> Q: Stealing is illegal, so why would anyone use a CRQC to steal Bitcoin?
> A: If you truly believe this, you really should value Bitcoin at 0 – it has many unnecessary components with a lot of overhead, like proof-of-work and digital signatures.
Proof of work is still necessary for two reasons:
1) to fairly distribute all coins (it's not sufficient though, e.g. Bitcoin's halvings still concentrate wealth on early miners/adopters)
2) to provide objective proof for the true transaction history, anchored in energy expenditure.
A related article on Bitcoin Core resistance to upgrading: https://murmurationstwo.substack.com/p/bitcoin-developers-ar...
Why do you need this if you are willing to trust other people not to steal coins or lie?
> 1) to fairly distribute all coins
Same question as above. If you don't care about perfidy, simply use the honor system for coin distribution.
If you do care about perfidy, then you should probably care about people breaking the law to steal your coins.
I've had this thought for awhile actually: how would reproducing some random number be legally "stealing" under any legal system in the world? Putting aside that cryptocurrencies have always been about "code decides" etc, that they're outside of the legal system entirely, but I'm struggling to see where there's any actual property interest here. Randomly generated numbers are not protected by IP in any way. There's no computer fraud act angle or the like here, nobody would be having so much as the slightest interaction with anyone else's private system. They'd merely be taking publicly available unprotected numbers and doing some math on them with their own quantum computer. Somebody else who has something related to those numbers is never deprived of them or interacted with in the slightest. There is nothing resembling "hacking", no flaws in the software exploited, all just math there from the start.
I can understand how suddenly a lot of proponents might wish to cling to and push the idea that it's "illegal" or "stealing", but doesn't appear to be any meat on dem bones. Maybe they hope to generate support to get laws passed banning it, though hard to see that working out either. As a practical matter seems like they're just going to have to agree on a transition to new version using PQE algorithms and try to convert over before it's too late?
Likewise, when government agencies shut down dark net markets (DNMs), they will seize the cryptocurrency funds that the DNM had (from market fees etc., or even funds that belonged to customers and were in escrow etc. by the DNM) if they can (i.e. if they get access to the private keys of DNM owned wallets either by technical means or by convincing the operators of the DNM to hand over the keys). Again because the governments view cryptocurrencies as something more than just random numbers without meaning.
Speaking of seized funds. Let’s say that a government agency had seized a significant amount of bitcoin from a DNM and was transferring those funds to wallets under government agency control. Along comes some guy with a quantum computer and takes those funds for himself. Is the government agency just going to throw its hands in the air and say “oh well, he guessed the random number, nothing more we can do!” No, I think not.
I understand that the bank's ownership of its computer means that hacking into it could be seen as (for example) a trespass. However, what if you somehow persuaded a bank employee to change someone's balance? The bank employee has some kind of authority to do this and the result is once again "just a number".
OK, what if you display some fraudulent information somewhere that leads a bank employee to decide to update a balance?
I don't want to entirely dismiss your intuition because after all there is lots of interest in not relying on legal systems to adjudicate issues related to cryptocurrency transactions. However, changing numbers and causing people or devices to change numbers is not inherently categorically exempt from being considered fraudulent. For that matter, computer fraud laws are often explicitly written to apply to unauthorized alteration of data, not just to unauthorized access to a specific device.
You might try to defend this by saying
* the ownership of cryptocurrency assets is defined as the ability to transfer them, and should not be further or separately interpreted apart from that ability, or
* deceiving a protocol is less obviously wrongful (or at least harder to define) than deceiving a person, or
* computer crime should require undermining someone's intent about the use of devices or data and that intent should be clearly manifested and meaningful, which it arguably isn't in a cryptocurrency system, or
* offline institutions create some kind of intelligible notion of ownership that's related to the non-digital world and this kind of ownership is what laws about theft or fraud aim to protect rather than any other kind of ownership without that non-digital nexus. (although this doesn't seem to be empirically true as ownership of, for example, domain names has been recognized as a form of property by courts since at least Kremen v. Cohen in 2003, even though it is just a matter of a database entry and has no offline existence)
These are interesting conceptual possibilities, but not necessarily persuasive for courts, law enforcement, or cryptocurrency end users.
I suppose we could pass laws to prevent them from ever spending the money in a country that they can control. Even then, they'd have to find ways around the funds being "laundered" through mixers.
The best bet would be to factor satoshi's keys, and then publish them on something like OEIS for some novel-math reason, and let someone else steal them for you.
Of course, inventing and demonstrating a quantum-resistant signature mechanism isn't the same thing as deploying it in consensus or upgrading everyone's UTXOs to it, and it's fair to say that there are many steps in between!
- Tim Ruffing proved that Taproot's commitment scheme was quantum-resilient: https://eprint.iacr.org/2025/1307
- Jonas Nick and Mikhail Kudinov have proposed SHRINCS: https://delvingbitcoin.org/t/shrincs-324-byte-stateful-post-... and SHRIMPS: https://x.com/n1ckler/status/2038695067754328095.
Like publicly destroying ivory /poppy stockpiles while simultaneously holding puts/futures on correlating pharmaceutical financial instruments.
1) Short markets in Bitcoin don't have unlimited depth, and the centralized ones are KYC'd so there's some risk there 2) What if it doesn't tank the price? One thing people have suggested is just burning all the vulnerable coins[1]; it reduces supply so maybe the price will... go up? The point is there's uncertainty.
It’s worth remembering that Ethereum forked for much less (not even a bug in the protocol, but a bug in a private application running on the protocol) and nobody seems too upset about it a decade later.
Existing wallets need to actively commit to some PQ signature mechanism, prior to Q-day.
Yes, this is not ideal! But if the wallet conversion requires active participation, preemptive measures are also not ideal.
That's exactly what it means. (Note also that under ECDSA you can retrieve a public key from a valid signature).
How do you prove anything, after the key material is compromised?
It’s a blockchain, so the simplest would be chain of custody until the chain points undeniably at you. This is not a pure cryptographic device, some social intervention might be needed here.
Now, of course, the irony here would be traditional finance infrastructure winning out over decentralized, which could definitely deal a psychological blow to BTC's perceived value... but it's something I've been thinking about lately as this existential threat rises on the horizon.
EthanHeilman•1h ago
(A) How likely you think it is a CRQC appears by a given time, multiplied by (B) How likely it is you think Bitcoin will not successfully upgrade by that time."
It would interesting to survey people about their answers.
My off the cuff answer is:
2030: A=0.05, B=0.01
2035: A=0.50, B=0.001
2045: A=~1.0, B=~0.0
I reserve the right to change my mind on these answers at any point. This is not a serious prediction.
sayYayToLife•1h ago
EthanHeilman•1h ago
The only thing I am confident in is if it the bigger the fire, the faster the work. I want the Bitcoin community to start the work as early as possible so that it doesn't have to rush because rushing increases the chance of mistakes.
Start early, don't rush.
hackernudes•1h ago
flatline•49m ago