Time is Running Out for Bitcoin to Mitigate Quantum Threat, Putting 6.9 Million BTC at Risk

While not all aspects of bitcoin are vulnerable to quantum computers, ownership is at significant risk. Bitcoin wallets rely on a specific type of mathematics that can be broken by quantum computers, potentially allowing hackers to drain approximately 6.9 million BTC, including those held by the cryptocurrency's pseudonymous creator, Satoshi Nakamoto. The exposed pool of bitcoin includes early coins and any wallet that has been spent from, as spending reveals the key for the remaining balance. A quantum attacker could work through these wallets at their own pace, without needing to rush against ongoing transactions. The 2021 Taproot upgrade inadvertently expanded the problem by publishing the key protecting remaining bitcoin at an address after a transaction. To address this, Ethereum has had a formal quantum-resistant program in place since 2018, with four full-time teams working on the migration and a dedicated website to track progress. In contrast, Bitcoin lacks a concrete strategy, although there are proposals like BIP-360 and a detection system from BitMEX Research. However, these proposals lack broad support from core developers and only solve part of the problem. The lack of a central authority and a governance process makes it challenging for Bitcoin to implement effective solutions, requiring decisions that the network has historically avoided. The coordination problem is further complicated by the need to make decisions about old address formats, exposed coins, and the potential consequences for coins whose owners cannot or will not migrate. As the timeline for a potential quantum attack shortens, the question remains whether Bitcoin can coordinate the necessary security upgrade before it's too late.