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    "story_id": "mp-2026-09-16-015",
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    "headline": "Continuous-Variable QKD Closed Its Coherent-Attack Gap",
    "slug": "continuous-variable-qkd-closed-its-coherent-attack-gap",
    "dek": "A composable finite-size proof retained positive modeled key rates beyond 70 kilometers with imperfect detectors.",
    "summary": "A composable finite-size proof retained positive modeled key rates beyond 70 kilometers with imperfect detectors.",
    "body_text": "Discrete-modulated continuous-variable quantum key distribution has used experimentally attractive telecom components without a complete finite-size proof against coherent attacks. This work introduces an infinite-dimensional entropy accumulation theorem and a dimension-reduction method, covering imperfect detectors and fixed- or variable-length protocols. The computed bounds recover known asymptotic rates and remain positive beyond 70 kilometers for the reported block sizes and parameters. It is a security proof and numerical result, not a field deployment.",
    "why_it_matters": "A composable finite-size proof retained positive modeled key rates beyond 70 kilometers with imperfect detectors.",
    "limitations": [
      "The computed bounds recover known asymptotic rates and remain positive beyond 70 kilometers for the reported block sizes and parameters.",
      "It is a security proof and numerical result, not a field deployment."
    ],
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    "first_published_at": "2026-09-16T09:00:00.000-04:00",
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        "qualification": "The computed bounds recover known asymptotic rates and remain positive beyond 70 kilometers for the reported block sizes and parameters."
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    "tags": [
      "quantum cryptography",
      "security proof",
      "continuous variables"
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  "sources": [
    {
      "source_id": "source-2026-09-16-017",
      "title": "arXiv preprint 2609.16105",
      "publisher": "arXiv",
      "url": "https://arxiv.org/abs/2609.16105",
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      "published_at": "2026-09-14T20:00:00.000-04:00",
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    "name": "The Machine Press",
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  "cite_this_report": {
    "title": "Continuous-Variable QKD Closed Its Coherent-Attack Gap",
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