{
  "abstract": "We construct an exact rotating vacuum of the NS--NS sector, equivalently a Double Field Theory vacuum. The construction applies compact $\\mathbf{SO}(2)$ S-duality to a rotating Einstein--scalar seed. The solution has four independent parameters $\\{\\mathfrak{m},j,\\mathfrak{q},ζ\\}$. To our knowledge, this is the first explicit rotating solution of the pure NS--NS vacuum equations with all three NS--NS fields $\\{g,B,ϕ\\}$ determined analytically, independent dilaton and $H$-flux charges, and no Maxwell sector. The static limit is obtained by taking the rotation parameter $j\\to 0$. In this limit the geometry is not the spherical Burgess--Myers--Quevedo solution. Instead, it is an axial Zipoy--Voorhees branch carrying $H$-flux, so an oblate deformation remains after rotation is switched off. This geometric memory is absent in pure general relativity and in Einstein--Maxwell--dilaton--axion. The two static branches nevertheless share the same $\\ell=0$ parametrized post-Newtonian data $\\{MG,β_{\\mathrm{PPN}},γ_{\\mathrm{PPN}},h\\}$. They give two inequivalent NS--NS geometries at identical monopole charges, with the degeneracy lifted at $\\ell=2$. At the Kerr horizon locus the outer shell is generically singular in curvature. Above the threshold $|\\mathfrak{q}|>\\sqrt{\\mathfrak{m}^{2}-j^{2}}$, polar geodesics are repelled outward and the rotation axis becomes regular in curvature at the shell. On that axis the inverse metric $g^{μν}$ stays finite while the lower-index Riemannian metric components diverge, whereas off the axis the inverse metric itself diverges. This axis-local degeneracy may offer a setting for non-Riemannian geometry in Double Field Theory, where $g_{μν}$ is not fundamental and the $\\mathbf{O}(D,D)$ variables $\\{d,\\mathcal{H}_{AB}\\}$ remain well defined.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: JHEP09(2026)231",
  "arxiv": "2606.08889",
  "author_total": 3,
  "authors": [
    {
      "name": "Hun Jang"
    },
    {
      "name": "Minkyoo Kim"
    },
    {
      "name": "Jeong-Hyuck Park"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ddsx2kx899khv.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2606.08889",
  "fulltext_url": null,
  "id": "ddsx2kx899khv",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2606.08889",
  "language": null,
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "gr-qc"
    ],
    [
      "arxiv",
      "hep-th"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2606.08889",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-10",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ddsx2kx899khv.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:56Z",
      "native_id": "2606.08889",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2606.08889"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    },
    {
      "field": "physics",
      "origin": "arxiv:hep-th",
      "subfield": "high-energy"
    }
  ],
  "title": "Exact Four-Parameter Rotating NS--NS Vacuum in Double Field Theory",
  "title_text": "Exact Four-Parameter Rotating NS--NS Vacuum in Double Field Theory",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:56Z",
  "url": "https://research.draconitic.com/paper/ddsx2kx899khv",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1007/jhep09(2026)231",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}