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arXiv · 2107.00393

G\"{o}del-type solutions in hybrid metric-Palatini gravity

J. S. Gonçalves·A. F. Santos
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Abstract

In this paper, the hybrid metric-Palatini gravity is an approach to modified gravity in which is added to the usual Einstein-Hilbert action a supplementary term containing a Palatini-type correction of the form $f({\cal R},T)$. Here, ${\cal R}$ is the Palatini curvature scalar, which is constructed from an independent connection and $T$ is the trace of the energy-momentum tensor. This theory describes a non-minimal coupling between matter and geometry. The modified Einstein field equations in this hybrid metric-Palatini approach are obtained. Then, it is investigated whether this modified theory of gravity and its field equations allow G\"{o}del-type solutions, which essentially lead to violation of causality. Considering physically well-motivated matter sources, causal and non-causal solutions are explored.

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J. S. Gonçalves, A. F. Santos. 2021-07-01. G\"{o}del-type solutions in hybrid metric-Palatini gravity. https://doi.org/10.1209/0295-5075%2Fac0ffd

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