Researchers have demonstrated a quantum computation that appears to exceed the practical capabilities of leading classical simulation methods while also addressing a longstanding problem: how to verify the result. A quantum computer completed a difficult calculation in about 15 minutes, while leading classical simulation methods would require prohibitive amounts of time. Just as importantly, the experiment included a way to establish confidence that the quantum result was accurate. IBM and University of Chicago researchers announced the demonstration on July 30, 2026, presenting it as evidence that quantum computing has met the central requirements for quantum advantage. This means completing a task beyond the practical reach of leading classical methods while providing a reliable measure of how faithfully the quantum computation was performed. In a paper published on arXiv, the researchers describe a new design for encoded quantum circuits that allowed them to pursue both goals at once. The experiment became one of the largest demonstrations of logical quantum computing reported so far. The circuits and results have also been released publicly through the Quantum Advantage Tracker. Verification has remained the central barrier Random circuit sampling (RCS) has long served as a benchmark for testing whether quantum computers can outperform classical systems. In this task, a quantum computer produces patterns so complicated that classical computers cannot efficiently recreate them. The harder the calculation becomes, however, the more difficult it is to confirm that the quantum computer produced the correct output. Eventually, verification itself can become infeasible unless researchers make substantial assumptions about how the machine operates internally. The IBM and University of Chicago experiment addressed this problem with a more structured alternative to RCS. The researchers proved that the new approach preserves the same standards of computational hardness while allowing errors to be detected as the calculation proceeds. “Verification remains one