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arXiv · 2102.01600

On the causality properties in non-local gravity theories

J. R. Nascimento·A. Yu. Petrov·P. J. Porfírio
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Abstract

It is well known that non-local theories of gravity have been a flourish arena of studies for many reasons, for instance, the UV incompleteness of General Relativity (GR). In this paper we check the consistency of ST-homogeneous G\"{o}del-type metrics within the non-local gravity framework. The non-local models considered here are ghost-free but not necessarily renormalizable since we focus on the classical solutions of the field equations. Furthermore, the non-locality is displayed in the action through transcendental entire functions of the d'Alembert operator $\Box$ that are mathematically represented by a power series of the $\Box$-operator. We find two exactly solutions for the field equations correspondent to the degenerate ($\omega=0$) and hyperbolic ($m^{2}=4\omega^2$) classes of ST-homogeneous G\"{o}del-type metrics.

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J. R. Nascimento, A. Yu. Petrov, P. J. Porfírio. 2021-02-02. On the causality properties in non-local gravity theories. https://doi.org/10.1140/epjc%2Fs10052-021-09640-5

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