{
  "abstract": "Boruch, Emparan, Iliesiu, and Murthy recently discussed index saddles for 5d black strings, showing that the black string saddle admits a decoupling limit to a complex, finite-temperature BTZ \\times S^2 saddle that computes the index of the dual CFT. In this paper, we pursue an analogous construction for the D1-D5-P black string. We construct a four-charge index saddle in the four-dimensional STU model as the BPS limit of the non-extremal four-charge black hole, and show that it exhibits the new form of attraction. We then uplift it successively to five and six dimensions, via the 4D-5D connection and a chain of string dualities, to obtain the gravitational index saddle for the D1-D5-P black string. We take a systematic decoupling limit of this index saddle and obtain the BTZ \\times S^3 saddle that computes the index of the D1-D5 CFT.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2606.27093",
  "author_total": 3,
  "authors": [
    {
      "name": "Kanhu Kishore Nanda"
    },
    {
      "name": "P Shanmugapriya"
    },
    {
      "name": "Amitabh Virmani"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/31hr6s57kn5t9.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.27093",
  "fulltext_url": null,
  "id": "31hr6s57kn5t9",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.27093",
  "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"
    ],
    [
      "arxiv",
      "hep-th"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2606.27093",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/31hr6s57kn5t9.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:31Z",
      "native_id": "2606.27093",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.27093"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-th",
      "subfield": "high-energy"
    }
  ],
  "title": "Index saddle for the D1-D5-P black string and its decoupling limit",
  "title_text": "Index saddle for the D1-D5-P black string and its decoupling limit",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:31Z",
  "url": "https://research.draconitic.com/paper/31hr6s57kn5t9",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1007/jhep10(2026)123",
      "pid": "74fexpq6txq9y",
      "relation": "published-as",
      "title": "Index saddle for the D1-D5-P black string and its decoupling limit",
      "venue": "Journal of High Energy Physics"
    }
  ]
}