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The need for quantum computers remains small

theregister.com

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Re: The need for quantum computers remains small

#31

Post by bowsamic »

mtlmtlmtlmtl wrote: post #21
ramraj07 wrote: post #13

Earlier quoted context omitted.

Which side is Scott Aaranson on? Just curious.

Doesn't he work on QC from the theory side? I assume he has at least some faith if he's spending his time on it. He's on Sean Carroll's podcast talking about this stuff but I can't remember what stance he took on it. I know Stephen Wolfram isn't too excited. But I believe his issue was more that algorithms end with "and then a measurement happens", which might be quite tricky and possibly even cancel out any potentia…

Why would quantum measurement be a problem in any way? Obviously measurement doesn’t destroy quantum effects, else we would not be able to see QM in the first place. Obviously you have to factor in what the measurement does to your quantum computer, but that’s obviously just part of your design in the first place

Re: The need for quantum computers remains small

#32

Post by bowsamic »

O__________O wrote: post #17

Are quantum computers being used in economically significant ways that only are possible with quantum computers yet? If so, what is the best example? Last time I checked few years ago, my understanding was the answer was still no; specifically, believe I asked Scott Aaronson as a follow up question to a talk he gave: https://www.scottaaronson.com/

No

Re: The need for quantum computers remains small

#33

Post by mtlmtlmtlmtl »

bowsamic wrote: post #31
mtlmtlmtlmtl wrote: post #21

Earlier quoted context omitted.

Doesn't he work on QC from the theory side? I assume he has at least some faith if he's spending his time on it. He's on Sean Carroll's podcast talking about this stuff but I can't remember what stance he took on it. I know Stephen Wolfram isn't too excited. But I believe his issue was more that algorithms end with "and then a measurement happens", which might be quite tricky and possibly even cancel out any potentia…

Why would quantum measurement be a problem in any way? Obviously measurement doesn’t destroy quantum effects, else we would not be able to see QM in the first place. Obviously you have to factor in what the measurement does to your quantum computer, but that’s obviously just part of your design in the first place

I believe his point was more that the quantum measurement could very well end up costing enough time to be an issue. He didn't to into a great amount of detailed as it was mentioned more as a tangent.

Re: The need for quantum computers remains small

#34

Post by credit_guy »

LeegleechN wrote: post #26

He's not wrong about the narrow algorithmic use cases (so far), but he's completely missing the utility for simulation of quantum phenomena (chemistry, microbiology, materials science). That use case alone completely justifies investing into them even if you don't care about advancing science.

Out of curiosity, how many qubits would you need to simulate the molecule of water?

Re: The need for quantum computers remains small

#35

Post by tho2u43234 »

That's probably because "real" quantum computing today can't even factor 4-bit numbers.

The coherent-bits are really not scaling fast enough (and this is to be expected given their entanglement IMO) for anyone to really care other than snazzy startups scamming investors of their money.

Re: The need for quantum computers remains small

#36

Post by codeflo »

mtlmtlmtlmtl wrote: post #33
bowsamic wrote: post #31

Earlier quoted context omitted.

Why would quantum measurement be a problem in any way? Obviously measurement doesn’t destroy quantum effects, else we would not be able to see QM in the first place. Obviously you have to factor in what the measurement does to your quantum computer, but that’s obviously just part of your design in the first place

I believe his point was more that the quantum measurement could very well end up costing enough time to be an issue. He didn't to into a great amount of detailed as it was mentioned more as a tangent.

The sceptic arguments I read focus on accidental decoherence during the computation. If that goes well, and classical computers only "catch up" during measurement, wouldn't this mean that the time cost of measurement has to scale super-polynomially? Is that plausible?

Re: The need for quantum computers remains small

#37

Post by johnebgd »

tho2u43234 wrote: post #35

That's probably because "real" quantum computing today can't even factor 4-bit numbers. The coherent-bits are really not scaling fast enough (and this is to be expected given their entanglement IMO) for anyone to really care other than snazzy startups scamming investors of their money.

Yeah, quantum computing is still basically experimental…

Re: The need for quantum computers remains small

#38

Post by _8091149529 »

LeegleechN wrote: post #26

He's not wrong about the narrow algorithmic use cases (so far), but he's completely missing the utility for simulation of quantum phenomena (chemistry, microbiology, materials science). That use case alone completely justifies investing into them even if you don't care about advancing science.

What would be the example of an outstanding, reasonably-sized (even quantum computers of the future have finite resources) quantum simulation problem that is intractable today but would unlock some economic potential, if solved?

Re: The need for quantum computers remains small

#39

Post by zbobet2012 »

_8091149529 wrote: post #38
LeegleechN wrote: post #26

He's not wrong about the narrow algorithmic use cases (so far), but he's completely missing the utility for simulation of quantum phenomena (chemistry, microbiology, materials science). That use case alone completely justifies investing into them even if you don't care about advancing science.

What would be the example of an outstanding, reasonably-sized (even quantum computers of the future have finite resources) quantum simulation problem that is intractable today but would unlock some economic potential, if solved?

Drug molecule interactions, simulations for super conductors, etc. Etc.

Re: The need for quantum computers remains small

#40

Post by _8091149529 »

brokensegue wrote: post #20
chasil wrote: post #14

Earlier quoted context omitted.

Actually, a 65-qubit quantum computer has been created. "IBM's current largest quantum computer, revealed this month, contains 65 qubits." https://www.science.org/content/article/ibm-promises-1000-qu...

I'm not an expert but I think because of the error correction mechanisms the effective number of quibits is smaller than that

No quantum computing platform today has meaningful error correction. What you can get, in some cases, is limited error detection based on the outcome of the question computation, if it's built into your specific algorithm.
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