Quantum Computers Are Still Slower Than Calculators, But Bitcoin's Already Building Bunkers

Blockstream CEO Adam Back told attendees at Paris Blockchain Week on Tuesday that Bitcoiners should start building quantum-resistant solutions now, even if the threat remains decades away. "Quantum computing still has a lot to prove. Current systems are essentially lab experiments. I've followed the field for over 25 years, and progress has been incremental," he said. That said, Bitcoin should prepare. Back emphasized the "safest approach" is building optional upgrades that allow migration to quantum-resistant cryptography if needed. Concerns that quantum computers could eventually break blockchain cryptography have fueled industry-wide fear that bad actors could use it to break into crypto wallets, potentially plunging the market into chaos. Back said in November that the quantum threat is still 20 to 40 years away, and explained to Bloomberg earlier this month that today's quantum computers are slower than calculators. Despite this, Blockstream maintains a dedicated quantum team researching potential threat vectors to the Bitcoin network. Part of that work has involved implementing hash-based signatures on Blockstream's Bitcoin layer-2 Liquid Network. "Preparation is key. Making changes in a controlled way is far safer than reacting in a crisis," Back added. He noted the Taproot protocol could also support alternative signature schemes on the Bitcoin network without affecting current users. Last month, Google and California Institute of Technology researchers said functional quantum computers could come sooner than expected and that far less computing power is needed to break cryptography than previously thought. Google went as far as to say quantum computers could potentially break Bitcoin's cryptography in as quickly as nine minutes, allowing hackers to perform an "on-spend" attack. When asked what would happen if the quantum threat arrives sooner than anticipated, Back said Bitcoin developers would "act quickly." "We've seen that before — bugs have been identified and fixed within hours. When something becomes urgent, it focuses attention and drives consensus." On Tuesday, Bitcoin developer Jameson Lopp and five other crypto security researchers introduced a proposal to freeze quantum-vulnerable Bitcoin — including Satoshi Nakamoto's $81.9 billion stash — to prevent it from being stolen once quantum computers become functional. The proposal drew sharp criticism from several members of the Bitcoin community, including developer and researcher Mark Erhardt, who described it as "authoritarian and confiscatory." Phil Geiger, head of business development at Metaplanet, said: "We have to steal people's money to prevent their money from being stolen."