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arXiv · 1912.06471

Lagrangian formalism for Rastall theory of gravity and G\"{o}del-type universe

W. A. G. De Moraes·A. F. Santos
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Abstract

In the Rastall gravity a non-minimal coupling between geometry and matter fields is considered. Then the usual energy-momentum tensor conservation law is not valid. Here a Lagrangian formalism is proposed to the Rastall theory of gravity. The G\"{o}del-type universe is studied in this gravitational model. Then it is studied whether this theory permits causality violation. The field equations do not exclude solutions with a breakdown of causality for a perfect fluid as matter content. In this case, an expression for the critical radius (beyond which the causality is violated) is determined. In addition, for a combination between perfect fluid and scalar field as matter content the theory accommodates causal G\"{o}del-type solution.

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W. A. G. De Moraes, A. F. Santos. 2019-12-10. Lagrangian formalism for Rastall theory of gravity and G\"{o}del-type universe. https://arxiv.org/abs/1912.06471

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