{
  "abstract": "Spectral-siren cosmology constrains the Hubble constant $H_0$ using gravitational-wave observations of compact-binary coalescences. The method combines luminosity distances inferred from the waveform with redshift information statistically encoded in population features of the source-frame mass spectrum. Because the detector measures redshifted masses, structure in the intrinsic mass distribution acts as an internal ``ruler,'' making the inference sensitive to assumptions about the population model. In particular, redshift evolution of the mass spectrum is widely discussed as a potential systematic for $H_0$ measurements. We revisit spectral-siren constraints with the GWTC-4.0 binary black hole catalog, explicitly allowing the main mass scales of a standard parametric mass model to evolve with redshift. We find no compelling evidence for evolution at current sensitivity. Allowing evolution produces a modest, nonstatistically significant shift of the $H_0$ posterior toward lower values, which we interpret with targeted posterior and event-level diagnostics. Importantly, the associated systematic uncertainty is subdominant to that induced by alternative redshift-independent descriptions of the mass spectrum, such as the number of spectral features and the functional form used to model them. Our results indicate that, at current sensitivity, spectral-siren constraints on $H_0$ are robust to redshift evolution of the mass spectrum within the flexibility explored here. Using injection studies, we show that this mild $H_0$ shift is reproduced when a nonevolving underlying population is analyzed with an evolving model, consistent with an overflexible population description at the present signal-to-noise. The sign and magnitude of the shift can, however, depend on detector sensitivity and redshift reach as the population features become increasingly constrained directly by the data.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: Phys.Rev.D 114 (2026) 6, 063503",
  "arxiv": "2605.20112",
  "author_total": 3,
  "authors": [
    {
      "name": "Alessandro Agapito"
    },
    {
      "name": "Viola De Renzis"
    },
    {
      "name": "Michele Mancarella"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b7k3n4x4zqc90.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2605.20112",
  "fulltext_url": null,
  "id": "b7k3n4x4zqc90",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2605.20112",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.CO"
    ],
    [
      "arxiv",
      "astro-ph.HE"
    ],
    [
      "arxiv",
      "gr-qc"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2605.20112",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-18",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/b7k3n4x4zqc90.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:03Z",
      "native_id": "2605.20112",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2605.20112"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    },
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    }
  ],
  "title": "Gravitational-wave constraints on $H_0$ are robust to putative redshift evolution in the binary black hole mass spectrum at current sensitivity",
  "title_text": "Gravitational-wave constraints on H_0 are robust to putative redshift evolution in the binary black hole mass spectrum at current sensitivity",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:03Z",
  "url": "https://research.draconitic.com/paper/b7k3n4x4zqc90",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1103/jk7y-ddyb",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}