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Willow quantum chip demonstrates verifiable quantum advantage on hardware

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Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#221

Post by dweekly »

qnleigh wrote: post #203
andy_ppp wrote: post #178

I would be quite worried about advances in quantum computers if I had any Bitcoin after watching this DEFCON talk: https://www.youtube.com/watch?v=OkVYJx1iLNs

The quantum algorithm that would break certain kinds of public key cryptography schemes (not even the core part of Bitcoin blockchains, which are not vulnerable to quantum computers) will take days to weeks to break a single key [0]. This is another reason why we will have plenty of warning before quantum computing causes any major disruptions to daily life. What I would start worrying about is the security of things…

Meta has been rolling out PQC: https://engineering.fb.com/2024/05/22/security/post-quantum-...

And Apple: https://security.apple.com/blog/imessage-pq3/

Cloudflare started rolling it out three years ago! https://developers.cloudflare.com/ssl/post-quantum-cryptogra...

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#222

Post by vayup »

irjustin wrote: post #218
vayup wrote: post #183

Earlier quoted context omitted.

Quantum is a known threat. There is enough time to fix it. Folks are working on the fixes. Cryptocurrencies would be the last thing I worry about w.r.t Quantum crypto attacks. Everything would be broken. Think banks, brokerage accounts, email, text messages - everything.

> Everything would be broken. Think banks, brokerage accounts, email, text messages - everything. Wonder if this would become the next "nuclear proliferation". Since it's so hard to manufacture it gets controlled at state level and then becomes a technology that the general public are never allowed to have.

No, it is a known problem. It will get fixed in time.

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#223

Post by cubic_prism »

strbean wrote: post #103
jwpapi wrote: post #84

Earlier quoted context omitted.

Not even needed you can just copy network state of a specific moment in time and encrypt with a new algorithm that will be used from then on

The problem is that the owner needs to claim their wallet and migrate it to the new encryption. Just freezing the state at a specific moment doesn't help; to claim the wallet in the new system I just need the private key for the old wallet (as that's the sole way to prove ownership). In our hypothetical post-quantum scenario, anyone with a quantum computer can get the private key and migrate the wallet, becoming the…

Note, the 126 billion Toffoli gates are operations, so that's more about how many operations you need to be able to reliably apply without error.

It should be noted that according to IonQ's roadmap, they're targeting 2030 for computers capable of that. That's only about 5 years sooner than when the government has said everyone has to move to post quantum.

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#227

Post by zingar »

nine_k wrote: post #132
cluckindan wrote: post #128

Earlier quoted context omitted.

They haven’t, though?

At least they claim that: «Quantum verifiability means the result can be repeated on our quantum computer — or any other of the same caliber — to get the same answer, confirming the result. This repeatable, beyond-classical computation is the basis for scalable verification.» (emph. mine) But apparently they haven't demonstrated the actual portability between two different quantum computers.

What’s the difference between the claim that they’re making and what you say they haven’t done?

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#228

Post by [deleted] »

nicce wrote: post #153
jonathanstrange wrote: post #32

Earlier quoted context omitted.

The article states: “...13,000 times faster on Willow than the best classical algorithm on one of the world’s fastest supercomputers...” I agree it's not very precise without knowing which of the world's fastest supercomputers they're talking about, but there was no need to leave out this tidbit.

I don’t understand how these papers get accepted

[deleted]

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#229

Post by csnweb »

DrNosferatu wrote: post #126

I would like to hear from the classical computation people if they validate these results and claims: As many times in the past quantum supremacy was claimed, and then, other groups have shown they can do better with optimized classical methods.

That might take a few days or weeks, it seems like they put in some decent effort into it this time. From skimming the supplement I wouldn’t be suprised if the speedup is only 100x though. That’s still significant, but clearly less than they claim. For example I am not entirely convinced that 20% flops efficiency is really the upper limit or that the slicing overhead of 5x is really needed here.

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#230

Post by qnleigh »

gsf_emergency_4 wrote: post #219

Why use the subtext? In the peer review (pp30-31), the authors > acknowledge [that] Hamiltonian learning of an actual physical system has not been performed [and] have therefore further de-emphasized the quantum advantage claim in the revised manuscript https://static-content.springer.com/esm/art%3A10.1038%2Fs415...

This excerpt misses the wider point of the paper. The paragraph immediately following the one you quote still does make claims of quantum advantage:

"Our second order OTOC circuits introduce a minimal structure while remaining sufficiently generic that circumvents this challenge by exploiting the exponential advantage provided by including time inversion in the measurement protocol, see arXiv:2407.07754."

The advantage claimed by the paper isn't about Hamiltonian learning (i.e extracting model parameters from observational data), but instead about computing the expectation value of a particular observable. They acknowledge that the advantage isn't provable (even the advantage of Shor's algorithm isn't provable), but they argue that there likely is an advantage.

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