{
  "abstract": "All recent advances \\cite{DRS}, \\cite{S-Rita1}, \\cite{S-Rita2}, \\cite{Millet}, \\cite{MaS}, \\cite{MaS2} on the boundedness and decay for wave equations on subextremal Kerr spacetimes $\\KK(a,m)$, with non-small angular rotation, rely in an essential way on Whiting's groundbreaking discovery of a powerful integro-differential transformation with the help of which he ruled out exponentially growing modes in \\cite{W} (see also \\cite{Yacov}, \\cite{AMPW} and \\cite{Rita} for further developments). We give a purely \\textit{physical space}, generalized version, of the transformation which takes general solutions of {spin-$\\sk$} wave equations in $\\KK=\\KK(a,m)$ to solutions of a secondary wave equation on a new metric manifold $\\KKt=\\KKt(a,m)$ with two stationary, asymptotically flat, ends. Moreover, for a certain subdomain $\\DDt\\subset\\DDt_-$, which can be identified as the exterior of a black hole region, the new metric $\\gt$ of $\\KKt(a, m)$ is Lorentzian and the time translation $\\T $ is timelike. Using the geometric properties of the two ends one can then deduce, by classical asymptotic Fourier analysis techniques, the desired bound for the flux of $ψ$ at the future event horizon. This estimate played a crucial role in our companion paper \\cite{He-K1}.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.06344",
  "author_total": 2,
  "authors": [
    {
      "name": "Lili He"
    },
    {
      "name": "Sergiu Klainerman"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dsetxy5ehvsdw.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.06344",
  "fulltext_url": null,
  "id": "dsetxy5ehvsdw",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.06344",
  "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",
      "math-ph"
    ],
    [
      "arxiv",
      "math.AP"
    ],
    [
      "arxiv",
      "math.MP"
    ],
    [
      "openalex",
      "3106|Black Holes and Theoretical Physics"
    ]
  ],
  "openalex": "W7211997660",
  "pdf_url": "https://arxiv.org/pdf/2609.06344",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-27",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/dsetxy5ehvsdw.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:12Z",
      "native_id": "2609.06344",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.06344"
    }
  ],
  "subjects": [
    {
      "field": "mathematics",
      "origin": "arxiv:math.AP",
      "subfield": "analysis-pdes"
    },
    {
      "field": "mathematics",
      "origin": "arxiv:math-ph",
      "subfield": "mathematical-physics"
    },
    {
      "field": "physics",
      "origin": "arxiv:gr-qc",
      "subfield": "gravitation"
    }
  ],
  "title": "Generalized Whiting transform and Flux Estimates for Wave Equations in Subextremal Kerr",
  "title_text": "Generalized Whiting transform and Flux Estimates for Wave Equations in Subextremal Kerr",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:17Z",
  "url": "https://research.draconitic.com/paper/dsetxy5ehvsdw",
  "venue": "arXiv",
  "versions": []
}