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    "headline": "The Hydrogen Forest Sharpens the Cosmic Ruler",
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    "dek": "A reconstruction method cut radial BAO damping in half and improved distance-parameter precision in DESI-like simulations.",
    "summary": "A reconstruction method cut radial BAO damping in half and improved distance-parameter precision in DESI-like simulations.",
    "body_text": "The Lyman-alpha forest traces matter at high redshift, but nonlinear structure blurs the baryon-acoustic-oscillation scale used as a cosmic ruler. The authors adapt Zel'dovich reconstruction from galaxy surveys to simulated forest data. In fully sampled boxes it halved radial damping and reduced radial and transverse parameter uncertainties by roughly 25 and 15 percent. With a DESI-like mask, either the forest itself or an external tracer recovered comparable gains, improving the reported figure of merit by about 1.65. These are simulation validations; application to observational data remains the next test.",
    "why_it_matters": "A reconstruction method cut radial BAO damping in half and improved distance-parameter precision in DESI-like simulations.",
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    "first_published_at": "2026-10-29T09:00:00.000-04:00",
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    "tags": [
      "cosmology",
      "DESI",
      "baryon acoustic oscillations",
      "simulation"
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      "source_id": "source-2026-10-29-015",
      "title": "arXiv preprint 2610.37664, original v1",
      "publisher": "arXiv",
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    "title": "The Hydrogen Forest Sharpens the Cosmic Ruler",
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