@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-00991429v1> a dcat:Dataset ;
    dct:description """
              The Bogoliubov-Dirac-Fock (BDF) model is a no-photon, mean-field approxi- mation of quantum electrodynamics. It describes relativistic electrons in the Dirac sea. In this model, a state is fully characterized by its one-body density matrix, an infinite rank nonnegative operator. We prove the existence of the positronium, the bound state of an electron and a positron, represented by a critical point of the energy functional in the absence of external field. This state is interpreted as the ortho-positronium, where the two particles have parallel spins.
            """ ;
    dct:identifier "hal-00991429" ;
    dct:issued "2026-05-05T11:10:59.130365"^^xsd:dateTime ;
    dct:language "en" ;
    dct:modified "2026-05-05T11:10:59.130369"^^xsd:dateTime ;
    dct:publisher <https://rec.harvest-normandie.data4citizen.com/organization/cce9db95-46d9-4dc2-84b6-764215d0a002> ;
    dct:title "The positronium in a mean-field approximation of quantum electrodynamics." ;
    dcat:contactPoint [ a vcard:Organization ;
            vcard:fn "CCSD" ] ;
    dcat:distribution <https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-hal-00991429v1/resource/173871d4-4610-4227-8ef7-fc146b7ffadf> ;
    dcat:keyword "bdf-energy",
        "critical-point",
        "dirac-operator",
        "infoeu-reposemanticspreprint",
        "mathmath-mpmathematics-mathmathematical-physics-math-ph",
        "mean-field",
        "msc2010-47j20-49j40-49j45",
        "positronium",
        "preprints-working-papers-" ;
    dcat:landingPage <https://hal.science/hal-00991429> .

<https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-hal-00991429v1/resource/173871d4-4610-4227-8ef7-fc146b7ffadf> a dcat:Distribution ;
    dct:format "HTML" ;
    dct:issued "2026-05-05T11:10:59.135398"^^xsd:dateTime ;
    dct:modified "2026-05-05T11:10:59.118487"^^xsd:dateTime ;
    dct:title "The positronium in a mean-field approximation of quantum electrodynamics." ;
    dcat:accessURL <https://hal.science/hal-00991429> .

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

<https://hal.science/hal-00991429> a foaf:Document .