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Willow quantum chip demonstrates verifiable quantum advantage on hardware

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429 points AbhishekParmar | 2 comments | 22 Oct 25 15:16 UTC | HN request time: 0.472s | source
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andy_ppp ◴[22 Oct 25 23:11 UTC] No.45676328[source]▶
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
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vayup ◴[22 Oct 25 23:47 UTC] No.45676591[source]▶
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.

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acdha ◴[23 Oct 25 00:37 UTC] No.45676899[source]▶
I think that’s backwards: most of the stuff you mentioned is using TLS and can switch to post-quantum algorithms with a config change, and do so incrementally with no user-visible impact - e.g. right now I’m already using PQC for many sites and about half of the traffic Cloudflare sees is using PQC:

https://radar.cloudflare.com/adoption-and-usage

In contrast, cryptocurrencies have to upgrade the entire network all at once or it’s effectively a painful fork. That effort appears to just be getting talked about now, without even starting to discuss timing:

https://github.com/bitcoin/bips/pull/1895

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1. ziofill ◴[23 Oct 25 01:12 UTC] No.45677105[source]▶
Is this a purely server side migration? Do browsers/OSs need updating too?
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2. acdha ◴[23 Oct 25 02:21 UTC] No.45677471[source]▶
Clients need to be updated, too, since what's happening is that the server and client need to agree on a common algorithm they both support, but that's been in progress for years and support is now pretty widespread in the current versions of most clients.

Stragglers are a problem, of course, but that's why I thought this would be a harder problem for Bitcoin: for me to use PQC for HTTPS, only my browser and the server need to support it and past connections don't matter, whereas for a blockchain you need to upgrade the entire network to support it for new transactions _and_ have some kind of data migration for all of the existing data. I don't think that's insurmountable – Bitcoin is rather famously not as decentralized as the marketing would have you believe — but it seems like a harder level of coordination.