Google Scientist Slams Bitcoin Quantum Test Over Flawed Benchmark

A recent contest aimed at testing the quantum resistance of Bitcoin has been called into question by a Google researcher. Craig Gidney, a research scientist on Google's quantum team, wrote in an April 25 blog post that Project Eleven's Q-Day Prize was flawed in its approach.

The prize, which was awarded to Giancarlo Lelli for deriving a 15-bit elliptic curve private key on cloud-accessible hardware, was claimed to be a significant achievement. However, Gidney argued that the benchmark used in the contest is not meaningful and that current quantum computers cannot measure it.

Gidney pointed out that Shor's algorithm requires quantum error correction for cryptographically meaningful instances, but current machines hit roughly one error per thousand gates against billions required. He also noted that GitHub user Yuval Adam had reportedly swapped the quantum calls with random calls and got results indistinguishable from the original.

Project Eleven CEO Alex Pruden defended the contest's aim, stating that resource requirements for such attacks keep dropping. However, Gidney's critique has raised questions about the validity of the Q-Day Prize and its implications for Bitcoin's security.