{
  "abstract": "Recently, it has been proposed that the classical effective action of bosonic string theory should contain only couplings with an even number of tachyon fields. We employ the T-duality procedure to derive such couplings at order α′ (four-derivative order) for the tachyon and massless fields. We first observe that, through higher-derivative field redefinitions of the tachyon potential term, one can choose a scheme in which — apart from the tachyon potential itself — all remaining couplings involve only covariant derivatives of the tachyon and the massless fields. We then construct a minimal basis of such couplings at four-derivative order, consisting of 14 independent terms. Imposing T-duality reduces this set to 6 nonzero couplings, expressed in terms of two unfixed parameters. One of these parameters is determined by matching to the known effective action in the zero-tachyon limit, while the other is fixed by comparison with the sphere-level S-matrix element of four tachyon vertex operators. This latter comparison also establishes that the coefficient of the T 4 term in the tachyon potential is positive. Remarkably, the tachyon mass term and this quartic term are consistent with a potential of the form (2/α′)(– 1 + cos T), which implies that the closed string tachyon condenses to the minimum of the potential at T = π, thereby generating an Anti-de Sitter spacetime with cosmological constant Λ = −4/α′.",
  "abstract_shown": true,
  "affiliations": [
    "Ferdowsi University of Mashhad"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Mohammad R. Garousi",
      "orcid": "0000-0002-8992-2372"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c90cdsa5tpznq.bib",
  "cited_by": 0,
  "doi": "10.1007/jhep10(2026)258",
  "fulltext_url": null,
  "id": "c90cdsa5tpznq",
  "issns": [
    "1029-8479"
  ],
  "landing_url": "https://link.springer.com/article/10.1007/JHEP10(2026)258",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0",
  "metadata_licence": null,
  "native_subjects": [
    [
      "feed-journal",
      "physics/high-energy"
    ],
    [
      "openalex",
      "3106|Black Holes and Theoretical Physics"
    ]
  ],
  "openalex": "W7212044290",
  "pdf_url": "https://link.springer.com/content/pdf/10.1007/JHEP10(2026)258.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-26",
  "publisher": "Springer Science and Business Media LLC",
  "ris": "https://research.draconitic.com/paper/c90cdsa5tpznq.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:17Z",
      "native_id": "10.1007/jhep10(2026)258",
      "source": "feed-springer",
      "url": "https://link.springer.com/article/10.1007/JHEP10(2026)258"
    },
    {
      "first_seen": "2026-10-30T12:18:01Z",
      "native_id": "10.1007/jhep10(2026)258",
      "source": "crossref",
      "url": "https://link.springer.com/article/10.1007/JHEP10(2026)258"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3106|Black Holes and Theoretical Physics",
      "subfield": "high-energy"
    }
  ],
  "title": "Tachyon-massless couplings at order α′ in bosonic string theory",
  "title_text": "Tachyon-massless couplings at order α′ in bosonic string theory",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:01Z",
  "url": "https://research.draconitic.com/paper/c90cdsa5tpznq",
  "venue": "Journal of High Energy Physics",
  "versions": []
}