Grayscale, a digital asset management firm, has emphasized the need for expedited efforts to make public blockchains resistant to quantum computing threats in a recent research note. The note underscores that while the technical solutions to achieve quantum resistance are already available, the main obstacle lies in gaining consensus among decentralized communities to implement these solutions. This comes on the heels of a recent paper by Google Quantum AI, which suggests that breaking 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 research note highlights four key takeaways from Google's findings that Grayscale finds compelling.
Firstly, progress toward developing a quantum computer capable of breaking current cryptographic standards may occur in sudden, unpredictable leaps rather than gradual advancements. Secondly, post-quantum cryptography, which can secure internet traffic and certain blockchain transactions, is already mature and available. Thirdly, the quantum risk varies significantly across different blockchains, depending on factors such as their transaction models, consensus mechanisms, and block times. Lastly, from a purely engineering perspective, Bitcoin's use of a UTXO model, proof-of-work consensus, lack of native smart contracts, and specific address types reduces its quantum risk compared to other chains.
However, the more challenging question revolves around the approximately 6.9 million Bitcoins held in wallets with publicly exposed keys on the blockchain, including an estimated 1 million believed to belong to Bitcoin's creator, Satoshi Nakamoto. Various options have been proposed, including burning these coins, taking no action, or limiting their release rate to mitigate potential risks. The Bitcoin community's history of contentious debates over protocol changes, such as the dispute over image data stored in blocks last year, complicates the decision-making process.
In contrast, Ethereum faces different challenges, with Google's paper identifying multiple attack vectors worth over $100 billion in combined exposure. An Ethereum Foundation researcher estimated a 10% chance of quantum key recovery by 2032, highlighting the need for timely migration strategies.