In a recent research note, Grayscale emphasized the need to accelerate efforts to make public blockchains resistant to quantum attacks, citing existing technical solutions but highlighting the difficulty in achieving consensus among decentralized communities to implement these solutions. The note comes in response to a recent paper by Google Quantum AI, which found that breaking bitcoin's elliptic curve cryptography could be achieved with fewer than 500,000 physical qubits, significantly lowering the estimated threshold.
This discovery sparked intense industry discussion, with CoinDesk's analysis indicating that such an attack would give hackers a roughly 41% chance of stealing funds before a bitcoin transaction is confirmed. Grayscale's note outlined four key takeaways from the Google research, including the potential for sudden progress in quantum computing, the maturity of post-quantum cryptography, varying quantum risk across different blockchains, and the relatively lower quantum risk of bitcoin due to its UTXO model and proof-of-work consensus. However, the note also raised the complex issue of addressing the approximately 6.9 million BTC in wallets with exposed public keys, including an estimated 1 million coins believed to belong to Satoshi Nakamoto. Possible solutions include burning these coins, taking no action, or limiting their release rate, but Grayscale noted that such decisions are contentious and require community consensus, pointing to past debates as an example.
In contrast, Ethereum faces distinct challenges, with five identified attack vectors worth over $100 billion and an estimated 10% chance of quantum key recovery by 2032, prompting the Ethereum Foundation to stake substantial amounts of ether into validators.