Building a utility-scale quantum computer that can crack one of the most vital cryptosystems—elliptic curves—doesn’t require nearly the resources anticipated just a year or two ago, two independently written whitepapers have concluded.

New research from Google's Quantum AI team sharply lowers the estimated resources needed for a quantum computer to break bitcoin and Ethereum wallet cryptography, suggesting such machines could arrive...

Google researchers warned that future quantum computers may be able to break some of the cryptography protecting Bitcoin and other digital assets with fewer resources than previously thought, adding urgency to the debate over how the industry should prepare.