Adam Back Dismisses Warnings That Quantum Computing Poses Existential Threat to Bitcoin

Blockstream co-founder Adam Back has rejected claims that quantum computing threatens Bitcoin with collapse or lost market dominance, calling such warnings alarmist. His pushback followed warnings that Bitcoin risks losing its leading market capitalization without an urgent quantum-resistant upgrade to protect public-key cryptography. Back noted that while Shor's algorithm could challenge ECDSA and Schnorr signatures, hash functions like SHA-256 remain resilient. Furthermore, post-quantum defenses are already in development, with developers actively testing the hash-based SHRINCS signature scheme and draft BIPs on sidechains using batch verification and STARK proofs to limit blockchain bloat.