{
  "abstract": "We apply the functional renormalization group to the worldsheet theory of the bosonic string. Imposing the Weyl anomaly cancellation as a condition on the local renormalization group flow, we derive flow equations for the background couplings and the corresponding effective spacetime equations of motion, first in a two-derivative truncation, on a general curved background. We then consider a truncation to all orders in $α'$, which captures only a subset of the possible tensor structures but is analytically tractable, in analogy with $f(R)$-like approximations. Within this truncation, we obtain Tseytlin's spacetime effective action, and we use it to study solutions to all orders in $α'$, including black holes. Our results show that the functional renormalization group can be implemented on the string worldsheet and provide a framework to access the strong-curvature regime. As a longer-term goal, this may allow one to test the scenario of effective asymptotic safety in string theory, in which an approximately scale-invariant regime lies between the low-energy effective field theory and a stringy completion.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.03781",
  "author_total": 4,
  "authors": [
    {
      "name": "Ivano Basile"
    },
    {
      "name": "Francesco Ferrarin"
    },
    {
      "name": "Alessia Platania"
    },
    {
      "name": "Matteo Zatti"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4f0684f0nqkvd.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.03781",
  "fulltext_url": null,
  "id": "4f0684f0nqkvd",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.03781",
  "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",
      "hep-th"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.03781",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/4f0684f0nqkvd.ris",
  "sources": [
    {
      "first_seen": "2026-11-04T15:21:25Z",
      "native_id": "2611.03781",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.03781"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:hep-th",
      "subfield": "high-energy"
    }
  ],
  "title": "Worldsheet functional RG and the $α'$-tower",
  "title_text": "Worldsheet functional RG and the α'-tower",
  "type": "preprint",
  "updated_at": "2026-11-06T18:21:01Z",
  "url": "https://research.draconitic.com/paper/4f0684f0nqkvd",
  "venue": "arXiv",
  "versions": []
}