Google Paper Slashes Qubit Barrier for Cracking Bitcoin, Accelerates 2029 PQC Deadline

Technological shockwaves to cryptography often follow hardware leaps: the Allies’ 1943 Colossus abruptly obsoleted German Enigma ciphers, and the 1997–98 DES Challenge cracked 56-bit keys once deemed secure. Google’s downsizing of the qubit requirement repeats this pattern, showing that defensive key lengths age faster than doctrine predicts. The episode sits at the intersection of three megatrends—Moore-law-like scaling of qubit counts, the race to commercialize quantum hardware and software (see Horizon Quantum’s IPO the same day), and the dependence of trillions of dollars in digital assets on math problems that may not survive the decade. Whether blockchains can coordinate a hard-fork migration mirrors the Y2K remediation of the late 1990s; success will normalize quantum-safe standards, failure could reset trust in decentralized finance. On a 100-year timeline, the event is a mile-marker in the perpetual tug-of-war between code-makers and code-breakers, hinting that future money and state secrets will rely on physics (quantum-resistant lattices, photonic networks) rather than arithmetic complexity alone.