{
  "abstract": "We construct static, asymptotically flat regular black holes in Einstein-frame scalar--tensor gravity, sourced by a canonical scalar coupled to magnetic nonlinear electrodynamics. Prescribing the density and scalar profiles, we reconstruct the metric, the scalar--photon coupling and the potential. Regularity requires the mass function to vanish at the centre, which fixes the ADM mass, and the central $r^2$ growth of the density to be compensated by the gradient energy of the scalar. The solutions have an anti-de Sitter core supported by a negative potential and a nearly Reissner--Nordström exterior; absence of ghosts restricts the magnetic charge to an interval that shrinks to zero at a finite core depth. Axial perturbations reduce to a symmetric two-channel master system whose positive-definite potential guarantees mode stability; spectral and time-domain quasinormal frequencies agree. Radial perturbations, by contrast, are unstable: the reconstructed potential behaves as $V\\propto-φ^5$ near the asymptotic vacuum, the scalar becomes tachyonic outside the horizon, and every ghost-free black hole has a growing monopole mode with $ΓM\\approx0.14$--$0.28$. An angular Laplacian instability develops near the centre; for black holes it may lie entirely within the inner horizon, while horizonless solutions leave it uncovered and are therefore excluded.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.28670",
  "author_total": 2,
  "authors": [
    {
      "name": "Rustam Ibadov"
    },
    {
      "name": "Najibullokhon Shukurullokhon"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/3mkqx6bcvxyg9.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.28670",
  "fulltext_url": null,
  "id": "3mkqx6bcvxyg9",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.28670",
  "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",
      "gr-qc"
    ],
    [
      "openalex",
      "3106|Black Holes and Theoretical Physics"
    ]
  ],
  "openalex": "W7223248539",
  "pdf_url": "https://arxiv.org/pdf/2610.28670",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-28",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/3mkqx6bcvxyg9.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:36:22Z",
      "native_id": "2610.28670",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.28670"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    }
  ],
  "title": "Regular magnetic black holes with anti-de Sitter cores in scalar-tensor gravity: axial stability and radial instability",
  "title_text": "Regular magnetic black holes with anti-de Sitter cores in scalar-tensor gravity: axial stability and radial instability",
  "type": "preprint",
  "updated_at": "2026-11-01T12:20:44Z",
  "url": "https://research.draconitic.com/paper/3mkqx6bcvxyg9",
  "venue": "arXiv",
  "versions": []
}