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arXiv · 2001.11335

Nonstaticity with type II, III, or IV matter field in $f(R_{\mu\nu\rho\sigma},g^{\mu\nu})$ gravity

Hideki Maeda
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Abstract

In all $n(\ge 3)$-dimensional gravitation theories whose Lagrangians are functions of the Riemann tensor and metric, we show 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, if back-reaction is taken into account to give a self-consistent solution, ultra-dense regions with a semiclassical type-IV matter field cannot be static even with higher-curvature correction terms. As a consequence, a static Planck-mass relic is possible as a final state of an evaporating black hole only if the semiclassical total energy-momentum tensor is of type I.

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Hideki Maeda. 2020-01-29. Nonstaticity with type II, III, or IV matter field in $f(R_{\mu\nu\rho\sigma},g^{\mu\nu})$ gravity. https://doi.org/10.1007/s10714-021-02862-8

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