Bitcoin Q-Day Recovery Proposal Aims to Let Users Prove Ownership After Quantum Attack
In briefProject Eleven introduced a post-quantum proof designed to verify Bitcoin wallet ownership after Q-Day.The implementation was developed with Binius maintainer Jim Posen and builds on earlier academic research.The prototype is unaudited and would require blockchain protocol support before it could be used. As concerns over Bitcoins quantum security continue to grow, security firm Project Eleven on Thursday unveiled a cryptographic technique designed to address a major concern by allowing users to prove ownership of a wallet after quantum computers become capable of deriving private keys and generating valid digital signatures. In a thread on X on Wednesday, Project Eleven CEO Alex Pruden said the central challenge isnt protecting wallets from quantum attacks—its proving who owns them once those attacks become possible. “How do you prove you still own a wallet after a quantum computer can forge its signatures?” Pruden wrote. “After Q-Day, once a quantum computer can derive an ECC private key from its public key, a valid signature no longer proves ownership. Both the quantum adversary and the legitimate owner are able to produce identical signatures.” “Q-Day” refers to the moment when a quantum computer can break the elliptic curve cryptography that secures Bitcoin transactions. The concern in the industry is that