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Willow, Our Quantum Chip

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151–160 of 557 posts

Re: Willow, Our Quantum Chip

#151

We need to seriously think if our systems/society are even remotely ready for this.

As if "thinking about it" will ever stop people from acting first. I'm far more scared when tech-bros like Musk land on Mars and contaminate stuff we might not even be able to detect yet.

i'm not even remotely 'far more scared' about that. i think you are insufficiently scared about crypto being broken

Re: Willow, Our Quantum Chip

#152

Imagine your civilization develops quantum computing technology and it's for... advertising. "What is their mission? Cure cancer? Eliminate poverty? Explore the universe? No, their goal: to sell another fucking Nissan." --Scott Galloway

That's how you monetize attention, digital consumption. If you aren't paying for it, you are the product being sold.

Re: Willow, Our Quantum Chip

#153

Earlier quoted context omitted.

not metaphysically equivalent. also, i’m not so certain it will always be untestable. i would have thought the same thing about hidden variables but i underestimated the cleverness of experimentalists

I think "experimentally equivalent" is what GP meant, and as of today, it holds true. Google's results are predicted by other interpretations just as well as by Everett. Maybe someday there will be a clever experiment to distinguish the models but just "we have a good QC" is not that.

i think you're arguing against a point i never made in any of my comments

Re: Willow, Our Quantum Chip

#154

Earlier quoted context omitted.

In my opinion the "shut up and calculate" view is the most common among actual quantum computing researchers. Unsure about those working on quantum foundations, but I think the absence of consensus is enough to claim any view as absolutely not the view.

i don’t really view “shut up and calculate” or very restrained copenhagenism as a real view at all. i think if you were to ask people to make a real metaphysical speculation, majority might be partial to everett - especially if they felt confident the results were anonymous

I agree, but that kind of goes to my point:

I believe the vast majority of researchers in quantum computing* spend almost no time on metaphysical speculation,

*Well, those on the "practical side" that thinks about algorithms and engineering quantum systems like the Google Quantum AI team and others. Not the computer science theorists knee-deep in quantum computational complexity proofs nor physics theorists working on foundations of quantum mechanics. But these last two categories are outnumbered by the "practical" side.

Re: Willow, Our Quantum Chip

#155

I’m a quantum dabbler so I’ll throw out an armchair reaction: this is a significant announcement. My memory is that 256 bit keys in non quantum resistant algos need something like 2500 qubits or so; and by that I mean generally useful programmable qubits. To show a bit over 100 qubits with stability, meaning the information survives a while, long enough to be read, and general enough to run some benchmarks on is some…

How can I, a regular software engineer, learn about quantum computing without having to learn quantum theory? > Worth spending a little time doing some long tail strategizing I’d say any tips for starters?

First learn about eigenvalues.

Re: Willow, Our Quantum Chip

#156
post #71

I’m a quantum dabbler so I’ll throw out an armchair reaction: this is a significant announcement. My memory is that 256 bit keys in non quantum resistant algos need something like 2500 qubits or so; and by that I mean generally useful programmable qubits. To show a bit over 100 qubits with stability, meaning the information survives a while, long enough to be read, and general enough to run some benchmarks on is some…

The error rates given are still horrendous and nowhere near low enough for the Quantum Fourier Transform used by Shor's algorithm. Taking qubit connectivity into account, a single CX between 2 qubits that are 10 edges aways gives an error rate of 1.5%. Also, the more qubits you have/the more instructions are in your program, the faster the quantum state collapses. Exponentially so. Qubit connectivity is still ridicul…

Re: AI, it's a long way off still. The big limitation to anything quantum is always going to be decoherence and t-time [0]. To do anything with ML, you'll need whole circuit (more complex than shor's) just to initialize the data on the quantum device; the algorithms to do this are complex (exponential) [1]. So, you have to run a very expensive data-initialization circuit, and only then can you start to run your ML circuit. All of this needs to be done within the machine's t-time limit. If you exceed that limit, then the measured state of a qubit will have more to do with outside-world interactions than interactions with your quantum gates.

Google's willow chip has t-times of about 60-100mu.s. That's not an impressive figure -- in 2022, IBM announced their Eagle chip with t-times of around 400mu.s [2]. Google's angle here would be the error correction (EC).

The following portion from Google's announcement seems most important:

> With 105 qubits, Willow now has best-in-class performance across the two system benchmarks discussed above: quantum error correction and random circuit sampling. Such algorithmic benchmarks are the best way to measure overall chip performance. Other more specific performance metrics are also important; for example, our T1 times, which measure how long qubits can retain an excitation — the key quantum computational resource — are now approaching 100 µs (microseconds). This is an impressive ~5x improvement over our previous generation of chips.

Again, as they lead with, their focus here is on error correction. I'm not sure how their results compare to competitors, but it sounds like they consider that to be the biggest win of the project. The RCS metric is interesting, but RCS has no (known) practical applications (though it is a common benchmark). Their T-times are an improvement over older Google chips, but not industry-leading.

I'm curious if EC can mitigate the sub-par decoherence times.

[0]: https://www.science.org/doi/abs/10.1126/science.270.5242.163...

[1]: https://dl.acm.org/doi/abs/10.5555/3511065.3511068

[2]: https://www.ibm.com/quantum/blog/eagle-quantum-processor-per...

Re: Willow, Our Quantum Chip

#157

Earlier quoted context omitted.

No, that's not what that means. Not sure what you mean by the "that" when you say "if that's true", but there is nothing in this thread or by google that is anywhere close to breaking encryption.

How are you so sure? If something that takes years is completed in minutes, how is encryption safe?

The amount of cubits required for a practical application of shors algorithm to break modern encryption is known and it's around 2500 qubits

Willow has 100

Re: Willow, Our Quantum Chip

#158

Earlier quoted context omitted.

You've mentioned this in another comment. I have to point out, even if this is his opinion, and he has been influential in the field, it does not mean that this specific idea of his has been influential.

Sorry. I don't care whether an idea was influential or not. All I care is whether someone has a better explanation.

I'll remind you of the quote that started this thread:

"Do quantum computing folks really think that we are borrowing capacity from other universes for these calculations?"

In this context, your opinion and Deutsch's opinion don't matter. The question is about whether the idea is common in the field or not.

Re: Willow, Our Quantum Chip

#159
post #88

Earlier quoted context omitted.

I recommend this book I studied it in Undergrad and I never took a quantum theory course. https://www.amazon.com/Quantum-Computing-Computer-Scientists...

Are there any insights that you can give based off the info you've learned about quantum computation that you might not have been able to reach if you hadn't learned about it? From my __very__ shallow understanding, because all of the efficiency increases are in very specific areas, it might not be useful for the average computer science interested individual?

Nearly all of quantum computation is theoretical algorithms and the hard engineering problems haven't been solved. Most of the math though has a large amount of overlap of AI / ML and all of deep learning to the point that Quantum computers could be used as "ML accelerators" by using algorithms (this is called Quantum Machine learning) [1]. Quantum computing could be learned with a limited understanding of Quantum theory unless you are trying to engineer the hardware.

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

Re: Willow, Our Quantum Chip

#160
post #8

> It lends credence to the notion that quantum computation occurs in many parallel universes, in line with the idea that we live in a multiverse I see the evidence, and I see the conclusion, but there's a lot of ellipses between the evidence and the conclusion. Do quantum computing folks really think that we are borrowing capacity from other universes for these calculations?

Everett interpretation simply asserts that quantum wavefunctions are real and there's no such thing as "wavefunction collapse". It's the simplest interpretation.

People call it "many worlds" because we can interact only with a tiny fraction of the wavefunction at a time, i.e. other "branches" which are practically out of reach might be considered "parallel universes".

But it would be more correct to say that it's just one universe which is much more complex than what it looks like to our eyes. Quantum computers are able to tap into this complexity. They make a more complete use of the universe we are in.

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