A panel at ETH Denver highlighted growing concerns about how quantum computing could threaten Bitcoin’s cryptography. Experts explained that Bitcoin’s SHA-256 hashing is likely safe for now, as breaking it would require an unrealistically large quantum computer using Grover’s algorithm. The more immediate risk lies in digital signatures, which could be broken by Shor’s algorithm if sufficiently powerful quantum machines emerge, potentially allowing attackers to derive private keys from public keys and steal funds.

Security researchers noted that while current quantum hardware is not yet capable of this, rapid advances by major tech firms suggest progress is accelerating. Parts of the crypto industry are already preparing: the Ethereum Foundation has formed a post-quantum security team, and Coinbase has launched advisory efforts on quantum risk.

Estimates of the quantum resources needed to break Bitcoin signatures have dropped sharply, and millions of coins are already in addresses with exposed public keys, making them more vulnerable in a future quantum attack. Speakers stressed that beyond technical fixes, achieving community consensus on how to migrate or protect old coins — including possibly untouched early holdings — could be politically and operationally difficult, yet critical to avoiding a severe network shock.