Google’s Willow Chip Advances Quantum Threat to Satoshi-Era Bitcoin

quantum threat — Google’s new Willow quantum chip has made a significant advance in error correction, potentially accelerating the timeline for a future quantum computing threat to older Bitcoin wallets.

The chip reportedly reduces errors by about 40 times when preparing “magic states,” a critical resource needed for the complex calculations a quantum computer would use to crack cryptographic keys. The experiment achieved a state preparation fidelity of about 99.99% for successful attempts, though only about 8% of preparation tries succeeded overall.

While this breakthrough does not make an attack on Bitcoin 40 times cheaper or immediately feasible, it represents a meaningful step in overcoming a major hardware bottleneck. Researchers estimate that breaking a Bitcoin wallet’s Elliptic Curve Digital Signature Algorithm (ECDSA) would require a quantum computer to sustain roughly 500,000 reliable magic states per second.

The development is seen as a particular concern for so-called “Satoshi-era” Bitcoin held in wallets that have never moved coins and use the original, non-quantum-resistant ECDSA. The findings, published on October 16, highlight the ongoing race between quantum computing advances and the cryptocurrency industry’s need to transition to post-quantum cryptography.