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arXiv · 2603.22517

Reconstructed black hole solutions in the scalar-tensor theory with nonminimal coupling

K. K. Ernazarov
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Abstract

We consider the scalar-tensor theory witn non-minimal coupling in the Jordan frame. The action of the model contains a potential term $U(\varphi)$, a coupling function $f(\varphi)$. We explore a reconstruction procedure for a generic static spherically symmetric metric written in the Buchdahl parametrization: $ds^2 = \left(A(u)\right)^{-1}du^2 - A(u)dt^2 + C(u)d\Omega^2$, with given $A(u) > 0$ and $C(u) > 0$. The procedure gives the relations for $U(\varphi(u))$, $f(\varphi(u))$ and $d\varphi/du$, which lead to exact solutions to equations of motion with a given metric. A key role in this approach is played by the solutions to a first order linear differential equation for the function $f(\varphi(u))$. The formalism is illustrated by two examples when: a) the Reissner-Nordstr\"om-(Anti-)de Sitter metric and b) the Bocharova-Bronnikov-Melnikov-Bekenstein-(Anti)de-Sitter metric are chosen as a starting point.

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K. K. Ernazarov. 2026-03-23. Reconstructed black hole solutions in the scalar-tensor theory with nonminimal coupling. https://arxiv.org/abs/2603.22517

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