Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

IBM unveils 127-qubit quantum processor

newsroom.ibm.com

Post reply on HN
Print view View original

121–130 of 325 posts

Re: IBM unveils 127-qubit quantum processor

#121

Post by krylon »

rain1 wrote: post #60

It is incredibly dishonest of them to post this without any details about the noise parameters of the system. When reading "127-qubit system" you would expect that you can perform arbitrary quantum computations on these 127 qubits and they would reasonably cohere for at least a few quantum gates. In reality the noise levels are so strong that you can essentially do nothing with them except get random noise results. M…

    > The omission of proper technical details is essentially the same as lying.
Welcome, child, to the beautiful/"special" world of marketing!

Re: IBM unveils 127-qubit quantum processor

#122

Post by rbanffy »

jjoonathan wrote: post #47
krastanov wrote: post #37

Earlier quoted context omitted.

The pipes you mentioned are microwave conduits (for various control signals).

0.141" semi-rigid coax, diameter of champions.

> 0.141" semi-rigid coax, diameter of champions.

I wonder if we measure it more precisely we'll get to something closer to 1.4142135623730950488...

Re: IBM unveils 127-qubit quantum processor

#123

Post by robin_reala »

cashsterling wrote: post #71
krastanov wrote: post #55

Earlier quoted context omitted.

It is even worse than single digit Kelvin. Liquid Nitrogen with pumping: 40 K for a few thousand dollars. Run of the mill Liquid Helium: 4 K for tens to hundreds of thousands of dollars. But for these devices you need 15mK which is reachable only if you mix two different isotopes of Helium and pump the mixture into vacuum. Such a device is up to 1M$ and more. And the insides of that device are in vacuum (actually, ai…

FWIW... small DR's are under 400k USD. The big ones are ~1M USD or more.

What’s a DR? Something refrigerator?

Re: IBM unveils 127-qubit quantum processor

#124

Post by haltingproblem »

Obligatory PSA: Scott Locklin's "Quantum computing as a field is obvious bullshit":

"When I say Quantum Computing is a bullshit field, I don’t mean everything in the field is bullshit, though to first order, this appears to be approximately true. I don’t have a mathematical proof that Quantum Computing isn’t at least theoretically possible. I also do not have a mathematical proof that we can or can’t make the artificial bacteria of K. Eric Drexler’s nanotech fantasies. Yet, I know both fields are bullshit. Both fields involve forming new kinds of matter that we haven’t the slightest idea how to construct. Neither field has a sane ‘first step’ to make their large claims true.

.....

“quantum computing” enthusiasts expect you to overlook the fact that they haven’t a clue as to how to build and manipulate quantum coherent forms of matter necessary to achieve quantum computation. A quantum computer capable of truly factoring the number 21 is missing in action. In fact, the factoring of the number 15 into 3 and 5 is a bit of a parlour trick, as they design the experiment while knowing the answer, thus leaving out the gates required if we didn’t know how to factor 15. The actual number of gates needed to factor a n-bit number is 72 x n^3; so for 15, it’s 4 bits, 4608 gates; not happening any time soon".

[1]: https://scottlocklin.wordpress.com/2019/01/15/quantum-comput...

Re: IBM unveils 127-qubit quantum processor

#125

Post by kingcharles »

paxys wrote: post #107
RivieraKid wrote: post #86

Tangential question, what are the areas of technology where we can expect to see substantial progress or breakthroughs within 2030, i.e. what are the most exciting areas to follow and look forward to? Here's my list: - Nuclear fusion (Helion, ZAP, TAE, Tokamak Energy, CFS, Wendelstein). - Self-driving cars. - New types of nuclear fission reactors. - Spaceflight (SpaceX Starship). - Supersonic airplanes (Boom). - Soli…

Sadly I'd also qualify most of these as things that consumers are overly excited about but will never reach their expected potential (at least in our lifetimes) due to technological limits. Same as flying cars, 3D TVs, 3D printing, household robots, holograms, AR glasses.

3D TVs will come of age once autostereoscopic displays reach the right level of quality. After being blown away by my first glimpse of a display in around 1998 I fully expected them to be useable years ago. I guess we might still be another "10 years" away.

https://en.wikipedia.org/wiki/Autostereoscopy

Re: IBM unveils 127-qubit quantum processor

#127

Post by tcgv »

bnjemian wrote: post #104
tcgv wrote: post #95

Earlier quoted context omitted.

Roughly, computational power = number of operations per cycle. Classical computers can only perform a number of operations per cycle linearly proportional to the amount of hardware architecture available (ex: one core, two cores, quad-core). Quantum computers can take advantage of superposition and entanglement to, given some restrictions, perform multiple operations per cycle, proportional to "two" to the power of t…

That's not quite it. The power of a QC comes from modeling an exponentially large probabilistic state space using entanglement and superposition. The operations performed by a QC are also different, they can be analog (arbitrary rotations), but circuit depths (i.e. the number of operations) are still expected to be polynomial. The difference is that the probabilistic state space uses probability amplitudes, which are…

Thanks for detailing. I was explaining in laymen terms, using less technical details, with some reservations ("roughly" and "given some restrictions").

> Orchestrate the right kind of interference, and for some problems, you have an algorithm that outputs a solution to that problem with (relatively high probability) in time that, depending on the problem, may be exponentially faster.

Exactly. Given some restrictions, it's possible to implement algorithms that are equivalent to performing an exponentially large amount of classical operations per "cycle".

> Examples of those problems include prime factorization/discrete logarithms (Shor's algorithm)

Indeed. I provide an implementation of the Deutsch–Jozsa algorithm [1][2] based in my own quantum computing simulator that I linked in my blog post (in the original comment) to address this.

[1] https://en.wikipedia.org/wiki/Deutsch%E2%80%93Jozsa_algorith...

[2] https://github.com/TCGV/QuantumSim/blob/master/Tcgv.QuantumS...

Re: IBM unveils 127-qubit quantum processor

#128

Post by tlrobinson »

gfodor wrote: post #113
RivieraKid wrote: post #86

Tangential question, what are the areas of technology where we can expect to see substantial progress or breakthroughs within 2030, i.e. what are the most exciting areas to follow and look forward to? Here's my list: - Nuclear fusion (Helion, ZAP, TAE, Tokamak Energy, CFS, Wendelstein). - Self-driving cars. - New types of nuclear fission reactors. - Spaceflight (SpaceX Starship). - Supersonic airplanes (Boom). - Soli…

- Psychadelics - VR/AR (photonic override, more specifically) - Fundamental physics (unlocked by tech)

Can you elaborate on “photonic override”? Googling that phrase pretty much just returns more HN comments and tweets by you :)

Re: IBM unveils 127-qubit quantum processor

#129

Post by bnjemian »

littlestymaar wrote: post #89
andrewla wrote: post #81

Earlier quoted context omitted.

Basically little more than having a bathtub and claiming you've built a computer that does 600e23 node fluid dynamic calculations. But a lot more expensive.

I haven't read anything on this one yet, but your analogy fits Google's “quantum supremacy” paper really well, I likes it.

Ugh, the point is a fine one but it appears it has to be made:

Validation of experimental theory through the characterization and control of an entire system is not the same as building the same system and simply seeing the final state is what you expect. The latter is much easier and says very little about your understanding.

Here's an analogy: Two people can get drunk, shack up for the night, and 9 months later have created one of the most powerful known computers: A brain. Oops. On the flip, it's unlikely we'll have a full characterization and understanding of the human brain in our lifetimes – but if we ever do, the things we'll be able to do with that understanding will very likely be profound.

Re: IBM unveils 127-qubit quantum processor

#130

Post by nixpulvis »

newsbinator wrote: post #98
jazzyjackson wrote: post #33

Quantum Computers sitting in their cryogenic chambers are such works of art, stacks of giant brass plates and hundreds of heat pipes (or coolant pipes? liquid helium I suppose) twisted and coiling throughout the structure hanging like some steampunk chandelier (why do they hang from above anyway?) EDIT: changed to a few direct links to pics: [0][1][2] The esoteric design reminds me of the Connection Machine blog post…

Someday when quantum computers are the size of dust particles and we're surrounded by them there'll be some version of a steampunk subculture that values decorating their homes with these ancient beautiful and laughably incapable devices. Maybe in 30 ~ 50 years or so.

I can't help but think of turning them into horrible sounding organs.
Post reply on HN