Quantum error correction advances show 40x error reduction and 99.99% logical fidelity

Google Quantum AI says it demonstrated magic state cultivation on Willow, cutting errors 40x versus previous methods and reaching 99.99% logical fidelity. A user also reports a successful transfer between quantum error-correcting codes. Another user, citing Nvidia, says a 104-qubit simulation on Europe's JUPITER supercomputer validated the method, which needs 90% fewer qubits than earlier methods.