ARK Invest’s Lorenzo Valente is more optimistic Bitcoin will beat Q Day

Quantum computing has long been the boogeyman of Bitcoin security debates. One of ARK Invest’s top crypto researchers now sounds less worried about it. Lorenzo Valente, ARK’s Director of Research for Digital Assets, says he is more optimistic than he was a year ago that Bitcoin will deploy a quantum fix before “Q Day.” That is the hypothetical moment when a quantum machine becomes strong enough to crack the cryptography protecting Bitcoin addresses. What Valente is actually saying Valente’s comments, made in mid-October 2026, mark a change from his view in mid-2025. His outlook tracks a white paper ARK co-authored with Unchained, published on March 12, 2026. That paper lays out five stages of quantum risk to Bitcoin. The core argument is that the threat builds gradually rather than arriving overnight. The white paper treats quantum risk as a long-term issue. It does not frame Q Day as a sudden existential event that wipes out Bitcoin in an afternoon. That gradual timeline is what gives developers room to ship protocol upgrades. Those include post-quantum signature schemes, which are cryptographic methods designed to hold up even against quantum attackers. The numbers behind the wor...