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    "headline": "Hardware Noise, Not Expressibility, Stopped the Quantum Simulation",
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    "dek": "At four lattice sites, 1% depolarizing noise drove mean error as high as 52.81%.",
    "summary": "At four lattice sites, 1% depolarizing noise drove mean error as high as 52.81%.",
    "body_text": "A two-flavor Schwinger-model study scales variational circuits from two to six staggered lattice sites and separates expressibility, trainability and hardware noise. Its noiseless four-site control reached 0.12% mean error, while the same circuit under 1% depolarizing noise reached 25.69% to 52.81%. The result is a model-specific diagnosis, not a bound for all quantum simulations.",
    "why_it_matters": "At four lattice sites, 1% depolarizing noise drove mean error as high as 52.81%.",
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      "The result is a model-specific diagnosis, not a bound for all quantum simulations."
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    "tags": [
      "quantum simulation",
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      "variational circuits"
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      "source_id": "source-2026-09-28-018",
      "title": "arXiv preprint 2609.30496",
      "publisher": "arXiv",
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