Q-Day - let's hope we're preparing for it

[dyqik]

We know what we can do, and we can do it easily. We can increase the key length on TLS RSA encryption used by webservers, and use alternative algorithms that are already built into TLS and other systems like that that are harder for quantum computers to break. Even more algorithms are already built in to libraries available to the software developers. Rolling this out will take far less time than developing quantum computers - probably less time than getting people to shift to https from http.

For high security applications, we can use quantum encryption - this will take longer to develop and roll out, but it's already in use.

Quantum computers aren't a pandemic that will go from zero to millions in a few months.

And "generative AI" hasn't really gone anywhere. What's come out is just autocomplete, with zero understanding and zero intelligence. It's good for generating spam and it's equivalents, and not much else.

[shpalman]

The point of the article is scaremongering clickbait from someone who by his own admission doesn't know what he's talking about and spends nearly half the article waffling about something else entirely in order to meet his word count.

Right now I am actually watching an online talk about quantum computing for electronic engineers.

This just got referenced: https://sam-jaques.appspot.com/quantum_landscape_2023



You can actually look at the 2021 and 2022 updates to see the progress. And then remember that the graph has logarithmic axes.

At https://quantumalgorithmzoo.org/ the first entry talks about the algorithms which would break certain kinds of encryption if you could implement them.

If you can't really see what use the other algorithms would be, well, the algorithms are there because a quantum computer would be able to do them, not because anyone needs them to be done.

[shpalman]

And this is the linear-axis version, "the distance from today's quantum computers to breaking RSA is about 10,000 chart-widths."



The 2022 update says

IBM released data from its 127-qubit Eagle processor. I have a cynical hypothesis: it wasn't quite ready to demonstrate when they announced it last year, but they had to make an announcement since they had just made their quantum roadmap in 2020, and it would look really bad to fall behind only one year after making the plan. I'm still impressed, even if it's slightly late. They have also announced a new 433-qubit chip, which I have again excluded from the chart because there is no data on qubit quality yet.

This post about Eagle from March 2022 says "IBM Quantum is committed to following our roadmap to bring a 1,121 qubit processor online by 2023" but, well, it's briefly mentioned in this press release from December 2023 while they'd prefer to talk about something apparently useful done with 127 noisy qubits in a way which wouldn't be feasible on a normal computer: Evidence for the utility of quantum computing before fault tolerance.

They simulated a physical system consisting of interacting two-level systems in a 2d network... using a quantum computer based on interacting two-level systems in a 2d network.

And here's Sabine explaining a classical simulation that is significantly more accurate and precise than the results obtained from the quantum processor.

[dyqik]

Ah, good old fashioned analog computing

[shpalman]

... a classical simulation that is significantly more accurate and precise than the results obtained from the quantum processor.

... we compute the expected value of the average single-site magnetization and show that we can obtain an accuracy of approximately
10^-14 with a simulation that runs in less than 10 s on a laptop computer...

... we obtain values of these higher weight observables to orders of magnitude better accuracy than the quantum processor with a simulation that takes less than 4 min (for these observables) to run on a laptop and a state that takes up, at most, 0.3 GB of memory.

Groups will continue to claim "quantum advantage" in solving extremely contrived problems and not long afterward someone will come up with a way of doing it on a laptop in minutes.

[jimbob]

The point of the article is scaremongering clickbait from someone who by his own admission doesn't know what he's talking about and spends nearly half the article waffling about something else entirely in order to meet his word count.

Right now I am actually watching an online talk about quantum computing for electronic engineers.

This just got referenced: https://sam-jaques.appspot.com/quantum_landscape_2023



You can actually look at the 2021 and 2022 updates to see the progress. And then remember that the graph has logarithmic axes.

At https://quantumalgorithmzoo.org/ the first entry talks about the algorithms which would break certain kinds of encryption if you could implement them.

If you can't really see what use the other algorithms would be, well, the algorithms are there because a quantum computer would be able to do them, not because anyone needs them to be done.

What does "surface codes work" mean in this context?

[shpalman]

A surface code is an encoding of a qubit states in a two-dimensional grid of physical qubits. Beyond that I don't really know what's going on with surface codes, maybe I have the recording of the IBM lecture which mentions them. Maybe that ESRF lecture I linked to above has something about them.

[shpalman]

... a classical simulation that is significantly more accurate and precise than the results obtained from the quantum processor.

... we compute the expected value of the average single-site magnetization and show that we can obtain an accuracy of approximately
10^-14 with a simulation that runs in less than 10 s on a laptop computer...

... we obtain values of these higher weight observables to orders of magnitude better accuracy than the quantum processor with a simulation that takes less than 4 min (for these observables) to run on a laptop and a state that takes up, at most, 0.3 GB of memory.

Groups will continue to claim "quantum advantage" in solving extremely contrived problems and not long afterward someone will come up with a way of doing it on a laptop in minutes.

Or on a Commodore 64.

https://www.tomshardware.com/tech-indus ... y-accurate