{
  "abstract": "We explore rigidity results for compact Riemannian and spacelike hypersurfaces in Einstein manifolds. We show that for a compact Riemannian (or spacelike) hypersurface (M,g) in an Einstein Riemannian (or Lorentzian) manifold (M¯,g¯) which admits a closed conformal vector field ξ¯ (assumed to be timelike in the Lorentzian case), the hypersurface (M,g) is an extrinsic sphere in (M¯,g¯) if and only if it is not totally geodesic and the integral of the Ricci curvature of the hypersurface, taken in the direction of the tangential component ξ⊤ of the restriction ξ of ξ¯ to M, satisfies a certain lower bound. As an application of this result, we investigate compact spacelike hypersurfaces in generalized Robertson–Walker (GRW) spacetimes. Additionally, other related results are also provided.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Mathematics, College of Sciences, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Mohammed Guediri",
      "orcid": "0000-0002-0775-2323"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1y6fy17qb3wtv.bib",
  "cited_by": 0,
  "doi": "10.3390/math14213881",
  "fulltext_url": null,
  "id": "1y6fy17qb3wtv",
  "issns": [
    "2227-7390"
  ],
  "landing_url": "https://www.mdpi.com/2227-7390/14/21/3881",
  "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": [
    [
      "openalex",
      "3103|Advanced Differential Geometry Research"
    ]
  ],
  "openalex": "W7223670552",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-24",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/1y6fy17qb3wtv.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:29Z",
      "native_id": "10.3390/math14213881",
      "source": "crossref",
      "url": "https://www.mdpi.com/2227-7390/14/21/3881"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "openalex:3103|Advanced Differential Geometry Research",
      "subfield": "general"
    }
  ],
  "title": "Characterization of Compact Riemannian and Spacelike Hypersurfaces in Einstein Manifolds",
  "title_text": "Characterization of Compact Riemannian and Spacelike Hypersurfaces in Einstein Manifolds",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:29Z",
  "url": "https://research.draconitic.com/paper/1y6fy17qb3wtv",
  "venue": "Mathematics",
  "versions": []
}