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    "headline": "The Single-Copy Quantum Bandit Collapsed to a Classical Strategy",
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    "dek": "Adaptive measurements could not beat spectral measurement plus classical KL-UCB at leading order.",
    "summary": "Adaptive measurements could not beat spectral measurement plus classical KL-UCB at leading order.",
    "body_text": "For finite-dimensional bandits whose arms emit quantum states, the paper proves that measuring each copy in the known reward effect's spectral basis and then running classical KL-UCB is asymptotically instance-optimal within the single-copy policy class. Improvements would require measurements outside that class.",
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      "quantum bandits",
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  "sources": [
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      "source_id": "source-2026-10-01-019",
      "title": "arXiv preprint 2609.40339",
      "publisher": "arXiv",
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      "published_at": "2026-09-30T13:58:22.000-04:00",
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    "title": "The Single-Copy Quantum Bandit Collapsed to a Classical Strategy",
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