Grayscale, a digital asset manager, has released a research note emphasizing the need for accelerated efforts to make public blockchains resistant to quantum computing. Although the technical pathways to achieve this are clear, the main obstacle lies in garnering consensus among decentralized communities to implement these solutions. This comes on the heels of 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, a significantly lower threshold than previously estimated, and could be executed in under nine minutes.
The research note highlights four key takeaways from Google's findings, including the potential for rapid progress in quantum computing, the maturity of post-quantum cryptography, varying quantum risks across different blockchains, and the unpredictability of timelines. From a purely technical standpoint, Bitcoin is argued to have a lower quantum risk due to its UTXO model, proof-of-work consensus, lack of native smart contracts, and certain address types. However, the question of what to do with the approximately 6.9 million BTC in wallets with permanently exposed public keys on the blockchain, including those believed to belong to Satoshi Nakamoto, poses a significant governance challenge. Options such as burning these coins, taking no action, or limiting their release rate are proposed, but the history of contentious debates within the Bitcoin community over protocol changes may hinder progress.
In contrast, Ethereum faces different challenges, with identified attack vectors worth over $100 billion and a notable effort by the Ethereum Foundation to stake ether into validators, although a public address on quantum migration timelines has not been provided.