In a recent research note, Grayscale, a digital asset management company, has advocated for expedited efforts to enhance public blockchains' resistance to quantum computing. The note emphasizes that although technical solutions to this issue already exist, the more daunting task lies in convincing decentralized communities to adopt these solutions. This follows a week of intense industry discussion sparked by a paper from Google Quantum AI, which revealed that compromising bitcoin's elliptic curve cryptography could be achieved with fewer than 500,000 physical qubits, a significant reduction from previous estimates, and could be executed in approximately nine minutes. The paper's findings suggest that an attacker could have a roughly 41% chance of stealing funds before a bitcoin transaction is confirmed.
Grayscale's research highlights four key takeaways from Google's study, including the potential for sudden advancements in quantum computing capabilities, the maturity of post-quantum cryptography in securing internet traffic and certain blockchain transactions, and the variability of quantum risk across different blockchains. 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 specific address types.
However, the more complex issue revolves around the approximately 6.9 million BTC in wallets with publicly exposed keys on the blockchain, including an estimated 1 million coins believed to belong to Satoshi Nakamoto. The question of how to handle these vulnerable coins, whether by burning them, taking no action, or limiting their release, poses significant governance challenges, especially given the bitcoin community's history of contentious debates over protocol changes. This contrasts with Ethereum, which faces multiple attack vectors worth over $100 billion and has seen aggressive staking by the Ethereum Foundation, though it has not publicly disclosed its quantum migration timelines.