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Google claims to have proved its supremacy with new quantum computer

telegraph.co.uk

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Re: Google claims to have proved its supremacy with new quantum computer

#221

Post by hcks »

laxd wrote: post #127
tedivm wrote: post #22

Earlier quoted context omitted.

I don't think it's that the concepts are contrived (although the test cases certainly are), it's just that our quantum computers are really early in their development and can't do the more complicated things yet. It's like if we had calculators that took an hour to do each arithmetic operation- the fact that people wouldn't use it doesn't mean arithmetic is contrived, just that it isn't as powerful as better alternat…

> ... quantum computers are really early in their development and can't do the more complicated things yet. It's like if we had calculators that took an hour to do each arithmetic operation ... Reminds me of the story George Stibitz tells after developing one of the first devices that could be called a computer. Management at Bell Labs was not impressed that he had built a "20000 dollar calculator". https://youtu.be/…

Well a “20000 dollar calculator” is something QC can only dream of

Re: Google claims to have proved its supremacy with new quantum computer

#222

Post by MattPalmer1086 »

skywhopper wrote: post #172
hedora wrote: post #130

Earlier quoted context omitted.

Well, in fairness, I could say the same about solar, improved batteries, etc.

Solar has become incredibly inexpensive in the last decade, and batteries likewise are many times better than they were 20 years ago. Is there further to go, yes, but progress has been steady and real applications are all around you for both. Our phones are marvels of battery technology that was impossible 15 years ago. Fusion and quantum computing on the other hand. Neither has yet solved one problem or made net pro…

You think there has been no net progress in QC or fusion? There has been a lot of progress, but not to the point where we can make practical use of them yet.

Some problems are just harder than others. Maybe some of them are not soluble, or some are not economic. We won't know if we don't try, and they hold out great promise.

Re: Google claims to have proved its supremacy with new quantum computer

#223

Post by bawolff »

hcks wrote: post #219
bawolff wrote: post #191

Earlier quoted context omitted.

I don't think that is true, i imagine most people thought it was much more than 10 years away 30 years ago. I think 30 years ago people still weren't sure if it was physically possible at all. In the mean time real progress has been made. If we continue at this rate (big if) we will eventually have quantum computers. Just not tomorrow.

I’m curious, what “real progress” did QC make since the 90s?

While they said 30 years ago, so since 1993?

On the theoretical side shor's algorithm was invented 29 years ago, which is what started the hype in the first place. 30 years ago is 1 year before anyone really cared.

Late 90s early 2000s you start to see progress on quantum error correction, which is key progress neccessary to make this all work theoretically

Starting Mid-2000s you start to see toy realization proof of concepts (devices with a few qubits). Thdy aren't very useful but realizing a physical device is the first step to doing anything at all. These keep getting better and better.

Early 2020s you start to see devices that can perform computation, that well not particularly useful, are complex enough that they would require a super computer to do clasically. This in my opinion is quantum computer's "hello world" moment in my opinion. Writing a hello world program is still very far off from say writing the linux kernel, but its the step where things get real.

Like most things in science, most of this is not zOMG breakthrough, but small gains compounding over time to create real progress.

Re: Google claims to have proved its supremacy with new quantum computer

#224

Post by bawolff »

pclmulqdq wrote: post #209
erikaww wrote: post #177

Earlier quoted context omitted.

I'm not educated on QC. But wouldn't Grover's algorithm be very useful? I believe it provides a sqrt(n) time search. For QC to be useful,it just needs to make common utilities very fast. I should look more into QC. It would be cool if it could speed all computation up. I understand there are algorithms that it could execute that a classical composer could not, but I wonder if it could eventually he like just faster h…

To load those bits into your quantum computer, you need to spend O(n) time. Most practical searches are O(n).

Not neccesarily, you can calculate them on the fly.

Re: Google claims to have proved its supremacy with new quantum computer

#225

Post by mistermann »

gopher_space wrote: post #204
Dylan16807 wrote: post #176

Earlier quoted context omitted.

> And when it gets noticed, sometimes really weird things happen. ....such as? If you have any proof you can probably get a nobel prize.

I was thinking op meant something like realizing everyone has their own take on NULL and none of them are really wrong or right.

This is pretty close...although some can be correct, but correctness is not necessarily justified (such as when guessing what "is probably" true, which is why the J in JTB exists, and perhaps also because people like to take the T for free, as doing otherwise "is pedantic", which almost always has consensus agreement - reality domes don't maintain themselves!!).

Re: Google claims to have proved its supremacy with new quantum computer

#226

Post by mistermann »

Dylan16807 wrote: post #205
mistermann wrote: post #194

Earlier quoted context omitted.

Everyone "already knows" these things, so no awards or even surprise awaits one.

If you can change bits that have already been observed, that would be very surprising to people. Otherwise I'm not sure what you mean by "generate" but almost any kind of influence would have massive potential.

Surprising to some, pleasing to others, infuriating to others. But to those who have mastery over it: powerful.

Re: Google claims to have proved its supremacy with new quantum computer

#227

Post by cevi »

DLA wrote: post #131

Can anyone recommend a few videos, papers, or books that "start at the beginning" for how quantum computing works--the physics parts like entanglement. I'm a computer scientist, so I'm good with the algorithm/programming aspects. Should I start with quantum annealing? Ideally I guess I'd like some pointers to good approachable resources on the ways qubits are made, maintained, written to and read from--start me off a…

This may be a bit on the theoretical side, but it's the best reference for quickly getting up to speed on how quantum computing and entanglement works that I know of: https://cs.uwaterloo.ca/~watrous/QC-notes/QC-notes.pdf

As for how actual physical qubits are maintained, that topic is tough to find a good explainer for, since every group has a different approach. Some groups use trapped ions, some use two-dimensional quasiparticles, some use spin states of photons... and no one has a clue which approach will be most practical in the end. It's analogous to not knowing whether clockwork or vacuum tubes will be the better way to implement a Turing machine.

Re: Google claims to have proved its supremacy with new quantum computer

#228

Post by Dylan16807 »

mistermann wrote: post #225
gopher_space wrote: post #204

Earlier quoted context omitted.

I was thinking op meant something like realizing everyone has their own take on NULL and none of them are really wrong or right.

This is pretty close...although some can be correct, but correctness is not necessarily justified (such as when guessing what "is probably" true, which is why the J in JTB exists, and perhaps also because people like to take the T for free, as doing otherwise "is pedantic", which almost always has consensus agreement - reality domes don't maintain themselves!!).

But where does the quantum come in? You don't need it to have/manipulate consensus.

What are the "weird things"?

Re: Google claims to have proved its supremacy with new quantum computer

#229

Post by dataflow »

jabbany wrote: post #199
dataflow wrote: post #89

Earlier quoted context omitted.

I really love this comment -- it "feels" like the right criterion -- but I guess I'm wondering what criteria (if any) researchers actually use right now. Do they have any criteria for this?

I'm not a quantum computing researcher but I have friends who work on it. The way they've described this to me (answering a question around "how does one know what quantum stuff is bs") was that it's largely a set of known "hard" questions where we've empirically found hard for classical computing but we maybe could solve with quantum. In a way it's been described as similar to crypto primitives or P?=NP problems whe…

> where we've empirically found hard for classical computing but we maybe could solve with quantum

Are we talking complexity classes here, or just "problems we've found hard in practice, but that which may in fact be in P even if P != NP"?

Like I would've thought that solving BQP problems like integer factorization would be the criterion (since they're proven to be faster under QC assuming P != NP etc.). But that's evidently the researchers aren't holding themselves up to that standard, so what bar are they using exactly? Are they just going with some sort of "if it walks like a duck then it's a duck" criterion, or are they using problems that they can formally prove lack efficient classical solutions under a well-regarded hypothesis like P != NP?

Re: Google claims to have proved its supremacy with new quantum computer

#230

Post by mistermann »

Dylan16807 wrote: post #228
mistermann wrote: post #225

Earlier quoted context omitted.

This is pretty close...although some can be correct, but correctness is not necessarily justified (such as when guessing what "is probably" true, which is why the J in JTB exists, and perhaps also because people like to take the T for free, as doing otherwise "is pedantic", which almost always has consensus agreement - reality domes don't maintain themselves!!).

But where does the quantum come in? You don't need it to have/manipulate consensus. What are the "weird things"?

> But where does the quantum come in?

My thinking is here:

https://en.m.wikipedia.org/wiki/Quantum_superposition

> You don't need it to have/manipulate consensus.

Right, it's obliviousness to (or ideological, indoctrinated denial of) the phenomenon of extra variables/state that enables the manipulation of consensus. (I'm looking at you, scientists.)

Also, if these higher states did not exist, I'd think the problem might be either be impossible in the first place, or impossible to detect. (Noteworthy: having flawed methodologies can also make them impossible to detect.)

> What are the "weird things"?

Hallucination is the most obvious, but I would also say: just look around!

Or for a more serious analysis:

https://slatestarcodex.com/2014/07/30/meditations-on-moloch/

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