{
  "abstract": "We use 50 Sobol-sampled VariableTNG simulations, varying eight subgrid parameters at fixed cosmology and initial conditions, to determine which baryonic processes regulate galaxies and black holes at $z=6$ and $z=8$. We compare the simulations with recent high-redshift measurements of the stellar mass function, star-forming main sequence, stellar and gas-phase mass-metallicity relations, stellar mass-size relation, and black-hole host and accretion properties. The simulations reproduce several broad trends in these observables, although differences remain in gas-phase metallicity, galaxy size, and the most extreme black-hole populations. Given the substantial uncertainties in both the physical modelling and the observational inference of high-redshift galaxy properties, we regard these differences as diagnostic tensions rather than definitive model failures. Random-forest analyses reveal a clear hierarchy in parameter sensitivity. The abundance of low-mass galaxies is regulated primarily by stellar feedback, particularly the supernova temperature $T_{\\mathrm{SN}}$ and thermal wind fraction $τ_{\\mathrm{w}}$, whereas the sensitivity of the scatter in the star-forming main sequence is weaker and redshift dependent. The high-accretion tail of black-hole growth depends on black-hole seeding and feedback parameters, but also on $T_{\\mathrm{SN}}$, suggesting that stellar feedback indirectly regulates rapid black-hole growth through its impact on the available gas supply. Although cosmic variance can obscure these intrinsic responses in independent small volumes, our controlled experiment identifies stellar feedback as a common physical link between early low-mass galaxy formation and rapid black-hole growth.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.17272",
  "author_total": 6,
  "authors": [
    {
      "name": "Kexin Liu"
    },
    {
      "name": "Hong Guo"
    },
    {
      "name": "Luis C. Ho"
    },
    {
      "name": "Tao Wang"
    },
    {
      "name": "Yikai Liu"
    },
    {
      "name": "Volker Springel"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/eqc16gj0be0ph.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.17272",
  "fulltext_url": null,
  "id": "eqc16gj0be0ph",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.17272",
  "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.GA"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2608.17272",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/eqc16gj0be0ph.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2608.17272",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.17272"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "The VariableTNG project: how baryonic mechanisms shape galaxy properties",
  "title_text": "The VariableTNG project: how baryonic mechanisms shape galaxy properties",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/eqc16gj0be0ph",
  "venue": "arXiv",
  "versions": []
}