https://doi.org/10.1140/epjc/s10052-023-11570-3
Regular Article - Theoretical Physics
Gödel-type universes in energy–momentum-squared gravity
Instituto de Física, Universidade Federal de Mato Grosso, 78060-900, Cuiabá, Mato Grosso, Brazil
b
alesandroferreira@fisica.ufmt.br
Received:
10
March
2023
Accepted:
29
April
2023
Published online:
13
May
2023
In this paper, a modification of general relativity is considered. It consists of generalizing the Lagrangian of matter in a non-linear way, that is, replacing the curvature scalar R by a function , where
is the energy–momentum tensor. The main objective is to investigate the issue of causality in this gravitational model. To study the causality and/or its violation the Gödel-type solutions are used. For such development, different matter contents are chosen. A critical radius, beyond which causality is violated, is calculated. It is shown that both causal and non-causal solutions are allowed.
© The Author(s) 2023
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