Spherically symmetric and static black bounces with multiple horizons, throats, and anti-throats in four dimensions

TL;DR

This paper introduces new classes of four-dimensional black bounce spacetimes with multiple horizons, throats, and anti-throats, extending previous models by incorporating scalar fields and nonlinear electrodynamics.

Contribution

It presents novel solutions with complex horizon and throat structures, based on modifications of Schwarzschild and Simpson-Visser metrics, and analyzes their physical properties.

Findings

Solutions exhibit multiple horizons, throats, and anti-throats.

Energy conditions vary, being satisfied or violated in different regions.

Spacetime regularity is confirmed via Kretschmann scalar analysis.

Abstract

Black bounce spacetimes usually arise from the Simpson-Visser regularization method. This type of metric presents a wormhole throat inside an event horizon. In this paper, we presented new classes of black bounce spacetime solutions, which have multiple horizons, throats, and anti-throats. These solutions are variants of black holes and wormholes, based on modifications of the Schwarzschild and Simpson-Visser metrics. The metric function allows for multiple horizons and throats, and the asymptotic behavior recovers the Schwarzschild solution. The article considers a scalar field coupled to nonlinear electrodynamics, generating solutions with a partially phantom scalar field and a magnetic monopole. The energy conditions can be satisfied or violated depending on the region of spacetime, analyzed through an anisotropic fluid. The regularity of the spacetime is ensured by the analysis of the Kretschmann scalar.