Random circuit sampling experiments have demonstrated quantum advantage by solving finite-fidelity computational tasks at around 0.1% fidelity, which remains exponentially harder for classical computers than trivial baselines. The key insight is a phase transition in the weak-noise regime where cross-entropy benchmarking (XEB) reliably proxies fidelity, validated through extensive noise characterization and theoretical modeling. While not device-independent, the evidence parallels other major physics discoveries like the Higgs boson, combining experimental data with theoretical frameworks to establish that quantum computers solved a classically intractable problem.
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What’s the issue?The noisy sampling taskQuantum advantage of finite-fidelity RCSGetting the scaling right: weak noise and low depthFidelity versus XEB: a phase transitionWhere are the experiments?The phase transition matters!But we can’t compute the XEB!That’s exactly how experiments work!What are the counter-arguments?Sort: