In a newly released research note, digital asset management firm Grayscale expressed support for expedited efforts to enhance public blockchains' resistance to quantum computing. The note emphasizes that although technical solutions to achieve quantum safety already exist, the more daunting task lies in securing agreement among decentralized communities to implement these solutions. This comes on the heels of a recent paper by Google Quantum AI, which revealed that compromising bitcoin's elliptic curve cryptography could be achieved with fewer than 500,000 physical qubits, significantly lowering the estimated threshold.
The analysis by CoinDesk indicates that such an attack could grant an attacker a roughly 41% chance of stealing funds prior to a bitcoin transaction's confirmation. Grayscale's research highlights four key takeaways from Google's findings, including the potential for sudden advancements in quantum computing capabilities and the maturity of post-quantum cryptography, which is already securing certain internet and blockchain transactions. The firm also notes that quantum risk varies substantially across different blockchains, influenced by factors such as transaction models, consensus mechanisms, and block times.
From a purely technical standpoint, Grayscale argues that bitcoin's use of a UTXO model, proof-of-work consensus, lack of native smart contracts, and specific address types contributes to its lower quantum risk compared to other chains. However, the more complex issue revolves around the approximately 6.9 million BTC held in wallets with publicly exposed keys on the blockchain, including an estimated 1 million coins believed to belong to bitcoin's creator, Satoshi Nakamoto.
This has sparked debate on how to proceed, with options including burning these coins, taking no action, or imposing a controlled release. The discussion echoes sentiments expressed by Binance co-founder Changpeng Zhao, who suggested that any movement of Satoshi's coins during a potential migration could indicate his continued involvement, while a lack of movement might justify locking or effectively burning those addresses. Grayscale frames these options similarly but cautions that the bitcoin community's history of contentious debates over protocol changes may hinder consensus. In contrast, Ethereum faces distinct challenges, with Google's paper identifying multiple vulnerabilities worth over $100 billion.
An Ethereum Foundation researcher estimates a 10% chance of quantum key recovery by 2032, underscoring the need for proactive measures to ensure the network's security in the face of quantum computing threats.