{
  "abstract": "One of the central expectations of quantum gravity is the resolution of the curvature singularities predicted by General Relativity, potentially giving rise to effective black-hole geometries that are regular inside the horizon. We show that, for a very broad class of regular black holes including several known solutions, the quasinormal-mode spectrum in the large-overtone limit differs discontinuously from that of a Schwarzschild black hole, even when the regularization parameter is arbitrarily small. The real part of the quasinormal frequencies vanishes asymptotically, rather than approaching a nonzero constant, as generically occurs in General Relativity and other theories predicting black holes with curvature singularities. The asymptotic black-hole spectrum thus retains a distinctive imprint of singularity resolution. We establish these results analytically through a systematic formulation of the monodromy method and confirm them numerically. We interpret this phenomenon as a manifestation of black-hole spectral instability, whereby arbitrarily small deviations from vacuum General Relativity produce nonperturbative changes in the large-overtone spectrum.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.37028",
  "author_total": 3,
  "authors": [
    {
      "name": "Matteo Della Rocca"
    },
    {
      "name": "Paolo Pani"
    },
    {
      "name": "Andrea P. Sanna"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2h9m50ewsjja0.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.37028",
  "fulltext_url": null,
  "id": "2h9m50ewsjja0",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.37028",
  "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",
      "gr-qc"
    ],
    [
      "arxiv",
      "hep-th"
    ],
    [
      "openalex",
      "3106|Black Holes and Theoretical Physics"
    ]
  ],
  "openalex": "W7224120741",
  "pdf_url": "https://arxiv.org/pdf/2610.37028",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-27",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2h9m50ewsjja0.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:50Z",
      "native_id": "2610.37028",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.37028"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-th",
      "subfield": "high-energy"
    }
  ],
  "title": "Can One Hear the Absence of a Singularity?",
  "title_text": "Can One Hear the Absence of a Singularity?",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:50Z",
  "url": "https://research.draconitic.com/paper/2h9m50ewsjja0",
  "venue": "arXiv",
  "versions": []
}