{
  "abstract": "Naive estimates based on Einstein gravity with Lagrangian $\\frac{1}{2}M_{pl}^{2}(R-2Λ)$ suggest that, if the radiation era extended back to the Big Bang (i.e., as far back as the classical spacetime background makes sense), this would result in an over-production of dark matter and a relic cosmic background of thermal gravitons. Here we revisit these conclusions in quadratic gravity, the minimal renormalizable completion of Einstein gravity, whose Lagrangian also includes the terms $\\frac{1}{6}f_0^{-2}R^2-\\frac{1}{2}f_{2}^{-2}C^{2}$. Assuming the radiation era does extend back to the bang, we find a novel relation between the coefficient $f_{2}$ and the dark matter mass $m_{dm}$, needed to obtain the correct dark matter abundance. This yields a new gravitational production mechanism for dark matter (e.g., stable right-handed neutrinos). Moreover, the presence or absence of the relic graviton background (detectable by forthcoming CMB experiments via its small imprint on $N_{\\rm eff}$) will place new constraints on $f_{0}, f_{2}$.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.11750",
  "author_total": 3,
  "authors": [
    {
      "name": "Latham Boyle"
    },
    {
      "name": "Neil Turok"
    },
    {
      "name": "Vatsalya Vaibhav"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/envt28wanwjk7.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.11750",
  "fulltext_url": null,
  "id": "envt28wanwjk7",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.11750",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.CO"
    ],
    [
      "arxiv",
      "gr-qc"
    ],
    [
      "arxiv",
      "hep-ph"
    ],
    [
      "arxiv",
      "hep-th"
    ],
    [
      "openalex",
      "3103|Cosmology and Gravitation Theories"
    ]
  ],
  "openalex": "W7212269639",
  "pdf_url": "https://arxiv.org/pdf/2609.11750",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-10",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/envt28wanwjk7.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:26Z",
      "native_id": "2609.11750",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.11750"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-ph",
      "subfield": "high-energy"
    }
  ],
  "title": "Might the radiation era extend back to the Big Bang? On dark matter production and the relic graviton background in quadratic gravity",
  "title_text": "Might the radiation era extend back to the Big Bang? On dark matter production and the relic graviton background in quadratic gravity",
  "type": "preprint",
  "updated_at": "2026-10-30T12:20:26Z",
  "url": "https://research.draconitic.com/paper/envt28wanwjk7",
  "venue": "arXiv",
  "versions": []
}