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arXiv · 2411.16050

Regular black holes inspired by quasi-topological gravity

Valeri P. Frolov·Alex Koek·Jose Pinedo Soto·Andrei Zelnikov
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Abstract

Recently it was demonstrated that by adding to the Einstein-Hilbert action a series in powers of the curvature invariants with specially chosen coefficients one can obtain a theory of gravity which has spherically symmetric solutions describing regular black holes. Its reduced action depends on a function of one of the basic curvature invariants of the corresponding metric. In this paper we study a generalization of this model to the case when this function depends on all the basic curvature invariants. We show that the metrics which are solutions of such a model possess a universal scaling property. We demonstrate that there exists a special class of such models for which the ``master" equation for a basic curvature invariant is a linear second order ordinary differential equation. We specify a domain in the space of parameters of the model for which the corresponding solutions describe regular static spherically symmetric black holes and study their properties.

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Valeri P. Frolov, Alex Koek, Jose Pinedo Soto, Andrei Zelnikov. 2024-11-25. Regular black holes inspired by quasi-topological gravity. https://doi.org/10.1103/physrevd.111.044034

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