The need for quantum computers remains small • Hacker News Board

Re: The need for quantum computers remains small

#21

Post by mtlmtlmtlmtl » Sat, Jul 23, 2022, 4:54 AM UTC

ramraj07 wrote: post #13

dataflow wrote: post #7

Earlier quoted context omitted.

Yeah lots of people think decoherence will prevent QC from becoming practically useful. Some researchers seem to think differently, but I never found an explanation for why I should be as optimistic as they are.

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 potential gains. Not sure about the details of that, but it makes superficial sense given the nature of measurement in QM.

Re: The need for quantum computers remains small

#22

Post by denton-scratch » Sat, Jul 23, 2022, 5:19 AM UTC

rektide wrote: post #3

The need is high... for bad people doing bad things to everyone else (trying to de-secure the world)? There's some hypothetical travelling salesperson style questions we might ask. But we don't seem incapable of doing this work today. 98% the needs seem like: can we break the world's crypto. How is this anything beyond a chaotic evil mis-use? How will this do anything but de-secure & instigate risk across the planet?…

> I really struggle to understand what this all is good for.

Defence?

If your secrets (or more likely, your nation's secrets) might be exposed by a quantum attack, then you'd better understand how such an attack might work, so you can defend against it. Nations (some) do research into chemical/biological weapons to learn how to defend against them (purportedly).

That's a "devil's advocate" answer. I lean to the view that, for very big secrets, it's better not to have a secret at all. At least, don't have secrets that need to be kept long-term. That sounds glib and handwavy, and it is; but most secrets seem to get out, sooner rather than later, and usually not as a result of someone cracking the cryptography.

Re: The need for quantum computers remains small

#23

Post by reacweb » Sat, Jul 23, 2022, 5:28 AM UTC

jchw wrote: post #18

cc101 wrote: post #12

I remember when the Commodore 64 came out. "64K RAM?", I thought, "What could anyone do with so much RAM?" Power to do something new always generates new things to do with it.

You're only following the winners, but computer science has also had a lot of flops, too. Time will tell if quantum computers is one of those, but it sure isn't looking great so far.

At that time QL Sinclair was a loser. A good computer that never got programs. It was the computer of Lius Torwalds and the reason he had to write himself programs. Without QL Sinclair, we may never had Linux.

At my work, I was present when the research on ASAS (https://skybrary.aero/articles/airborne-separation-assurance...) led to the idea of PMS (https://www.eurocontrol.int/sites/default/files/2021-05/euro...).

Never underestimate serendipity

Re: The need for quantum computers remains small

#24

Post by blueprint » Sat, Jul 23, 2022, 5:32 AM UTC

No, per Susskind, we need entangled quantum computers of sufficient size to do wormhole experiments!

Re: The need for quantum computers remains small

#25

Post by rank0 » Sat, Jul 23, 2022, 5:34 AM UTC

rektide wrote: post #3

The need is high... for bad people doing bad things to everyone else (trying to de-secure the world)? There's some hypothetical travelling salesperson style questions we might ask. But we don't seem incapable of doing this work today. 98% the needs seem like: can we break the world's crypto. How is this anything beyond a chaotic evil mis-use? How will this do anything but de-secure & instigate risk across the planet?…

If you subscribe to game theory the end game means that you MUST develop this technology in case your adversaries are doing the same.

Humanity will never hold hands and sing kumbayah together.

Re: The need for quantum computers remains small

#26

Post by LeegleechN » Sat, Jul 23, 2022, 5:42 AM UTC

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.

Re: The need for quantum computers remains small

#27

Post by z3phyr » Sat, Jul 23, 2022, 5:45 AM UTC

rektide wrote: post #3

The need is high... for bad people doing bad things to everyone else (trying to de-secure the world)? There's some hypothetical travelling salesperson style questions we might ask. But we don't seem incapable of doing this work today. 98% the needs seem like: can we break the world's crypto. How is this anything beyond a chaotic evil mis-use? How will this do anything but de-secure & instigate risk across the planet?…

The need is to understand quantum systems and advance our understanding of theoretical computer science.

We do not dissuade particle physicists from performing physics because some bad people want atomic bombs; We do not dissuade Archimedes from doing his thing, for the fear of better siege engines;

Re: The need for quantum computers remains small

#28

Post by jchw » Sat, Jul 23, 2022, 5:53 AM UTC

reacweb wrote: post #23

jchw wrote: post #18

Earlier quoted context omitted.

You're only following the winners, but computer science has also had a lot of flops, too. Time will tell if quantum computers is one of those, but it sure isn't looking great so far.

At that time QL Sinclair was a loser. A good computer that never got programs. It was the computer of Lius Torwalds and the reason he had to write himself programs. Without QL Sinclair, we may never had Linux. At my work, I was present when the research on ASAS ( https://skybrary.aero/articles/airborne-separation-assurance... ) led to the idea of PMS ( https://www.eurocontrol.int/sites/default/files/2021-05/euro... )…

While that's a neat story, I'm not sure if it has a lot to do with the practical applicability of quantum computing. I didn't mean to single out Commodore or their CBM64, I really mean to say that there are plenty of examples of entire technologies that were hyped and then flopped, not just market competitors in a given technology that is already mostly proven.

Re: The need for quantum computers remains small

#29

Post by femto » Sat, Jul 23, 2022, 5:55 AM UTC

amelius wrote: post #10

rektide wrote: post #3

The need is high... for bad people doing bad things to everyone else (trying to de-secure the world)? There's some hypothetical travelling salesperson style questions we might ask. But we don't seem incapable of doing this work today. 98% the needs seem like: can we break the world's crypto. How is this anything beyond a chaotic evil mis-use? How will this do anything but de-secure & instigate risk across the planet?…

Computational chemistry (e.g. protein folding) is one useful application.

Which leads onto computational medicine.

The advent of SPICE [1] meant that with the right models electrical engineers could simulate complex electrical systems, do sensitivity analysis and make integrated circuits that had a high probability of working.

Imagine a (quantum) simulator that can rapidly simulate all or part of the human body. The effects of medicines could be rapidly simulated, or the simulation could guide the design of treatments. Eventually, if the simulation becomes as accurate as SPICE can be today, it would be possible to go directly from the design of a treatment to its administration, secure in the knowledge that it is unlikely to cause problems.

[1] https://en.wikipedia.org/wiki/SPICE

Re: The need for quantum computers remains small

#30

Post by bowsamic » Sat, Jul 23, 2022, 6:03 AM UTC

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.

Yeah the problem is in the name and the marketing. People think it is meant to replace normal computers, but that is totally wrong. The simulation use cases as well as probing fundamental physics are far more immediate and exciting