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arXiv · 1808.02427

Imperfect fluid description of modified gravities

Valerio Faraoni·Jeremy Coté
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Abstract

The Brans-Dicke-like field of scalar-tensor gravity can be described as an imperfect fluid in an approach in which the field equations are regarded as effective Einstein equations. After completing this approach we recover, as a special case, the known effective fluid for a scalar coupled nonminimally to the Ricci curvature and we describe the imperfect fluid equivalent of f(R) gravity. A symmetry of electrovacuum Brans-Dicke gravity is translated into a symmetry of the corresponding effective fluid. The discussion is valid for any spacetime geometry.

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Valerio Faraoni, Jeremy Coté. 2018-10-09. Imperfect fluid description of modified gravities. https://doi.org/10.1103/physrevd.98.084019

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