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arXiv · 2302.09935

G\"{o}del-type solutions within the $f(R,Q,P)$ gravity

J. R. Nascimento·A. Yu. Petrov·P. J. Porfirio·Ramires N. da Silva
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Abstract

In this work, we scrutinize the consistency of spacetime homogeneous G\"{o}del-type metrics within $f(R,Q,P)$ theories of gravity for well-motivated matter sources. As it is well known, such geometries allow for causality violation. We provide general conditions to engender completely causal solutions in a manner completely different from general relativity. We take some specific models, for instance, $f(R,Q,P)=R -\dfrac{\mu^{4n+2}}{\left(a R^2+b Q+c P\right)^n}$, to illustrate the general results. Notably, we also find an unusual completely causal vacuum solution in the presence of a non-trivial cosmological constant which corresponds to the case $m^2=4\omega^2$.

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J. R. Nascimento, A. Yu. Petrov, P. J. Porfirio, Ramires N. da Silva. 2023-02-20. G\"{o}del-type solutions within the $f(R,Q,P)$ gravity. https://doi.org/10.1140/epjc/s10052-023-11521-y

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