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arXiv · 2101.06410

Black holes of $(2+1)$-dimensional $f(R)$ gravity coupled to a scalar field

Thanasis Karakasis·Eleftherios Papantonopoulos·Zi-Yu Tang·Bin Wang
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Abstract

We consider $f(R)$ gravity theories in the presence of a scalar field minimally coupled to gravity with a self-interacting potential in $(2+1)$-dimensions. Without specifying the form of the $f(R)$ function, we first obtain an exact black hole solution dressed with scalar hair with the scalar charge to appear in the $f(R)$ function and we discuss its thermodynamics. This solution at large distances gives a hairy BTZ black hole, and it reduces to the BTZ black hole when the scalar field decouples. In a pure $f(R)$ gravity supported by the scalar field, we find an exact hairy black hole similar to the BTZ black hole with phantom hair and an analytic $f(R)$ form and discuss its thermodynamics.

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Thanasis Karakasis, Eleftherios Papantonopoulos, Zi-Yu Tang, Bin Wang. 2021-01-16. Black holes of $(2+1)$-dimensional $f(R)$ gravity coupled to a scalar field. https://doi.org/10.1103/physrevd.103.064063

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