Google Warns Quantum Computers Could Break Bitcoin and Ethereum in Minutes

Google's Quantum AI team has published research suggesting that breaking Bitcoin (BTC) and Ethereum (ETH) cryptography could be done with significantly fewer resources than previously estimated.

The study estimates that a superconducting quantum processor could crack the 256-bit elliptic curve cryptography used in most blockchain wallets and transactions in minutes, assuming hardware capabilities consistent with some of Google's existing flagship processors.

This would give an attacker a 41% chance of beating Bitcoin's 10-minute block confirmation window if they were to calculate a private key from a briefly exposed public key. Ethereum may face slightly less exposure on this front due to its faster transaction confirmation times.

The findings have raised concerns about the security of blockchain transactions, particularly those related to Bitcoin's 2021 Taproot upgrade. This upgrade improved privacy and efficiency but began exposing public keys on-chain by default, widening the pool of quantum-vulnerable coins to an estimated 6.9 million BTC - roughly one-third of Bitcoin's total supply.

Nic Carter, co-founder of Coin Metrics and a Bitcoin advocate, has highlighted the urgency of this situation, pointing out that even once the necessary hardware arrives, the actual migration process will take years.