@prefix dcat: <http://www.w3.org/ns/dcat#> .
@prefix dct: <http://purl.org/dc/terms/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix vcard: <http://www.w3.org/2006/vcard/ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-hal-00778411v3> a dcat:Dataset ;
    dct:description """
              It is a classical fact that the cotangent bundle $T^* M$ of a differentiable manifold $M$ enjoys a canonical symplectic form $\\Omega^*$. If $(M,j,g,\\omega)$ is a pseudo-Kähler or para-Kähler $2n$-dimensional manifold, we prove that the tangent bundle $T M$ also enjoys a natural pseudo-Kähler or para-Kähler structure $(J,G,\\Omega)$, where $\\Omega$ is the pull-back by $g$ of $\\Omega^*$ and $G$ is a pseudo-Riemannian metric with neutral signature $(2n,2n)$. We investigate the curvature properties of the pair $(J,G)$ and prove that: $G$ is scalar-flat, is not Einstein unless $g$ is flat, has nonpositive (resp.\\ nonnegative) Ricci curvature if and only if $g$ has nonpositive (resp.\\ nonnegative) Ricci curvature as well, and is locally conformally flat if and only if $n=1$ and $g$ has constant curvature, or $n>2$ and $g$ is flat. We also check that (i) the holomorphic sectional curvature of $(J,G)$ is not constant unless $g$ is flat, and (ii) in $n=1$ case, that $G$ is never anti-self-dual, unless conformally flat.
            """ ;
    dct:identifier "hal-00778411" ;
    dct:issued "2026-05-09T22:16:57.628646"^^xsd:dateTime ;
    dct:language "en" ;
    dct:modified "2026-05-09T22:16:57.628650"^^xsd:dateTime ;
    dct:publisher <https://rec.harvest-normandie.data4citizen.com/organization/cce9db95-46d9-4dc2-84b6-764215d0a002> ;
    dct:title "A canonical structure on the tangent bundle of a pseudo- or para-Kähler manifold" ;
    dcat:contactPoint [ a vcard:Organization ;
            vcard:fn "CCSD" ] ;
    dcat:distribution <https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-hal-00778411v3/resource/24a02639-0103-4d5b-bfb3-611fa7736694> ;
    dcat:keyword "32q15-53d05",
        "complex-structure",
        "infoeu-reposemanticsarticle",
        "journal-articles",
        "mathmath-dgmathematics-mathdifferential-geometry-mathdg",
        "para-complex-structure",
        "pseudo-riemannian-metric",
        "tangent-bundle" ;
    dcat:landingPage <ISSN:%200026-9255> .

<ISSN:%200026-9255> a foaf:Document .

<https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-hal-00778411v3/resource/24a02639-0103-4d5b-bfb3-611fa7736694> a dcat:Distribution ;
    dct:format "HTML" ;
    dct:issued "2026-05-09T22:16:57.635268"^^xsd:dateTime ;
    dct:modified "2026-05-09T22:16:57.617460"^^xsd:dateTime ;
    dct:title "A canonical structure on the tangent bundle of a pseudo- or para-Kähler manifold" ;
    dcat:accessURL <https://hal.science/hal-00778411> .

<https://rec.harvest-normandie.data4citizen.com/organization/cce9db95-46d9-4dc2-84b6-764215d0a002> a foaf:Agent ;
    foaf:name "test_moissonnage_selune" .