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Nonstaticity theorem for type II, III, and IV matter fields in $f(R_{mu urhosigma},g^{mu u})$ gravity

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 نشر من قبل Hideki Maeda
 تاريخ النشر 2020
  مجال البحث فيزياء
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 تأليف Hideki Maeda




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In all $n(ge 3)$-dimensional gravitation theories whose Lagrangians are functions of the Riemann tensor and metric, we prove that static solutions are absent unless the total energy-momentum tensor for matter fields is of type I in the Hawking-Ellis classification. In other words, there is no hypersurface-orthogonal timelike Killing vector in a spacetime region with an energy-momentum tensor of type II, III, or IV. This asserts that ultra-dense regions with a semiclassical type-IV matter field cannot be static even with higher-curvature correction terms.



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