Divided Opinions Emerge in Bitcoin's Quantum Computing Discussion as Adam Back Advocates for Optional Upgrades

The debate surrounding the threat of quantum computing to Bitcoin has sparked intense discussion among the cryptocurrency's prominent developers, with vastly differing opinions on the best course of action. Blockstream CEO Adam Back addressed attendees at Paris Blockchain Week, suggesting that Bitcoin should prioritize building optional quantum-resistant upgrades. This approach, according to Back, allows for a more controlled and safer transition. He highlighted his company's experiments with quantum-resistant transaction signatures on the Liquid network, a sister network of Bitcoin, and noted that the 2021 Taproot upgrade provides the flexibility to incorporate new signature methods without disrupting current users. Back's comments come on the heels of a proposal by Jameson Lopp, which recommends phasing out quantum-vulnerable addresses over a five-year period and freezing any non-compliant coins. This proposal has sparked concerns, as it could affect approximately 1 million bitcoins linked to Bitcoin's creator, Satoshi Nakamoto, and an estimated 5.6 million inactive coins. Back's stance serves as an implicit alternative to Lopp's proposal, emphasizing the ability of Bitcoin's developer community to respond swiftly to emerging threats. The core of the disagreement lies in the differing beliefs about the community's capacity to coordinate a rapid response to a sudden quantum breakthrough, with Back betting on the community's ability to adapt quickly and Lopp advocating for a pre-scheduled freeze to avoid a chaotic migration.