IBM cuts quantum error rates 10x as computer completes hard task in 15 minutes IBM researchers completed a difficult quantum computation in 15 minutes while cutting effective logical error rates to 10x below physical rates. Read Next: US neighbor's hydrogen reactor tech could enter German-led submarine productionIBM and University of Chicago researchers have demonstrated a quantum computing system that they say can perform a computationally difficult task while also providing evidence that the result is accurate. The experiment used error-corrected logical qubits to run a complex quantum circuit that classical simulation methods could not practically reproduce. IBM’s quantum computer completed the computation in about 15 minutes, while leading classical approaches faced prohibitive runtimes. More importantly, the researchers found that the effective logical error rate was 10 times lower than the physical error rate. That means the error-correction system substantially reduced the impact of hardware-level errors during the computation. The result addresses a major problem in demonstrating quantum advantage. As quantum computations become too difficult for classical computers to reproduce, independently checking whether the quantum machine produced the correct result also becomes harder. Quantum results need proof Researchers have traditionally used a technique called random circuit sampling to test whether quantum computers can perform calculations beyond the practical reach of classical machines. The method generates complex patterns that are difficult for classical systems to reproduce. But there is a catch. If the calculation is too difficult for a classical computer to simulate, it can also become difficult to verify the quantum computer’s output. More from Science See AllThe IBM and University of Chicago team used a different circuit design that maintains the computational difficulty of random circuit sampling while allowing errors to be detected during the calculation. “Verification remains one of the biggest challenges in firmly establishing experimental quantum advantage,” said