Willow quantum chip demonstrates verifiable quantum advantage on hardware

As with any quantum computing news, I will wait for Scott Aaronson to tell me what to think about this.

Why wait? Just go read the paper:

https://www.nature.com/articles/s41586-025-09526-6

In the last sentence of the abstract you will find:

"These results ... indicate a viable path to practical quantum advantage."

And in the conclusions:

"Although the random circuits used in the dynamic learning demonstration remain a toy model for Hamiltonians that are of practical relevance, the scheme is readily applicable to real physical systems."

So the press release is a little over-hyped. But this is real progress nonetheless (assuming the results actually hold up).

[UPDATE] It should be noted that this is still a very long way away from cracking RSA. That requires quantum error correction, which this work doesn't address at all. This work is in a completely different regime of quantum computing, looking for practical applications that use a quantum computer to simulate a physical quantum system faster than a classical computer can. The hardware improvements that produced progress in this area might be applicable to QEC some day, this is not direct progress towards implementing Shor's algorithm at all. So your crypto is still safe for the time being.

SO... BTC goes to zero?

no, not really, PQC is already being discussed in pretty much every relevant crypto thing for couple years alearady and there are multiple PQC algos ready to protect important data in banking etc as well

I don’t really understand the threat to banking. Let’s say you crack the encryption key used in my bank between a java payment processing system and a database server. You can’t just inject transactions or something. Is the threat that internal network traffic could be read? Transactions all go to clearing houses anyway. Is it to protect browser->webapp style banking? those all use ec by now anyway, and even if they don’t how do you mitm this traffic?

Where is the exact threat?

> those all use ec by now anyway

As far as i am aware, eliptic curve is also vulnerable to quantum attacks.

The threat is generally both passive eavesdropping to decrypt later and also active MITM attacks. Both of course require the attacker to be in a position to eavesdrop.

> Let’s say you crack the encryption key used in my bank between a java payment processing system and a database server.

Well if you are sitting in the right place on the network then you can.

> how do you mitm this traffic?

Depends on the scenario. If you are government or ISP then its easy. Otherwise it might be difficult. Typical real life scenarios are when the victim is using wifi and the attacker is in the physical vicinity.

Like all things crypto, it always depends on context. What information are you trying to protect and who are you trying to protect.

All that said, people are already experimenting with PQC so it might mostly be moot by the time a quantum computer comes around. On the other hand people are still using md5 so legacy will bite.