Adam Back Disputes Google's Quantum Threat Paper: 'No Vulnerability'

Bitcoin's Chief Cryptographer Adam Back has pushed back against Google's recent quantum threat paper. According to Back, the paper misidentified a vulnerability in Bitcoin that does not exist. He pointed out that Bitcoin's Taproot upgrade, activated in 2021 but designed between 2018 and 2019, included a mechanism called a 'tapleaf' specifically to allow future compatibility with post-quantum cryptography.

Back explained that the Google paper 'confuses Taproot/Schnorr,' saying that the protocol has already built-in pathways to switch to quantum-safe alternatives without losing access to funds. He cited an academic proof by Tim Ruffing, which mathematically demonstrated that Taproot's commitment scheme is post-quantum secure.

Back also warned that rushing new cryptography into Bitcoin would be more dangerous than the quantum threat itself, pointing to the history of post-quantum cryptography competitions where most candidates were broken or rejected before standards were finalized. This comes as Bitcoin was trading near $67,000, with a 0.4% increase over the past 24 hours.