Grayscale, a digital asset management firm, has released a research note advocating for expedited efforts to enhance public blockchains' resistance to quantum computing. The note posits that the technical solutions for this issue already exist but the more daunting task is securing agreement among decentralized communities to implement these solutions.
This follows a week of significant industry response to a paper by Google Quantum AI, which discovered that compromising bitcoin's elliptic curve cryptography would require fewer qubits than previously estimated and could be executed rapidly. The study by Google Quantum AI found that breaking bitcoin's cryptography could be achieved with less than 500,000 physical qubits and in under nine minutes, once the necessary machinery is prepared. According to CoinDesk's analysis, such an attack would give an attacker approximately a 41% chance of stealing funds before a transaction is confirmed on the bitcoin network.
The note highlights four key points from the Google research that Grayscale found compelling: progress toward a quantum computer capable of cryptographic relevance may occur in sudden advancements rather than steadily; post-quantum cryptography is already mature and in use for securing internet traffic and certain blockchain transactions; the risk posed by quantum computing varies significantly between blockchains based on factors like transaction model, consensus mechanism, and block time; and from a purely technical standpoint, bitcoin has a lower quantum risk due to its UTXO model, proof-of-work consensus, lack of native smart contracts, and specific address types that are not vulnerable to quantum attacks if not reused. However, a more challenging question arises regarding the roughly 6.9 million BTC in wallets with publicly exposed keys on the blockchain, including an estimated 1 million believed to belong to bitcoin's creator, Satoshi Nakamoto. Binance co-founder Changpeng Zhao recently raised this question, suggesting that if Satoshi's coins are moved during a migration, it would indicate his involvement, and if they remain unmoved, it might be preferable to lock or effectively burn those addresses. Grayscale outlines similar options - burning the coins, taking no action, or intentionally slowing their release by limiting the spending rate from vulnerable addresses - but notes that the bitcoin community has a history of contentious debates over protocol changes, citing last year's dispute over image data storage in blocks.
In contrast, Ethereum faces different challenges, with Google's paper identifying multiple attack vectors worth over $100 billion and an Ethereum Foundation researcher estimating a 10% chance of quantum key recovery by 2032, prompting the foundation to stake significant amounts of ether into validators.