesn't make it real.
The entire problem behind this is it's built on the idea that Quantium mechanics is real, that particles are real, that Einstein was right. But all those are THEORY, unproven.
There is mounting evidence that Einstein was just wrong, and if that is the case, then all this is moot.
you know it's fucking bunk.
If this would just make annealing faster or reversing some large prime factors ... I don't care.
QPU(Quantum Processing Unit)
The hot grits are poured down petrified pants at midnight.
... 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.
It little behooves the best of us to comment on the rest of us.
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.
"What lies behind us, and what lies before us are tiny matters compared to what lies within us." Ralph Waldo Emerson
[...]
In what’s now an extremely familiar pattern, this paper appeared on the arXiv a year and a half ago, and was a highlight of the QIP conference in January. So it’s already been assimilated by people in the field and there’s even been followup work. But then it gets officially published in Science, which leads to garbled popular articles about the brand-new earth-shattering breakthrough, and only by clicking the link to the paper do you learn that that breaking news and the thing that was really nice when you digested it last year are one and the same.
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.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
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 required to solve the problem (log n, where n is the size of the input). In the quantum grid case the depth remains constant as the computation is carried out over a 2D quantum grid.
Both Science and other write ups about this result, including this post, seems to paint this result very generally and it simply isn't. It's not an algorithm, the paper does not pit quantum vs classical computers, simply circuits. There is no analysis as to the size of the quantum grid required w.r.t. the size of the input, only the depth of the circuit. Also by leaning on probabilistic classical circuits they move the goalposts into an exotically small portion of the problem space.
The result is rather great, but it is nothing like the media is portraying and it is not a general result at all. Please don't take the above as anything other than media critique and clarification of the results in the paper.